Motor parameter inversion method and related device based on circuit breaker vector control system

Abstract

The present application relates to a motor parameter inversion method and related device based on a circuit breaker vector control system. The method includes: configuring the inversion operating parameters of the circuit breaker motor operating mechanism so that the motor operating mechanism is relatively stationary during the inversion process; generating a control signal according to the inversion operating parameters, and controlling the motor operating mechanism to be in a voltage dynamic equal state based on the control signal; collecting the bus voltage in the voltage dynamic equal state, and determining the actual voltage of each winding based on the bus voltage and the control signal; collecting the actual current of the three-phase winding, fitting the current curve of the motor operating mechanism during the inversion process according to the actual current, and determining the curve parameters of the current curve; constructing a functional relationship model including the motor inversion parameters, and obtaining the motor inversion parameters of the corresponding phase winding based on each set of curve parameters and each winding. Compared with the prior art, the present application does not require the addition of additional structures and circuits, is simple to operate, has high reliability, and has high accuracy in inversion results.

Description

Technical Field

[0001] The present application relates to the technical field of high-voltage circuit breakers, and in particular to a motor parameter inversion method and related devices based on a circuit breaker vector control system. Background Art

[0002] As a crucial component of power systems, circuit breakers play a crucial role in controlling and protecting the power grid. When excessive current flows through the grid, circuit breakers can quickly trip the circuit breaker, ensuring power system safety and minimizing financial losses. Therefore, circuit breaker reliability plays a crucial role in the safe operation of the power grid. Traditional operating mechanisms can be categorized by energy source, including electromagnetic, spring, pneumatic, and hydraulic types. In high-voltage circuit breaker applications, due to the large number of mechanical parts and complex structure of traditional operating mechanisms, reliability requirements for each component are increased. Furthermore, since hydraulic operating mechanisms utilize liquids and other materials to transfer energy, their response speed may be slower than expected and they may also experience transmission medium leakage. Traditional operating mechanisms, comprised of multiple connecting rods and latches, exhibit numerous links, large cumulative motion tolerances, slow response, poor controllability, and low efficiency. Furthermore, these operating mechanisms lack the ability to adjust and control the operating process. Consequently, high-voltage circuit breakers cannot achieve maximum performance with these types of operating mechanisms. Statistics show that many circuit breaker failures are caused by operating mechanism failure.

[0003] In recent years, with the advancement of digital control technology and the improvement in the performance of power electronic devices, rotating motor operating mechanisms using closed-loop control have gradually become a focus of research and application. These motor operating mechanisms coordinate the movement of a motor and connecting rod to drive the circuit breaker's opening and closing operations. By integrating modern power electronics and advanced control theory, these mechanisms can dynamically control the movement of the moving contact, ensuring ideal opening and closing motion. This provides high reliability and controllability, significantly improving circuit breaker performance. Compared to traditional circuit breaker operating mechanisms, these motor operating mechanisms utilize the rotation of the motor's main shaft to drive the circuit breaker contacts, thereby opening and closing the circuit breaker. These mechanisms offer a simpler transmission mechanism, enhanced controllability, greater reliability, and longer mechanical life. Research on motor resistance and inductance inversion methods for motor operating mechanisms facilitates timely fault detection and further improves operating mechanism reliability.

[0004] Existing inversion methods typically include direct measurement and AI-based inversion. Direct measurement requires additional equipment and operations during motor operation, and measurement accuracy is limited by the precision of the measuring equipment and the stability of the motor's operating state. AI-based inversion, on the other hand, relies on a large amount of training data to train the model. The quality and quantity of the data significantly impact the model's accuracy. Furthermore, if the training data is incomplete or underrepresented, the model's generalization ability will be significantly limited, resulting in reduced accuracy in the inversion results. Summary of the Invention

[0005] Based on this, it is necessary to provide a motor parameter inversion method and related device based on the circuit breaker vector control system, which is implemented based on the original vector control system of the circuit breaker and has high accuracy of inversion results, in order to solve the above technical problems.

