CN221080919U - Excitation surge current suppression system - Google Patents

Abstract

The utility model provides a magnetizing inrush current suppression system, which comprises a main circuit power supply, a circuit breaker QF1, a magnetizing inrush current suppression device LC1, a voltage regulating device and a load RL1, wherein the main circuit power supply, the circuit breaker QF1, the magnetizing inrush current suppression device LC1, the voltage regulating device and the load RL1 are sequentially connected, the magnetizing inrush current suppression device LC1 comprises an input terminal CN1 and an output terminal CN2, the input terminal CN1 and the output terminal CN2 are arranged on the magnetizing inrush current suppression device LC1, the input terminal CN1 is respectively connected with the output end of the circuit breaker QF1 and a ground wire PE, the output terminal CN2 is respectively connected with a live wire zero line of the input side of the voltage regulating device, and the live wire and the zero line of the output side of the voltage regulating device are respectively connected with a live wire zero line of the load RL 1; the excitation surge suppression system can effectively simplify the structure of the excitation surge suppression system, reduce the cost of the excitation surge suppression system, improve the protection force of the excitation surge suppression system on the isolation transformer and the voltage regulator, and avoid the influence of the excitation surge on the isolation transformer and the voltage regulator.

Description

Excitation surge current suppression system

Technical Field

The utility model relates to the technical field of electronic circuits, in particular to a magnetizing inrush current suppression system.

Background

The isolation transformer can better protect the life safety of human beings because the primary side and the secondary side are completely electrically isolated, and is widely applied to the fields of various industrial production, medical equipment, computer networks, special environments and the like; however, at the moment of closing, the isolation transformer can generate exciting inrush current with the current value of 6 to 8 times or more than the rated current for hundreds of milliseconds, so that the input side breaker trips, or the input side UPS, the inverter and the like perform equipment protection; isolating the exciting surge of the transformer increases the switching-on times of the circuit breaker, and possibly causes damage to equipment such as UPS or an inverter; the voltage regulator has the same characteristics as the isolation transformer.

At present, the traditional scheme has the following defects of increasing the selection of electric equipment such as an input side breaker, a UPS, an inverter and the like: 1. the application cost is increased; 2. after the output side equipment is over-current, the input side equipment is damaged due to the fact that the input side equipment is too large to be protected or is not protected timely, so that research on how to improve the stability of excitation inrush current inhibition of an isolation transformer and a voltage regulator and reduce the cost of the excitation inrush current inhibition has important significance.

In patent CN109245047a, a 110kV transformer excitation surge suppression device and suppression method are mentioned, including a fast switch and a controller system, where the fast switch is connected between the high-voltage side of the 110kV transformer and the isolating switch, and the controller system controls the opening and closing operation of the fast switch, so that the excitation surge can be limited, the protection malfunction is eliminated, the electric energy quality is improved, and the operation reliability of equipment and power grid is improved, but because the excitation surge suppression device is only applicable to a 110kV power system, the application range of the suppression mode is smaller.

In patent CN103180926a, there is mentioned an inrush current suppressing device adapted to a structure in which a circuit breaker is connected between a power supply and a transformer for suppressing an inrush current due to a closing operation of the transformer, comprising: a power supply voltage measurement unit that measures a power supply voltage on the power supply side of the circuit breaker; a residual magnetic flux calculating unit that stores a breaking characteristic of the circuit breaker during breaking and a decay characteristic of a magnetic flux of the transformer after current breaking, calculates a current-breaking magnetic flux based on the power supply voltage and the breaking characteristic, and calculates a residual magnetic flux based on the current-breaking magnetic flux and the decay characteristic; an on-phase calculation unit that calculates a power supply voltage phase at which the residual magnetic flux matches a steady-state magnetic flux when the power supply voltage is applied, and uses the calculated power supply voltage phase as an on-power supply voltage phase; and a control unit that performs closing control to turn on the circuit breaker at the on-power voltage phase, wherein the suppression device can suppress the magnetizing inrush current caused by the inconsistency between the residual magnetic flux and the steady-state magnetic flux, but the suppression device is provided between the circuit breaker and the power grid, which is liable to cause a problem of low safety.

