A circuit breaker opening and closing electromagnet control method, device and system

Abstract

The application discloses a circuit breaker opening and closing electromagnet control method, device and system. The method comprises the following steps: collecting voltage data, current data and displacement data of an electromagnet in the process of opening and closing of a circuit breaker in real time within a preset period; determining the theoretical acceleration of an iron core at each moment within the preset period based on the voltage data and the current data, and determining the actual acceleration of the iron core at each moment within the preset period based on the displacement data; and adjusting the excitation current of the electromagnet or adjusting the excitation current and the excitation time of the electromagnet based on the actual acceleration and the theoretical acceleration at each moment. Thus, whether the resistance of the iron core is abnormal can be monitored, and the success rate of opening and closing can be maximized.

Description

Technical Field

[0001] This application relates to the field of circuit breaker control technology, and in particular to a method, device and system for controlling the opening and closing electromagnets of a circuit breaker. Background Technology

[0002] Electricity is an essential energy source for industrial development, and the power industry is evolving from traditional energy supply towards cleaner and smarter energy sources. With the large-scale grid connection of new energy sources such as photovoltaics, the issue of grid stability is becoming increasingly prominent. As the connection between the power grid and users, the distribution network directly impacts power quality. Numerous vacuum circuit breakers exist in the distribution network; these breaker control and protect the network through opening and closing operations, playing a crucial role in ensuring its stable operation. The principle of circuit breaker opening and closing is as follows: energizing the opening and closing coils causes the electromagnet core to strike the latch, triggering the energy storage mechanism to release its stored energy, which in turn actuates the operating mechanism to open and close the contact system. The core impact is not the power source for the circuit breaker's operation, but only serves as a trigger source; sufficient instantaneous impact force is required. Therefore, the opening and closing electromagnet coils do not need to be energized for extended periods, only briefly for the instantaneous impact. When designing opening and closing coils, short-time withstand current is often used as a standard, typically several hundred milliseconds. If the coil is energized for more than 2 seconds, there is a risk of burnout.

[0003] Electromagnets are the first-stage control elements of circuit breaker operating mechanisms, including opening and closing electromagnets. The operation of these electromagnets has a significant impact on subsequent control and protection functions. However, during long-term operation, the iron core of the electromagnet may experience abnormal resistance during operation, thus affecting the opening and closing of the circuit breaker. Summary of the Invention

[0004] This application provides a method, device, and system for controlling the opening and closing electromagnets of a circuit breaker, which can monitor whether the resistance of the iron core is abnormal and can maximize the success rate of opening and closing.

[0005] In a first aspect, embodiments of this application provide a method for controlling the opening and closing electromagnet of a circuit breaker, including:

[0006] Within a preset period, the voltage data, current data, and core displacement data of the electromagnet during the opening and closing process of the circuit breaker are collected in real time.

[0007] The theoretical acceleration of the iron core at each moment within a preset period is determined based on the voltage data and the current data, and the actual acceleration of the iron core at each moment within a preset period is determined based on the displacement data.

[0008] Based on the actual acceleration and the theoretical acceleration at each moment, the excitation current of the electromagnet is adjusted, or the excitation current and the excitation time of the electromagnet are adjusted.

[0009] Secondly, embodiments of this application provide a circuit breaker opening and closing electromagnet control device, comprising:

[0010] The data acquisition module is used to collect voltage data, current data, and core displacement data of the electromagnet during the opening and closing process of the circuit breaker in real time within a preset period.

[0011] An acceleration determination module is used to determine the theoretical acceleration of the iron core based on the voltage data and the current data, and to determine the actual acceleration of the iron core based on the displacement data;

[0012] The adjustment module is used to adjust the excitation current of the electromagnet, or to adjust the excitation current and the excitation time of the electromagnet, based on the actual acceleration and theoretical acceleration within the preset period.

[0013] Thirdly, this application provides a circuit breaker opening and closing electromagnet control system, including an embedded electromagnet current closed-loop control system, wherein the embedded electromagnet current closed-loop control system includes the device provided in this application.

[0014] The circuit breaker opening and closing electromagnet control system also includes a drive signal synthesis system, an electromagnet, and an electromagnet drive circuit; the drive signal synthesis system includes an anti-jump logic operation circuit.

