CN106786373A - Power system electricity capacity safety governor - Google Patents

Abstract

The invention discloses a capacity safety controller for a power system, which includes current transformers sequentially connected in three-phase power lines, the output terminals of the current transformers are electrically connected to main current relays, and the main current relays of the three main current relays are The first end of the open output switch is electrically connected to the live wire, and the second end of the main normally open output switch is electrically connected to the neutral line through the coil of the first time relay; the first delay normally open switch of the first time relay passes through the first The branches are connected in parallel between the live wire and the neutral wire, and the first intermediate relay is also connected in series on the first branch; it also includes a second branch connected in parallel between the live wire and the neutral wire. It can monitor the power consumption in real time, and can automatically implement prompts or compulsory measures such as sending out warning signals or power failure and shutdown when the user's power consumption causes the transformer to be fully loaded or overloaded.

Description

Electric capacity safety controller for power system

technical field

The invention relates to a power capacity safety controller for a power system.

technical background

At present, when my country's industrial electricity is connected to the factory, the power supply company determines the transformer and its capacity specifications that meet the specified requirements according to the electricity consumption. The calculation method of industrial electricity charges is to determine the billing base based on the capacity of the connected transformer, and then convert it into electricity charges based on the actual electricity consumption. In actual operation, it is found that some industrial users increase production capacity and power consumption in pursuit of benefits, causing transformers to operate at full load or overload, ignoring safe production, and bringing many safety risks and hidden dangers:

1. Power grid security operation risk. Due to the variety of electrical equipment manufacturers and uneven production levels, some products do not meet the standard requirements. After they are put into operation, if they are operated with long-term overload, it will bring hidden dangers to power production and personnel safety.

2. Breach of electricity risk. After the expansion of the power industry market, some equipment manufacturers and construction units have changed the capacity of equipment privately in order to pursue profits and evade large-scale industrial electricity charges, seriously violating the "Power Supply Business Rules" and the "Electricity Law of the People's Republic of China", disrupting the safe supply and use of electricity market order.

Contents of the invention

In order to solve the above technical problems, the present invention provides a transformer with reasonable structure, convenient installation, automatic operation without manual intervention, real-time monitoring of power consumption, and automatic warning when the transformer is fully loaded or overloaded due to the user's electricity consumption. It is a power system power capacity safety controller that effectively guarantees power safety and production safety, such as signal or power outage and shutdown and other prompt measures or compulsory measures.

In order to achieve the above purpose, the structural characteristics of the electric capacity safety controller for the power system are as follows: it includes current transformers sequentially connected in the three-phase power lines, the output terminals of the current transformers are electrically connected to the main current relay, and the three main current The first end of the main normally open output switch of the relay is electrically connected to the live wire, and the second end of the main normally open output switch is electrically connected to the neutral line through the coil of the first time relay; the first time delay of the first time relay is normally open The switch is connected in parallel between the live wire and the neutral wire through the first branch, and the first intermediate relay is also connected in series on the first branch; it also includes a second branch connected in parallel between the live wire and the neutral wire, and the second branch is connected in series The first intermediate normally open switch with the second time relay and the first intermediate relay; between the connection point of the first delay normally open switch and the first intermediate relay and the connection point of the first intermediate normally open switch and the second time relay The first short circuit is electrically connected, and the second delay normally closed switch of the second time relay is connected in series on the first branch between the first intermediate relay and the neutral line; the second end of the main normally open output switch is also passed through the second terminal The three branches are electrically connected to the neutral line, the third branch includes the fifth time relay connected in series, the fifth time-delay normally closed switch of the fifth time relay, and the contactors are connected in series on the three-phase power line. Contact the normally open switch, the contactor is connected in series between the live line and the neutral line through the fourth branch, the fourth branch includes the first intermediate normally closed switch of the first intermediate relay connected in series and the second intermediate of the second intermediate relay A normally closed switch, the third branch is also connected in series with a contact auxiliary switch of a contactor; a fifth branch is connected in parallel between the live line and the neutral line, and the fifth branch includes a third intermediate relay connected in series and the fifth delay normally open switch of the fifth time relay; the third intermediate normally open switch of the third intermediate relay is connected in parallel between the first end and the second end of the main normally open output switch; An alarm branch is connected in parallel, and the alarm branch includes a third intermediate normally open switch and an alarm connected in series with the third intermediate relay.

This patent realizes the convenience of installation through the series induction and control structure, without manual intervention, automatic operation, real-time monitoring of power consumption, and automatic implementation of warning signals or alarms when the transformer is fully loaded or overloaded due to the user's electricity consumption. Prompt measures or compulsory measures such as power outages and work stoppages can effectively guarantee the safety of electricity use and production safety.