Disclosure of utility model

In view of the above, the present utility model aims to provide a magnetizing inrush current suppression system, so as to solve the problems of the prior art that the isolation transformer or voltage regulator is susceptible to the impact of a magnetizing inrush current, and causes tripping of a circuit breaker or frequent closing of the circuit breaker, thereby affecting the use safety of a load, and the existing magnetizing inrush current suppression device has high cost and poor protection force; therefore, the structure of the excitation surge suppression system can be effectively simplified, the cost of the excitation surge suppression system is reduced, the protection force of the excitation surge suppression system on the isolation transformer and the voltage regulator is improved, and the influence of the excitation surge on the isolation transformer and the voltage regulator is avoided; under the conditions of voltage sag and short interruption, the excitation surge suppression system can be rapidly disconnected and rapidly re-commissioned, and the excitation surge impact under the conditions is prevented.

In order to achieve the above purpose, the technical scheme of the utility model is realized as follows:

The utility model relates to a magnetizing inrush current suppression system, which comprises a main circuit power supply, a circuit breaker QF1, a magnetizing inrush current suppression device LC1, a voltage regulating device and a load RL1, wherein the main circuit power supply, the circuit breaker QF1, the magnetizing inrush current suppression device LC1, the voltage regulating device and the load RL1 are sequentially connected, the magnetizing inrush current suppression device LC1 comprises an input terminal CN1 and an output terminal CN2, the input terminal CN1 and the output terminal CN2 are respectively arranged on the magnetizing inrush current suppression device LC1, the input terminal CN1 is respectively connected with the output end of the circuit breaker QF1 and a ground wire PE, the output terminal CN2 is respectively connected with a live wire and a zero wire on the input side of the voltage regulating device, the live wire and the zero wire on the output side of the voltage regulating device are respectively connected with the live wire and the zero wire on the load RL1, and the magnetizing inrush current of the voltage regulating device is suppressed through the effect of the magnetizing inrush current suppression device LC 1.

Further, the voltage regulating device is an isolation transformer T1 or a voltage regulator.

Further, the main power supply includes a live wire L and a neutral wire N, the input terminal CN1 includes an input one terminal CN11, an input two terminal CN12 and an input three terminal CN13, the live wire L is connected with the input one terminal CN11 through the breaker QF1, the neutral wire N is connected with the input three terminal CN13 through the breaker QF1, and the input two terminal CN12 is connected with the ground wire PE.

Further, the excitation surge suppression device LC1 further comprises a relay K1 contact switch and a power resistor R1, wherein the excitation surge suppression device LC1 is arranged on the live wire L in series, and the power resistor R1 is arranged at two ends of the relay K1 contact switch in parallel and used for suppressing excitation surge.

Further, excitation surge suppression device LC1 still includes power module, first regulating module and second regulating module, after power module input live wire and first regulating module input side live wire are parallelly connected, be connected with main circuit power's live wire L, power module input zero line is parallelly connected with first regulating module input side zero line after, be connected with main circuit power's zero line N, the second regulating module input sets up on main circuit power live wire L, be used for playing the suggestion effect under the unusual situation of excitation surge suppression device LC1, relay K1 contact switch and power resistance R1 all set up between power module and first regulating module's positive pole, second regulating module.

Further, the power supply module comprises an alternating current-direct current conversion two module D2 and a linear voltage stabilizer LDO, the positive electrode and the negative electrode of the input end of the alternating current-direct current conversion two module D2 are respectively connected with a live wire L and a zero line N of a main power supply, the positive electrode of the output end of the alternating current-direct current conversion two module D2 is respectively connected with the positive electrode of the input end of the linear voltage stabilizer LDO and a power supply Vcc, the negative electrode of the output end of the alternating current-direct current conversion two module D2 is respectively connected with the negative electrode of the input end of the linear voltage stabilizer LDO and a ground GND, and the positive electrode and the negative electrode of the output end of the linear voltage stabilizer LDO are respectively connected with a reference voltage Verf and the ground GND.

Further, the power supply module further includes a fifth capacitor C5, the fifth capacitor C5 is disposed between the ac-dc conversion module D2 and the linear regulator LDO, the positive electrode of the fifth capacitor C5 is connected to the power supply Vcc and the positive electrode of the output end of the ac-dc conversion module D2, and the negative electrode of the fifth capacitor C5 is connected to the negative electrode of the output end of the ac-dc conversion module D2 and the ground GND, respectively.

Further, the power supply module further comprises a sixth capacitor C6, the positive electrode of the sixth capacitor C6 is respectively connected with the positive electrode of the LDO output end of the linear voltage stabilizer and the reference voltage Verf, and the negative electrode of the sixth capacitor C6 is respectively connected with the negative electrode of the LDO output end of the linear voltage stabilizer and the ground GND.

