CN219717874U - Protection circuit and protection system for power consumption loop - Google Patents

Abstract

The utility model relates to a protection circuit and a protection system of an electric loop. The protection circuit comprises a first switch circuit, a second switch circuit, a control unit and an information acquisition unit; the on-off response speed of the second switch circuit is faster than that of the first switch circuit; the first end of the first switch circuit is connected with the control unit, the second end of the first switch circuit is connected with a power supply in the power utilization loop, and the third end of the first switch circuit is connected with a load in the power utilization loop; the control unit is connected with the information acquisition unit; the first end of the second switch circuit is connected with the control unit, the second end of the second switch circuit is connected between the third end of the first switch circuit and the load in the power utilization loop, and the third end of the second switch circuit is respectively connected with the power supply in the power utilization loop and the load in the power utilization loop, or the third end of the second switch circuit is grounded. When the power utilization circuit fails, the first switch circuit and the second switch circuit are correspondingly controlled, so that the speed of cutting off the power utilization circuit is increased, and the load or a human body is timely protected.

Description

Protection circuit and protection system for power consumption loop

Technical Field

The utility model relates to the technical field, in particular to a protection circuit and a protection system of an electric loop.

Background

With the development of the technical field of electricity management, the safe operation of an electricity utilization loop becomes a key research problem. In a typical power circuit, a circuit breaker (i.e., a switching circuit) is connected in series with a load (e.g., a lamp), and the circuit can be controlled in the power circuit by the circuit breaker to turn on and off the circuit. However, during the use process, if electricity consumption fails (for example, the failure includes electric leakage, short circuit, surge impact, etc.), damage is caused to the load in the electricity consumption loop. Especially, when the electricity leakage occurs in the electricity utilization circuit, the electric shock event of the human body is easy to occur. Therefore, in order to protect liabilities on the power circuit and to avoid human electric shock accidents, it is common practice to install a circuit breaker on the power circuit, so that when the power circuit fails, the conduction on the load side is timely disconnected through the circuit breaker. However, by only installing a circuit breaker on the power circuit, the load or the human body cannot be protected in time when the power circuit fails.

Disclosure of Invention

Accordingly, it is necessary to provide a protection circuit and a protection system for an electric circuit, which are capable of solving the problem that a load or a human body cannot be protected in time when the electric circuit fails.

In order to achieve the above objective, in one aspect, an embodiment of the present utility model provides a protection circuit for an electric circuit, including a first switch circuit, a second switch circuit, a control unit, and an information acquisition unit; the on-off response speed of the second switch circuit is faster than that of the first switch circuit;

the first end of the first switch circuit is connected with the control unit, the second end of the first switch circuit is connected with a power supply in the power utilization loop, and the third end of the first switch circuit is connected with a load in the power utilization loop; the control unit is connected with the information acquisition unit;

the first end of the second switch circuit is connected with the control unit, the second end of the second switch circuit is connected between the third end of the first switch circuit and the load in the power utilization loop, and the third end of the second switch circuit is respectively connected with the power supply in the power utilization loop and the load in the power utilization loop, or the third end of the second switch circuit is grounded.

In one embodiment, the second switching circuit includes a first MOS transistor and a second MOS transistor;

the grid electrode of the first MOS tube and the grid electrode of the second MOS tube are connected with the control unit; the drain electrode of the first MOS tube is connected with the third end of the first switch circuit, and the source electrode of the first MOS tube is connected with the source electrode of the second MOS tube; the drain electrode of the second MOS tube is respectively connected with a power supply in the power utilization loop and a load in the power utilization loop, or the drain electrode of the second MOS tube is grounded.

In one embodiment, the information acquisition unit includes a leakage current detection unit;

the first end of the leakage current detection unit is connected with the control unit, the second end of the leakage current detection unit is connected between the second end of the second switch circuit and the load in the power utilization loop, and the third end of the leakage current detection unit is connected between the third end of the second switch circuit and the load in the power utilization loop.

In one embodiment, the information acquisition unit further comprises a short circuit detection unit;

the first end of the short circuit detection unit is connected with the control unit, the second end of the short circuit detection unit is connected with the second end of the second switch circuit, and the third end of the short circuit detection unit is connected with the second end of the leakage current detection unit.

In one embodiment, the information acquisition unit further comprises a surge detection unit;

the first end of the surge detection unit is connected with the control unit, the second end of the surge detection unit is connected with the second end of the first switch circuit, and the third end of the surge detection unit is connected with the third end of the second switch circuit.

