CN114746974B - Electronic circuit breaker and circuit breaker system - Google Patents

Abstract

The electronic circuit breaker (1) comprises a load current characteristic calculation unit (17) and an output unit (20). The load current characteristic calculation unit (17) calculates the current characteristic of the load in the short-time region, i.e., the short-time load current characteristic, based on the peak value calculated by the peak value calculation unit (12), and calculates the current characteristic of the load in the long-time region, i.e., the long-time load current characteristic, based on the effective value calculated by the effective value calculation unit (13). The output unit (20) outputs information on the load current characteristic including the short-time load current characteristic and the long-time load current characteristic calculated by the load current characteristic calculation unit (17).

Description

Electronic circuit breaker and circuit breaker system

Technical Field

The present invention relates to an electronic circuit breaker and a circuit breaker system.

Background

Conventionally, in an electronic circuit breaker having a microcomputer or the like, overcurrent trip operation characteristics can be changed. Therefore, when the load device is added or the operation mode of the load device is changed after the electronic circuit breaker is set, the electronic circuit breaker can be continuously used without replacing the electronic circuit breaker after the setting is completed by changing the overcurrent trip operation characteristic.

An operator who sets the overcurrent trip operation characteristic roughly calculates a load current, which is a current flowing through a load, based on a product specification of a full-load device constituting the load connected to the electronic circuit breaker. The operator sets the overcurrent trip operation characteristic with a margin slightly larger than the load current.

However, in the above-described operation, a time for approximately calculating the load current according to the product specification of the load device is required, and therefore, a technique for facilitating the setting of the overcurrent trip operation characteristic has been developed. For example, patent document 1 discloses an electronic circuit breaker in which a maximum energization continuation time with respect to each load current value is measured, and a characteristic indicating a relationship between the load current value and the maximum energization continuation time is calculated as a maximum load limit characteristic based on the measured result. The electronic circuit breaker displays characteristic information including maximum load time limit characteristics and overcurrent trip operation characteristics on a display unit, and can change the overcurrent trip operation characteristics. Thus, in the electronic circuit breaker described in patent document 1, the overcurrent trip operation characteristic can be easily set.

Patent document 1 Japanese patent laid-open publication No. 2010-93946

Disclosure of Invention

However, in the electronic circuit breaker described in patent document 1, an overcurrent is detected using a current integration value obtained by integrating a current product obtained by multiplying a load current effective value by a sampling period. Therefore, in the electronic circuit breaker described in patent document 1, for example, when the load is a generator, and when the overcurrent at a short-term time is detected and the circuit is broken by the flow of the starting current of the generator, the maximum load time limit characteristic may not exceed a value defined by the short-term operation characteristic among the overcurrent trip operation characteristics, and the overcurrent trip operation characteristic may not be performed appropriately.

The present invention has been made in view of the above circumstances, and an object thereof is to obtain an electronic circuit breaker in which a user can properly perform overcurrent trip operation characteristics.

In order to solve the above problems and achieve the object, an electronic circuit breaker of the present invention includes an opening/closing contact, a trip device, a current detecting unit, a peak value calculating unit, an effective value calculating unit, a short-time trip processing unit, a long-time trip processing unit, a load current characteristic calculating unit, and an output unit. The opening and closing contact opens and closes a circuit between the power source and the load. The trip device sets the opening and closing contact from the closed state to the open state. The current detection unit detects a current flowing through the circuit. The peak value calculation unit calculates a peak value of the current detected by the current detection unit. The effective value calculation unit calculates an effective value of the current detected by the current detection unit. The short-time trip processing unit sets the trip device to an open state from a closed state when it is determined that an overcurrent flows in the circuit in a region determined to be at a short time based on the peak value calculated by the peak value calculating unit. The long-time trip processing unit sets the trip device to an open state from a closed state when it is determined that an overcurrent flows in the circuit in a time limit longer than the short-time limit, that is, in a long-time limit region based on the effective value calculated by the effective value calculating unit. The load current characteristic calculation unit calculates a short-time-period load current characteristic, which is a current characteristic of the load in the short-time-period region, based on the peak value calculated by the peak value calculation unit, and calculates a long-time-period load current characteristic, which is a current characteristic of the load in the long-time-period region, based on the effective value calculated by the effective value calculation unit. The output unit outputs information of the load current characteristics including the short-time load current characteristics and the long-time load current characteristics calculated by the load current characteristic calculation unit.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, the user can perform the overcurrent trip characteristic appropriately.

Drawings

Fig. 1 is a diagram showing a configuration example of a circuit breaker system according to embodiment 1 of the present invention.

Fig. 2 is a diagram showing overcurrent trip operation characteristics and pre-alarm operation characteristics according to embodiment 1.

Fig. 3 is a diagram showing an example of the configuration of the information processing apparatus according to embodiment 1.

Fig. 4 is a diagram showing an example of characteristic information displayed by the information processing apparatus according to embodiment 1.

Fig. 5 is a diagram showing another example of characteristic information displayed by the information processing apparatus according to embodiment 1.

Fig. 6 is a flowchart showing an example of processing performed by the processing unit of the electronic circuit breaker according to embodiment 1.

Fig. 7 is a diagram showing an example of overcurrent trip operation characteristics of the electronic circuit breaker according to embodiment 1.

Fig. 8 is a flowchart showing an example of the short-time counter processing performed by the processing unit of the electronic circuit breaker according to embodiment 1.

Fig. 9 is a flowchart showing an example of load current characteristic calculation processing performed by the processing unit of the electronic circuit breaker according to embodiment 1.

Fig. 10 is a flowchart showing an example of TxP update processing performed by the processing unit of the electronic circuit breaker according to embodiment 1.

Fig. 11 is a diagram showing an example of load current in the case where the load according to embodiment 1 is a generator.

Fig. 12 is a diagram for explaining TxP updating processing in the 1 st cycle shown in fig. 11.

Fig. 13 is a diagram for explaining TxP updating processing in the 2 nd cycle shown in fig. 11.

Fig. 14 is a diagram for explaining TxP updating processing in the 3 rd cycle shown in fig. 11.

Fig. 15 is a diagram for explaining TxP updating processing in the 4 th cycle shown in fig. 11.

Fig. 16 is a diagram for explaining TxP updating processing in the 5 th cycle shown in fig. 11.

Fig. 17 is a diagram for explaining TxP updating processing in the 6 th cycle shown in fig. 11.

Fig. 18 is a diagram for explaining TxP updating processing in the 7 th cycle shown in fig. 11.

Fig. 19 is a diagram for explaining TxP updating processing in the 99 th cycle shown in fig. 11.

Fig. 20 is a diagram for explaining TxS update processing in the 1 st and 2 nd periods shown in fig. 11.

Fig. 21 is a diagram for explaining TxS update processing in the 3 rd and 4 th cycles shown in fig. 11.

Fig. 22 is a diagram for explaining TxS update processing in the 5 th and 6 th cycles shown in fig. 11.

Fig. 23 is a diagram for explaining TxS update processing in the 7 th cycle and 99 th cycle shown in fig. 11.

Fig. 24 is a diagram showing an example of a hardware configuration of a processing unit of the electronic circuit breaker according to embodiment 1.

Detailed Description

The electronic circuit breaker and the circuit breaker system according to the embodiment of the present invention will be described in detail below with reference to the drawings. The present invention is not limited to the present embodiment.

Embodiment 1.

Fig. 1 is a diagram showing a configuration example of a circuit breaker system according to embodiment 1 of the present invention. As shown in fig. 1, a circuit breaker system 100 according to embodiment 1 includes an electronic circuit breaker 1 and an information processing apparatus 50. The information processing device 50 is a mobile device such as a smart phone, a tablet, or a portable computer. The electronic circuit breaker 1 and the information processing apparatus 50 are communicably connected to each other by short-range wireless communication such as Bluetooth (registered trademark).

The electronic circuit breaker 1 connects and breaks a 3-phase 3-wire circuit 6 that connects a power supply 2 and a load 3. The circuit 6 connecting the power supply 2 and the load 3 is not limited to a 3-phase 3-wire circuit, and may be, for example, a single-phase 2-wire circuit, a single-phase 3-wire circuit, or a 3-phase 4-wire circuit. In the example shown in fig. 1, the load 3 includes the electrical device 3 ₁ and the electrical equipment 3 ₂, but the load 3 is not limited to the example shown in fig. 1.