Further, the excitation surge suppression device LC1 further comprises a switching-on display lamp LED1, an overcurrent display lamp LED2, a first potentiometer RT1 and a second potentiometer RT2, wherein the switching-on display lamp LED1, the first potentiometer RT1 and the second potentiometer RT2 are connected with the first adjusting module, and the overcurrent display lamp LED2 is connected with the second adjusting module.

Further, the first regulating module comprises a transformer T2 and a relay K1 coil control circuit, the output side of the transformer T2 is connected with the relay K1 coil control circuit, and the input side of the transformer T2 is connected with the output side of the circuit breaker QF 1.

Compared with the prior art, the excitation surge current suppression system provided by the utility model has the following components

The beneficial effects are that:

The suppression system can effectively simplify the structure of the excitation surge suppression system, reduce the cost of the excitation surge suppression system, improve the protection force of the excitation surge suppression system on the isolation transformer and the voltage regulator, and avoid the influence of the excitation surge on the isolation transformer and the voltage regulator; under the conditions of voltage sag and short interruption, the excitation surge suppression system can be rapidly disconnected and rapidly re-commissioned, and excitation surge impact under the condition is prevented.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description serve to explain the utility model. In the drawings:

FIG. 1 is a schematic diagram of a surge suppression device;

Fig. 2 is a schematic diagram of an internal circuit of the inrush current suppression apparatus.

Reference numerals illustrate: 1. a main power supply; 2. a pressure regulating device; 3. a power supply module; 4. a first adjustment module; 5. and a second adjustment module.

Detailed Description

The inventive concepts of the present disclosure will be described below using terms commonly used by those skilled in the art to convey the substance of their work to others skilled in the art. These inventive concepts may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

It should be noted that, without conflict, the embodiments of the present utility model and features of the embodiments may be combined with each other.

The utility model will be described in detail below with reference to the drawings in connection with embodiments.

This embodiment is directed to an electronic circuit, and is identical to a conventional electronic circuit in that the overall structure is composed of wires and a transformer.

In the prior art, at the moment of closing, an isolation transformer or a voltage regulator can generate exciting inrush current with the current value of 6 to 8 times or higher than rated current for hundreds of milliseconds, so that an input side breaker trips, or an input side UPS, an inverter and the like perform equipment protection; the isolation transformer excitation surge current increases the switching-on times of the breaker and possibly causes equipment damage such as a UPS or an inverter, and the traditional solution is to increase the type selection of the input side breaker, the UPS, the inverter and other electrical equipment.

In order to solve the problem that in the prior art, the isolating transformer or the voltage regulator is easy to be impacted by exciting current, so that the tripping of the circuit breaker or the frequent closing of the circuit breaker is caused, the use safety of a load is further affected, and the problems of higher cost and poorer protection force of the existing exciting current inhibiting device are solved; the embodiment provides a magnetizing inrush current suppression system, which comprises a main circuit power supply 1, a circuit breaker QF1, a magnetizing inrush current suppression device LC1, a voltage regulating device 2 and a load RL1, wherein the main circuit power supply 1, the circuit breaker QF1, the magnetizing inrush current suppression device LC1, the voltage regulating device 2 and the load RL1 are sequentially connected, the magnetizing inrush current suppression device LC1 comprises an input terminal CN1 and an output terminal CN2, the input terminal CN1 and the output terminal CN2 are respectively arranged on the magnetizing inrush current suppression device LC1, the input terminal CN1 is respectively connected with an output end of the circuit breaker QF1 and a ground wire PE, the output terminal CN2 is respectively connected with an input side live wire and a zero wire of the voltage regulating device 2, the output side live wire and the zero wire of the voltage regulating device 2 are respectively connected with a live wire and a zero wire of the load RL1, and the magnetizing inrush current of the voltage regulating device 2 is suppressed by the magnetizing inrush current of the voltage regulating device LC1, wherein the voltage regulating device 2 is an isolation transformer T1 or a voltage regulator, and the input and output respectively refer to a current input end and a current output end in the embodiment.

Through the cooperation setting of circuit breaker QF1, excitation surge suppression device LC1, voltage regulating device 2, can effectually simplify the structure of excitation surge suppression system, reduce the cost of excitation surge suppression system, improve the protection dynamics of excitation surge suppression system to isolation transformer, voltage regulator, avoid the influence of excitation surge to isolation transformer, voltage regulator.