[0006] In a first aspect, the present application provides a motor parameter inversion method based on a circuit breaker vector control system, the method comprising:

[0007] configuring inversion operating parameters of the circuit breaker motor operating mechanism so that the motor operating mechanism remains relatively stationary during the inversion process; the inversion operating parameters include an inversion current of the motor operating mechanism during the inversion process and an expected voltage of each phase winding and its polarity; the expected voltage of one phase winding of the three-phase winding of the motor operating mechanism is zero, while the expected voltages of the remaining two phase windings are determined based on the inversion current;

[0008] generating a control signal according to the inversion operation parameter, and controlling the motor operating mechanism to be in a voltage dynamic equalization state based on the control signal;

[0009] collecting the bus voltage in the voltage dynamic equal state, and determining the actual voltage of each winding according to the bus voltage and the control signal;

[0010] collecting actual currents of the three-phase windings, fitting a current curve of the motor operating mechanism during the inversion process according to the actual currents, and determining curve parameters of the current curve;

[0011] Returning to the step of configuring the inversion operating parameters of the circuit breaker motor operating mechanism, respectively configuring the desired voltage of one of the two non-zero phase windings to be zero and determining the desired voltages of the other two phase windings based on the inversion current, until multiple sets of current curves and their corresponding curve parameters are obtained;

[0012] A functional relationship model including motor inversion parameters is constructed, and the functional relationship model is solved based on each set of curve parameters and the actual voltage corresponding to each winding to obtain the motor inversion parameters of the corresponding phase winding.

[0013] In a second aspect, the present application further provides a motor parameter inversion device based on a circuit breaker vector control system, the device comprising:

[0014] a parameter configuration module, configured to configure inversion operating parameters of the circuit breaker motor operating mechanism in response to a configuration signal, so that the motor operating mechanism remains relatively stationary during an inversion process; the inversion operating parameters include an inversion current of the motor operating mechanism during the inversion process and an expected voltage of each phase winding and its polarity; the expected voltage of one phase winding of the three-phase winding of the motor operating mechanism is zero, while the expected voltages of the remaining two phase windings are determined based on the inversion current;

[0015] a control signal generating module, configured to generate a control signal according to the inversion operation parameter, and control the motor operating mechanism to be in a voltage dynamic equalization state based on the control signal;

[0016] a voltage acquisition and calculation module, configured to acquire the bus voltage when the voltage is dynamically equal, and determine the actual voltage of each winding according to the bus voltage and the control signal;

[0017] a curve generating module, configured to collect actual currents of the three-phase windings, fit a current curve of the motor operating mechanism during an inversion process according to the actual currents, and determine curve parameters of the current curve;

[0018] An execution loop module is used to determine whether the number of current curves and their curve parameters meets the preset conditions, and if so, generates an end signal; otherwise, generates the configuration signal and jumps to the parameter configuration module until multiple sets of current curves and their corresponding curve parameters are obtained;

[0019] A parameter calculation module is used to construct a functional relationship model including motor inversion parameters in response to the end signal, and solve the functional relationship model based on each group of curve parameters and the actual voltage corresponding to each winding to obtain the motor inversion parameters of the corresponding phase winding.

[0020] In a third aspect, the present application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and wherein the processor implements the steps of the above-described method when executing the computer program.

[0021] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps of the method described above when executed by a processor.

[0022] In the above-mentioned motor parameter inversion method based on the circuit breaker vector control system, according to the mechanical structure of the circuit breaker operating mechanism, by configuring the inversion operating parameters of the circuit breaker motor operating mechanism, combined with the spring reaction force when closing the motor operating mechanism and the self-closing force characteristics when opening the motor operating mechanism, the motor operating mechanism is made relatively static during the inversion process to prevent the faulty motor from causing damage to the power system; then, according to the inversion operating parameters, a control signal is generated to control the motor operating mechanism to be in a voltage dynamic equal state, and then the bus voltage is collected, and the actual voltage of each winding is determined according to the bus voltage and the control signal, and the three-phase winding voltage is collected. The actual current is fitted according to the actual current to the current curve of the motor operating mechanism during the inversion process, and the curve parameters of the current curve are determined; finally, a functional relationship model including the motor inversion parameters is constructed, and the functional relationship model is solved based on each set of curve parameters and the actual voltage corresponding to each winding to obtain the motor inversion parameters of the corresponding phase winding; the entire process is based on the original vector control system of the operating mechanism and adopts an open-loop PWM control method. There is no need to add additional structures and circuits. The operation is simple and the reliability is high. In addition, based on the solution of the curve parameters, the accuracy of the resistance and inductance inversion of the final motor is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present application or related technical descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 1 is a flow chart of a motor parameter inversion method based on a circuit breaker vector control system in one embodiment;