The electronic circuit breaker 1 includes an opening/closing contact 4 for opening/closing a circuit 6, a trip device 5 for setting the opening/closing contact 4 from a closed state to an open state, and a current detection unit 7 for detecting a load current, which is a current flowing through the circuit 6 to the load 3. The opening/closing contact 4 has opening/closing contacts 4 ₁～4₃ for opening/closing the corresponding circuit among the 3 circuits 6 ₁～6₃ constituting the circuit 6.

Each of the opening/closing contacts 4 ₁～4₃ has a fixed contact not shown and a movable contact not shown. The movable contact contacts the fixed contacts at the respective opening/closing contacts 4 ₁～4₃ to be in a closed state, and the power supply 2 provided in the electronic circuit breaker 1 is electrically connected to the load 3. Thus, a current flows through each circuit 6 ₁～6₃, and the electronic circuit breaker 1 is turned on.

Further, at each of the opening/closing contacts 4 ₁～4₃, the movable contact is separated from the fixed contact, and the opening/closing contact 4 is brought from the closed state to the open state, whereby the power supply 2 and the load 3 are electrically disconnected. Thus, the current of each circuit 6 ₁～6₃ is broken, and the electronic circuit breaker 1 is turned off.

The current detection unit 7 includes a plurality of inverters 8 ₁、8₂、8₃ that output analog current signals proportional to instantaneous values of load currents flowing through corresponding circuits among the circuits 6 and ₁、6₂、6₃, respectively, and a voltage conversion unit 9 that converts the plurality of analog current signals output from the inverters 8 and ₁、8₂、8₃ into a plurality of analog voltage signals.

The electronic circuit breaker 1 further includes a processing unit 10, a trip circuit 30, an input unit 31, and a notification unit 32. The processing unit 10 has information on overcurrent trip operation characteristics, which are detection characteristics of an overcurrent, and determines whether or not the load current detected by the current detection unit 7 is an overcurrent based on the overcurrent trip operation characteristics. When the processing unit 10 determines that the load current is an overcurrent, it outputs a trip signal S to the trip circuit 30.

For example, when the trip signal S is output from the processing unit 10, the trip circuit 30 drives the trip device 5 to cause the trip device 5 to perform a trip operation. The trip operation is an operation of setting the opening/closing contact 4 from the closed state to the open state. The input unit 31 includes a plurality of dials for setting information on the overcurrent trip operation characteristic and the advance warning operation characteristic, a measurement start button for causing the processing unit 10 to calculate a load current time limit characteristic described later, and the like. The notification unit 32 includes, for example, any 1 of a speaker, a lamp, and a display unit, and gives a warning in advance by sound, light, or an image based on a request from the processing unit 10.

The processing unit 10 has information on the pre-alarm operation characteristic, and determines whether or not the load current detected by the current detection unit 7 is in a state in which the pre-alarm is to be made, based on the pre-alarm operation characteristic. When it is determined that the load current is in a state where the alarm should be made in advance, the processing unit 10 outputs the alarm in advance.

Here, the overcurrent trip operation characteristic and the previous alarm operation characteristic will be described. Fig. 2 is a diagram showing overcurrent trip operation characteristics and pre-alarm operation characteristics according to embodiment 1. In fig. 2, the horizontal axis represents load current, and the vertical axis represents operation time.

The overcurrent trip operation characteristic is a characteristic indicating a relationship between an overcurrent determination threshold and trip operation time, which is used for determining whether or not an overcurrent flows. The overcurrent trip operation characteristics of the electronic circuit breaker 1 include an instantaneous trip characteristic, a short-time trip characteristic, and a long-time trip characteristic. The instantaneous trip characteristic defines an overcurrent determination threshold for a trip operation, that is, an instantaneous trip operation, in the instantaneous trip region. The short-time trip characteristic defines an overcurrent determination threshold for a trip operation, that is, a short-time trip operation, in the short-time trip region. The long-time trip characteristic defines an overcurrent determination threshold for a trip operation, that is, a long-time trip operation, in the long-time trip region. In the following, the short-time trip area may be referred to as a short-time area, and the long-time trip area may be referred to as a long-time area.

The pre-alarm operation characteristic is a characteristic indicating a relationship between a pre-alarm threshold value smaller than the overcurrent determination threshold value and a pre-alarm operation time, and when a current to be alerted flows through the circuit 6, an alarm is output from the electronic circuit breaker 1. This alarm is performed before an overcurrent flows in the circuit 6, and is called a pre-alarm.

Fig. 2 shows a maximum load current time limit characteristic in addition to the overcurrent trip operation characteristic and the previous alarm operation characteristic. The maximum load current time limit characteristic is a load current time limit characteristic obtained by measuring a load current value while the load current is at a maximum, and shows a relationship between each load current value and the maximum energization time. The load current time limit characteristic is a characteristic indicating a relationship between each load current value and the energization time. The energization time is a time compared with an operation time in the overcurrent trip operation characteristic, and when the energization time exceeds an operation time defined by the overcurrent trip operation characteristic, the electronic circuit breaker 1 performs a trip operation.

Returning to fig. 1, the processing unit 10 of the electronic circuit breaker 1 will be described. The processing unit 10 includes an AD (Analog-to-Digital) conversion unit 11, a peak value calculation unit 12, an effective value calculation unit 13, an instantaneous trip processing unit 14, a short-time trip processing unit 15, a long-time trip processing unit 16, a load current characteristic calculation unit 17, a pre-alarm processing unit 18, a recommended value calculation unit 19, an output unit 20, a communication unit 21, a setting unit 22, and a storage unit 23.

The AD converter 11 converts each of the plurality of analog voltage signals output from the current detector 7 into a digital signal for each period T1 set in advance. The digital signal contains a digital value representing the instantaneous value of the load current. The period T1 is, for example, 1[ ms ]. The AD converter 11 outputs the converted digital signals to the peak value calculator 12, the effective value calculator 13, and the instantaneous trip processor 14.

The peak value calculation unit 12 detects a load current peak value Ipeak, which is a peak value of the load current flowing through the circuit 6, based on the plurality of digital signals output from the AD conversion unit 11 for each period T2 set in advance. The period T2 is, for example, 20[ ms ].

The peak value calculation unit 12 calculates, for example, a maximum value of the instantaneous value of the load current in a preset period T3 as a peak value, that is, a load current peak value Ipeak, based on the plurality of digital signals output from the AD conversion unit 11. The period T3 is, for example, 20 msec in the case where the frequency of the ac voltage output from the power supply 2 is 50 hz.

The effective value calculation unit 13 calculates the effective value Irms of the load current, which is the effective value of the load current flowing through the circuit 6, based on the plurality of digital signals output from the AD conversion unit 11 for each period T2. For example, the effective value calculation unit 13 obtains a moving average of values obtained by squaring instantaneous values of the load current included in the digital signal outputted from the AD conversion unit 11, and calculates square roots of the results of the moving average, thereby obtaining the load current effective value Irms.

The instantaneous trip processing unit 14 determines whether or not the instantaneous value of the load current flowing through the circuit 6 exceeds an overcurrent determination threshold defined by the instantaneous trip operation characteristic, based on the plurality of digital signals output from the AD conversion unit 11, for each period T1. When the instantaneous trip processing unit 14 determines that the instantaneous value of the load current flowing through the circuit 6 exceeds the overcurrent determination threshold, the output unit 20 outputs the trip signal S to the trip circuit 30.

The short-time trip processing unit 15 determines whether or not an overcurrent flows in a short-time region of the circuit 6 based on the load current peak value Ipeak. Specifically, the short-time trip processing unit 15 outputs the trip signal S from the output unit 20 to the trip circuit 30 when the load current peak value Ipeak exceeds the overcurrent determination threshold defined by the short-time trip characteristic for each period T2.

The long-time trip processing unit 16 determines whether or not an overcurrent flows in the region where the circuit 6 is in the long-time based on the load current effective value Irms. Specifically, the long-time trip processing unit 16 outputs the trip signal S from the output unit 20 to the trip circuit 30 when the load current effective value Irms exceeds the overcurrent determination threshold defined by the long-time trip characteristic for each period T2. The long-time trip processing unit 16 can determine whether or not an overcurrent flows in the region where the circuit 6 is in the long-time period, based on the load current effective value Irms and the load current peak value Ipeak.