The series induction and control structure mainly includes contactors, current transformers, main current relays and other auxiliary circuits installed on the three-phase power line. Wherein, the three-phase power line is three power lines in the three-phase four-wire system power supply circuit, and also includes a neutral line. In this patent, the a-phase power line (commonly known as live line A) and the neutral line (ie N line) of the three-phase power line are selected as the auxiliary power supply of the auxiliary circuit.

In this patent, a contact normally open switch of a contactor is connected in series on the three-phase power line, and the coil of the contactor is connected in series between the live line and the neutral line of the above-mentioned auxiliary power supply through the fourth branch. Therefore, as long as the on-off of the fourth branch can be controlled, the power gain and loss of the contactor coil can be controlled, that is, the on-off of the three-phase power line can be controlled, and the power cut off for industrial full-load or overloaded power users can be realized. . In this patent, there are at least three current transformers, which are sequentially connected in series in the three-phase power lines. Therefore, the function of each current transformer is to monitor the current signal of its phase in real time, and convert the current signal into a corresponding smaller value current signal. The output end of each current transformer is correspondingly connected to a main current relay, therefore, the current transformer supplies power to the main current relay, and the main current relay collects the induced current signal of the three-phase power line from the current transformer, and uses it as its Judgment basis for the output action. The three main current relays all have a main normally open output switch, and the main normally open output switch has two output terminals, which are called the first terminal and the second terminal respectively for the convenience of description. In this patent, the first ends of the three main normally open output switches are shorted together, and the second ends of the three main normally open output switches are all shorted together. Therefore, the three main normally open output switches are connected in parallel and form a "parallel switch group".

In this patent, the first end of the parallel switch group is electrically connected to the live wire, and the second end of the parallel switch group is electrically connected to the neutral line through the third branch, and the third branch includes the fifth time relay connected in series , The fifth delay normally closed switch of the fifth time relay, and the contact auxiliary switch of the contactor. Therefore, when the user is running at full load or overload, as long as the current of one phase exceeds the standard, the parallel switch group will be closed, the power supply circuit of the fifth time relay will be connected, and the fifth time relay will act.

In this patent, a fifth branch is connected in parallel between the live line and the neutral line, and the fifth branch includes the third intermediate relay and the fifth delay normally open switch of the fifth time relay connected in series. When the fifth time relay acts, the power supply circuit of the third intermediate relay is connected, and the third intermediate relay acts.

An alarm branch is also connected in parallel between the live wire and the neutral line, and the alarm branch includes a third intermediate normally open switch and an alarm connected in series with the third intermediate relay. Therefore, after the action of the third intermediate relay, the power supply circuit of the alarm is connected, and the alarm starts to alarm.

After the delay time arrives, the relay action resumes at the fifth time.

In this patent, the delay time can be set for the fifth time relay. This delay time is the alarm time given by this patent to industrial users, that is to say, the longer this delay time is, the longer the time for this patent to alarm the user, which plays a better role in reminding and warning. The fifth delay normally closed switch of the fifth time relay is connected in series in the third branch, therefore, after the above-mentioned delay time arrives, that is, after the alarm duration arrives, the fifth delay normally closed switch will be disconnected, and the fifth delay normally closed switch will be disconnected. The time relay loses power, causing the third intermediate relay to lose power, the third intermediate normally open switch returns to the normally open state, the alarm power supply circuit is cut off, and the alarm ends.

In this patent, the third intermediate normally open switch of the third intermediate relay is connected in parallel between the first terminal and the second terminal of the main normally open output switch. The main function of this setting is to implement self-locking on the fifth time relay and the third intermediate relay within the alarm period, so as to ensure that the alarm will not automatically stop the alarm due to the recovery of the phase current within the alarm period, and strengthen the influence of the alarm role.

If the user fails to take effective measures to reduce the power consumption load after hearing the alarm signal, which affects the safety of power consumption and production safety, then this patent also has the function of forced power failure. In this patent, the first end of the parallel switch group is electrically connected to the live wire of the aforementioned auxiliary power supply, and the second end of the parallel switch group is electrically connected to the neutral wire through the coil of the first time relay. This constitutes a complete control loop, referred to as the first loop. Obviously, as long as one phase of the three-phase power line is fully loaded or overloaded, the corresponding main normally open output switch will be closed, and the relay coil will be energized at the first time. action. The delay time is to allow recovery time for the full load or overload operation reset of the factory electricity, that is to say, if the large current phenomenon is caused by accidental factors such as unstable operation of the equipment, within the set delay time, the current It will return to normal soon, and the relay will not act at the first time; if the equipment is indeed running at full load or overload, it is impossible to restore normal operation in a short period of time, that is, within the delay time mentioned above, and the relay will not operate at the first time. The control action will be output.