[0025] Figure 2 Schematic diagram of the process of step S101 in one embodiment;

[0026] Figure 3 Schematic diagram of the process of step S102 in one embodiment;

[0027] Figure 4 Schematic diagram of the process of step S104 in one embodiment;

[0028] Figure 5 Schematic diagram of the process of step S106 in one embodiment;

[0029] Figure 6 FIG1 is a hardware structure diagram of a circuit breaker motor operating mechanism in one embodiment;

[0030] Figure 7 A control principle diagram of a circuit breaker vector control system in one embodiment;

[0031] Figure 8 1 is a schematic diagram of the principle of a motor parameter inversion method based on a circuit breaker vector control system in one embodiment;

[0032] Figure 9 Schematic diagram of the current flow direction of the stator winding of a motor during one acquisition cycle in one embodiment;

[0033] Figure 10 is a current waveform diagram of a motor stator winding in one embodiment;

[0034] Figure 11 is a current waveform diagram of a first-order circuit composed of an inverting resistor and an inverting inductor in one embodiment;

[0035] Figure 12 1 is a structural block diagram of a motor parameter inversion device based on a circuit breaker vector control system in one embodiment. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0037] In one embodiment, Figure 1 As shown, a motor parameter inversion method based on a circuit breaker vector control system is provided. This embodiment uses the application of this method to a terminal as an example to illustrate. It is understandable that this method can also be applied to a server, and can also be applied to a system including a terminal and a server, and is implemented through the interaction between the terminal and the server. In this embodiment, the motor parameters that need to be inverted (hereinafter referred to as "motor inversion parameters") mainly include the resistance and inductance of the motor operating mechanism (hereinafter also referred to as "motor" or "operating mechanism"). By inverting and calculating the inductance and resistance of the motor, the values ​​and changes of the resistance and inductance can be grasped in time, which is conducive to timely detection of motor faults, thereby improving the reliability of the motor operating mechanism. Specifically, the method of this embodiment includes the following steps S101 to S106. Among them:

[0038] Step S101 : configuring inversion operating parameters of the circuit breaker motor operating mechanism so that the motor operating mechanism remains relatively stationary during the inversion process.

[0039] Among them, the circuit breaker motor operating mechanism is used to operate the high-voltage circuit breaker, enabling the high-voltage circuit breaker to achieve closing and opening operations to ensure the stable and safe operation of the circuit; and the internal characteristic inversion of the circuit breaker motor operating mechanism can calculate various characteristic parameters inside the motor to obtain the accurate values ​​or change patterns of these parameters, thereby providing strong support for the design, optimization and fault diagnosis of the circuit breaker.

[0040] The inversion operating parameters refer to the operating parameters of the circuit breaker motor operating mechanism during the inversion process. By configuring the inversion operating parameters, the motor operating mechanism can be kept relatively stationary during the inversion process, thereby preventing further damage to the operating mechanism caused by a faulty motor. Based on the motor inversion parameters to be inverted in this embodiment, the inversion operating parameters include, but are not limited to, the inversion current of the motor during the inversion process and the expected voltage and polarity of each phase winding (three-phase stator winding). It is understood that in other embodiments, depending on the motor inversion parameters, the inversion operating parameters may also include electromotive force, electric power, operating time, etc.

[0041] Among them, the inversion current refers to the operating current of the motor during the inversion process, which is used to determine the size of the expected voltage of each phase winding; the expected voltage of each phase winding refers to the expected voltage of each winding on the three-phase winding of the motor during the inversion process, which is used to adjust the electromagnetic torque of the motor; the polarity of the expected voltage refers to the positive and negative direction of the voltage on each winding, which is used to determine the direction of current flow to control the operating mechanism to remain stationary during the inversion process.