In one embodiment, the protection circuit of the power consumption loop further comprises a reactance protection unit;

the reactance protection unit has a first end connected between the second end of the first switching circuit and the power supply in the power consumption loop and a second end connected between the third end of the second switching circuit and the power supply in the power consumption loop.

In one embodiment, the reactance protection unit includes a reactance unit, a first resistor, a second resistor, and a capacitance unit;

the first end of the reactance unit is respectively connected with a power supply in the power utilization loop and the first end of the first resistor, and the second end of the reactance unit is respectively connected with the second end of the first switch circuit and the first end of the second resistor;

the first end of the capacitor unit is connected with the second end of the first resistor, the second end of the capacitor unit is connected with the second end of the second resistor, and the third end of the capacitor unit is connected between the third end of the second switch circuit and a power supply in the power utilization loop.

In one embodiment, the number of second switching circuits is at least two, wherein a third end of at least one second switching circuit is grounded.

In one embodiment, the first switching circuit is a mechanical circuit breaker or a permanent magnet circuit breaker.

On the other hand, the embodiment of the utility model provides a protection system of an electricity utilization loop, which comprises a service unit and the protection circuit of the electricity utilization loop; the service unit is connected with the control unit in the protection circuit in a wireless way.

One of the above technical solutions has the following advantages and beneficial effects:

the protection circuit of the power utilization circuit provided by the embodiments of the utility model comprises a first switch circuit, a second switch circuit, a control unit and an information acquisition unit. The first end of the first switch circuit is connected with the control unit, the second end of the first switch circuit is connected with a power supply in the power utilization loop, and the third end of the first switch circuit is connected with a load in the power utilization loop. The control unit is connected with the information acquisition unit. The first end of the second switch circuit is connected with the control unit, the second end of the second switch circuit is connected between the third end of the first switch circuit and the load in the power utilization loop, and the third end of the second switch circuit is respectively connected with the power supply in the power utilization loop and the load in the power utilization loop, or the third end of the second switch circuit is grounded. The first switch circuit is arranged in the main circuit of the power utilization circuit, the second switch circuit is arranged in the bypass of the power utilization circuit, the on-off response speed of the second switch circuit is faster than that of the first switch circuit, and when the power utilization circuit breaks down, the first switch circuit and the second switch circuit are correspondingly controlled, so that the speed of cutting off the power utilization circuit is improved, and the load or a human body is timely protected.

Drawings

Fig. 1 is a schematic structural diagram of an electric circuit according to an embodiment of the present utility model.

Fig. 2 is a schematic structural diagram of a second switching circuit according to an embodiment of the present utility model.

Fig. 3 is a schematic structural diagram of an information acquisition unit according to an embodiment of the present utility model.

Fig. 4 is a schematic diagram of another structure of an electric circuit according to the present utility model.

Fig. 5 is a schematic structural diagram of a reactance protection unit according to the embodiment of the present utility model.

Fig. 6 is a schematic structural diagram of a protection system according to an embodiment of the present utility model.

Detailed Description

In order that the utility model may be readily understood, a more complete description of the utility model will be rendered by reference to the appended drawings. Preferred embodiments of the present utility model are shown in the drawings. This utility model may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to and integrated with the other element or intervening elements may also be present. The terms "mounted," "one end," "the other end," and the like are used herein for illustrative purposes only.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

In order to solve the problems that the circuit breaker in the prior art has relatively long disconnection control time, and cannot realize high-speed disconnection, so that the load 19 or a human body cannot be protected in time when a power circuit breaks down. As shown in fig. 1, a protection circuit of an electric loop is provided, which includes a first switch circuit 11, a second switch circuit 13, a control unit 15, and an information acquisition unit 17. The first switch circuit 11 is connected to the main circuit of the power circuit, and is used for controlling the on and off of the main circuit of the power circuit. In one example, the first switch circuit 11 is a mechanical circuit breaker or a permanent magnet circuit breaker, and the specific type of the first switch circuit 11 may be selected according to actual requirements, which is not limited herein. The second switch circuit 13 is provided at a bypass of the power consumption circuit for controlling on and off of the bypass of the power consumption circuit. Note that, the on-off response time period of the second switch circuit 13 is shorter than the on-off response time period of the first switch circuit 11, so that when the control command is simultaneously sent to the first switch circuit 11 and the second switch circuit 13, the second switch circuit 13 formulates the control command faster than the first switch circuit 11. The on-off response time length refers to the time length required by the switch circuit to respond to the control instruction after receiving the control instruction.