The main power supply 1 comprises a live wire L and a zero line N, wherein the input terminal CN1 comprises an input one terminal CN11, an input two terminal CN12 and an input three terminal CN13, the live wire L is connected with the input one terminal CN11 through a breaker QF1, the zero line N is connected with the input three terminal CN13 through the breaker QF1, and the input two terminal CN12 is connected with a ground wire PE; the output terminal CN2 comprises an output one terminal CN21 and an output two terminal CN22, and the output one terminal CN21 and the output two terminal CN22 are respectively connected with the positive electrode and the negative electrode of the isolation transformer T1 or the input side of the voltage regulator; the excitation surge suppression device LC1 further comprises a relay K1 contact switch and a power resistor R1, wherein the excitation surge suppression device LC1 is arranged on the live wire L in series, and the power resistor R1 is arranged at two ends of the relay K1 contact switch in parallel and used for suppressing excitation surge; specifically, a main line live wire L and a zero line N are connected with an input terminal CN1 of an excitation surge suppression device LC1 through a breaker QF1, wherein CN11 is connected with an output L1 main line of the breaker QF1, CN13 is connected with an output N1 main line of the breaker QF1, and CN12 is connected with the ground; the exciting surge suppressing device LC1 output terminal CN2 is connected with the isolation transformer T1, CN21 is connected with the L terminal of the isolation transformer T1 or the voltage regulator, CN22 is connected with the N terminal of the isolation transformer T1 or the voltage regulator, in addition, the exciting surge suppressing device LC1 further comprises a first safety capacitor C01, a second safety capacitor C02, a third safety capacitor C03 and a piezoresistor RV1, the main line of the output L1 of the circuit breaker QF1 is respectively connected with the input ends of the C01, the C02, the C03 and the RV1, the output ends of the C01 and the RV1 are respectively connected with the main line of the output N1 of the circuit breaker QF1, the output ends of the C02 and the C03 are uniformly connected with PE ground wires, and the output end of the C01 is connected with the negative electrode of the input side of the power supply module 3.

Through the arrangement of the main power supply 1, the excitation surge suppressing device LC1 and the system structure of the isolation transformer T1 or the voltage regulator, the influence of the excitation surge on the isolation transformer T1 or the voltage regulator can be effectively simplified, the safety of the isolation transformer T1 or the voltage regulator is improved, the operation stability and the reliability of the isolation transformer T1 or the voltage regulator are enhanced, in addition, the RV1 piezoresistor has the functions of lightning protection and overvoltage protection, the first safety capacitor C01 is used for suppressing input side differential mode interference, and the second safety capacitor C02 and the third safety capacitor C03 are used for suppressing input side common mode interference.

The excitation surge suppression device LC1 further comprises a power supply module 3, a first adjusting module 4 and a second adjusting module 5, wherein an input end live wire of the power supply module 3 is connected with a live wire L of the main circuit power supply 1 after being connected in parallel with an input side live wire of the first adjusting module 4, a zero wire of the input end of the power supply module 3 is connected with a zero wire N of the main circuit power supply 1 after being connected in parallel with the input side zero wire of the first adjusting module 4, and an input end of the second adjusting module 5 is arranged on the live wire L of the main circuit power supply 1 and used for playing a prompting role under the abnormal condition of the excitation surge suppression device LC1, and a relay K1 contact switch and a power resistor R1 are arranged between the power supply module 3 and an anode of the first adjusting module 4 and between the relay K1 and the second adjusting module 5.

The power resistor R1 is used for inhibiting exciting inrush current, the relay K1 contact switch is used for controlling a circuit under the control of the first regulating module 4, the power supply module 3 is used for supplying power of different types for the circuits in the first regulating module 4 and the second regulating module 5, and the first regulating module 4 and the second regulating module 5 are convenient for comparing the real-time condition of the main circuit power supply 1 in the modules and then carrying out conversion reminding of corresponding indicator lamps or realizing the purpose of inhibiting exciting inrush current by regulating the closing time of the relay K1.