[0015] The technical solution provided in this application collects voltage data, current data, and core displacement data of the electromagnet during the opening and closing process of the circuit breaker within a preset period. The theoretical acceleration and actual acceleration at each moment within the preset period are determined by the collected data. The excitation current or the excitation time are adjusted by adjusting the theoretical acceleration and actual acceleration. This allows for monitoring whether the resistance of the core is abnormal, maximizing the success rate of opening and closing, and effectively preventing coil burnout. Attached Figure Description

[0016] Figure 1 This is a flowchart of a circuit breaker opening and closing electromagnet control method provided in an embodiment of this application;

[0017] Figure 2 This is a flowchart of a circuit breaker opening and closing electromagnet control program.

[0018] Figure 3 This is a structural block diagram of a circuit breaker opening and closing electromagnet control device provided in an embodiment of this application;

[0019] Figure 4 This is a schematic diagram of a circuit breaker opening and closing electromagnet control system.

[0020] Figure 5 This is a schematic diagram of the anti-jump logic operation circuit structure. Detailed Implementation

[0021] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Figure 1 This is a flowchart of a circuit breaker opening and closing electromagnet control method provided in an embodiment of this application. The method can be executed by a circuit breaker opening and closing electromagnet control device, which can be configured in an embedded electromagnet current closed-loop control system.

[0023] like Figure 1 As shown, the method provided in this application embodiment may include:

[0024] S110: Within a preset period, the voltage data, current data, and core displacement data of the electromagnet during the opening and closing process of the circuit breaker are collected in real time.

[0025] In this embodiment, the electromagnet includes a closing electromagnet and a opening electromagnet; in the opening state, the collected data includes voltage data, current data, and core displacement data of the opening electromagnet; in the closing state, the collected data includes voltage data, current data, and core displacement data of the closing electromagnet; the current data can be coil current data, and the voltage data can be coil voltage data.

[0026] S120: Based on the voltage data and the current data, determine the theoretical acceleration of the iron core at each moment within the preset period, and based on the displacement data, determine the actual acceleration of the iron core at each moment within the preset period.

[0027] In this embodiment, optionally, determining the theoretical acceleration of the iron core at various moments within a preset period based on the voltage and current data includes: determining the relationship between the partial derivative of the electromagnet's inductance with respect to displacement, the iron core acceleration, and the coil current, and using this relationship as a target relationship; constructing the voltage balance equation of the electromagnet; and solving the voltage balance equation using a fourth-order Runge-Kutta algorithm based on the voltage data, the current data, and the target relationship to obtain the theoretical acceleration at each moment. The derivation process of the theoretical acceleration is as follows:

[0028] The magnetic circuit of the electromagnet can be considered as a closed loop of "iron core + air gap". Since the permeability of the iron core is much greater than that of air, the magnetic reluctance of the iron core section can be ignored, and only the magnetic field strength H of the air gap section needs to be calculated. Taking the closed integration path as "along the iron core axis + through the air gap", since the direction of the magnetic field strength H in the air gap is consistent with the path direction, the integral can be simplified to:

[0029] (1);

[0030] in: It is the magnetic field strength in the air gap; It is the air gap length; N is the number of coil turns. This is the coil current, i.e., the magnetizing current.

[0031] From the magnetic induction intensity in the air gap Relationship with magnetic field strength H We can obtain:

[0032] (2);

[0033] in, is the vacuum permeability.

[0034] Then according to the magnetic flux formula and inductor With magnetic flux Magnetic flux relation From this, we can derive the expression for inductance as follows:

[0035] (3);

[0036] in, This represents the cross-sectional area of ​​the core at the air gap.

[0037] Magnetic field energy storage density in the air gap Magnetic field volume Therefore, the magnetic field in the air gap stores energy. for:

[0038] (4);

[0039] The relationship between the air gap length and the core displacement is as follows:

[0040] (5);

[0041] in, For Iron Heart's itinerary; This represents the displacement of the iron core.

[0042] Therefore, the electromagnetic attraction force is:

[0043] (6);

[0044] in, It is electromagnetic attraction.