For this purpose, the on-off response time of the second switching circuit 13 is shorter than the on-off response time of the first switching circuit 11, and in one example, as shown in fig. 2, the second switching circuit 13 includes a first MOS transistor and a second MOS transistor; the grid electrode of the first MOS tube and the grid electrode of the second MOS tube are connected with the control unit 15; the drain electrode of the first MOS tube is connected with the third end of the first switch circuit 11, and the source electrode of the first MOS tube is connected with the source electrode of the second MOS tube; the drain electrode of the second MOS tube is respectively connected with a power supply 21 in the power utilization loop and a load 19 in the power utilization loop, or is used for grounding. In one example, the MOS transistor may be an N-type MOS transistor or a P-type MOS transistor.

The specific connection relation of the protection circuit of the power utilization loop is as follows: the first switch circuit 11 has a first end connected to the control unit 15, a second end for connecting to a power source 21 in the power loop, and a third end for connecting to a load 19 in the power loop. When the power source 21 is a domestic power supply line, the second end of the first switch circuit 11 may be connected to a live wire of the domestic power supply line. In one example, load 19 may be a light bulb, a television, a computer, a washing machine, or the like.

The first end of the second switch circuit 13 is connected to the control unit 15, the second end is connected between the third end of the first switch circuit 11 and the load 19 in the power consumption loop, the third end is used for respectively connecting the power supply 21 in the power consumption loop and the load 19 in the power consumption loop, or the third end of the second switch circuit 13 is used for grounding. When the power source 21 is a domestic power supply line, the third terminal of the second switch circuit 13 may be connected to a neutral line of the domestic power supply line.

The control unit 15 is connected to the first switch circuit 11, the second switch circuit 13, and the information acquisition unit 17, respectively. In one example, the control unit 15 may be a single chip microcomputer, a programmable logic control unit 15, or a system on a chip.

In the normal power utilization state, the first switch circuit 11 is in an on state, and the second switch circuit 13 is in an off state. At this time, the current starts from the power source 21, flows through the first switch circuit 11, through the load 19, and then flows back to the power source 21, or the current starts from the power source 21, flows through the load 19, through the first switch circuit 11, and then flows back to the power source 21, thereby forming the main loop of the power utilization loop. The second switching circuit 13 constitutes a bypass of the power circuit, and in a normal power consumption state, the second switching circuit 13 is in an off state, and no current flows through the second switching circuit 13.

The information acquisition unit 17 acquires the electrical parameters of the power circuit and transmits the electrical parameters to the control unit 15. It should be noted that the electrical parameter collected by the information collecting unit 17 may be one or any combination of a current value, a voltage value, and an electromagnetic intensity. For example, when the electrical parameter is a current value, and when the current value is greater than the safe current threshold, it indicates that the power circuit is malfunctioning. And when the electric parameter is a voltage value and the voltage value is larger than a safety voltage threshold value, the fault of the circuit is indicated.

In one example, as shown in fig. 3, the information collection unit 17 includes a leakage current detection unit 171. The leakage current detection unit 171 has a first end connected to the control unit 15, a second end connected between the second end of the second switch circuit 13 and the load 19 in the power consumption loop, and a third end connected between the third end of the second switch circuit 13 and the load 19 in the power consumption loop. The leakage current detection unit 171 is, but not limited to, a hall sensor unit, a fluxgate sensor unit. The leakage current detecting unit 171 detects the residual current on the load 19 side, and if the residual current is greater than the first preset safe current threshold, it indicates that the power circuit fails.

It should be noted that the first preset safe current threshold value may be specifically set according to the actual leakage protection type of the product, where the leakage protection type product includes AC type, a type, B type, etc. products, and different first preset safe current threshold values may be designed for different leakage protection types. The AC type leakage protection product is mainly applied to a general alternating current circuit, the A type leakage protection product is mainly applied to an alternating current distribution line and a pulsating direct current distribution line, and the B type leakage protection product is mainly applied to the alternating current distribution line, the pulsating direct current distribution line and electric equipment for generating smooth direct current.

In some embodiments, for example, an AC-type leakage protection product is taken as an example, the first preset safety current threshold is set to 30mA according to CCC standard in china, that is, when the residual current is greater than 30mA, the fault of the power circuit is indicated; the first preset safe current threshold value is set to 10mA according to the CE standard requirement in Europe, and the first preset safe current threshold value is set to 6mA according to the UL standard requirement in Europe.

Similarly, the requirements of the leakage protection products of type a and type B on the setting of the first preset safe current threshold are not described in detail herein.