[0042] Among them, the relative stillness of the motor operating mechanism means that the direction of rotation of the motor operating mechanism is the direction of the limit block of the motor operating mechanism. The limit block of the motor operating mechanism is set based on the self-maintenance requirements of the mechanism to achieve the opening position and to reduce the impact of the mechanism overshoot on the arc extinguishing chamber, so that the operating mechanism cannot continue to move after reaching the closing and opening positions, so as to limit the movement range of the motor operating mechanism, prevent it from exceeding the set safety range, and extend the service life of the arc extinguishing chamber. By setting the size of the inversion current, a suitable expected voltage can be obtained, and then the electromagnetic torque of the motor is adjusted according to the expected voltage. When the two are equal and in opposite directions, when the motor operating mechanism moves and contacts the limit block, the limit block will generate a reaction force to prevent the further movement of the motor, so that the electromagnetic torque of the motor and the reaction force generated by the limit block reach a balance state. The two forces will offset each other, thereby achieving static stability of the motor operating mechanism.

[0043] Specifically, the inversion current of the circuit breaker motor operating mechanism during the inversion process, as well as the expected voltage and polarity of each phase winding, are configured based on the operating characteristics of the motor operating mechanism, so that the rotation direction of the motor operating mechanism is in the direction of the motor operating mechanism's limit block, ensuring that the motor operating mechanism remains stationary during the inversion process. When configuring the expected voltage and polarity, the expected voltage of one of the three-phase windings of the motor is set to zero, while the expected voltages of the remaining two phase windings are determined based on the inversion current. For example, the expected voltage of phase A is configured to be zero, while the expected voltages of phases B and C are determined based on the inversion current. The polarities of the expected voltages of phases B and C are configured so that the rotation direction of the motor operating mechanism is in the direction of the motor operating mechanism's limit block. During this process, no current flows through phase A, so that the corresponding parameter relationship between phases B and C can be determined in subsequent processing and analysis.

[0044] Step S102 : generating a control signal according to the inversion operation parameter, and controlling the circuit breaker motor operating mechanism to be in a voltage dynamic equalization state based on the control signal.

[0045] Among them, the control signal is a PWM control signal, which is used to control the winding action of the motor operating mechanism. The PWM control signal carries information such as the comparison value and duty cycle of the PWM control signal to control and adjust the operation of the motor operating mechanism.

[0046] The dynamic voltage equality state is defined as the equivalent voltage of each phase winding of the circuit breaker motor operating mechanism being equal to the desired voltage of the corresponding phase under the dynamic control of the control signal. The equivalent voltage of each phase winding refers to the average voltage across the equivalent winding of the motor operating mechanism. The equivalent winding of the motor operating mechanism refers to the motor winding controlled by the PWM control signal, and the magnetic field generated by the equivalent winding corresponds to the desired magnetic field. In this way, the equivalent voltage of the motor operating mechanism can be dynamically equalized to the desired voltage by dynamically adjusting the control signal, thereby ensuring the accurate collection and analysis of the operating parameters of the motor operating mechanism during the inversion process.

[0047] Specifically, based on the desired voltage of each phase determined in step S101 (i.e., the voltage of each phase of the three-phase winding), a PWM control signal for each phase is generated based on the control system of the circuit breaker motor operating mechanism, and the motor operating mechanism is controlled according to the PWM control signal, so that the equivalent voltage of each phase winding of the circuit breaker motor operating mechanism is equal to the desired voltage of the corresponding phase under the dynamic control of the PWM control signal.

[0048] Step S103 : collecting the bus voltage under the voltage dynamic equalization state, and determining the actual voltage of each winding according to the bus voltage and the control signal.

[0049] The bus voltage refers to the voltage at the input of the inverter (see the description of the "inverter module" below) in the structure of the circuit breaker operating mechanism. It is also the basic voltage used for modulation during the PWM control process and is used to determine the actual voltage of each winding.

[0050] The actual voltage of each winding refers to the voltage actually applied to each winding when the motor operating mechanism operates under the control of the PWM control signal (that is, during the inversion process).

[0051] Specifically, when the equivalent voltage of each phase winding equals the desired voltage of the corresponding phase under the dynamic control of the PWM control signal, the bus voltage of the motor operating mechanism is collected to obtain the bus voltage. Based on the bus voltage and the duty cycle carried in the PWM control signal corresponding to each phase winding, the actual voltage of each phase winding is determined and temporarily stored for subsequent analysis and processing. In specific implementation, the bus voltage can be measured using a voltage sensor, multimeter, or other device.

[0052] Step S104 , collecting the actual current of the three-phase winding, fitting the current curve in the motor inversion process according to the actual current, and determining the curve parameters of the current curve.