[0045] Then Substituting equation (6) into equation (6) yields:

[0046] (7);

[0047] Similarly, taking the partial derivative of the inductance L with respect to x, we can obtain:

[0048] (8);

[0049] therefore, (9);

[0050] in, For the quality of the iron core, Equation (9) reflects the relationship between the core acceleration, the partial derivative of the inductance with respect to the displacement, and the coil current. It is the theoretical basis for the algorithm design of the dynamic adjustment judgment basis for the excitation parameters.

[0051] The voltage balance equation for an electromagnet is:

[0052] (10);

[0053] in, The coil voltage; t represents the coil resistance; t represents time.

[0054] The equation can be transformed into Among them, the derivative of inductance with respect to time... It is a bivariate function of t and L, denoted as The fourth-order Runge-Kutta algorithm was used to numerically solve it. The design starts at time [missing information]. Given Initial conditions at time 1 , =0, let the step size be h, the current time be t, h is equal to twice the sampling period, that is, a calculation is performed every two samples, and the calculation formula is as follows:

[0055] (11);

[0056] (12);

[0057] (13);

[0058] (14);

[0059] (15);

[0060] (16);

[0061] (17);

[0062] in, and They are respectively time, The coil current at any given moment; for The coil voltage at time t.

[0063] in, and They are respectively time, Inductance at any given moment.

[0064] in, , , and These are, respectively, the Euler displacement based on the starting slope, the Euler displacement predicted based on the midpoint slope, the Euler displacement predicted based on the improved midpoint slope, and the Euler displacement predicted based on the ending slope.

[0065] Therefore, any Moment Then calculate The speed of the iron core at any moment The derivative of the inductance with respect to displacement at any given time can then be obtained:

[0066] (18);

[0067] in, Let be the core displacement at time t; for The displacement of the iron core at any given moment; Let t be the core velocity at time t.

[0068] Then the acceleration can be calculated:

[0069] (19);

[0070] in, This represents the theoretical acceleration at time t.

[0071] In this embodiment, optionally, determining the actual acceleration of the iron core at each moment within a preset period based on the displacement data includes: using a second-order difference method to determine the actual acceleration at each moment based on the displacement data.

[0072] The actual acceleration at each moment is determined based on the displacement data at each moment and the sampling period.

[0073] Specifically, the actual acceleration at time t It can be obtained from the second-order difference of the displacement:

[0074] (20);

[0075] in, ;in, for The displacement of the iron core at any given moment.

[0076] S130: Based on the actual acceleration and the theoretical acceleration at each moment, adjust the excitation current of the electromagnet, or adjust the excitation current and the excitation time of the electromagnet.

[0077] In this embodiment, adjusting the excitation current of the electromagnet, or adjusting the excitation current and the excitation time of the electromagnet based on the actual acceleration and the theoretical acceleration at each moment, includes: determining the root mean square relative error of the theoretical acceleration and the actual acceleration within a preset period based on the actual acceleration and the theoretical acceleration at each moment; if the root mean square relative error is greater than a first preset threshold and less than a second preset threshold, increasing the reference current by one level to increase the excitation current; if the root mean square relative error is greater than the second preset threshold, increasing the reference current by one level and extending the excitation time by one preset period.

[0078] Specifically, the preset excitation time is KT (K is a positive integer; T is the excitation parameter adjustment period, i.e., the preset period). The core acceleration is analyzed once every preset period T (the calculation starts at least after the first period ends to avoid zero current). The excitation parameters are adjusted according to the results, such as increasing the reference current or extending the excitation time. The reference current and excitation time are adjustable in multiple levels, and the reference current and excitation time have upper limits.

[0079] Specifically, assuming there are k steps within each preset period T, the root mean square of the theoretical acceleration is calculated within each preset period T. and the root mean square of actual acceleration The root mean square relative error is .

[0080] Specifically, if the root mean square relative error is less than the first preset threshold, no adjustment is made; if the root mean square relative error is greater than the first preset threshold but less than the second preset threshold, the reference current is increased by one level to increase the excitation current; if the root mean square relative error is greater than the second preset threshold, the reference current is increased by one level and the excitation time is extended by one preset period. By dynamically adjusting the reference current and excitation time, the closing and opening of the circuit can be achieved to the greatest extent possible when the iron core movement is obstructed, which can effectively prevent the coil from burning out. The specific control program flow can be found in [reference needed]. Figure 2 .