In one example, as shown in fig. 3, the information acquisition unit 17 further includes a short circuit detection unit 173. The short circuit detection unit 173 has a first end connected to the control unit 15, a second end connected to the second end of the second switch circuit 13, and a third end connected to the second end of the leakage current detection unit 171. In one example, the short circuit detection unit 173 is, but is not limited to: and a current transformer unit. In another example, the short circuit detection unit 173 includes a shunt resistor connected between the second terminal of the second switching circuit 13 and the load 19. The short circuit detection unit 173 detects the branch current passing through the input load 19 side, and if the branch current is greater than the second preset safe current threshold, it indicates that the power consumption circuit has a fault.

In particular, the second preset safe current threshold is specifically set according to the actual rated operating current, for example, in some embodiments, the second preset safe current threshold is set according to twice the rated operating current. More specifically, common rated operating currents include, but are not limited to, current values of 10A, 16A, 32A, 63A, 125A, etc., for example, when the rated operating current is set to 10A, the second preset safety current threshold is set to 20A, and when the branch current is greater than 20A, a short circuit fault occurs in the circuit loop. Similarly, when the rated operating current is other, the same is repeated, and a detailed description is not repeated here.

Of course, in other embodiments, the second preset safety current threshold is not limited to be set according to twice the rated working current according to the actual protection requirement, and may be other values greater than the rated working current, which are not described in detail herein.

In one example, as shown in fig. 3, the information acquisition unit 17 further includes a surge detection unit 175. The surge detection unit 175 has a first end connected to the control unit 15, a second end connected to the second end of the first switch circuit 11, and a third end connected to the third end of the second switch circuit 13. It should be noted that, the surge detection unit 175 is configured to detect an electromagnetic intensity in an electrical environment where the electrical circuit is located, for example, when lightning strikes around the electrical circuit, an electromagnetic field with an extremely high intensity is generated, so that a surge current or a surge voltage is generated due to a sudden increase of a current or a voltage of the electrical circuit, where the surge detection unit 175 is capable of detecting the surge current or the surge voltage of the electrical circuit in the current environment, if a current value of the electrical circuit is greater than a preset surge current threshold value, it indicates that a surge current exists, and if a voltage value of the electrical circuit is greater than a preset surge voltage threshold value, it indicates that a surge voltage exists, and when the surge current or the surge voltage exists, it is easy to cause damage of a load 19 on a load side in the electrical circuit.

Specifically, in some embodiments, at least one of a varistor, a TVS tube, and a gas discharge tube may be utilized as the voltage detection device of the surge detection unit 175. The surge voltage threshold is not limited, and the surge voltage threshold may be set to be greater than the rated voltage threshold, for example, in some embodiments, the surge voltage threshold may be set to be greater than or equal to twice the rated voltage threshold, if the rated voltage threshold is 220V, the surge voltage threshold is greater than or equal to 440V (e.g. 470V), and if the voltage value of the power circuit is greater than 470V, the surge voltage is indicated.

It should be noted that the rated voltage threshold may be specifically set according to the actual electricity consumption situation, and the same is true for the surge voltage threshold.

Specifically, in some embodiments, at least one of a transformer, a shunt resistor, a TMR sensor, a hall sensor may be utilized as the current detection device of the surge detection unit 175. The inrush current threshold is not limited, for example, in some embodiments, the inrush current threshold may be set to 100 times the rated current threshold, for example, if the rated current threshold is 10A, the inrush current threshold is set to 1000A, and when the current value of the power circuit is greater than 1000A, the existence of an inrush current is indicated.

It should be noted that the rated current threshold value can be specifically set according to the actual electricity consumption situation, and the same is true for the surge current threshold value. When the control unit 15 determines that the electrical circuit has a fault (for example, the fault is a short circuit, a leakage current, lightning, etc.) according to the electrical parameter, the control unit 15 may individually control the first switch circuit 11 to be turned off, and cut off the main circuit of the electrical circuit, thereby cutting off the current of the load 19. The second switching circuit 13 may be controlled separately to conduct and bypass the conductive circuit so that current flows from the power supply 21, through the first switching circuit 11, through the second switching circuit 13, back to the power supply 21, or from the power supply 21, through the second switching circuit 13, through the first switching circuit 11, back to the power supply 21, or when the second switching circuit 13 is grounded, current flows from the power supply 21, through the second switching circuit 13, to the bottom, thereby cutting off the current of the load 19. The first switching circuit 11 may be controlled to be turned off and the second switching circuit 13 may be controlled to be turned on at the same time to cut off the bypass of the main circuit and the conduction circuit of the power consumption circuit.