In this patent, the first delay normally open switch of the first time relay is connected in parallel between the live line and the neutral line through the first branch, and the first intermediate relay is also connected in series on the first branch. Therefore, when the first time relay operates, the first time delay normally open switch will be closed, the power supply circuit of the first intermediate relay will be connected, and the first intermediate relay will act. In this patent, it also includes a second branch connected in parallel between the live line and the neutral line, and the second time relay and the first intermediate normally open switch of the first intermediate relay are connected in series on the second branch. When the first intermediate relay acts, the first intermediate normally open switch is closed, therefore, the power supply circuit of the second time relay is connected, and the second time relay will act. In this patent, a first short circuit is electrically connected between the connection point of the first delay normally open switch and the first intermediate relay and the connection point of the first intermediate normally open switch and the second time relay, and the first short circuit is The self-locking of the first intermediate relay provides the condition. As mentioned above, when the first intermediate normally open switch is closed, the power supply circuit of the first intermediate relay also forms a self-locking function. One of the self-locking functions of the first intermediate relay is that after the first intermediate relay operates, even if the three-phase When the current of the power line returns to normal, the action output of the first intermediate relay will not be affected, and the first intermediate relay will still perform the output action.

As mentioned above, as long as the fourth branch is controlled, the cut-off of the industrial user's power supply can be controlled. Because the first intermediate normally-closed switch of the first intermediate relay is connected in series in the fourth branch, the action output of the first intermediate relay can realize the disconnection of the first intermediate normally-closed switch, that is, realize the power supply of industrial users. resection. This is the second self-locking function of the first intermediate relay, which is to control the removal of the power supply of industrial users.

In this patent, the second delay normally closed switch of the second time relay is connected in series on the first branch between the first intermediate relay and the neutral line. The delay time is the maintenance time for industrial users to cut off the power supply, that is, the power failure time, which can be set. When the specified power failure time expires, the second time relay will act and output, and its second time delay normally closed switch will be disconnected. As a result, the self-locking of the first intermediate relay is cut off, the first intermediate relay loses power, and the first intermediate normally closed switch is closed. As a result, the power supply circuit of the contactor is connected, the contactor starts to output, the three-phase power line is connected, and the industrial users resume power supply.

As an improvement, this patent also includes a timing branch connected in parallel between the live wire and the neutral wire, and a timing clock is connected in series on the timing branch; it also includes a secondary current relay connected in turn at the output end of the current transformer, and the secondary current relays of the three secondary current relays. The first end of the normally open output switch is electrically connected to the live wire, and the second end of the auxiliary normally open output switch is electrically connected to the neutral line through the series branch formed by the third time relay and the timing normally open switch of the fixed clock; the third time The third delay normally open switch of the relay is connected in parallel between the live wire and the neutral wire through the sixth branch, and the second intermediate relay is connected in series on the sixth branch; it also includes the seventh branch connected in parallel between the live wire and the neutral wire , the seventh branch is connected in series with the second intermediate normally open switch of the fourth time relay and the second intermediate relay; the connection point of the third delay normally open switch and the second intermediate relay is connected with the second intermediate normally open switch and the fourth The connection points of the time relays are electrically connected with a second short wire, and the fourth delay normally closed switch of the fourth time relay is connected in series on the sixth branch between the second intermediate relay and the neutral line.

This patent also includes a timing branch with a timing function, which is also connected in parallel between the live wire and the neutral wire, and a timing clock is connected in series on the timing branch. The main function of the fixed clock is to limit the time period for power supply to enterprises, so that enterprises can carry out orderly power consumption and orderly production according to the overall power consumption planning and peak and valley periods of power consumption. The setting of the fixed clock can be set according to the power supply situation on the spot, such as setting by month or setting as night power consumption and so on. The main function of this setting is to reasonably allocate power consumption, improve power consumption efficiency and ensure power supply. This patent also includes auxiliary current relays connected in sequence to the output terminals of the three current transformers, the first ends of the auxiliary normally open output switches of the three auxiliary current relays are shorted together, and the second ends of the auxiliary normally open output switches are also shorted Together, therefore, the three auxiliary normally open output switches are connected in parallel, and constitute a "parallel switch group" similar to the aforementioned "parallel switch group". The first end of the parallel switch group is electrically connected to the fire wire, and the second end of the parallel switch group is electrically connected to the neutral line through a series branch, and the series branch includes a third time relay and a fixed clock connected in series. Regularly open the switch. Because the timing clock is directly connected in parallel between the live wire and the neutral wire, as long as the contactor is in the closed state, the power supply circuit of the timing clock must be connected, and the timing normally open switch must also be closed. Therefore, the power supply of the third time relay The circuit must be connected. After the delay time of the third time relay reaches, the third time relay will act.

The delay time is to allow recovery time for the full load or overload operation reset of the factory electricity, that is to say, if the large current phenomenon is caused by accidental factors such as unstable operation of the equipment, within the set delay time, the current It will return to normal soon, and the third time relay will not act; if the equipment is indeed running at full load or overload, it is impossible to restore normal operation in a short time, that is, within the above delay time, then the third time relay The control action will be output.