[0081] like Figure 2 As shown, the control program flow includes: after the program starts, peripheral initialization is performed, including the initialization of timers, analog-to-digital converters (ADCs), pulse width modulation (PWM), and external interrupt event controllers. Then, a series of parameters are initialized, including five control parameters: preset reference current I0, maximum reference current I0+5ΔI, preset excitation time KT, maximum excitation time (K+5)T, and sampling period T0. Parameter initialization also includes four calculation parameters: calculation step size h, calculation start time t0=K0T (K0 is a constant less than K), inductor initial value condition L=0, and initial value condition dI / dt=0 for the derivative of coil current with respect to time. Then, the main program cyclically detects the closing flag; the closing flag is generated by an external interrupt subroutine, triggered by a low-level input pin of the external interrupt event controller. Upon detecting the closing flag, timing begins, and the upper limit of the hysteresis current I is generated. H and the lower limit of hysteresis current I LStart the timer, ADC, and PWM, and enter control mode. Before the initial moment of calculation (i.e., time t is less than or equal to t0), only execute the current hysteresis control subroutine to perform current hysteresis control cyclically; specifically, when the coil current is greater than the upper limit of the hysteresis current, change the PWM duty cycle to 0%, and when the coil current is less than the lower limit of the hysteresis current, change the PWM duty cycle to 100%. After the time exceeds the initial calculation time t0, in each sampling cycle, the core motion parameter calculation subroutine is executed to perform a core motion parameter calculation, and the current hysteresis control subroutine is executed to perform current hysteresis control. Furthermore, in each preset cycle T, the excitation parameter dynamic adjustment subroutine is executed to adjust the excitation parameters. Specifically, the core motion parameter calculation subroutine is the method provided in this embodiment for calculating theoretical and actual acceleration. When time t increases by a step size h, the next cycle is executed. The excitation parameter dynamic adjustment subroutine is specifically used to adjust the excitation parameters based on the root mean square relative error. For example, if the root mean square relative error is greater than a first preset threshold and less than a second preset threshold, the reference current is increased. If the root mean square relative error is greater than the second preset threshold, the reference current will be increased. Furthermore, the excitation time is extended by a preset period T, where, This is the increased value of the reference current. After excitation, the timer, PWM, and ADC are turned off, the closing flag is cleared, and finally the initialization data is restored. This restoration includes re-initializing the preset values ​​of the reference current, excitation time, and initial calculation conditions.

[0082] The technical solution provided in this application collects voltage data, current data, and core displacement data of the electromagnet during the opening and closing process of the circuit breaker within a preset period. The theoretical acceleration and actual acceleration at each moment within the preset period are determined by the collected data. The excitation current or the excitation time are adjusted by adjusting the theoretical acceleration and actual acceleration. This allows for monitoring whether the resistance of the core is abnormal, maximizing the success rate of opening and closing, and effectively preventing coil burnout.

[0083] Figure 3 This is a structural block diagram of a circuit breaker opening and closing electromagnet control device provided in an embodiment of this application, as shown below. Figure 3 As shown, the device may include:

[0084] The data acquisition module 310 is used to acquire voltage data, current data and core displacement data of the electromagnet during the opening and closing process of the circuit breaker in real time within a preset period.

[0085] The acceleration determination module 320 is used to determine the theoretical acceleration of the iron core based on the voltage data and the current data, and to determine the actual acceleration of the iron core based on the displacement data.

[0086] The adjustment module 330 is used to adjust the reference current to adjust the excitation current of the electromagnet based on the actual acceleration and theoretical acceleration within the preset period, or to adjust the reference current and excitation time.

[0087] In an optional embodiment, adjusting the excitation current of the electromagnet, or adjusting the excitation current and the excitation time of the electromagnet based on the actual acceleration and the theoretical acceleration at various times, includes:

[0088] Based on the actual acceleration and the theoretical acceleration at each moment, the root mean square relative error of the theoretical acceleration and the actual acceleration within a preset period is determined;

[0089] If the root mean square relative error is greater than the first preset threshold and less than the second preset threshold, the reference current will be increased by one level to increase the excitation current.

[0090] If the root mean square relative error is greater than the second preset threshold, the reference current is increased by one level and the excitation time is extended by one preset period.