[0053] The actual current of the three-phase winding refers to the current actually flowing through each phase winding when the motor operating mechanism operates under the control of the PWM control signal (that is, during the inversion process).

[0054] The current curve is a time-varying curve obtained by fitting the actual current in each phase winding. The corresponding curve parameters can be obtained by fitting and solving the current curve. The current parameters include the steady-state current value and the time constant at which the current curve stabilizes at a certain moment.

[0055] Specifically, the actual current of the three-phase winding is collected, and the current curve of the motor during the inversion process is fitted based on the actual current of each phase. By solving the current curve, the corresponding steady-state current value and time constant are obtained. In specific implementation, the actual current of the three-phase winding can be measured using a current sensor, multimeter, or other device. When fitting and solving the current curve, one or more methods including but not limited to interpolation, least squares method, polynomial fitting, and maximum likelihood estimation can be used.

[0056] Step S105, returning to the step of configuring the inverse operating parameters of the motor of the circuit breaker motor operating mechanism, respectively configuring the expected voltage of one of the two non-zero phase windings to zero and determining the expected voltages of the other two phase windings based on the inverse current, until multiple sets of current curves and their corresponding curve parameters are obtained.

[0057] Since the motor operating mechanism of this embodiment is a three-phase motor with a three-phase winding, during the inversion process, in order to construct the parameter relationship between the phases of the motor operating mechanism during the inversion process, a relationship model is constructed to obtain the motor inversion parameters on each winding; in the process of configuring the inversion operation parameters, the status of different phases participating in the operation needs to be considered to ensure that accurate motor inversion parameters are obtained.

[0058] Specifically, the process returns to step S101, and the desired voltage and polarity of each phase winding are reconfigured based on the operating characteristics of the motor operating mechanism, so that the rotation direction of the motor operating mechanism is the direction of the limit block of the motor operating mechanism. Steps S102 to S104 are repeated until three different sets of current curves and their corresponding curve parameters are obtained. In the process of returning to reconfigure the desired voltage and polarity, if the desired voltage of the A-phase winding is first configured to be zero and the desired voltages of the B-phase and C-phase windings are determined based on the inverted current, then after returning, the desired voltage of the B-phase or C-phase winding is configured to be zero and the desired voltages of the other two phases A and C or A and B are determined based on the inverted current, until three different sets of current curves and their corresponding curve parameters are determined, thereby obtaining three sets of corresponding parameter relationships.

[0059] Step S106 , constructing a functional relationship model including motor inversion parameters, and solving the functional relationship model based on each set of curve parameters and the actual voltage corresponding to each winding to obtain the motor inversion parameters of the corresponding phase winding.

[0060] Among them, the functional relationship model of the motor inversion parameters is constructed based on the three groups of corresponding parameter relationships determined in step S105, and the three groups of parameter relationships respectively include the parameter relationship between AB phases, the parameter relationship between BC phases, and the parameter relationship between AC phases; the functional relationship model of the motor inversion parameters contains the motor inversion parameters to be solved. By solving the functional relationship model of the motor inversion parameters with each group of curve parameters and the actual voltage corresponding to each winding, the motor inversion parameters of phases A, B, and C on the motor operating mechanism can be obtained respectively.

[0061] Specifically, a functional relationship model of the motor inversion parameters is constructed based on the corresponding parameter relationships of the three groups, and each group of steady-state current values, time constants and the actual voltage corresponding to each winding are substituted into the functional relationship model of the motor inversion parameters to obtain the inversion resistance and inversion inductance of each phase winding.

[0062] In the above-mentioned motor parameter inversion method based on the circuit breaker vector control system, according to the mechanical structure of the circuit breaker operating mechanism, by configuring the inversion operating parameters of the circuit breaker motor operating mechanism, combined with the spring reaction force when closing the motor operating mechanism and the self-closing force characteristics when opening the motor operating mechanism, the motor operating mechanism is made relatively static during the inversion process to prevent the faulty motor from causing damage to the power system; then, according to the inversion operating parameters, a control signal is generated to control the motor operating mechanism to be in a voltage dynamic equal state, and then the bus voltage is collected, and the actual voltage of each winding is determined according to the bus voltage and the control signal, and the three-phase winding voltage is collected. The actual current is fitted according to the actual current to the current curve of the motor operating mechanism during the inversion process, and the curve parameters of the current curve are determined; finally, a functional relationship model including the motor inversion parameters is constructed, and the functional relationship model is solved based on each set of curve parameters and the actual voltage corresponding to each winding to obtain the motor inversion parameters of the corresponding phase winding; the entire process is based on the original vector control system of the operating mechanism and adopts an open-loop PWM control method. There is no need to add additional structures and circuits. The operation is simple and the reliability is high. In addition, based on the solution of the curve parameters, the accuracy of the resistance and inductance inversion of the final motor is improved.