In this patent, the third delay normally open switch of the third time relay is connected in parallel between the live wire and the neutral wire through the sixth branch, and the second intermediate relay is also connected in series on the sixth branch. Therefore, when the third time relay acts, the third time delay normally open switch will be closed, the power supply circuit of the second intermediate relay will be connected, and the second intermediate relay will act. In this patent, it also includes a seventh branch connected in parallel between the live line and the neutral line, and the fourth time relay and the second intermediate normally open switch of the second intermediate relay are connected in series on the seventh branch. When the second intermediate relay acts, the second intermediate normally open switch is closed, therefore, the power supply circuit of the fourth time relay is connected, and the fourth time relay will act. In this patent, there is a second short wire electrically connected between the connection point of the third delay normally open switch and the second intermediate relay and the connection point of the second intermediate normally open switch and the fourth time relay, and the second short wire is The self-locking of the second intermediate relay provides the conditions. As mentioned above, when the third intermediate normally open switch is closed, the power supply circuit of the second intermediate relay also constitutes a self-locking. One of the self-locking functions of the second intermediate relay is that after the second intermediate relay operates, even if the current of the three-phase power line returns to normal, the operation output of the second intermediate relay will not be affected, and the second intermediate relay will still perform the output action.

As mentioned above, as long as the fourth branch is controlled, the cut-off of the industrial user's power supply can be controlled. Because the second intermediate normally-closed switch of the second intermediate relay is connected in series in the fourth branch, the action output of the second intermediate relay can realize the disconnection of the second intermediate normally-closed switch, that is, realize the power supply of industrial users. resection. This is the second self-locking function of the second intermediate relay, that is, to control and cut off the power supply of industrial users.

In this patent, the fourth delay normally closed switch of the fourth time relay is connected in series on the sixth branch between the second intermediate relay and the neutral line. The delay time is the maintenance time for industrial users to cut off the power supply, that is, the power failure time, which can be set. When the prescribed power failure time expires, the fourth time relay will act and output, and its fourth time delay normally closed switch will be disconnected. As a result, the self-locking of the second intermediate relay is cut off, the second intermediate relay loses power, and the second intermediate normally closed switch is closed. As a result, the power supply circuit of the contactor is connected, the contactor starts to output, the three-phase power line is connected, and the industrial users resume power supply.

As a further improvement, an arrears normally closed switch for controlling the output of the watt-hour meter is connected in series in the fourth branch.

After the arrears normally closed switch of the control output of the watt-hour meter is connected in series in the fourth branch, when the user is in arrears of electricity charges, the control signal of the watt-hour meter can directly cut off the power supply circuit of the contactor, resulting in the disconnection of the three-phase power line. Electricity, that is to say, the function of compulsory power outage for arrears has been realized.

As a further improvement, a normally closed release button is connected in series on the third branch.

After the release button of the normally closed form is connected in series on the third branch, if the industrial user knows the full load or overload situation and is dealing with it, he can press the release button, so that the alarm will no longer alarm, avoiding interference, very humane change.

To sum up, the present invention has reasonable structure, convenient installation, automatic operation without manual intervention, real-time monitoring of power consumption, and can automatically send out warning signals or shut down when the transformer is fully loaded or overloaded due to power consumption by the user. And other reminder measures or compulsory measures to effectively guarantee the safety of electricity use and production safety.

Description of drawings

The invention will be described in further detail below in conjunction with the accompanying drawings.

Fig. 1 is a logic circuit schematic diagram of the present invention;

Figure 2 is a schematic diagram of the connection structure between the contactor and the three-phase power line;

Fig. 3 is a schematic diagram of the connection structure of the current transformer and the main/subsidiary current relay.