[0091] In an optional embodiment, determining the theoretical acceleration of the iron core at various moments within a preset period based on the voltage data and the current data includes:

[0092] Determine the relationship between the partial derivative of the inductance with respect to the core displacement, the core acceleration and the coil current, and use this relationship as the target relationship;

[0093] Construct the voltage balance equation for the electromagnet;

[0094] The fourth-order Runge-Kutta algorithm is used to solve the voltage balance equation based on the voltage data, the current data, and the target relationship to obtain the theoretical acceleration at each moment.

[0095] In an optional embodiment, determining the actual acceleration of the iron core at various moments within a preset period based on the displacement data includes:

[0096] The actual acceleration at each moment is determined based on the displacement data using a second-order difference method.

[0097] In one alternative embodiment, the actual acceleration at each moment is determined based on the displacement data at each moment and the sampling period.

[0098] In related technologies, after a circuit breaker completes a closing operation, an abnormality in the control circuit may lead to repeated periodic malfunctions of "opening-closing," a phenomenon known as "trip fault." The typical characteristics of a trip fault are that the circuit breaker immediately opens after closing, closes again after a short interval, and repeats this cycle, accompanied by high-frequency heating of the opening and closing coils, severe vibration of the mechanical mechanism, and frequent switching of the contact system. The essence of a trip fault is a vicious cycle of continuous closing command input and opening triggering. Trip faults are one of the most serious faults of circuit breakers, capable of damaging the circuit breaker and expanding the fault range, posing a significant threat to the safe and stable operation of the distribution network. To address circuit breaker trip faults, related technologies mainly employ adding an anti-trip protection circuit to the operating circuit. This increases the complexity of the circuit breaker's secondary circuit, raises design costs, and introduces other uncertainties.

[0099] Figure 4 This is a schematic diagram of a circuit breaker opening and closing electromagnet control system provided in an embodiment of this application, as shown below. Figure 4 As shown, it includes an embedded electromagnet current closed-loop control system, which includes the circuit breaker opening and closing electromagnet control system device provided in the embodiments of this application ( Figure 4 (not shown). The circuit breaker opening and closing electromagnet control system also includes a drive signal synthesis system, an electromagnet, and an electromagnet drive circuit; the drive signal synthesis system includes an anti-jump logic operation circuit.

[0100] The electromagnets include a tripping electromagnet and a closing electromagnet, each using the same driving circuit. The main body of each driving circuit consists of electromagnet coils Coil1 and Coil2, electronic switches M1 and M2, and sampling resistors R1 and R2 connected in series. D1 and D2 are fast recovery freewheeling diodes. The S1 and S2 driving signals are output from the driving signal synthesis system and are used to turn the electronic switches M1 and M2 on and off, respectively. The voltage across the sampling resistors R1 and R2 is proportional to the coil current. Feeding the voltage values ​​of the sampling resistors R1 and R2 back to the embedded electromagnet current closed-loop control system completes the sampling of the coil current. Voltage division of the driving voltage using resistors achieves the control of the coil driving voltage u. coil The sampling can be performed using a displacement sensor to sample the core displacement x1 of the closing electromagnet and the core displacement x2 of the opening electromagnet; where S1 is the closing drive signal and S2 is the opening drive signal.

[0101] The drive signal synthesis system may include an anti-skip logic circuit, an external opening / closing signal interface, and an opening / closing status monitoring interface. This system can process the closing status signal A0, closing signal A1, opening signal A2, skip fault signal A3, and the original drive signal S0, outputting drive signals S1 and S2. The embedded electromagnet current closed-loop control system processes the sampled current signal, generates the original drive signal S0 and the skip fault signal A3, and can also connect to an external human-machine interface and communication interface, enabling monitoring and setting of operating parameters and remote monitoring.