[0063] In one embodiment, Figure 2 As shown, step S101 includes steps S201 to S204. Among them:

[0064] Step S201: obtaining normal operating parameters of the circuit breaker operating mechanism.

[0065] The normal operating parameters of the circuit breaker operating mechanism refer to the parameters of the circuit breaker operating mechanism during normal operation. These parameters include, but are not limited to, the peak current of the circuit breaker operating mechanism during normal operation and the normal resistance of the motor. These parameters can generally be obtained by consulting the relevant technical manual or the circuit breaker nameplate.

[0066] Step S202: configuring the inversion current according to the peak current.

[0067] Among them, the peak current refers to the maximum current that can be reached at the moment when the motor operating mechanism is working. The peak current can be obtained based on the acquisition or the rated current of the motor operating mechanism.

[0068] Specifically, the peak current of the motor operating mechanism is determined, and the inversion current of the motor operating mechanism during the inversion process is configured based on the peak current. More specifically, in the specific implementation of this embodiment, the inversion current is set to 20% of the peak current. In this way, the current value generated by the motor operating mechanism during the inversion process is much smaller than the current during normal operation of the motor operating mechanism, thereby consuming less capacitor energy, which is beneficial to improving the safety of the inversion process. Of course, it is understandable that in other embodiments, the ratio of the inversion current to the peak current can also be set according to actual conditions, such as setting the inversion current to other values ​​such as 15%, 18%, or 22% of the peak current. It is only necessary to ensure that the current value generated by the motor operating mechanism during the inversion process is much smaller than the current during normal operation of the motor operating mechanism.

[0069] In step S203 , the desired voltage of one phase winding is configured to be zero, and the desired voltages of the other two non-zero phase windings are configured according to the inversion current and the normal resistance of the motor operating mechanism.

[0070] The normal resistance of the motor operating mechanism is the resistance of each phase when the motor operating mechanism operates normally, and may be the rated resistance of the motor operating mechanism, which can be obtained by referring to a relevant technical manual or the nameplate of the circuit breaker.

[0071] Specifically, taking phase A as an example, the desired voltage of phase A of the three-phase winding of the motor operating mechanism is set to zero. In this case, phases B and C are referred to as non-zero phase windings. The desired voltages of phases B and C are determined based on Ohm's law, the set inversion current, and the obtained normal resistances of phases B and C. Similarly, when the desired voltages of phases B and C are set to zero, the desired voltages of the other two non-zero phase windings are determined in the same manner as described above and will not be further described here.

[0072] Step S204 , performing Clark transformation and Park transformation on the non-zero phase winding and configuring the polarity of the desired voltage according to the transformation results, so that the rotation direction of the motor of the operating mechanism is limited to the direction toward the limit block of the operating mechanism and the operating mechanism is kept stationary during the inversion process.

[0073] Among them, the Clark transformation is used to transform the three-phase stator current (i.e., the inversion current in this embodiment) from the three-phase stationary coordinate system (i.e., the ABC coordinate system) to the two-phase stationary coordinate system (i.e., the αβ coordinate system); the Park transformation is used to transform the current component in the two-phase stationary coordinate system to the two-phase rotating coordinate system (i.e., the dq coordinate system), wherein the d-axis is consistent with the direction of the motor rotor magnetic flux, and the q-axis is perpendicular to the d-axis.

[0074] Specifically, the inversion current of each phase in the three-phase winding is subjected to Clark transformation to convert the inversion current in the three-phase stationary coordinate system into the two-phase stationary coordinate system, thereby obtaining the current components of the inversion current in each direction in the two-phase stationary coordinate system.