detailed description

As shown in the figure, the capacity safety controller for the power system includes current transformers BHa, BHb, and BHc connected in sequence to the three-phase power lines a, b, and c, and the output terminals of the current transformers are electrically connected to the main current Relays KC1, KC2, KC3, the first ends of the main normally open output switches KC1-1, KC2-1, KC3-1 of the three main current relays are all electrically connected to the fire wire A, and the second end of the main normally open output switch passes through The coil of the first time relay KT1 is electrically connected to the neutral wire N; the first delay normally open switch KT1-1 of the first time relay is connected in parallel between the live wire and the neutral wire through the first branch, and the first branch is also connected in series There is a first intermediate relay KA1. This patent also includes a second branch connected in parallel between the live wire and the neutral wire, the second time relay KT2 and the first intermediate normally open switch KA1-1 of the first intermediate relay are connected in series on the second branch; the first time delay The connection point between the normally open switch and the first intermediate relay and the connection point between the first intermediate normally open switch and the second time relay is electrically connected with a first short line DJX1, the first branch between the first intermediate relay and the neutral line The second delay normally closed switch KT2-2 of the second time relay is connected in series on the road. The second end of the main normally open output switch is also electrically connected to the neutral line through the third branch, and the third branch includes the fifth time relay KT5 connected in series, and the fifth delay normally closed switch of the fifth time relay KT5-2, the three-phase power line is sequentially connected in series with the contact normally open switches KM-1, KM-2, KM-3 of the contactor KM. The contactor is connected in series between the live line and the neutral line through the fourth branch, and the fourth branch includes the first intermediate normally closed switch KA1-2 of the first intermediate relay KA1 connected in series and the second intermediate normally closed switch of the second intermediate relay. Close switch KA2-2. A contact auxiliary switch KM-0 of the contactor is also connected in series in the third branch. A fifth branch is also connected in parallel between the live wire and the neutral wire, and the fifth branch includes the third intermediate relay KA3 connected in series and the fifth time-delayed normally-open switch KT5-1 of the fifth time relay KT5. The third intermediate normally open switch KA3-1 of the third intermediate relay is connected in parallel between the first terminal and the second terminal of the main normally open output switch. An alarm branch is also connected in parallel between the live line and the neutral line, and the alarm branch includes the third intermediate normally open switch KA3-1 of the third intermediate relay connected in series and the alarm DL. In this patent, there are two third intermediate normally open switches KA3-1 of the third intermediate relay, which act synchronously.

This patent realizes the convenience of installation through the series induction and control structure, without manual intervention, automatic operation, real-time monitoring of power consumption, and automatic implementation of warning signals or alarms when the transformer is fully loaded or overloaded due to the user's electricity consumption. Prompt measures or compulsory measures such as power outages and work stoppages can effectively guarantee the safety of electricity use and production safety.

The series induction and control structure mainly includes contactors, current transformers, main current relays and other auxiliary circuits installed on the three-phase power line. Wherein, the three-phase power line is three power lines in the three-phase four-wire system power supply circuit, and also includes a neutral line. In this patent, the a-phase power line (commonly known as live line A) and the neutral line (ie N line) of the three-phase power line are selected as the auxiliary power supply of the auxiliary circuit.

In this patent, a contact normally open switch of a contactor is connected in series on the three-phase power line, and the coil of the contactor is connected in series between the live line and the neutral line of the above-mentioned auxiliary power supply through the fourth branch. Therefore, as long as the on-off of the fourth branch can be controlled, the power gain and loss of the contactor coil can be controlled, that is, the on-off of the three-phase power line can be controlled, and the power cut off for industrial full-load or overloaded power users can be realized. . In this patent, there are at least three current transformers, which are sequentially connected in series in the three-phase power lines. Therefore, the function of each current transformer is to monitor the current signal of its phase in real time, and convert the current signal into a corresponding smaller value current signal. The output end of each current transformer is correspondingly connected to a main current relay, therefore, the current transformer supplies power to the main current relay, and the main current relay collects the induced current signal of the three-phase power line from the current transformer, and uses it as its Judgment basis for the output action. The three main current relays all have a main normally open output switch, and the main normally open output switch has two output terminals, which are called the first terminal and the second terminal respectively for the convenience of description. In this patent, the first ends of the three main normally open output switches are shorted together, and the second ends of the three main normally open output switches are all shorted together. Therefore, the three main normally open output switches are connected in parallel and form a "parallel switch group".

In this patent, the first end of the parallel switch group is electrically connected to the live wire, and the second end of the parallel switch group is electrically connected to the neutral line through the third branch, and the third branch includes the fifth time relay connected in series , The fifth delay normally closed switch of the fifth time relay, and the contact auxiliary switch of the contactor. Therefore, when the user is running at full load or overload, as long as the current of one phase exceeds the standard, the parallel switch group will be closed, the power supply circuit of the fifth time relay will be connected, and the fifth time relay will act.

In this patent, a fifth branch is connected in parallel between the live line and the neutral line, and the fifth branch includes the third intermediate relay and the fifth delay normally open switch of the fifth time relay connected in series. When the fifth time relay acts, the power supply circuit of the third intermediate relay is connected, and the third intermediate relay acts.

An alarm branch is also connected in parallel between the live wire and the neutral line, and the alarm branch includes a third intermediate normally open switch and an alarm connected in series with the third intermediate relay. Therefore, after the action of the third intermediate relay, the power supply circuit of the alarm is connected, and the alarm starts to alarm.

After the delay time arrives, the relay action resumes at the fifth time.