[0102] The closed-loop control principle of the opening and closing coil current is as follows: After rectification and filtering, the AC / DC power input obtains a stable DC voltage, which is applied to the two ends of the closing electromagnet drive circuit or the opening electromagnet. Through the rapid action of electronic switch M1 or M2, a high-frequency square wave voltage can be obtained across the coil. When electronic switch M1 or M2 is turned on, the rectified and filtered positive voltage is applied to the coil. Due to the hysteresis effect of the coil inductance, the coil current rises rapidly. When electronic switch M1 or M2 is turned off, the coil current decreases through the freewheeling diode D1 or D2. By controlling the duty cycle of electronic switch M1 or M2, the required coil current can be obtained. When electronic switch M1 or M2 is turned on, the coil current i can be sampled through the terminal voltage of sampling resistor R1 or R2. coil1 or i coil2 , the coil current i coil1 Or i coil2 Respectively with reference current i ref By comparison, the error signal i can be obtained. e And based on the error signal i e The original drive signal S0 is generated. The original drive signal S0 is processed by the drive signal synthesis system to synthesize the drive signal S1 and the drive signal S2. The synthesized drive signal drives the electronic switch tube M1 or M2 through the drive circuit to adjust the duty cycle of the coil voltage, so as to realize the closed-loop control of the opening and closing coil current.

[0103] The anti-skip logic circuit is used to generate a closing drive signal based on the original drive signal and closing conditions to control the circuit breaker to close when the circuit breaker is in the open state; or, the anti-skip logic circuit is used to generate a opening drive signal based on the original drive signal and opening conditions to control the circuit breaker to open when the circuit breaker is in the closed state; wherein the closing conditions include the circuit breaker being in the open state, the presence of a closing signal, and the absence of a fault signal; the opening conditions include the circuit breaker being in the closed state and the presence of an opening signal.

[0104] Specifically, the essence of a circuit breaker tripping fault is caused by the simultaneous occurrence of a tripping signal and a continuous closing signal. Therefore, an anti-tripping logic circuit is needed to process the input closing and tripping signals. Performing a closing operation requires three conditions: the circuit breaker is in the tripping state, a closing signal is present, and there is no tripping fault signal. Performing a tripping operation requires two conditions: the circuit breaker is in the closing state and a tripping signal is present. The S1 drive signal is synthesized from the closing condition and the original drive signal S0, and the S2 drive signal is synthesized from the tripping condition and the original drive signal S0. Anti-tripping aims to prevent reverse tripping; therefore, the generation of the tripping fault signal is based on the condition of being in the closing state and having a closing signal. On this basis, if there is currently no tripping fault signal and there is a tripping signal, then a tripping fault signal is generated; if there is currently a tripping fault signal, then the tripping fault signal is maintained.

[0105] The logical expression of the anti-jump logic operation circuit is:

[0106] (twenty one);

[0107] in, This indicates the closing drive signal; This indicates the tripping drive signal; Indicates the original drive signal; Indicates the closing signal; Indicates the trip signal; A logic signal indicating that the closing status signal is true; This indicates that the closing status signal is false. The jump fault signal is false. This indicates a jump fault signal; The signal indicating the next jump fault can be obtained from the logic expression in (21) above. The structure of the anti-jump logic operation circuit can be found in the diagram. Figure 5 As shown.

[0108] like Figure 5 As shown, the anti-jump logic operation circuit includes a first NOT gate logic circuit F1, a second NOT gate logic circuit F2, a third NOT gate logic circuit F3, a fourth NOT gate logic circuit F4, a first AND gate logic circuit Y1, a second AND gate logic circuit Y2, a third AND gate logic circuit Y3, a fourth AND gate logic circuit Y4, a fifth AND gate logic circuit Y5, a sixth AND gate logic circuit Y6, and an OR gate logic circuit H1.

[0109] The first input terminal of the first AND gate logic circuit Y1 receives the original driving signal. The second input terminal of the first AND gate logic circuit Y1 is connected to the output terminal of the second AND gate logic circuit Y2. The output terminal of the first AND gate logic circuit Y1 outputs the closing drive signal, namely the S1 drive signal.

[0110] The first input terminal of the second AND gate logic circuit Y2 is connected to the output terminal of the first NOT gate logic circuit F1, and the second input terminal of the second AND gate logic circuit Y2 receives the closing signal. The third input of the second AND gate Y2 is connected to the output of the second NOT gate F2; the input of the second NOT gate F2 is a logic signal indicating that the closing signal is true. ;

[0111] The input terminal of the first NOT gate logic circuit F1 receives a jump fault signal. The output of the first NOT gate logic circuit F1 is connected to the first input of the third AND gate logic circuit Y3; the second input of the third AND gate logic circuit Y3 receives the trip signal. The third input terminal of the third AND gate logic circuit Y3 receives the closing signal. The output of the third AND gate Y3 is connected to the first input of the OR gate H1, and the output of the OR gate H1 outputs a jump fault signal. .