The power supply module 3 comprises an alternating current-direct current conversion two module D2 and a linear voltage regulator LDO, the positive electrode and the negative electrode of the input end of the alternating current-direct current conversion two module D2 are respectively connected with a live wire L and a zero line N of the main power supply 1, the positive electrode of the output end of the alternating current-direct current conversion two module D2 is respectively connected with the positive electrode of the input end of the linear voltage regulator LDO and a power supply Vcc, the negative electrode of the output end of the alternating current-direct current conversion two module D2 is respectively connected with the negative electrode of the input end of the linear voltage regulator LDO and a ground GND, and the positive electrode and the negative electrode of the output end of the linear voltage regulator LDO are respectively connected with a reference voltage Verf and the ground GND; the power supply module 3 further comprises a fifth capacitor C5, the fifth capacitor C5 is arranged between the AC-DC conversion two module D2 and the linear voltage regulator LDO, the positive electrode of the fifth capacitor C5 is respectively connected with the power supply Vcc and the positive electrode of the output end of the AC-DC conversion two module D2, and the negative electrode of the fifth capacitor C5 is respectively connected with the negative electrode of the output end of the AC-DC conversion two module D2 and the ground GND; the power supply module 3 further includes a sixth capacitor C6, where the positive electrode of the sixth capacitor C6 is connected to the positive electrode of the output terminal of the LDO of the linear voltage regulator and the reference voltage Verf, and the negative electrode of the sixth capacitor C6 is connected to the negative electrode of the output terminal of the LDO of the linear voltage regulator and the ground GND, and in this embodiment, the AC-DC conversion two modules D2 are AC-DC switching power supplies.

The power supply VCC and the power supply Vref are respectively obtained by an AC-DC switching power supply and a linear voltage regulator LDO, the fifth capacitor C5 and the sixth capacitor C6 can play a role in filtering, so that the power supply stability of the power supply module 3 is improved, the generation of interference signals is reduced, and the accuracy of adjustment of the first adjusting module 4 and the second adjusting module 5 is improved.

The excitation surge suppression device LC1 further comprises a switching-on display lamp LED1, an overcurrent display lamp LED2, a first potentiometer RT1 and a second potentiometer RT2, wherein the switching-on display lamp LED1, the first potentiometer RT1 and the second potentiometer RT2 are connected with the first adjusting module 4, and the overcurrent display lamp LED2 is connected with the second adjusting module 5.

The first potentiometer RT1 in the excitation surge suppression device LC1 is used for adjusting the closing time of the relay K1 in the device; according to the characteristics of different isolation transformers T1, the time of occurrence of exciting inrush current and the duration of the exciting inrush current in the power-on process are different (the time is changed within hundreds of milliseconds); in the actual application process, voltage sag and short interruption are considered according to different safety standard requirements, and the closing time of the relay K1 is changed by adjusting the first potentiometer RT1, so that the aim of inhibiting excitation surge current is fulfilled; the second potentiometer RT2 in the excitation surge suppression device LC1 is used for adjusting the off time of the relay K1 after power failure or voltage sag; in the actual application process, according to different standard safety requirements, voltage sag and short interruption are considered, and the switching-off time of the relay K1 is changed by adjusting the second potentiometer RT 2. And after the power supply is restored again, the aim of inhibiting the excitation surge current is fulfilled.

The first regulating module 4 comprises a transformer T2 and a relay K1 coil control circuit, wherein the output side of the transformer T2 is connected with the relay K1 coil control circuit, the input side of the transformer T2 is connected with the output side of the circuit breaker QF1, the input side of the transformer T2 is specifically connected with the L1 main line and the N1 main line respectively, the relay K1 coil control circuit comprises an alternating current-direct current conversion module D1, a first-stage comparator N1A and a second-stage comparator N1B, the output side of the transformer T2, the alternating current-direct current conversion module D1, the first-stage comparator N1A and the second-stage comparator N1B are sequentially connected, the positive electrode of the input side of the transformer T2 is respectively connected with the positive electrode of a contact switch of the relay K1, the positive electrode of the power supply module 3 and the live wire L, the negative electrode of the input side of the transformer T2 is respectively connected with the negative electrode of the power supply module 3 and the zero line N, and the output end of the second-stage comparator N1B is connected with the switching-on display lamp LED1, and the alternating current-direct current conversion module D1 is an alternating current-direct current converter; specifically, the first adjusting module 4 further includes a first capacitor C1, an eleventh resistor R11, a twelfth resistor R12, a second capacitor C2, a thirteenth resistor R13, a sixteenth resistor R16, a fourteenth resistor R14, a diode D11, a diode D12, a fifteenth resistor R15, a twenty-first resistor R21, a second potentiometer RT2, a third capacitor C3, a fourth capacitor C4, a first potentiometer RT1, a seventeenth resistor R17, an eighteenth resistor R18, a nineteenth resistor R19, a twentieth resistor R20, and an electronic switch MOS1, where the output ends of the first capacitor C1, the twelfth resistor R12, the second capacitor C2, the sixteenth resistor R16, and a zero line on the output side of the ac-dc conversion module D1 are connected in parallel, and after the input ends of the first capacitor C1, the twelfth resistor R12, the second capacitor C2 are connected in parallel, the input end of a sixteenth resistor R16 is connected with an N1A negative electrode terminal 2 after being connected with an output end of a thirteenth resistor R13 in parallel, the input end of the R13 is connected with Verf, the output end of the R14 is connected with an input end of C3 and C4 after being connected with an N1B positive electrode terminal 5 after being connected with an output end of R21 in parallel sequentially through D11, D12 and RT2, the input end of the R21 is connected with an input end of the R1B after being connected with an output end of the C3 and C4 oppositely, the negative electrode of the D11 is arranged opposite to the negative electrode of the D12, the input end of the R21 is connected with an output end of the R15 and an output end of the N1A terminal 1 respectively, the input end of the R15 is connected with the power supply terminal of the N1A in parallel and then connected with Vcc, and the ground end of the N1A is connected with the output end of the R16 in parallel;