In this patent, the delay time can be set for the fifth time relay. This delay time is the alarm time given by this patent to industrial users, that is to say, the longer this delay time is, the longer the time for this patent to alarm the user, which plays a better role in reminding and warning. The fifth delay normally closed switch of the fifth time relay is connected in series in the third branch, therefore, after the above-mentioned delay time arrives, that is, after the alarm duration arrives, the fifth delay normally closed switch will be disconnected, and the fifth delay normally closed switch will be disconnected. The time relay loses power, causing the third intermediate relay to lose power, the third intermediate normally open switch returns to the normally open state, the alarm power supply circuit is cut off, and the alarm ends.

In this patent, the third intermediate normally open switch of the third intermediate relay is connected in parallel between the first terminal and the second terminal of the main normally open output switch. The main function of this setting is to implement self-locking on the fifth time relay and the third intermediate relay within the alarm period, so as to ensure that the alarm will not automatically stop the alarm due to the recovery of the phase current within the alarm period, and strengthen the influence of the alarm role.

If the user fails to take effective measures to reduce the power consumption load after hearing the alarm signal, which affects the safety of power consumption and production safety, then this patent also has the function of forced power failure. In this patent, the first end of the parallel switch group is electrically connected to the live wire of the aforementioned auxiliary power supply, and the second end of the parallel switch group is electrically connected to the neutral wire through the coil of the first time relay. This constitutes a complete control loop, referred to as the first loop. Obviously, as long as one phase of the three-phase power line is fully loaded or overloaded, the corresponding main normally open output switch will be closed, and the relay coil will be energized at the first time. action. The delay time is to allow recovery time for the full load or overload operation reset of the factory electricity, that is to say, if the large current phenomenon is caused by accidental factors such as unstable operation of the equipment, within the set delay time, the current It will return to normal soon, and the relay will not act at the first time; if the equipment is indeed running at full load or overload, it is impossible to restore normal operation in a short period of time, that is, within the delay time mentioned above, and the relay will not operate at the first time. The control action will be output.

In this patent, the first delay normally open switch of the first time relay is connected in parallel between the live line and the neutral line through the first branch, and the first intermediate relay is also connected in series on the first branch. Therefore, when the first time relay operates, the first time delay normally open switch will be closed, the power supply circuit of the first intermediate relay will be connected, and the first intermediate relay will act. In this patent, it also includes a second branch connected in parallel between the live line and the neutral line, and the second time relay and the first intermediate normally open switch of the first intermediate relay are connected in series on the second branch. When the first intermediate relay acts, the first intermediate normally open switch is closed, therefore, the power supply circuit of the second time relay is connected, and the second time relay will act. In this patent, a first short circuit is electrically connected between the connection point of the first delay normally open switch and the first intermediate relay and the connection point of the first intermediate normally open switch and the second time relay, and the first short circuit is The self-locking of the first intermediate relay provides the condition. As mentioned above, when the first intermediate normally open switch is closed, the power supply circuit of the first intermediate relay also forms a self-locking function. One of the self-locking functions of the first intermediate relay is that after the first intermediate relay operates, even if the three-phase When the current of the power line returns to normal, the action output of the first intermediate relay will not be affected, and the first intermediate relay will still perform the output action.

As mentioned above, as long as the fourth branch is controlled, the cut-off of the industrial user's power supply can be controlled. Because the first intermediate normally-closed switch of the first intermediate relay is connected in series in the fourth branch, the action output of the first intermediate relay can realize the disconnection of the first intermediate normally-closed switch, that is, realize the power supply of industrial users. resection. This is the second self-locking function of the first intermediate relay, which is to control the removal of the power supply of industrial users.

In this patent, the second delay normally closed switch of the second time relay is connected in series on the first branch between the first intermediate relay and the neutral line. The delay time is the maintenance time for industrial users to cut off the power supply, that is, the power failure time, which can be set. When the specified power failure time expires, the second time relay will act and output, and its second time delay normally closed switch will be disconnected. As a result, the self-locking of the first intermediate relay is cut off, the first intermediate relay loses power, and the first intermediate normally closed switch is closed. As a result, the power supply circuit of the contactor is connected, the contactor starts to output, the three-phase power line is connected, and the industrial users resume power supply.

In this patent, this patent also includes a timing branch connected in parallel between the live wire and the neutral wire, and a fixed clock DSZ is connected in series on the timing branch. This patent also includes the auxiliary current relays KC4, KC5, KC6 connected in sequence at the output end of the current transformer, the first ends of the auxiliary normally open output switches KC4-1, KC5-1, KC6-1 of the three auxiliary current relays are all connected to the live wire Electrically connected, the second end of the auxiliary normally open output switch is electrically connected to the neutral line through a series branch composed of the third time relay KT3 and the timing normally open switch DSZ-1 of the fixed clock. The third delay normally open switch KT3-1 of the third time relay is connected in parallel between the live wire and the neutral wire through the sixth branch, and the second intermediate relay KA2 is connected in series on the sixth branch. This patent also includes a seventh branch connected in parallel between the live line and the neutral line, the fourth time relay KT4 and the second intermediate normally open switch KA2-1 of the second intermediate relay KA2 are connected in series on the seventh branch. The connection point of the third delay normally open switch and the second intermediate relay and the connection point of the second intermediate normally open switch and the fourth time relay are electrically connected with a second short line DJX2, between the second intermediate relay and the neutral line The fourth time-delay normally closed switch KT4-2 of the fourth time relay KT4 is connected in series on the sixth branch.