The load current characteristic calculation unit 17 calculates a load current time limit characteristic indicating a relationship between the load current and the energization time. The load current characteristic calculation unit 17 can calculate the maximum load current time limit characteristic indicating the relationship between the load current and the maximum conduction time by measuring the load current value while the load current is at the maximum.

Based on the load current peak value Ipeak, a load current time limit characteristic in a short-time-limit region, that is, a short-time-limit load current characteristic is calculated. The load current characteristic calculation unit 17 calculates a load current time limit characteristic, that is, a long-term load current characteristic in a long-term region, based on the load current effective value Irms. The short-time-limit load current characteristic is a characteristic representing a relationship between the load current and the energization time in the region at the short time limit, and the long-time-limit load current characteristic is a characteristic representing a relationship between the load current and the energization time in the region at the long time limit.

As described above, the load current characteristic calculation unit 17 calculates the short-time load current characteristic based on the load current peak value Ipeak used for the determination of the trip in the short-time trip processing unit 15, and calculates the long-time load current characteristic using the load current effective value Irms used for the determination of the trip in the long-time trip processing unit 16. Accordingly, the electronic circuit breaker 1 can present the load current time limit characteristic that matches the overcurrent trip operation characteristic to the user, and thus the user can appropriately perform the overcurrent trip operation characteristic.

When the user operates the measurement start button of the input unit 31, the load current characteristic calculation unit 17 calculates the long-time-limit load current characteristic and the short-time-limit load current characteristic. The user can operate the measurement start button at the start timing of the period in which the load current is in the maximum state, and cause the load current characteristic calculation unit 17 to calculate the maximum load current time limit characteristic. The load current characteristic calculation unit 17 associates the information of the calculated load current time limit characteristic with the information of the measurement period and stores the information in the storage unit 23. The storage unit 23 stores information on the overcurrent trip operation characteristic and information on the advance warning operation characteristic in addition to information on the load current time limit characteristic.

The advance warning processing unit 18 determines whether to output the advance warning to the notification unit 32 based on the load current effective value Irms. The advance warning processing unit 18 has information on advance warning operation characteristics. Specifically, the pre-alarm processing unit 18 determines whether or not the load current effective value Irms exceeds a pre-alarm threshold value defined by the pre-alarm operation characteristic. When the load current effective value Irms exceeds the pre-alarm current threshold Ip, the pre-alarm processing unit 18 outputs a pre-alarm to the notification unit 32.

The recommended value calculation unit 19 calculates a recommended value of the pre-alarm operation characteristic based on the information of the load current time limit characteristic and the information of the overcurrent trip operation characteristic. For example, the recommended value calculation unit 19 calculates the recommended value of the pre-alarm operation characteristic so as to be a characteristic intermediate between the load current time limit characteristic and the overcurrent trip operation characteristic. The recommended value calculation unit 19 causes the storage unit 23 to store the calculated recommended value of the pre-alarm operation characteristic. The electronic circuit breaker 1 may be configured without the recommended value calculation unit 19.

The output unit 20 outputs the trip signal S to the trip circuit 30 based on requests from the instantaneous trip processing unit 14, the short-time trip processing unit 15, and the long-time trip processing unit 16. The communication unit 21 performs short-range wireless communication such as Bluetooth, for example, and performs communication with the information processing apparatus 50. For example, when receiving an information transmission request, which is a transmission request of characteristic information, from the information processing apparatus 50, the communication unit 21 transmits characteristic information indicating the overcurrent trip operation characteristic, the pre-alarm operation characteristic, and the load current time limit characteristic stored in the storage unit 23 to the information processing apparatus 50.

The setting unit 22 can set the information of the overcurrent trip operation characteristic and the information of the advance warning operation characteristic based on the operation of the user to the input unit 31 or the information output from the communication unit 21. For example, the setting unit 22 sets information of a new overcurrent trip operation characteristic in the short-time trip processing unit 15 and the long-time trip processing unit 16 based on the operation of the user to the input unit 31 or the information output from the communication unit 21, and stores the information of the new overcurrent trip operation characteristic in the storage unit 23. The setting unit 22 sets information of the new pre-alarm operation characteristic in the pre-alarm processing unit 18 based on the operation of the user to the input unit 31 or the information output from the communication unit 21, and stores the information of the new pre-alarm operation characteristic in the storage unit 23.

The information processing apparatus 50 displays the received characteristic information if the characteristic information is received from the electronic circuit breaker 1. Fig. 3 is a diagram showing an example of the configuration of the information processing apparatus according to embodiment 1. Fig. 4 is a diagram showing an example of characteristic information displayed by the information processing apparatus according to embodiment 1. Fig. 5 is a diagram showing another example of characteristic information displayed by the information processing apparatus according to embodiment 1.

As shown in fig. 3, the information processing apparatus 50 has a communication section 51, a display section 52, an input section 53, a control section 54, and a storage section 55. The communication unit 51 performs short-range wireless communication such as Bluetooth, for example, and performs communication with the electronic circuit breaker 1. The display portion 52 is, for example, an LCD (Liquid CRYSTAL DISPLAY) or an organic EL (ElectroLuminescence) display. The input unit 53 includes, for example, a keyboard, a mouse, a keypad, a touch panel, or the like.

The control unit 54 causes the communication unit 51 to transmit an information transmission request, which is a transmission request of the characteristic information, to the electronic circuit breaker 1 based on a user operation to the input unit 53. The control unit 54 acquires the characteristic information transmitted from the electronic circuit breaker 1 in response to the information transmission request and received by the communication unit 51 from the communication unit 51, and stores the acquired characteristic information in the storage unit 55. Based on the user operation to the input unit 53, the control unit 54 acquires the characteristic information from the storage unit 55, and causes the display unit 52 to display the acquired characteristic information as shown in fig. 4.

The control unit 54 further includes a display processing unit 60, a setting processing unit 61, and a recommended value calculation unit 62. The display processing unit 60 obtains information for generating the characteristic information and the update image from the storage unit 55, and can cause the display unit 52 to display the update image based on the obtained information.

As shown in fig. 5, the update image 70 displayed on the display unit 52 of the information processing apparatus 50 includes a characteristic display area 71, a current setting value display area 72 indicating a current setting value, and a frame display area 73 in which a new setting value is input. The update image 70 includes a setting value change bar 74, an acquisition button 75, a recommended value calculation button 76, a recommended value setting button 77, an update button 78, and a write button 79.

In the characteristic display area 71, a pattern indicating the overcurrent trip operation characteristic, the pre-alarm operation characteristic, and the load current time limit characteristic is arranged. The current setting value display area 72 shows the current setting values of the respective characteristics, "Iu", "TL", "Is", "Ts", "Ii" and "Ip". "Iu" is a continuous energization current value, and is set In a range of, for example, 0.8 to 1.0 times the rated current In.

"TL" is a long-time trip operation time that defines an operation time in the long-time trip region. The "Is" shown In fig. 5 Is a short-time operation current threshold, which Is an overcurrent determination threshold In the short-time trip region, and Is set In a range of 1.5 to 10 times the rated current In, for example. "Ts" is a short-time trip operation time that defines an operation time in the short-time trip region. "Ii" is an overcurrent determination threshold in the instantaneous trip region. "Ip" is the pre-alarm current threshold.

The frame display area 73 includes text boxes into which new setting values of the respective characteristics can be input, and the user of the information processing apparatus 50 can input the new setting values into the respective text boxes by operating the input unit 53.

The setting value changing bar 74 is GUI (Graphical User Interface) for changing the setting of the characteristic selected by the operation to the input unit 53 among the plurality of characteristics. The user of the information processing apparatus 50 can change the set value by operating the set value changing bar 74 by operating the input unit 53.

The acquisition button 75 is a GUI button for acquiring information of load current time limit characteristics from the electronic circuit breaker 1. By operating the acquisition button 75, the user transmits a load characteristic transmission request requesting information of the load current time limit characteristic to the electronic circuit breaker 1, and acquires information of the load current time limit characteristic transmitted from the electronic circuit breaker 1 in response to the load characteristic transmission request.

The recommended value calculation button 76 is a GUI button for calculating a recommended value of the pre-alarm operation characteristic. When the recommended value calculation button 76 is operated by the user, the recommended value calculation unit 62 of the control unit 54 calculates a recommended value of the pre-alarm operation characteristic based on the information of the load current time limit characteristic and the information of the overcurrent trip operation characteristic. For example, the recommended value calculation unit 62 calculates the recommended value of the pre-alarm operation characteristic so as to be a characteristic intermediate between the load current time limit characteristic and the overcurrent trip operation characteristic. The display processing unit 60 then arranges the recommended pre-alarm operation characteristic in the characteristic display area 71 based on the recommended value of the pre-alarm operation characteristic calculated by the recommended value calculating unit 62. The display processing unit 60 may also input the recommended value of the pre-alarm operation characteristic calculated by the recommended value calculating unit 62 into the text box in the box display area 73.