[0075] In an exemplary embodiment, the expression of Clark transform is as follows:

[0076] (1)

[0077] in, are the physical quantities of the motor on the α-axis and β-axis in the αβ coordinate system, They are the physical quantities of the motor on the A-axis, B-axis and C-axis in the ABC coordinate system, including the motor's current, voltage, magnetic flux, etc.

[0078] Based on the current components of the inverted current in each direction in the two-phase stationary coordinate system obtained by the Clark transform, a Park transform is performed on the current components to transform the current components in the two-phase stationary coordinate system into a two-phase rotating coordinate system (i.e., a synchronous coordinate system or a dq coordinate system). Combined with the point angle of the motor operating mechanism, the current and direction of the inverted current in the two-phase rotating coordinate system are obtained. Based on this current direction, the polarity of the desired voltage of the corresponding winding is determined so that the polarity of the desired voltage can be adjusted to ensure that the rotation direction of the motor of the operating mechanism is limited to the direction toward the limit block of the operating mechanism.

[0079] In an exemplary embodiment, the expression of Park transform is as follows:

[0080] (2)

[0081] in, are the physical quantities of the motor on the d-axis and q-axis in the synchronous coordinate system or dq coordinate system, including the motor's current, voltage, magnetic flux, etc. is the electrical angle of the motor rotor.

[0082] In this embodiment, the normal operating parameters of the circuit breaker motor operating mechanism are obtained, the inversion current is configured according to the peak current, and then a suitable expected voltage is set according to the inversion current. The polarity of the expected voltage of each phase winding is obtained by transforming the inversion current, so that the motor is controlled so that the electromagnetic torque of the motor and the reaction force of the limit block are offset, thereby maintaining the static stability of the motor operating mechanism during the inversion process and preventing the faulty motor from causing further damage to the mechanism. In addition, the current value generated during the inversion process is much smaller than the current during normal operation of the circuit breaker motor operating mechanism, the required capacitor energy consumption is small, and the safety is high.

[0083] In one embodiment, Figure 3 As shown, step S102 includes steps S301 to S304. Among them:

[0084] Step S301: Acquire characteristic parameters of the PWM controller.

[0085] The characteristic parameters of the PWM controller include the high-level voltage, cycle, and high-level duration of the PWM control signal output by the PWM controller.

[0086] Step S302 , determining the duty cycle of the PWM control signal of the corresponding phase winding according to the desired voltage of each phase winding and the period and high-level duration of the PWM control signal of the PWM controller, and controlling the operation of the motor operating mechanism based on the PWM control signal.

[0087] The duty cycle of a PWM control signal refers to the ratio of the duration of a high-level voltage to the total duration of the PWM control signal's control cycle. This ratio determines the average voltage output by the PWM controller. The duty cycle can be determined by the ratio of the comparison value of the PWM control signal to the maximum value of the PWM control signal (typically the maximum count value of the PWM controller). The comparison value of the PWM control signal serves as the duty cycle setting value, which in turn sets the duty cycle of the PWM control signal. By adjusting the duty cycle of the PWM control signal, the actual voltage level received by the motor windings (i.e., the equivalent voltage of each phase winding) can be adjusted, thereby controlling the operation of the circuit breaker operating mechanism.

[0088] Specifically, the duty cycle of the PWM control signal of different phase windings is calculated based on the expected voltage of each phase winding determined in step S101 and the period and high-level duration of the PWM control signal obtained in step S301, and a PWM control signal with a corresponding duty cycle is generated by a PWM controller to control the motor operating mechanism based on the PWM control signal.

[0089] Step S303 : determining the equivalent voltage of each phase winding of the circuit breaker operating mechanism according to the high-level voltage, cycle, and high-level duration of the PWM control signal.

[0090] The equivalent voltage of each phase winding refers to the average voltage on the equivalent winding of the motor operating mechanism.

[0091] Specifically, the equivalent voltage of each phase winding of the circuit breaker operating mechanism is determined according to the high-level voltage, cycle and high-level duration of the PWM control signal to control the motor operating mechanism.

[0092] In an optional embodiment, the equivalent voltage is expressed as:

[0093] (3)

[0094] in, is the equivalent voltage, is the high level voltage of the PWM control signal, is the high level duration, is the period of the PWM control signal.