This patent also includes a timing branch with a timing function, which is also connected in parallel between the live wire and the neutral wire, and a timing clock is connected in series on the timing branch. The main function of the fixed clock is to limit the time period for power supply to enterprises, so that enterprises can carry out orderly power consumption and orderly production according to the overall power consumption planning and peak and valley periods of power consumption. The setting of the fixed clock can be set according to the power supply situation on the spot, such as setting by month or setting as night power consumption and so on. The main function of this setting is to reasonably allocate power consumption, improve power consumption efficiency and ensure power supply. This patent also includes auxiliary current relays connected in sequence to the output terminals of the three current transformers, the first ends of the auxiliary normally open output switches of the three auxiliary current relays are shorted together, and the second ends of the auxiliary normally open output switches are also shorted Together, therefore, the three auxiliary normally open output switches are connected in parallel, and constitute a "parallel switch group" similar to the aforementioned "parallel switch group". The first end of the parallel switch group is electrically connected to the fire wire, and the second end of the parallel switch group is electrically connected to the neutral line through a series branch, and the series branch includes a third time relay and a fixed clock connected in series. Regularly open the switch. Because the timing clock is directly connected in parallel between the live wire and the neutral wire, as long as the contactor is in the closed state, the power supply circuit of the timing clock must be connected, and the timing normally open switch must also be closed. Therefore, the power supply of the third time relay The circuit must be connected. After the delay time of the third time relay reaches, the third time relay will act.

The delay time is to allow recovery time for the full load or overload operation reset of the factory electricity, that is to say, if the large current phenomenon is caused by accidental factors such as unstable operation of the equipment, within the set delay time, the current It will return to normal soon, and the third time relay will not act; if the equipment is indeed running at full load or overload, it is impossible to restore normal operation in a short time, that is, within the above delay time, then the third time relay The control action will be output.

In this patent, the third delay normally open switch of the third time relay is connected in parallel between the live wire and the neutral wire through the sixth branch, and the second intermediate relay is also connected in series on the sixth branch. Therefore, when the third time relay acts, the third time delay normally open switch will be closed, the power supply circuit of the second intermediate relay will be connected, and the second intermediate relay will act. In this patent, it also includes a seventh branch connected in parallel between the live line and the neutral line, and the fourth time relay and the second intermediate normally open switch of the second intermediate relay are connected in series on the seventh branch. When the second intermediate relay acts, the second intermediate normally open switch is closed, therefore, the power supply circuit of the fourth time relay is connected, and the fourth time relay will act. In this patent, there is a second short wire electrically connected between the connection point of the third delay normally open switch and the second intermediate relay and the connection point of the second intermediate normally open switch and the fourth time relay, and the second short wire is The self-locking of the second intermediate relay provides the conditions. As mentioned above, when the third intermediate normally open switch is closed, the power supply circuit of the second intermediate relay also constitutes a self-locking. One of the self-locking functions of the second intermediate relay is that after the second intermediate relay operates, even if the current of the three-phase power line returns to normal, the operation output of the second intermediate relay will not be affected, and the second intermediate relay will still perform the output action.

As mentioned above, as long as the fourth branch is controlled, the cut-off of the industrial user's power supply can be controlled. Because the second intermediate normally-closed switch of the second intermediate relay is connected in series in the fourth branch, the action output of the second intermediate relay can realize the disconnection of the second intermediate normally-closed switch, that is, realize the power supply of industrial users. resection. This is the second self-locking function of the second intermediate relay, that is, to control and cut off the power supply of industrial users.

In this patent, the fourth delay normally closed switch of the fourth time relay is connected in series on the sixth branch between the second intermediate relay and the neutral line. The delay time is the maintenance time for industrial users to cut off the power supply, that is, the power failure time, which can be set. When the prescribed power failure time expires, the fourth time relay will act and output, and its fourth time delay normally closed switch will be disconnected. As a result, the self-locking of the second intermediate relay is cut off, the second intermediate relay loses power, and the second intermediate normally closed switch is closed. As a result, the power supply circuit of the contactor is connected, the contactor starts to output, the three-phase power line is connected, and the industrial users resume power supply.

In this patent, the arrears normally closed switch WHQF for the control output of the watt-hour meter is connected in series in the fourth branch. When the user is in arrears of electricity bills, the control signal of the watt-hour meter can directly cut off the power supply circuit of the contactor, resulting in a power outage of the three-phase power line, that is, the function of forced power outage in arrears is realized.