[0112] The second input of the OR gate logic circuit H1 is connected to the output of the fourth AND gate logic circuit Y4; the first input of the fourth AND gate logic circuit Y4 receives the closing signal. The second input terminal of the fourth AND gate logic circuit Y4 receives a jump fault signal. The original drive signal is input to the first input terminal of the fifth AND gate logic circuit Y5. The output of the fifth AND gate Y5 outputs a tripping drive signal, i.e. The driving signal is connected to the second input of the fifth AND gate logic circuit Y5 and the output of the sixth AND gate logic circuit Y6.

[0113] The first input terminal of the sixth AND gate logic circuit Y6 receives the trip signal. The second input terminal of the sixth AND gate logic circuit Y6 is a logic signal indicating that the gate is closed and the state signal is true. The input terminal of the third NOT gate logic circuit F3 receives the closing signal. The closing signal The processed signal is output from the output terminal of the third NOT gate logic circuit F3; the input terminal of the fourth NOT gate logic circuit F4 receives the trip signal. The trip signal After processing, the output is sent through the output terminal of the fourth NOT gate logic circuit F4.

[0114] This application embodiment uses an anti-jump logic operation circuit composed of logic gate circuits as an anti-jump protection circuit. The signal is processed directly by the logic circuit, and the processing speed can reach the nanosecond level. The circuit structure is simple, small in size and low in cost.

[0115] The above embodiments are merely illustrative examples and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this application.

Claims

1. A circuit breaker opening and closing electromagnet control method characterized by, The method comprises the following steps: acquiring, in real time, voltage data, current data and displacement data of a core of the electromagnet during the opening and closing process of the circuit breaker in a preset period; determining theoretical acceleration of the core at each moment in the preset period based on the voltage data and the current data, and determining actual acceleration of the core at each moment in the preset period based on the displacement data; adjusting the exciting current of the electromagnet or adjusting the exciting current and the exciting time of the electromagnet based on the actual acceleration and the theoretical acceleration at each moment; wherein the determination of the theoretical acceleration of the core at each moment in the preset period based on the voltage data and the current data comprises: determining a relationship between a partial derivative of inductance to core displacement, core acceleration and coil current as a target relationship; constructing a voltage balance equation of the electromagnet; solving the voltage balance equation based on the voltage data, the current data and the target relationship by using a fourth-order Runge-Kutta algorithm to obtain the theoretical acceleration at each moment.

2. The method of claim 1, wherein, The adjustment of the exciting current of the electromagnet or the adjustment of the exciting current and the exciting time of the electromagnet based on the actual acceleration and the theoretical acceleration at each moment comprises: determining a root-mean-square relative error of the theoretical acceleration and the actual acceleration in the preset period based on the actual acceleration and the theoretical acceleration at each moment; if the root-mean-square relative error is greater than a first preset threshold and less than a second preset threshold, increasing a reference current by one notch to increase the exciting current; if the root-mean-square relative error is greater than the second preset threshold, increasing the reference current by one notch and prolonging the exciting time by a preset period.

3. The method of claim 1, wherein, The determination of the actual acceleration of the core at each moment in the preset period based on the displacement data comprises: determining the actual acceleration at each moment based on the displacement data by using a second-order difference method.

4. The method according to claim 3, wherein the actual acceleration at each moment is determined based on the displacement data at each moment and a sampling period. The method comprises the following steps:

5. A circuit breaker opening and closing electromagnet control device characterized by comprising: acquiring, in real time, voltage data, current data and displacement data of a core of the electromagnet during the opening and closing process of the circuit breaker in a preset period; determining theoretical acceleration of the core at each moment in the preset period based on the voltage data and the current data, and determining actual acceleration of the core at each moment in the preset period based on the displacement data; adjusting the exciting current of the electromagnet or adjusting the exciting current and the exciting time of the electromagnet based on the actual acceleration and the theoretical acceleration at each moment; wherein the determination of the theoretical acceleration of the core at each moment in the preset period based on the voltage data and the current data comprises: determining a relationship between a partial derivative of inductance to core displacement, core acceleration and coil current as a target relationship; constructing a voltage balance equation of the electromagnet; solving the voltage balance equation based on the voltage data, the current data and the target relationship by using a fourth-order Runge-Kutta algorithm to obtain the theoretical acceleration at each moment. Solve the voltage balance equation based on the voltage data, the current data and the target relationship by using a fourth-order Runge-Kutta algorithm to obtain a theoretical acceleration at each time.