The output ends of C3, C4 and RT1 are connected in parallel, the input end of RT1 is connected with the output ends of N1B negative electrode terminals 6 and R17 respectively, the input end of R17 is connected with Vref, the terminal 7 of N1B is connected with the input end of R19 and the output end of R18 respectively, the input end of R18 is connected with Vcc, the output end of R19 is connected with the input end of R20 and the grid electrode of MOS1 respectively, the output end of R20 is connected with the source electrode of MOS1 in parallel, the drain electrode of MOS1 is connected with Vcc through the coil of a relay K1 and a closing display lamp LED1, in particular, D1 is a rectifier bridge, alternating current is converted into direct current, the direct current is filtered through an electrolytic capacitor C1, R11 and R12 are divided, a voltage signal is sent to the positive electrode terminal 3 of the input side of a comparator N1A, the reference voltage is compared with the negative electrode terminal 2 of the input side of the comparator N1A, the reference voltage Vref is obtained through the voltage division of resistors R13 and R16, R14 and D11 are used for being used as the voltage value of the comparator N1A for recycling, and when the output side of the comparator N1A is 0, the positive electrode signal of the comparator is obtained through the resistors R11 and R12 are commonly; when the output side of the comparator N1A is VCC, the signal of the positive terminal 3 of the comparator N1A is obtained by dividing the voltage by the resistors R11 and R12, C3 and R21 form an RC charging circuit, when the output side of the comparator N1A is changed from low level to high level, the RC is a slow charging change process, after the voltage signal is connected to the positive terminal 5 of the secondary comparator N1B, the voltage signal is compared with the reference voltage of the negative terminal 6 of the input side of the secondary comparator N1B, the voltage Vref is divided by the resistor R11 and the potentiometer RT1 to obtain the reference voltage Vref2, RT1 is adjusted, the reference voltage Vref2 is changed, when the positive terminal 5 of the N1B is larger than the negative terminal 6 of the N1B, the output side of the N1B is changed from low level to high level, MOS1 is controlled to be opened by R19, the relay K1 coil is turned on, the LED1 indicates the lamp is on, and the K1 contact is closed, and the excitation current is inhibited at this time; when the main power is disconnected, the input positive terminal 3 of the N1A comparator is changed into 0, the output end of the N1A comparator is changed from high level to low level, the capacitor C3 is rapidly discharged through the diode D12 and the potentiometer RT2, the output side of the second-stage comparator N1B is changed from high level to low level, the MOS1 is closed, and then the contact of the relay K1 is rapidly disconnected; the discharging time can be adjusted by adjusting the potentiometer RT2, so that the switching-off time of the relay K1 is adjusted; in this embodiment, the LED1 is green light, the LED2 is red light, and the present invention is not limited thereto, and the transformer T2 is a low-power transformer according to the required setting.

The contact switch of the relay K1 in the excitation surge suppression device LC1 is closed, and the green indicator light LED1 is normally on; if the breaker QF1 is closed and then the indicator light LED1 is not on, the fact that the relay K1 is not closed and the exciting inrush current suppression device LC1 is needed to be subjected to outage checking is indicated, the exciting inrush current suppression device LC1 is prevented from being burnt out after the load RL1 on the output side of the isolation transformer is started, then the protection effect on T1 or the voltage regulator is achieved, the protection effect on the exciting inrush current suppression device LC1 can be achieved, the safety of a system structure for suppressing exciting inrush current is guaranteed, the stability of a system for suppressing exciting inrush current is improved, the reliability of the system is greatly improved, and the anti-risk capability of the system for coping with exciting inrush current is guaranteed.