In this embodiment, a normally closed release button SB is connected in series on the third branch. In this way, if the industrial user knows the full load or overload situation and is dealing with it, he can press the release button, so that the alarm will no longer alarm, which avoids interference and is very user-friendly.

Claims (4)

1. A capacity safety controller for a power system, characterized in that it includes current transformers (BHa, BHb, BHc) sequentially connected to the three-phase power lines (a, b, c), and the output terminals of the current transformers Corresponding electrical connections are the main current relays (KC1, KC2, KC3), the first end of the main normally open output switches (KC1-1, KC2-1, KC3-1) of the three main current relays (KC1, KC2, KC3) Both are electrically connected to the live wire (A), and the second end of the main normally open output switch (KC1-1, KC2-1, KC3-1) is electrically connected to the neutral wire (N) through the coil of the first time relay (KT1); The first delay normally open switch (KT1-1) of the first time relay (KT1) is connected in parallel between the live wire (A) and the neutral wire (N) through the first branch, and the first branch is connected in series with the first Intermediate relay (KA1); also includes a second branch connected in parallel between the live wire (A) and the neutral wire (N), and the second time relay (KT2) and the first intermediate relay (KA1) are connected in series on the second branch The first intermediate normally open switch (KA1-1); the connection point of the first delay normally open switch (KT1-1) and the first intermediate relay (KA1) and the first intermediate normally open switch (KA1-1) and the second The connection point of the second time relay (KT2) is electrically connected with the first short wire (DJX1), and the first branch between the first intermediate relay (KA1) and the neutral line (N) is connected in series with the second time relay ( The second delay normally closed switch (KT2-2) of KT2); the second end of the main normally open output switch (KC1-1, KC2-1, KC3-1) also passes through the third branch and the neutral line (N) Electrical connection, the third branch includes the fifth time relay (KT5) connected in series, the fifth delay normally closed switch (KT5-2) of the fifth time relay (KT5), the three-phase power line (a, b, c) The contactors (KM) are connected in series with contact normally open switches (KM-1, KM-2, KM-3), and the contactors (KM) are connected in series to the live wire (A) through the fourth branch and the neutral line (N), the fourth branch includes the first intermediate normally closed switch (KA1-2) of the first intermediate relay (KA1) connected in series and the second intermediate normally closed switch of the second intermediate relay (KA2) switch (KA2-2), the contact auxiliary switch (KM-0) of the contactor (KM) is also connected in series in the third branch; a fifth Branch, the fifth branch includes the fifth delay normally open switch (KT5-1) of the third intermediate relay (KA3) and the fifth time relay (KT5) connected in series; the third intermediate relay (KA3) The third intermediate normally open switch (KA3-1) is connected in parallel between the first end and the second end of the main normally open output switch (KC1-1, KC2-1, KC3-1); live wire (A) and neutral wire ( There is also an alarm branch connected in parallel between N), and the alarm branch includes the third intermediate normally open switch (KA3-1) of the third intermediate relay (KA3) connected in series and the alarm (DL ). 2. A capacity safety controller for power system according to claim 1, characterized in that: it also includes a timing branch connected in parallel between the live line (A) and the neutral line (N), and the timing branch is connected in series with Fixed clock (DSZ); also includes secondary current relays (KC4, KC5, KC6) successively connected to the output terminals of current transformers (BHa, BHb, BHc), and three secondary current relays (KC4, KC5, KC6). The first ends of the output switches (KC4-1, KC5-1, KC6-1) are electrically connected to the live wire (A), and the second ends of the auxiliary normally open output switches (KC4-1, KC5-1, KC6-1) The series branch composed of the third time relay (KT3) and the timing normally open switch (DSZ-1) of the fixed clock (DSZ) is electrically connected to the neutral line (N); the third delay of the third time relay (KT3) The normally open switch (KT3-1) is connected in parallel between the fire wire (A) and the neutral wire (N) through the sixth branch, and the second intermediate relay (KA2) is connected in series on the sixth branch; ) and the seventh branch between the neutral line (N), the fourth time relay (KT4) and the second intermediate normally open switch (KA2-1) of the second intermediate relay (KA2) are connected in series on the seventh branch; Electrical connection between the connection point of the third delay normally open switch (KT3-1) and the second intermediate relay (KA2) and the connection point of the second intermediate normally open switch (KA2-1) and the fourth time relay (KT4) There is a second short circuit (DJX2), a fourth delay normally closed switch (KT4- 2). 3. A capacity safety controller for power system according to claim 1, characterized in that: the fourth branch is also connected in series with an arrears normally closed switch (WHQF) for controlling the output of the watt-hour meter. 4. A capacity safety controller for power system according to claim 3, characterized in that: a normally closed release button (SB) is connected in series on the third branch.