Some faults in the power circuit may be transient faults, which may be recovered instantaneously, without disconnecting the main circuit of the power circuit. If the main circuit of the power consumption circuit is repeatedly disconnected for such a failure, the first switch circuit 11 and the second switch circuit 13 are burdened on the one hand, and the load 19 is inconveniently consumed. To solve this problem, in one example, the control unit 15 starts timing when the electrical circuit is judged to be faulty according to the electrical parameter, and when the first timing time is longer than or equal to a first preset time period, the control unit 15 controls the first switch circuit 11 to be turned off and/or controls the second switch circuit 13 to be turned on according to the electrical parameter when the electrical circuit is still in the faulty state; when the first timing duration is greater than or equal to the first preset duration, the control unit 15 determines that the power circuit is restored to be normal according to the electrical parameter, and maintains the first switch circuit 11 in the on state and maintains the second switch circuit 13 in the off state.

The control unit 15 uses the timing unit therein to perform timing, the control unit 15 acquires the electrical parameters of the first switch circuit 11 and the second switch circuit 13 in real time through the information acquisition unit 17, and when a fault is determined according to the electrical parameters at the current time, the control unit 15 controls the timing unit to start timing from the current time. In one example, the first preset time period is set according to a longest time period that can be loaded 19 or the human body resists the failure of the power consumption circuit, and the first preset time period is smaller than the longest time period. In one example, the first preset time period may be set according to an on-off response time period of the first switch circuit 11, and the first preset time period is smaller than the on-off response time period of the first switch circuit 11. In one example, the first preset time period may be set according to an on-off response time period of the second switch circuit 13, and the first preset time period is smaller than the on-off response time period of the second switch circuit 13.

If the fault of the power consumption circuit is continuously equal to or exceeds the first preset time period, the control unit 15 may only control the first switch circuit 11 to be turned off, directly cut off the main circuit of the power consumption circuit, the control unit 15 may also only control the second switch circuit 13 to be turned on, directly conduct the bypass of the power consumption circuit, and the control unit 15 may also simultaneously control the first switch circuit 11 to be turned off and the second switch circuit 13 to be turned on. However, if the failure of the power consumption circuit continues for not more than the first preset time period, the control unit 15 does not control the first switch circuit 11 and the second switch circuit 13, and the first switch circuit 11 maintains the on state and the second switch circuit 13 maintains the off state.

The first switch circuit 11 is located on the main circuit of the power-using circuit, so as to avoid the problem of power supply failure caused by the failure of the first switch circuit 11. In the embodiment controlling the second switch circuit 13 to be turned on, the first switch circuit 11 is controlled to mitigate damage to the first switch circuit 11 caused by frequent switching operations, and avoid accelerating the aging of the first switch circuit 11, by distinguishing between:

the control unit 15 starts timing when controlling the second switch circuit 13 to be turned on, and when the second timing time is longer than or equal to the second preset time, the control unit 15 determines that the power circuit is still in a fault state according to the electrical parameter, maintains the first switch circuit 11 in a turned-on state, and controls the second switch circuit 13 to be turned off. When the second timing duration is less than the second preset duration, the control unit 15 judges that the power consumption circuit is recovered to be normal according to the electrical parameter, and then controls the first switch circuit 11 to be disconnected.

When the fault duration of the power consumption circuit is equal to or exceeds the first preset duration, the control unit 15 controls the second switch circuit 13 to be conducted as a measure for temporarily avoiding damage to the load 19 or the human body, the control unit 15 controls the second switch circuit 13 to be conducted, controls the timing unit to start timing, counts the second timing duration, and acquires the electrical parameters of the first switch circuit 11 and the second switch circuit 13 in real time through the information acquisition unit 17 so as to judge whether the power consumption circuit is still in a fault state, and when the fault duration of the power consumption circuit is equal to or exceeds the second preset duration, the control unit 15 controls the first switch circuit 11 to be disconnected, cuts off the main circuit of the power consumption circuit so as to eliminate risks caused by the fault to the load 19 or the human body, and the second switch circuit 13 forms double insurance, so that the response speed of the power consumption cut-off 21 is improved, and the power consumption safety is increased. When the fault of the power utilization circuit does not continue to exceed the second preset time period, the control unit 15 does not control the first switch circuit 11, maintains the first switch circuit 11 to be turned on, and controls the second switch circuit 13 to be turned off. It should be noted that, in the process of the timing unit timing the second timing duration, the first timing duration is still timed. In one example, the second preset time period is set according to a longest time period that can be loaded 19 or that a human body resists the failure of the power consumption circuit, the second preset time period is smaller than the longest time period, and a sum of the first preset time period and the second preset time period is smaller than the longest time period. In one example, the second preset duration may be set according to an on-off response duration of the first switch circuit 11, the second preset duration is smaller than the on-off response duration of the first switch circuit 11, and a sum of the first preset duration and the second preset duration is smaller than the on-off response duration of the first switch circuit 11. In one example, the second preset duration may be set according to an on-off response duration of the second switch circuit 13, the second preset duration is smaller than the on-off response duration of the second switch circuit 13, and a sum of the first preset duration and the second preset duration is smaller than the on-off response duration of the second switch circuit 13.