The information processing apparatus 50 may be configured not to provide the recommended value calculation unit 62. In this case, the control unit 54 of the information processing apparatus 50 transmits a recommended value calculation request to the electronic circuit breaker 1, and can cause the recommended value calculation unit 19 of the electronic circuit breaker 1 to calculate a recommended value of the pre-alarm operation characteristic. The recommended value calculation unit 19 transmits the information of the recommended value of the pre-alarm operation characteristic to the information processing device 50 via the communication unit 21. The control unit 54 of the information processing apparatus 50 obtains information of the recommended value of the pre-alarm operation characteristic via the communication unit 51. The display processing unit 60 configures the recommended pre-alarm operation characteristics in the characteristics display area 71 based on the recommended value of the pre-alarm operation characteristics calculated by the electronic circuit breaker 1. The display processing unit 60 may also input the recommended value of the pre-alarm operation characteristic calculated by the electronic circuit breaker 1 into the text box in the box display area 73.

The recommended value setting button 77 is a GUI button for setting a recommended value of the pre-alarm operation characteristic as a new set value of the pre-alarm operation characteristic in the electronic circuit breaker 1. When the user operates the recommended value setting button 77, the recommended value calculation unit 62 of the control unit 54 calculates a recommended value of the pre-alarm operation characteristic. The setting processing unit 61 of the control unit 54 causes the communication unit 51 to transmit setting request information including the recommended value of the pre-alarm operation characteristic to the electronic circuit breaker 1 as a new set value of the pre-alarm operation characteristic. The setting unit 22 of the electronic circuit breaker 1 obtains the setting request information via the communication unit 21, and sets the recommended value of the advanced warning operation characteristic included in the obtained setting request information as a new set value of the advanced warning operation characteristic in the advanced warning processing unit 18.

The update button 78 is a GUI button for inputting a value corresponding to the position of the setting value change bar 74 to the text box of the box display area 73. When the user operates the update button 78, the display processing unit 60 of the control unit 54 inputs a value corresponding to the position of the setting value change bar 74 into the text box of the box display area 73.

The write button 79 is a GUI button for setting a new setting value of a text box input to the box display area 73 to the electronic circuit breaker 1. When the user operates the write button 79, the setting processing unit 61 of the control unit 54 causes the communication unit 51 to transmit setting request information including a new setting value of the text box input to the box display area 73 to the electronic circuit breaker 1. The setting unit 22 of the electronic circuit breaker 1 obtains setting request information via the communication unit 21, and sets information included in the obtained setting request information to the short-time trip processing unit 15, the long-time trip processing unit 16, and the advance warning processing unit 18.

Next, a process performed by the processing unit 10 of the electronic circuit breaker 1 will be described with reference to a flowchart. Fig. 6 is a flowchart showing an example of processing performed by the processing unit of the electronic circuit breaker according to embodiment 1, and is repeatedly executed for each processing routine time Δ Troop.

As shown in fig. 6, the processing unit 10 sets the energization time data Tx to 0 and initializes the energization time data Tx (step S10). The energization time data Tx includes data of the energization time TxP [ i ] and data of the energization time TxS [ i ] for each current level Ilevel [ i ]. "i" is an arbitrary integer from "1" to "n", and the energization time data Tx includes the data of energization times TxP [1] to TxP [ n ] and the data of energization times TxS [1] to TxS [ n ] of the current levels Ilevel [1] to [ n ].

N is the maximum value of the current level Ilevel. The maximum value of the current level Ilevel is a value obtained by dividing the maximum value of the horizontal axis of the graph shown in fig. 2 by the unit current value Imin. The unit current value Imin is the minimum unit of the value of the horizontal axis of the graph shown in fig. 2.

Next, the processing unit 10 calculates the load current effective value Irms based on the digital value output from the AD conversion unit 11 (step S11). The processing unit 10 determines whether or not the load current effective value Irms calculated in step S11 exceeds the pre-alarm current threshold Ip (step S12).

When it Is determined that the load current effective value Irms exceeds the pre-alarm current threshold Ip (Yes in step S12), the processing unit 10 determines whether or not the load current effective value Irms calculated in step S11 exceeds the short-time operation current threshold Is (step S13). When it Is determined that the load current effective value Irms exceeds the short-time operation current threshold value Is (Yes in step S13), the processing unit 10 adds the current product obtained by multiplying the processing routine time Δ Troop by the square value Is ² of the short-time operation current threshold value Is to the previous accumulated current value S2 to the current accumulated current value S1, and sets the previous accumulated current value S2 to the same value as the current accumulated current value S1 in order to perform the next processing routine (step S14).

Here, the current accumulated current value S1 will be described. Fig. 7 is a diagram showing an example of overcurrent trip operation characteristics of the electronic circuit breaker according to embodiment 1. When the load current of the load current effective value Irms1 shown in fig. 7 continuously flows during the period of time Te2, the current cumulative current value S1 is a rectangular area surrounded by a line segment from 0 to Te2 on the vertical axis and a line segment from 0 to Irms1 ² on the horizontal axis, and can be represented by s1=te2×irm1 ².

In step S13 shown in fig. 6, when it Is determined that the load current effective value Irms does not exceed the short-time operation current threshold Is (step S13: no), the processing unit 10 sets the overcurrent exceeding flag Flg to "1" (step S15). Then, the processing unit 10 adds the current product obtained by multiplying the processing routine time Δ Troop by the square value Irms ² of the load current effective value Irms to the previous accumulated current value S2 with respect to the current accumulated current value S1, and sets the previous accumulated current value S2 to the same value as the current accumulated current value S1 in order to perform the next processing routine (step S16).

When determining that the load current effective value Irms does not exceed the pre-alarm current threshold Ip (step S12: no), the processing unit 10 determines whether or not the overcurrent exceeding flag Flg is "1" (step S18). When it is determined that the overcurrent exceeding flag Flg is "1" (step S18: yes), the processing unit 10 jumps to the residual current product correction processing in step S19.

Specifically, the processing unit 10 subtracts a current product obtained by multiplying the processing routine time Δ Troop by the heat radiation coefficient P from the current accumulated current value S2 with respect to the current accumulated current value S1, and then sets the current accumulated current value S2 to the same value as the current accumulated current value S1 for the next processing routine (step S19). By subtracting the current product obtained by multiplying the processing routine time Δ Troop by the heat radiation coefficient P from the previous accumulated current value S2, when the load current effective value Irms is equal to or smaller than the previous alarm current threshold Ip, a value corresponding to cooling can be subtracted from the present accumulated current value S1. The heat dissipation coefficient P is a heat dissipation coefficient per unit time. The unit time is, for example, 1 second.

Next, the processing unit 10 determines whether or not the current accumulated current value S1 is a value smaller than "0" (step S20). When it is determined that the current accumulated current value S1 is a value smaller than "0" (step S20: yes), the processing unit 10 sets the current accumulated current value S1 and the previous accumulated current value S2 to "0" (step S21), and sets the overcurrent exceeding flag Flg to "0" (step S22).

When the process of step S14 ends or when the process of step S16 ends, the processing unit 10 determines whether or not the current integrated current value S1 is equal to or greater than a constant K (step S17). The constant K is an overcurrent determination threshold defined by a predetermined long-time trip characteristic in the overcurrent trip operation region. The long-time trip characteristic is set based on the value of "TL" shown in fig. 5. "TL" represents, for example, a long-term trip operation time In the case where a load current 2 times the rated current In flows.

In the long-term trip characteristic of fig. 7, the long-term trip operation time Te1 is represented by te1=k/Irms 1 ². The constant K is a value corresponding to the area S0 shown in fig. 7. The area S0 is a rectangular area surrounded by a line segment from 0 to Te1 on the vertical axis and a line segment from 0 to Irms1 ² on the horizontal axis. That is, the constant K is a value represented by k=s0=te1×irms1 ².