The second regulating module 5 comprises a thirty-first resistor R31, a thirty-second resistor R32, a third capacitor C31, a thirty-third resistor R33, a thirty-fourth resistor R34, a thirty-fifth resistor R35, a thirty-sixth resistor R36, a thirty-seventh resistor R37, a thirty-eighth resistor R38, a comparator N31, a diode D31, a triode Q31 and a current transformer I1, wherein the I1 is arranged on a live wire L of the main power supply 1, a terminal Iout1 of the I1 is connected with an input end of the R32 and the C31 in parallel and then is respectively connected with an input end of the R32 and an input end of the C31 in parallel, a terminal Gnd of the I1 is respectively connected with an output end of the R32, the C31 and the R34 in parallel and then is grounded, an input end of the R34 is respectively connected with an output end of the R33 and an input end of the N31 in a negative terminal 2, an input end of the R33 is connected with Verf, an input end of the N31 is respectively connected with an output end of the D31 and an output end of the R35, an input end of the R36 is connected with Vcc, the output end of R37 and the emitter of Q31 are connected in parallel, the collector of Q31 is connected with Vcc through R38 and LED2 in sequence, the negative electrode of LED2 is arranged towards R38, specifically, in order to more effectively adjust and restrain excitation surge time, a secondary side current signal Iout of a current transformer I1 is converted into a voltage signal through resistors R31 and R32 to a positive terminal 3 of a comparator N31, then the voltage signal Iout is compared with the reference voltage of a negative terminal 2 at the input side of a comparator N1B, the voltage Vref is divided by a resistor R33 and a potentiometer R34 to obtain a reference voltage Vref3, when overcurrent occurs in a main circuit, the comparator N3 is inverted, the output side is changed from low level to high level, the high level is maintained through a diode D31, the triode collector is conducted to the emitter through a resistor R36 and the base electrode of an NPN triode Q31, the red indicator lamp LED2 is normally on, the character that the restraint excitation surge time is unsuitable, and the current requirement is further adjusted RT 1; in the present embodiment of the present invention, in the present embodiment, because the voltage regulator and the isolation transformer T1 have the same characteristics, the system is also applicable to the voltage regulator, and in addition, aiming at different test standards, voltage sag and short-time terminal standards are different, and the standard requirements are met by adjusting RT1 and RT 2; during the voltage sag, the voltages VCC and Vref should remain unchanged.

After the excitation surge suppression device LC1 is put into use, the red indicator lamp LED2 is normally on, so that when the excitation surge of the isolation transformer occurs, the relay K1 in the excitation surge suppression device LC1 is already closed, and the excitation surge suppression effect is not achieved; the potentiometer RT1 is required to be adjusted, the closing time of the relay K1 is changed, and the excitation surge current is restrained; in addition, the system has the advantages that the system is simple in structure, the problem of exciting inrush current of the isolation transformer T1 or the voltage regulator is effectively restrained, the price is low, the use is convenient, the arrangement of the I1 current transformer can be used for sampling main current and judging whether the device is overcurrent or not, and further, the system is beneficial to solving the problem that the isolation transformer T1 and the voltage regulator are easily affected by the exciting inrush current.

In the present utility model, any electronic circuit may include a structure of the excitation surge suppression system described in the present embodiment, and on the basis of the related structures and the assembly relationships of the excitation surge device, the potentiometer, and the comparator provided in the present embodiment, the electronic circuit further includes conventional components including a wire, a transformer, and the like, which are not described herein in detail in view of the fact that they are all related technologies.

The foregoing description of the preferred embodiments of the utility model is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the utility model.

Claims (10)

1. The excitation surge suppression system is characterized by comprising a main circuit power supply (1), a circuit breaker QF1, an excitation surge suppression device LC1, a voltage regulating device (2) and a load RL1, wherein the main circuit power supply (1), the circuit breaker QF1, the excitation surge suppression device LC1, the voltage regulating device (2) and the load RL1 are sequentially connected, the excitation surge suppression device LC1 comprises an input terminal CN1 and an output terminal CN2, the input terminal CN1 and the output terminal CN2 are respectively arranged on the excitation surge suppression device LC1, the input terminal CN1 is respectively connected with the output end of the circuit breaker QF1 and a ground wire PE, the output terminal CN2 is respectively connected with a live wire and a zero wire on the input side of the voltage regulating device (2), the live wire and the zero wire on the output side of the voltage regulating device (2) are respectively connected with the live wire and the zero wire of the load RL1, and the excitation surge suppression of the voltage regulating device (2) is realized through the effect of the excitation surge suppression device LC 1.