The utility model can not only increase the protection of the first switch circuit 11 and the second switch circuit 13 and the flexibility of the circuit for cutting off through the above-mentioned time duration, but also increase the protection of the first switch circuit 11 and the second switch circuit 13 and the flexibility of the circuit for cutting off through the size of the fault. In some cases, although the fault of the power consumption circuit occurs, the fault is not large enough to affect the load 19 or the human body, or is in a range acceptable by the load 19 or the human body, at this time, the power consumption circuit is not required to be disconnected, so that frequent control of on-off of the first switch circuit 11 and on-off of the second switch circuit 13 is avoided, and the service lives of the first switch circuit 11 and the second switch circuit 13 are shortened. In one example, the control unit 15 sends a service maintenance signal to the outside (e.g., a worker computer, the service unit 61, etc.), alerting the worker to service maintenance.

In this case, in one example, the control unit 15 controls the first switch circuit 11 to be turned off when it is judged that the electrical parameter is smaller than the first preset value and larger than the second preset value. The control unit 15 controls the first switch circuit 11 to be turned off and the second switch circuit 13 to be turned on when determining that the electrical parameter is greater than or equal to the first preset value. It should be noted that the first preset value is greater than the second preset value. In one example, the first preset value is set according to a limit acceptable to the load 19 or a human body, and the second preset value is 30% to 60% of the first preset value, for example, 40% of the first preset value, and 50% of the first preset value. The first preset value and the second preset value correspond to the type of the electric parameter, when the electric parameter is a current value, the first preset value and the second preset value are also current values, and when the electric parameter is electromagnetic intensity, the first preset value and the second preset value are also electromagnetic intensity. When the electrical parameter is between the second preset value and the first preset value, it is indicated that the fault is not large, which can be dealt with by controlling the first switching circuit 11 to be turned off. When the electrical parameter exceeds the first preset value, the fault is larger, and the damage to the load 19 or the human body is caused, so that the control unit 15 controls the first switch circuit 11 to be disconnected, the main circuit of the power consumption circuit and the second switch circuit 13 to be switched on, and the bypass of the power consumption circuit is switched on, thereby realizing double insurance and accelerating the response speed of cutting off the power supply 21.

The present utility model can also increase the protection of the first switching circuit 11 and the second switching circuit 13 and increase the flexibility of the cut-off circuit by a combination of the above-described timing duration and the size of the fault.

In one example, the control unit 15 starts timing when determining that the electrical parameter is smaller than the first preset value and larger than the second preset value, and when the first timing is longer than or equal to the first preset time period, the control unit 15 determines that the electrical parameter is still smaller than the first preset value and larger than the second preset value, and then controls the first switch circuit 11 to be turned off. When the first timing duration is less than the first preset duration, the control unit 15 determines that the electrical parameter becomes less than the second preset value, and controls the first switch circuit 11 to be turned on.

The control unit 15 starts timing when the electrical parameter is determined to be greater than or equal to a first preset value, and when the electrical parameter is determined to be greater than or equal to the first preset time length during the first timing, the control unit 15 controls the first switch circuit 11 to be turned off and controls the second switch circuit 13 to be turned on when the electrical parameter is determined to be still greater than or equal to the first preset value. When the first timing duration is less than the first preset duration, the control unit 15 determines that the electrical parameter becomes less than the second preset value, and controls the first switch circuit 11 to be turned on and the second switch circuit 13 to be turned off.

In one example, the control unit 15 controls the second switch circuit 13 to be turned on and starts to count when the electrical parameter is determined to be greater than or equal to the first preset value, and controls the first switch circuit 11 to be turned off when the electrical parameter is determined to be still greater than or equal to the first preset value when the second count is greater than or equal to the second preset period. When the second timing duration is less than the second preset duration, the control unit 15 maintains the first switch circuit 11 in the on state and controls the second switch circuit 13 to be turned off when the electrical parameter is determined to be less than the second preset value.

To further improve the electrical safety performance, in one example, the number of second switch circuits 13 is at least two, wherein the third terminal of at least one second switch circuit 13 is used for grounding. For example, the number of the second switch circuits 13 is two, three or four, and the specific number can be determined according to practical needs, so as to enhance the safety function by arranging at least two second switch circuits 13 on the bypass, and avoid the risk that the power supply 21 cannot be cut off due to damage of the second switch circuits 13 when only one second switch circuit 13 is arranged.