The processing unit 10 performs short-time counter processing (step S23) when it is determined that the current integrated current value S1 is not greater than or equal to the constant K (step S17: no), when it is determined that the overcurrent exceeding flag Flg is not "1" (step S18: no), when it is determined that the current integrated current value S1 is not less than the value of "0" (step S20: no), or when the processing of step S22 is completed. The short-time limit counter processing is the processing of steps S30 to S33 shown in fig. 8, which will be described later.

Next, the processing unit 10 determines whether or not the current short time limit counter STD1 is equal to or greater than the constant L (step S24). The constant L is a value defined by a short-time trip characteristic set in advance in the overcurrent trip operation region. For example, the constant L Is an overcurrent determination threshold obtained by multiplying the short-time operation current threshold Is by the short-time operation time Ts.

When the short-time trip processing unit 15 determines that the current short-time counter STD1 is not greater than or equal to the constant L (step S24: no), the processing unit 10 performs load current characteristic calculation processing (step S25), and the processing proceeds to step S11. The load current characteristic calculation process is a process of steps S40 to S44 shown in fig. 9, and will be described in detail later.

When it is determined that the current short-time counter STD1 is equal to or greater than the constant L (Yes in step S24), or when it is determined that the current accumulated value S1 is equal to or greater than the constant K (Yes in step S17), the processing unit 10 outputs the trip signal S to the trip circuit 30, sets the trip device 5 to the open state from the closed state to the open state (step S26), and ends the processing shown in fig. 6.

The processing of step S11 is performed by the effective value calculation unit 13 of the processing unit 10, and the processing of steps S12 to S22 is performed by the long-time trip processing unit 16 of the processing unit 10. The processing in steps S23 and S24 is performed by the peak value calculation unit 12 and the short-time trip processing unit 15 of the processing unit 10, and the processing in step S25 is performed by the load current characteristic calculation unit 17. The process of step S26 is performed by the output unit 20 of the processing unit 10.

Fig. 8 is a flowchart showing an example of the short-time counter processing performed by the processing unit of the electronic circuit breaker according to embodiment 1. As shown in fig. 8, the peak value calculation unit 12 of the processing unit 10 calculates the load current peak value Ipeak based on the digital value output from the AD conversion unit 11 (step S30).

Next, the short-time trip processing unit 15 of the processing unit 10 determines whether or not the load current peak value Ipeak calculated in step S30 exceeds the short-time operation current threshold Is (step S31). When it Is determined that the load current peak value Ipeak exceeds the short-time operation current threshold Is (Yes in step S31), the short-time trip processing unit 15 sets the value obtained by adding "1" to the value of the previous short-time counter STD2 to the value of the current short-time counter STD1, and sets the value of the previous short-time counter STD2 to the same value as the current short-time counter STD1 in order to perform the next processing routine (step S32).

When it Is determined that the load current peak value Ipeak does not exceed the short-time operation current threshold Is (step S31: no), the short-time trip processing unit 15 sets the value obtained by subtracting "1" from the value of the previous short-time counter STD2 to the value of the current short-time counter STD1, and sets the value of the previous short-time counter STD2 to the same value as the current short-time counter STD1 for the next processing routine (step S33). When the process of step S32 is completed, or when the process of step S33 is completed, the processing unit 10 ends the process shown in fig. 8.

Fig. 9 is a flowchart showing an example of load current characteristic calculation processing performed by the processing unit of the electronic circuit breaker according to embodiment 1. As shown in fig. 9, the load current characteristic calculation unit 17 of the processing unit 10 performs TxS update processing to obtain the energization time TxS [ i ] (step S40).

In step S40, the load current characteristic calculation unit 17 divides the current integrated current value S1 by the unit current value Imin to calculate the current level I1 level. The load current characteristic calculation unit 17 obtains information of the current accumulated current value S1 from the long-time trip processing unit 16. The load current characteristic calculation unit 17 may calculate the current accumulated current value S1 by the same operation as the long-time trip processing unit 16.

The load current characteristic calculation unit 17 calculates the energization time TxS [1] to TxS [ I1level ]. If the current level Ilevel which is less than or equal to the current level I1level is set to "x", the load current characteristic calculation unit 17 calculates the energization time TxS [ x ] by the operation of the following expression (1). "x" is an integer from "1" to "I1level", and represents a current level Ilevel.

TxS[x]=ΔTroop×S1/(x×Imin)²···(1)

Specifically, the load current characteristic calculation unit 17 divides the current accumulated current value S1 by a value obtained by multiplying each of the plurality of current levels Ilevel [1] to Ilevel [ I1level ] up to the current level I1level by the unit current value Imin, and then squares the multiplied value, thereby obtaining the values of the maximum current counters Icntm [1] to Icntm [ I1level ]. The load current characteristic calculation unit 17 multiplies the values of the maximum current counters Icntm [1] to Icntm [ I1level ] by the processing routine time Δ Troop, thereby calculating the energization times TxS [1] to TxS [ I1level ].

Since the current accumulated current value S1 is calculated based on the load current effective value Irms, the energization time TxS that matches the long-term trip region of the overcurrent trip operation characteristic can be obtained in step S40, but when the load current that is equal to or less than the pre-alarm current threshold Ip continues to flow, the process of step S19 shown in fig. 6 is performed. Therefore, when the load current equal to or smaller than the pre-alarm current threshold Ip continues to flow, the current accumulated current value S1 becomes "0", and therefore the energization time TxS [ x ] cannot be calculated. In addition, since the overcurrent trip operation is performed in the short-time trip region and the instantaneous trip region based on the load current peak value Ipeak, the energization time matching the short-time trip region and the instantaneous trip region in the trip operation characteristic is not obtained.

Therefore, the load current characteristic calculation unit 17 performs TxP update processing for obtaining the energization time TxP [ x ] using the load current peak value Ipeak (step S41). The TxP updating process is a process of steps S50 to S56 shown in fig. 10, and will be described in detail later.

Next, the load current characteristic calculation unit 17 determines whether or not the value of the energization time TxS [ x ] is larger than the value of the energization time TxP [ x ] for each current level Ilevel [ x ] (step S42). For example, the load current characteristic calculation unit 17 determines whether or not the value of the energization time TxS [1] is larger than the value of the energization time TxP [1], and determines whether or not the value of the energization time TxS [ I1level ] is larger than the value of the energization time TxP [ I1level ].

When it is determined that the value of the energization time TxS [ x ] is larger than the value of the energization time TxP [ x ] (Yes in step S42), the load current characteristic calculating unit 17 sets the value of the energization time TxS [ x ] to the value of the maximum energization time Txmax [ x ] (step S43). For example, when the value of the energization time TxS [1] is larger than the value of the energization time TxP [1], the load current characteristic calculating unit 17 sets the value of the energization time TxS [1] to the value of the maximum energization time Txmax [1 ]. When the value of the energization time TxS [ I1level ] is larger than the value of the energization time TxP [ I1level ], the load current characteristic calculating unit 17 sets the value of the energization time TxS [ I1level ] to the value of the maximum energization time Txmax [ I1level ].

When it is determined that the value of the energization time TxS [ x ] is not larger than the value of the energization time TxP [ x ] (step S42: no), the load current characteristic calculating unit 17 sets the value of the energization time TxP [ x ] to the maximum energization time Txmax [ x ] (step S44). For example, when the value of the energization time TxS [1] is not larger than the value of the energization time TxP [1], the load current characteristic calculating unit 17 sets the value of the energization time TxP [1] to the maximum energization time Txmax [1]. When the value of the energization time TxS [ I1level ] is not greater than the value of the energization time TxP [ I1level ], the load current characteristic calculating unit 17 sets the value of the energization time TxP [ I1level ] to the maximum energization time Txmax [ I1level ].

As described above, the load current characteristic calculation unit 17 uses the larger value of the current-carrying time TxS [ x ] and the current-carrying time TxP [ x ]. Thus, for example, when there is a period in which the load current periodically fluctuates and is less than or equal to the pre-alarm current threshold Ip, the energization time TxP [ x ] is used. Therefore, for example, from the standpoint of setting the reference when setting the pre-alarm operation characteristic, the load current time limit characteristic can be calculated more appropriately.

When the process of step S43 is completed or when the process of step S44 is completed, the load current characteristic calculation unit 17 stores the maximum energization time Txmax [ x ] in the storage unit 55, and updates the information of the load current time limit characteristic (step S45). When the processing in step S45 is completed, the load current characteristic calculation unit 17 ends the processing shown in fig. 9.