2. The inrush current suppression system according to claim 1, characterized in that the voltage regulating device (2) is an isolation transformer T1 or a voltage regulator.

3. The inrush current suppression system according to claim 2, characterized in that the main power supply (1) includes a live wire L and a neutral wire N, the input terminal CN1 includes an input one terminal CN11, an input two terminal CN12 and an input three terminal CN13, the live wire L is connected to the input one terminal CN11 through the circuit breaker QF1, the neutral wire N is connected to the input three terminal CN13 through the circuit breaker QF1, and the input two terminal CN12 is connected to the ground wire PE.

4. A magnetizing inrush current suppression system according to claim 3, characterized in that the magnetizing inrush current suppression device LC1 further comprises a relay K1 contact switch and a power resistor R1, the magnetizing inrush current suppression device LC1 is serially arranged on the live line L, and the power resistor R1 is parallelly arranged at two ends of the relay K1 contact switch for suppressing the magnetizing inrush current.

5. The excitation surge suppression system according to claim 4, wherein the excitation surge suppression device LC1 further comprises a power supply module (3), a first adjusting module (4) and a second adjusting module (5), wherein an input live wire of the power supply module (3) is connected with a live wire L of the main power supply (1) after being connected in parallel with an input live wire of the first adjusting module (4), an input zero wire of the power supply module (3) is connected with a zero wire N of the main power supply (1) after being connected in parallel with an input zero wire of the first adjusting module (4), and an input end of the second adjusting module (5) is arranged on the live wire L of the main power supply (1) and is used for playing a prompting role under abnormal conditions of the excitation surge suppression device LC1, and a contact switch of the relay K1 and the power resistor R1 are arranged between the power supply module (3) and a positive electrode of the first adjusting module (4) and between the relay K1 and the second adjusting module (5).

6. The excitation surge suppression system according to claim 5, wherein the power supply module (3) comprises an ac-dc conversion two-module D2 and a linear voltage regulator LDO, the positive and negative poles of the input end of the ac-dc conversion two-module D2 are respectively connected with the live wire L and the zero wire N of the main power supply (1), the positive pole of the output end of the ac-dc conversion two-module D2 is respectively connected with the positive pole of the input end of the linear voltage regulator LDO and the power supply Vcc, the negative pole of the output end of the ac-dc conversion two-module D2 is respectively connected with the negative pole of the input end of the linear voltage regulator LDO and the ground GND, and the positive and negative poles of the output end of the linear voltage regulator LDO are respectively connected with the reference voltage Verf and the ground GND.

7. The excitation surge current suppression system according to claim 6, wherein the power supply module (3) further includes a fifth capacitor C5, the fifth capacitor C5 is disposed between the ac-dc conversion two module D2 and the linear regulator LDO, the positive electrode of the fifth capacitor C5 is connected to the power supply Vcc and the positive electrode of the output end of the ac-dc conversion two module D2, respectively, and the negative electrode of the fifth capacitor C5 is connected to the negative electrode of the output end of the ac-dc conversion two module D2 and the ground GND, respectively.

8. The inrush current suppression system according to claim 6, wherein the power supply module (3) further includes a sixth capacitor C6, the positive electrode of the sixth capacitor C6 is connected to the positive electrode of the LDO output terminal of the linear voltage regulator and the reference voltage Verf, and the negative electrode of the sixth capacitor C6 is connected to the negative electrode of the LDO output terminal of the linear voltage regulator and the ground GND, respectively.

9. The magnetizing inrush current suppression system according to claim 5, wherein the magnetizing inrush current suppression device LC1 further comprises a closing display lamp LED1, an overcurrent display lamp LED2, a first potentiometer RT1 and a second potentiometer RT2, wherein the closing display lamp LED1, the first potentiometer RT1 and the second potentiometer RT2 are all connected with the first adjusting module (4), and the overcurrent display lamp LED2 is connected with the second adjusting module (5).

10. The inrush current suppression system according to claim 9, characterized in that the first regulation module (4) includes a transformer T2 and a relay K1 coil control circuit, an output side of the transformer T2 is connected to the relay K1 coil control circuit, and an input side of the transformer T2 is connected to an output side of the circuit breaker QF 1.