6. A circuit breaker opening and closing electromagnet control system comprising an embedded electromagnet current closed-loop control system, the embedded electromagnet current closed-loop control system comprising the device of claim 5. The circuit breaker opening and closing electromagnet control system further comprises a drive signal synthesis system, an electromagnet and an electromagnet drive circuit; the drive signal synthesis system comprises an anti-jump logic operation circuit.

7. The system of claim 6, wherein, the anti-jump logic operation circuit is configured to generate a closing drive signal based on an original drive signal and a closing condition to control the circuit breaker to close in the circuit breaker opening state; or the anti-jump logic operation circuit is configured to generate an opening drive signal based on the original drive signal and an opening condition to control the circuit breaker to open in the circuit breaker closing state; the closing condition comprises that the circuit breaker is in the opening state, there is a closing signal and there is no jump fault signal; the opening condition comprises that the circuit breaker is in the closing state and there is an opening signal. The logic expression of the anti-jump logic operation circuit is:

8. The system of claim 7, wherein, The anti-jump logic operation circuit comprises a first NOT gate logic circuit, a second NOT gate logic circuit, a third NOT gate logic circuit, a fourth NOT gate logic circuit, a first AND gate logic circuit, a second AND gate logic circuit, a third AND gate logic circuit, a fourth AND gate logic circuit, a fifth AND gate logic circuit, a sixth AND gate logic circuit and an OR gate logic circuit; ； wherein denotes the closing drive signal; denotes the opening drive signal; denotes the original drive signal; denotes the closing signal; denotes the opening signal; denotes a logic signal that the closing status signal is true; denotes that the closing status signal is false; is false for a jump fault signal, denotes the jump fault signal; denotes the next jump fault signal.

9. The system of claim 7, wherein, the first input end of the first AND gate logic circuit inputs an original drive signal, the second input end of the first AND gate logic circuit is connected to the output end of the second AND gate logic circuit, and the output end of the first AND gate logic circuit outputs a closing drive signal; the first input end of the second AND gate logic circuit is connected to the output end of the first NOT gate logic circuit, the second input end of the second AND gate logic circuit inputs a closing signal, the third input end of the second AND gate logic circuit is connected to the output end of the second NOT gate logic circuit, and the input end of the second NOT gate logic circuit inputs a logic signal whose closing signal is true; the input end of the first NOT gate logic circuit inputs a jump fault signal, the output end of the first NOT gate logic circuit is connected to the first input end of the third AND gate logic circuit, the second input end of the third AND gate logic circuit inputs an opening signal, the third input end of the third AND gate logic circuit inputs a closing signal, the output end of the third AND gate logic circuit is connected to the first input end of the OR gate logic circuit, and the output end of the OR gate logic circuit outputs a jump fault signal; the second input end of the OR gate logic circuit is connected to the output end of the fourth AND gate logic circuit, the first input end of the fourth AND gate logic circuit inputs a closing signal, and the second input end of the fourth AND gate logic circuit inputs the jump fault signal. ​ The first input end of the fifth AND gate logic circuit inputs the original driving signal, the output end of the fifth AND gate logic circuit outputs a tripping driving signal, and the second input end of the fifth AND gate logic circuit is connected to the output end of the sixth AND gate logic circuit; The first input end of the sixth AND gate logic circuit inputs a tripping signal, and the second input end of the sixth AND gate logic circuit inputs a logic signal that is true when the closing state signal is true; The input end of the third NOT gate logic circuit inputs the closing signal, and the output end of the third NOT gate logic circuit outputs the closing signal after processing; The input end of the fourth NOT gate logic circuit inputs the tripping signal, and the output end of the fourth NOT gate logic circuit outputs the tripping signal after processing.

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