By repeating the above-described processing, the load current characteristic calculation unit 17 can store information of the load current time limit characteristic including information of the maximum conduction time Txmax [ n ] of each current level Ilevel in the storage unit 55.

The load current characteristic calculation unit 17 may use the energization time TxP [ k ] in the trip region at the short limit, and may use only the energization time TxS [ p ] in the trip region at the long limit and the region having a longer time than the trip region at the long limit. Further, "k" is a current level Ilevel corresponding to the short limit, and "p" is a current level corresponding to the trip region at the long limit and a region longer in time than the trip region at the long limit.

Fig. 10 is a flowchart showing an example of TxP update processing performed by the processing unit of the electronic circuit breaker according to embodiment 1. As shown in fig. 10, the load current characteristic calculation unit 17 divides the load current peak value Ipeak calculated in step S30 shown in fig. 8 by the unit current value Imin, thereby calculating the current level I1level (step S50).

For example, when the horizontal axis range In the load current characteristic is 0 to 2000% of the rated current In and the unit current value Imin is 5% In, the current level I1level range is 1 to 400. When the load current peak value Ipeak is 1000% in, the current level I1level becomes 1000% in/5% in=200. "5% In" means 5% of the rated current In, and "1000% In" means 1000% of the rated current In.

Next, the load current characteristic calculation unit 17 adds "1" to the value of the current counter Icnt [ x ] of the current level I1level, which is smaller than or equal to the current level I1level, among the current counters Icnt [1] to Icnt [ n ] (step S51). "x" shown in step S51 of fig. 10 is an integer from "1" to "I1 level". Therefore, in the process of step S51, the value of each of the current counters Icnt [1] to Icnt [ I1level ] that is smaller than or equal to the current level I1level among the current counters Icnt [1] to Icnt [ n ] is added with "1".

Next, the load current characteristic calculation unit 17 determines whether or not the previous current level I0level is greater than the current level I1level (step S52). When it is determined that the previous current level I0level is greater than the current level I1level (Yes in step S52), the processing unit 10 sets the value of the current counter Icnt having the current level Ilevel greater than the current level I1level to "0" (step S53).

Specifically, the load current characteristic calculation unit 17 sets the value of the current counter Icnt [ I1level+1] to Icnt [ I0level ] corresponding to the current level Ilevel greater than the current level I1level among the current levels Ilevel up to the previous current level I0level to "0".

Next, when the processing of step S53 is completed or when it is determined that the previous current level I0level is not greater than the current level I1level (step S52: no), the load current characteristic calculation unit 17 determines whether or not the current counter Icnt [ x ] is greater than the maximum current counter Icntm [ x ] (step S54).

"X" shown in step S54 of fig. 10 is an integer from "1" to "I1 level". Therefore, in the process of step S54, it is determined whether or not the value of each of the current counters Icnt [1] to Icnt [ I1level ] is larger than the value of the corresponding maximum current counter Icntm among the plurality of maximum current counters Icntm [1] to Icntm [ I1level ].

When it is determined that the current counter Icnt [ x ] is larger than the maximum current counter Icntm [ x ] (step S54: yes), the load current characteristic calculation unit 17 sets the maximum current counter Icntm [ x ] to the same value as the current counter Icnt [ x ] (step S55).

For example, when the current counter Icnt [1] at this time is larger than the maximum current counter Icntm [1], the load current characteristic calculation unit 17 sets the value of the maximum current counter Icntm [1] to the same value as the current counter Icnt [1 ]. Further, when the current counter Icnt [1] is not larger than the maximum current counter Icntm [1], the load current characteristic calculation unit 17 does not update the value of the maximum current counter Icntm [1 ].

When the current counter Icnt [ I1level ] is larger than the maximum current counter Icntm [ I1level ], the load current characteristic calculation unit 17 sets the value of the maximum current counter Icntm [1] to the same value as the current counter Icnt [ I1level ]. In addition, when the current counter Icnt [ I1level ] is not greater than the maximum current counter Icntm [1], the load current characteristic calculation unit 17 does not update the value of the maximum current counter Icntm [ I1level ].

Next, when the processing in step S55 is completed or when it is determined that the current counter Icnt [ x ] is not greater than the maximum current counter Icntm [ x ] (step S54: no), the load current characteristic calculation unit 17 calculates the value obtained by multiplying the value of the maximum current counter Icntm [ x ] by the processing routine time Δ Troop as the energization time TxP [ x ] (step S56).

"X" shown in step S56 of fig. 10 is an integer from "1" to "I1 level". Therefore, in the process of step S56, the load current characteristic calculation unit 17 multiplies the values of the maximum current counters Icntm [1] to Icntm [ Ilevel ] by the processing routine time Δ Troop, thereby calculating the energization times TxP [1] to TxP [ Ilevel ]. When the processing of step S56 is completed, the load current characteristic calculation unit 17 ends the processing shown in fig. 10.

Here, txP update processing and TxS update processing will be described more specifically. Fig. 11 is a diagram showing an example of load current in the case where the load according to embodiment 1 is a generator. When the load 3 is a generator, a starting current flows as shown in fig. 11. In fig. 11, the vertical axis represents an instantaneous value of the load current, and the horizontal axis represents time. In addition, each cycle of the horizontal axis shows a cycle of the processing routine time Δ Troop.

In the example shown in fig. 11, the peak value of the load current is the largest in the 1 st cycle, and then the generator accelerates up to the rated speed to reduce the peak value. Specifically, the load current shown in fig. 11 is the maximum peak value of the 1 st cycle, and 500% in. The peak value of the 5 th cycle becomes 50% in, and the peak value of the 6 th cycle and the following cycles are kept 50% in as the extreme value of the load current decreases with the lapse of time. "500% In" represents a value of 500% of the rated current In, and "50% In" represents a value of 50% of the rated current In.

The unit current value Imin is set to 50% in. In the initial state, the initial value of each current counter Icnt [ I ] is "0", the initial value of each maximum current counter Icntm [ I ] is "0", and the initial value of each previous current level I0level [ I ] is "n".

Fig. 12 is a diagram for explaining TxP updating processing in the 1 st cycle shown in fig. 11. Fig. 13 is a diagram for explaining TxP updating processing in the 2 nd cycle shown in fig. 11. Fig. 14 is a diagram for explaining TxP updating processing in the 3 rd cycle shown in fig. 11. Fig. 15 is a diagram for explaining TxP updating processing in the 4 th cycle shown in fig. 11. Fig. 16 is a diagram for explaining TxP updating processing in the 5 th cycle shown in fig. 11. Fig. 17 is a diagram for explaining TxP updating processing in the 6 th cycle shown in fig. 11. Fig. 18 is a diagram for explaining TxP updating processing in the 7 th cycle shown in fig. 11. Fig. 19 is a diagram for explaining TxP updating processing in the 99 th cycle shown in fig. 11.

In the 1 st cycle, the load current peak value Ipeak is 500% in, and therefore, in the processing of step S50 shown in fig. 10, the processing unit 10 calculates "10" as the current level I1level by the calculation of I1 level=ipeak/imin=500% in/50% in.

The current counter Icnt of the current level Ilevel smaller than or equal to the current level I1level is the current counter Icnt [1] to Icnt [10]. Therefore, in step S51 shown in fig. 10, the processing unit 10 adds "1" to the current counter Icnt [1] to Icnt [10].

In the 1 st period, the previous current level I0level is "0". In step S52 shown in fig. 10, the processing unit 10 determines that I0level > I1level is not present, and jumps the processing to step S54. In step S54 shown in fig. 10, the processing unit 10 determines whether or not the current counter Icnt [1] to Icnt [10] is larger than the corresponding maximum current counter Icntm among the maximum current counters Icntm [1] to Icntm [10 ].

In the 1 st period, the maximum current counter Icntm [1] to Icntm [10] has a value of "1". Therefore, in step S55 shown in fig. 10, the processing unit 10 sets "1" which is the value of each maximum current counter Icntm [1] to Icntm [10] to the value of the current counter Icnt corresponding to the current counters Icnt [1] to Icnt [10 ].

Next, in step S56 shown in fig. 10, the processing unit 10 multiplies the processing routine time Δ Troop by the values of the maximum current counters Icntm [1] to Icntm [10] to calculate the energization times TxP [1] to TxP [10 ]. The processing routine time Delta Troop is 20ms, so each of the power-on times TxP [1] to TxP [10] is 20ms.