The first control mode is as follows: the control unit 15 controls all the second switch circuits 13 to be turned on when controlling the second switch circuits 13 to be turned on. The second control mode is as follows: the control unit 15 controls one of the second switch circuits 13 to be turned on when controlling the second switch circuits 13 to be turned on, and alternately controls the second switch circuits 13 to be turned on in different control processes, in other words, controls one of the second switch circuits 13 to be turned on when the second switch circuits 13 need to be controlled to be turned on when each time the power circuit fails, and the same second switch circuit 13 is used discontinuously.

In order to ensure that the second switching circuit 13 functions during the switching off of the power supply 21, avoiding the risk of a slow response speed to the switching off of the power supply 21 due to a failure of the second switching circuit 13, the control unit 15 checks, in one example, whether the second switching circuit 13 is faulty or not, and if it is checked that the second switching circuit 13 is faulty, a warning signal is issued. The warning signal includes at least the number information, the position information, and the fault type corresponding to the faulty second switch circuit 13. The control unit 15 may issue a warning signal to the mobile terminal, the computer terminal, or the service unit 61 of the worker to remind the worker of maintenance. In one example, the control unit 15 sends a control instruction to the second switch circuit 13 when the power consumption circuit is not powered, and monitors whether the second switch circuit 13 responds to the control instruction to determine whether the second switch circuit 13 fails, and if not, the second switch circuit 13 fails.

In order to record the control situation of the control unit 15, the recorded data are used for analysis. In one example, the control unit 15 comprises a wireless module; the wireless module is used for wireless connection with the service unit 61; the control unit 15 transmits the monitoring information to the service unit 61 through the wireless module. The monitoring information includes at least failure time information, failure position information, failure type information, number information of the first switch circuit 11, number information of the second switch circuit 13, and control information. In one example, the control unit 15 transmits the monitoring information to the service unit 61 through the wireless module at a fixed period. In one example, the fixed period is 7 days, 15 days, or 30 days.

In order to avoid damage to the power circuit caused by excessive current in the moment, in one example, the protection circuit of the power circuit further comprises a reactance protection unit. As shown in fig. 4, the reactance protection unit has a first end connected between the second end of the first switching circuit 11 and the power supply 21 in the power consumption circuit, and a second end connected between the third end of the second switching circuit 13 and the power supply 21 in the power consumption circuit. When the instantaneous current is too large, the reactance protection unit is used for absorbing part of the current so as to reduce the impact of the excessive instantaneous current on the power utilization loop.

In one example, the reactance protection unit includes a reactance unit L, a first resistor R1, a second resistor R2, and a capacitance unit C. The first end of the reactance unit L is connected to the power supply 21 in the power consumption loop and the first end of the first resistor R1, respectively, and the second end is connected to the second end of the first switch circuit 11 and the first end of the second resistor R2, respectively. The first end of the capacitor unit C is connected to the second end of the first resistor R1, the second end is connected to the second end of the second resistor R2, and the third end is connected between the third end of the second switch circuit 13 and the power source 21 in the power consumption loop.

When the second switch circuit 13 is closed, the load 19 side is short-circuited, and the current of the power consumption loop rapidly flows to the second switch circuit 13, at this time, the reactance unit can absorb part of the current in the power consumption loop and release the absorbed current through the capacitance unit, so that the situation that the second switch circuit 13 is damaged due to overlarge current at the moment of closing and conducting is avoided, and the normal operation of the second switch circuit 13 can be effectively protected.

The protection circuit of the utility model comprises a first switch circuit 11, a second switch circuit 13, a control unit 15 and an information acquisition unit 17. The first switch circuit 11 has a first end connected to the control unit 15, a second end connected to the power source 21 in the power circuit, and a third end connected to the load 19 in the power circuit. The control unit 15 is connected to the information acquisition unit 17. The first end of the second switch circuit 13 is connected to the control unit 15, the second end is connected between the third end of the first switch circuit 11 and the load 19 in the power consumption loop, and the third end is respectively connected to the power supply 21 in the power consumption loop and the load 19 in the power consumption loop, or the third end of the second switch circuit 13 is grounded. By installing the first switch circuit 11 in the main circuit of the power consumption circuit, installing the second switch circuit 13 in the bypass of the power consumption circuit, and the on-off response speed of the second switch circuit 13 is faster than that of the first switch circuit 11, when the power consumption circuit breaks down, the first switch circuit 11 and the second switch circuit 13 are correspondingly controlled, so that the speed of cutting off the power consumption circuit is improved, and the load 19 or a human body is timely protected.