Next, the processing performed by the processing unit 10 in the 2 nd cycle will be described. In the 2 nd cycle, the load current peak value Ipeak is 400% in, and therefore, in the process of step S50 shown in fig. 10, the processing unit 10 calculates the current level I1level as "8" by calculation of Ipeak/imin=400% in/50%.

The current counter Icnt of the current level Ilevel smaller than or equal to the current level I1level is the current counters Icnt [1] to Icnt [8]. Therefore, in step S51 shown in fig. 10, the processing unit 10 adds "1" to the current counter Icnt [1] to Icnt [8]. Since the previous current level I0level is "10", the processing unit 10 sets the current counters Icnt [9], icnt [10] to "0" in the processing of step S53 shown in fig. 10.

In step S54 shown in fig. 10, the processing unit 10 determines whether or not the current counter Icnt [1] to Icnt [8] is larger than the corresponding maximum current counter Icntm among the maximum current counters Icntm [1] to Icntm [8 ]. The current counter Icnt 1-Icnt 8 has a value of "2" greater than the maximum current counter Icntm [1] to Icntm [8 ]. Therefore, in step S55 shown in fig. 10, the processing unit 10 sets "2" which is the value of each maximum current counter Icntm [1] to Icntm [8] to the value of the current counter Icnt corresponding to the current counters Icnt [1] to Icnt [8 ].

As shown in fig. 15 to 19, the processing unit 10 performs the same processing as the 1 st and 2 nd cycles for each of the 3 rd to 99 th cycles, and calculates the energization time TxP [1] to TxP [10]. Thus, the processing unit 10 can calculate the energization time TxP that matches the load current peak value Ipeak.

Next, txS update processing will be described. Fig. 20 is a diagram for explaining TxS update processing in the 1 st and 2 nd periods shown in fig. 11. Fig. 21 is a diagram for explaining TxS update processing in the 3 rd and 4 th cycles shown in fig. 11. Fig. 22 is a diagram for explaining TxS update processing in the 5 th and 6 th cycles shown in fig. 11. Fig. 23 is a diagram for explaining TxS update processing in the 7 th cycle and 99 th cycle shown in fig. 11.

In the TxS update process shown in fig. 9, the processing unit 10 divides the current accumulated current value S1 by a value obtained by multiplying each of the plurality of current levels Ilevel up to the current level I1level by the unit current value Imin, and then obtains the value of each maximum current counter Icntm [ x ]. In the following, the unit current value Imin is set to 50% in.

In the example shown in fig. 20, in the 1 st cycle, the load current effective value Irms is 500% in, and the previous accumulated current value S2 is 0. Therefore, the current level I1level is 500% in/50% in=10, and the current integrated current value S1 is Irms ²×ΔTroop＝500² ×0.02=5000.

Since the current counter Icnt [1] has a value of 5000++1×50 ] ² =2, the value of the maximum current counter Icntm [1] calculated by the processing unit 10 is "2" as shown in fig. 20. Since the current counter Icnt [2] is 5000/v (2×50) ² =0.5, the value of the maximum current counter Icntm [2] calculated by the processing unit 10 is "1" as shown in fig. 20.

Since the current counter Icnt [3] is 5000/3×50 ² =0.2, the maximum current counter Icntm [3] calculated by the processing unit 10 is "0" by rounding. Similarly, the values of the maximum current counters Icntm [4] to Icntm [10] calculated by the processing unit 10 are also "0" as shown in fig. 20.

In the TxS update process shown in fig. 9, the processing unit 10 multiplies the values of the maximum current counters Icntm [1] to [10] by the processing routine time Δ Troop, thereby calculating the energization times TxS [1] to TxS [10 ]. The energization time TxS [1] is Icntm [1] ×Δ Troop =2×20=40 [ ms ]. The energization time TxS 2 is Icntm [2] ×Δ Troop =1×20=20 [ ms ]. In addition, the energization time TxS 3 to TxS 10 is 0 ms.

In the example shown in fig. 20, the load current effective value Irms is 400% in the 2 nd cycle. Therefore, the current level I1level is 400% in/50% in=8, and the current accumulated current value S1 is s2+irms ²×ΔTroop＝5000+400² ×0.02=8200.

Since the current counter Icnt [1] has a value of 8200/1×50 ² =3.28, the value of the maximum current counter Icntm [1] calculated by the processing unit 10 is "3" as shown in fig. 20. Since the current counter Icnt [2] is 8200/² =0.82, the value of the maximum current counter Icntm [2] calculated by the processing unit 10 is "1" by rounding off the value, as shown in fig. 20.

Since the current counter Icnt [3] is 8200/² =0.36, the maximum current counter Icntm [3] calculated by the processing unit 10 is "0" by rounding off the current counter as shown in fig. 20. Similarly, the values of the maximum current counters Icntm [4] to Icntm [10] calculated by the processing unit 10 are also "0" as shown in fig. 20.

The processing unit 10 multiplies the values of the maximum current counters Icntm [1] to [10] by the processing routine time Δ Troop, thereby calculating the energization times TxS [1] to TxS [10 ]. The energization time TxS [1] is Icntm [1] ×Δ Troop =3×20=60 [ ms ]. The energization time TxS 2 is Icntm [2] ×Δ Troop =2×20=20 [ ms ]. In addition, the energization time TxS 3 to TxS 10 is 0ms.

As shown in fig. 21 to 23, the processing unit 10 performs the same processing as the 1 st and 2 nd cycles also for each cycle from the 3 rd cycle to the 99 th cycle, and calculates the energization times TxS [1] to TxS [10]. In this way, the processing unit 10 can calculate the energization time TxS that matches the load current effective value Irms.

Fig. 24 is a diagram showing an example of a hardware configuration of a processing unit of the electronic circuit breaker according to embodiment 1. As shown in fig. 24, the processing unit 10 of the electronic circuit breaker 1 includes a computer having a processor 101, a memory 102, an AD converter 103, an input/output interface 104, and a communication device 105.

The processor 101, the memory 102, the AD converter 103, the input/output interface 104, and the communication device 105 can, for example, transmit and receive data to and from each other via the bus 106. The AD converter 11 is implemented by an AD converter 103. The communication unit 21 is realized by a communication device 105. The output unit 20 is realized by an input/output interface 104. The processor 101 reads and executes a program stored in the memory 102, thereby executing the functions of the peak value calculation unit 12, the effective value calculation unit 13, the instantaneous trip processing unit 14, the short-time trip processing unit 15, the long-time trip processing unit 16, the load current characteristic calculation unit 17, the pre-alarm processing unit 18, the recommended value calculation unit 19, and the setting unit 22. The Processor 101 is an example of a processing circuit, and includes one or more of CPU (Central Processing Unit), DSP (DIGITAL SIGNAL Processor), and system LSI (LARGE SCALE Integration).

The memory 102 includes one or more of RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), and EEPROM (registered trademark) (ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY). In addition, the memory 102 contains a recording medium in which a computer-readable program is recorded. The recording medium includes one or more of nonvolatile or volatile semiconductor memory, magnetic disk, flexible memory, optical disk, compact disk, and DVD (Digital Versatile Disc). The electronic Circuit breaker 1 may include integrated circuits such as an ASIC (Application SPECIFIC INTEGRATED Circuit) and an FPGA (Field Programmable GATE ARRAY).

The control unit 54 of the information processing apparatus 50 is configured by a processor 101, a memory 102, an AD converter 103, an input/output interface 104, and a bus 106 shown in fig. 24. The processor 101 reads and executes a program stored in the memory 102, thereby executing the functions of the display processing unit 60, the setting processing unit 61, and the recommended value calculation unit 62.

As described above, the electronic circuit breaker 1 according to embodiment 1 includes the opening/closing contact 4, the trip device 5, the current detection unit 7, the peak value calculation unit 12, the effective value calculation unit 13, the short-time trip processing unit 15, the long-time trip processing unit 16, the load current characteristic calculation unit 17, and the output unit 20. The opening/closing contact 4 opens/closes a circuit 6 between the power supply 2 and the load 3. The trip device 5 sets the opening/closing contact 4 from the closed state to the open state. The current detection unit 7 detects a current flowing through the circuit 6. The peak value calculation unit 12 calculates a load current peak value Ipeak, which is a peak value of the current detected by the current detection unit 7. The effective value calculating unit 13 calculates a load current effective value Irms, which is an effective value of the current detected by the current detecting unit 7. When it is determined that the current flows through the circuit 6 in the short-time-limit region based on the load current peak value Ipeak, the short-time trip processing unit 15 causes the trip device 5 to set the open/close contact 4 to the open state from the closed state. The long-time trip processing unit 16 sets the trip device 5 to the open state from the closed state to the open state when it is determined that the current flows through the circuit 6 in the long-time range, which is the time limit longer than the short-time limit, based on the load current effective value Irms. The load current characteristic calculation unit 17 calculates a short-time-period load current characteristic, which is a current characteristic of the load 3 in the short-time-period region, based on the load current peak value Ipeak, and calculates a long-time-period load current characteristic, which is a current characteristic of the load 3 in the long-time-period region, based on the load current effective value Irms. The output unit 20 outputs information of the load current time limit characteristics including the short-time limit load current characteristic and the long-time limit load current characteristic calculated by the load current characteristic calculation unit 17. Accordingly, the electronic circuit breaker 1 can present the load current time limit characteristic that matches the overcurrent trip operation characteristic to the user, and thus the user can appropriately perform the overcurrent trip operation characteristic.

The load current characteristic calculation unit 17 calculates a long-term load current characteristic based on the load current effective value Irms and the load current peak value Ipeak. Thus, the electronic circuit breaker 1 can calculate the long-time-limit load current characteristic with high accuracy.

The electronic circuit breaker 1 further includes a pre-alarm processing unit 18 and a recommended value calculation unit 19. The pre-alarm processing unit 18 determines whether or not a pre-alarm is necessary based on a pre-alarm current threshold Ip, which is a threshold lower than an overcurrent determination threshold defined by the overcurrent trip operation characteristic, and a predetermined pre-alarm operation characteristic. The recommended value calculation unit 19 calculates a recommended value of the pre-alarm operation characteristic based on the information of the load current time limit characteristic and the information of the overcurrent trip operation characteristic. Thus, in the electronic circuit breaker 1, the user can appropriately perform the pre-alarm operation characteristic.

The circuit breaker system 100 according to embodiment 1 includes the electronic circuit breaker 1 and the information processing apparatus 50 communicably connected to the electronic circuit breaker 1. The electronic circuit breaker 1 includes a pre-alarm processing unit 18 that determines whether or not a pre-alarm is necessary based on a pre-alarm current threshold Ip, which is a threshold value lower than an overcurrent determination threshold defined by the overcurrent tripping operation characteristic, and a predetermined pre-alarm operation characteristic. The information processing apparatus 50 has a communication section 51 and a recommended value calculation section 62. The communication unit 51 receives information on the load current time limit characteristic and information on the overcurrent trip operation characteristic from the electronic circuit breaker 1. The recommended value calculation unit 62 calculates a recommended value of the pre-alarm current threshold Ip based on the information of the load current time limit characteristic and the information of the overcurrent trip operation characteristic received by the communication unit 51. Thus, in the circuit breaker system 100, the user can appropriately perform the pre-alarm operation characteristic.

The communication unit 51 transmits recommended value information including the information of the recommended value of the pre-alarm current threshold Ip calculated by the recommended value calculation unit 62 to the electronic circuit breaker 1. The electronic circuit breaker 1 includes a setting unit 22 that sets information on the pre-alarm operation characteristic in the pre-alarm processing unit 18 based on recommended value information transmitted from the information processing device 50. Thus, in the circuit breaker system 100, the user can appropriately perform the pre-alarm operation characteristic.

The communication unit 51 transmits recommended value information including the information of the recommended value of the pre-alarm current threshold Ip calculated by the recommended value calculation unit 62 to the electronic circuit breaker 1. The electronic circuit breaker 1 has an input unit 31 having a dial for setting information of the advance warning operation characteristic in the advance warning processing unit 18. Thus, in the circuit breaker system 100, the user can appropriately perform the pre-alarm operation characteristic.

The configuration shown in the above embodiment shows an example of the content of the present invention, and other known techniques may be combined, and a part of the configuration may be omitted or changed without departing from the scope of the present invention.

Description of the reference numerals

An electronic circuit breaker, a2 power supply, a3 load, 4 ₁、4₂、4₃ switching contacts, a5 trip device, 6 ₁、6₂、6₃ circuits, a 7 current detection part, a 9 voltage conversion part, a 10 processing part, an 11AD conversion part, a 12 peak value calculation part, a13 effective value calculation part, a 14 instantaneous trip processing part, a 15 short-time trip processing part, a 16 long-time trip processing part, a 17 load current characteristic calculation part, an 18 pre-alarm processing part, a 19, 62 recommended value calculation part, a 20 output part, a 21, 51 communication part, a 22 setting part, a 30 trip circuit, a 31, 53 input part, a 32 notification part, a 50 information processing device, a52 display part, a 54 control part, a 55 storage part, a 60 display processing part, a 61 setting processing part, and a 100 circuit breaker system.

Claims (5)

1. An electronic circuit breaker is disclosed, characterized by comprising:

an opening/closing contact for opening/closing a circuit between a power source and a load;

A trip device for setting the opening/closing contact from a closed state to an open state;

a current detection unit that detects a current flowing through the circuit;

a peak value calculation unit that calculates a peak value of the current detected by the current detection unit;

an effective value calculation unit that calculates an effective value of the current detected by the current detection unit;

a short-time trip processing unit that causes the trip device to set the open/close contact point from a closed state to an open state when it is determined that an overcurrent flows in the circuit in a short-time limit region based on the peak value calculated by the peak value calculating unit;

a long-time trip processing unit that, when it is determined that an overcurrent flows in the circuit in a region longer than a time limit of the short-time limit, that is, a long-time limit, based on the effective value calculated by the effective value calculating unit, causes the trip device to set the open/close contact point to an open state from a closed state;

a load current characteristic calculation unit that calculates a short-time-period load current characteristic, which is a current characteristic of the load in the short-time-period region, based on the peak value calculated by the peak value calculation unit, and calculates a long-time-period load current characteristic, which is a current characteristic of the load in the long-time-period region, based on the effective value calculated by the effective value calculation unit;

an output unit that outputs information including the short-time-limit load current characteristic calculated by the load current characteristic calculation unit and the long-time-limit load current characteristic,

A pre-alarm processing unit that determines whether or not a pre-alarm is necessary based on a pre-alarm operation characteristic that defines a pre-alarm current threshold value that is lower than an overcurrent determination threshold value defined by an overcurrent trip operation characteristic including detection characteristics of the overcurrent of each of the short-time trip processing unit and the long-time trip processing unit, and

A recommended value calculation unit that calculates a recommended value of the pre-alarm operation characteristic based on the information of the load current time limit characteristic and the information of the overcurrent trip operation characteristic,

The output unit outputs the recommended value calculated by the recommended value calculation unit.

2. The electronic circuit breaker according to claim 1, characterized in that,

The load current characteristic calculation unit calculates the long-term load current characteristic based on the effective value calculated by the effective value calculation unit and the peak value calculated by the peak value calculation unit.

3. A circuit breaker system, having:

An electronic circuit breaker as claimed in claim 1 or 2, and

An information processing device communicably connected to the electronic circuit breaker,

The electronic circuit breaker includes a pre-alarm processing unit that determines whether or not a pre-alarm is necessary based on a pre-alarm operation characteristic that defines a pre-alarm current threshold value that is lower than an overcurrent determination threshold value defined by an overcurrent trip operation characteristic including detection characteristics of the overcurrent of each of the short-limit time trip processing unit and the long-limit time trip processing unit,

The information processing device includes:

A communication part for receiving the information of the load current time limit characteristic and the information of the overcurrent trip operation characteristic from the electronic circuit breaker, and

And a recommended value calculation unit that calculates a recommended value of the pre-alarm current threshold value based on the information of the load current time limit characteristic and the information of the overcurrent trip operation characteristic received by the communication unit.

4. A circuit breaker system according to claim 3 wherein,

The communication unit transmits recommended value information including the information of the recommended value of the pre-alarm current threshold calculated by the recommended value calculation unit to the electronic circuit breaker,

The electronic circuit breaker includes a setting unit that sets the information of the advance warning operation characteristic to the advance warning processing unit based on the recommended value information transmitted from the information processing device.

5. A circuit breaker system according to claim 3 wherein,

The communication unit transmits recommended value information including the information of the recommended value of the pre-alarm current threshold calculated by the recommended value calculation unit to the electronic circuit breaker,

The electronic circuit breaker has an input unit having a dial for setting information of the advance warning operation characteristic to the advance warning processing unit.