In one embodiment, there is also provided a protection system for an electric circuit, including a service unit 61 and a protection circuit for the electric circuit; the service unit 61 is connected wirelessly to the control unit 15 in the protection circuit.

It should be noted that, the protection circuit of the power consumption circuit in this embodiment is the same as that in each embodiment of the protection circuit of the power consumption circuit of the present utility model, and specific cases refer to each embodiment of the protection circuit of the power consumption circuit of the present utility model, and will not be described herein.

The control unit 15 is connected with the service unit 61 in a wireless manner, and the control unit 15 transmits all information generated in the control process to the service unit 61 for storage, so that a worker can study and analyze the stored information. In one example, the information includes failure time information, failure location information, failure type information, number information of the first switch circuit 11, number information of the second switch circuit 13, and control information.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the utility model, which are described in detail and are not to be construed as limiting the scope of the claims. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims (10)

1. The protection circuit of the power utilization loop is characterized by comprising a first switch circuit, a second switch circuit, a control unit and an information acquisition unit; the on-off response speed of the second switch circuit is faster than that of the first switch circuit;

the first end of the first switch circuit is connected with the control unit, the second end of the first switch circuit is connected with a power supply in the power utilization loop, and the third end of the first switch circuit is connected with a load in the power utilization loop; the control unit is connected with the information acquisition unit;

the first end of the second switch circuit is connected with the control unit, the second end of the second switch circuit is connected between the third end of the first switch circuit and the load in the power utilization loop, and the third end of the second switch circuit is respectively connected with the power supply in the power utilization loop and the load in the power utilization loop, or the third end of the second switch circuit is grounded.

2. The protection circuit of the power consumption circuit according to claim 1, wherein the second switching circuit comprises a first MOS transistor and a second MOS transistor;

the grid electrode of the first MOS tube and the grid electrode of the second MOS tube are connected with the control unit; the drain electrode of the first MOS tube is connected with the third end of the first switch circuit, and the source electrode of the first MOS tube is connected with the source electrode of the second MOS tube; and the drain electrode of the second MOS tube is respectively connected with a power supply in the power utilization loop and a load in the power utilization loop, or the drain electrode of the second MOS tube is grounded.

3. The protection circuit of an electrical circuit according to claim 1, wherein the information acquisition unit comprises a leakage current detection unit;

the first end of the leakage current detection unit is connected with the control unit, the second end of the leakage current detection unit is connected between the second end of the second switch circuit and the load in the power utilization circuit, and the third end of the leakage current detection unit is connected between the third end of the second switch circuit and the load in the power utilization circuit.

4. A protection circuit for an electrical circuit according to claim 3, wherein the information acquisition unit further comprises a short circuit detection unit;

the first end of the short circuit detection unit is connected with the control unit, the second end of the short circuit detection unit is connected with the second end of the second switch circuit, and the third end of the short circuit detection unit is connected with the second end of the leakage current detection unit.

5. The protection circuit of an electrical circuit according to claim 4, wherein the information acquisition unit further comprises a surge detection unit;

the first end of the surge detection unit is connected with the control unit, the second end of the surge detection unit is connected with the second end of the first switch circuit, and the third end of the surge detection unit is connected with the third end of the second switch circuit.

6. The protection circuit of an electrical circuit of claim 1, further comprising a reactance protection unit;

the reactance protection unit has a first end connected between the second end of the first switching circuit and the power supply in the power consumption loop, and a second end connected between the third end of the second switching circuit and the power supply in the power consumption loop.

7. The protection circuit of an electrical circuit of claim 6, wherein the reactance protection unit comprises a reactance unit, a first resistor, a second resistor, and a capacitance unit;

the first end of the reactance unit is respectively connected with a power supply in the power utilization loop and the first end of the first resistor, and the second end of the reactance unit is respectively connected with the second end of the first switch circuit and the first end of the second resistor;

the first end of the capacitor unit is connected with the second end of the first resistor, the second end of the capacitor unit is connected with the second end of the second resistor, and the third end of the capacitor unit is connected between the third end of the second switch circuit and a power supply in the power utilization loop.

8. A protection circuit for an electrical circuit according to any of claims 1 to 7, wherein the number of second switching circuits is at least two, and wherein a third terminal of at least one of the second switching circuits is grounded.

9. A protection circuit for an electrical circuit according to any one of claims 1 to 7, wherein the first switching circuit is a mechanical circuit breaker or a permanent magnet circuit breaker.

10. A protection system for an electrical circuit, comprising a service unit and a protection circuit for an electrical circuit according to any one of claims 1 to 9;

the service unit is in wireless connection with the control unit in the protection circuit.