[0095] Step S304 , determining the deviation between the equivalent voltage of each phase winding of the motor operating mechanism and the desired voltage of the corresponding phase, and adjusting the duty cycle of each phase PWM signal according to the deviation to make the equivalent voltage of each phase winding of the motor operating mechanism equal to the desired voltage of the corresponding phase.

[0096] Among them, the deviation between the equivalent voltage of each phase winding of the motor operating mechanism and the expected voltage of the corresponding phase refers to the difference between the average voltage on each phase winding of the motor operating mechanism under the actual control of the PWM control signal and the expected voltage configured on the corresponding phase winding. According to the difference, the required duty cycle of the PWM signal can be calculated, and then the PWM controller is controlled to generate a PWM control signal with a corresponding duty cycle and output it to the control end of the inverter to dynamically adjust the actual operating state of the motor operating mechanism during the inversion process, so that the actual operating state of the motor operating mechanism is similar to or the same as the expected inversion process, thereby ensuring the accuracy of subsequent parameter calculations.

[0097] Specifically, the deviation between the equivalent voltage of each phase and the corresponding expected voltage is calculated based on the equivalent voltage of each phase winding of the motor operating mechanism and the expected voltage of the corresponding phase winding, and the corresponding duty cycle is calculated based on the deviation. The larger the duty cycle, the higher the corresponding equivalent voltage, and the smaller the duty cycle, the lower the corresponding equivalent voltage. Based on this, the size of the equivalent voltage of each winding can be adjusted by adjusting the size of the duty cycle, thereby reducing the deviation between the equivalent voltage of each phase and the corresponding expected voltage, so that the voltage on the equivalent winding is equal to or close to the expected voltage.

[0098] In this embodiment, characteristic parameters of the PWM controller are obtained; a PWM control signal is generated according to the desired voltage of each phase winding and the characteristic parameters of the PWM controller to control the action of the motor operating mechanism; and the equivalent voltage of each phase winding of the motor operating mechanism is determined; and the duty cycle is adjusted based on the deviation between the equivalent voltage and the desired voltage so that the equivalent voltage of each phase winding of the motor operating mechanism is equal to the desired voltage of the corresponding phase. The entire process is implemented based on the original three-closed-loop vector control system of the circuit breaker, does not require the addition of additional hardware circuits and sensors, adopts open-loop control, does not require feedback, and has a simple control method.

[0099] In one embodiment, Figure 4 As shown, step S104 includes steps S401 to S403.

[0100] Step S401 : collecting actual currents of the three-phase windings at a first preset interval as a collection period, and fitting a current curve in a motor inversion process according to the actual currents of the three-phase windings.

[0101] Among them, the first preset interval is obtained based on the custom setting, and the acquisition period refers to the period of collecting the actual current flowing through the three-phase winding during the inversion process, so as to facilitate the fitting of the current curve during the inversion process and obtain the relationship between the actual current and time.

[0102] Specifically, a first preset interval is set and the acquisition period is determined based on it. The actual current of the three-phase winding is collected once in each acquisition period to obtain a series of actual current values. According to the series of actual current values, the current curve of the three-phase winding during the inversion process can be fitted.

[0103] In an exemplary embodiment, a specific method for fitting the current curve during the motor inversion process is as follows:

[0104] Set an acquisition cycle; determine in sequence the first current value of the motor winding in the first stage and the second current value in the second stage of each acquisition cycle; fit each first current value to obtain a first curve and fit each second current value to obtain a second curve; determine the acquisition time of the actual current of the three-phase winding in the acquisition cycle, and determine the first curve or the second curve as the current curve of the actual current of the three-phase winding in the motor inversion process according to the acquisition time.

[0105] Since the phase voltage of the non-zero phase winding of the motor operating mechanism is maintained near the desired voltage during the inversion process under the control of the PWM control signal, at this time, the resistance and inductance of the two non-zero phases are connected in series to form a first-order circuit, and cooperate with the capacitor in the circuit breaker to form a first-order charge and discharge circuit to periodically charge and discharge the inductance in the winding until the actual current region stabilizes.

[0106] The acquisition cycle consists of a first phase and a second phase, during which the motor windings alternate. The first phase is defined as the charging phase, where the capacitors charge the inductors of the two non-zero phases, while the second phase is defined as the discharging phase, where the two non-zero phases discharge through the inductors. This cycle repeats, causing the motor windings to operate in alternating cycles of charging and discharging.

[0107] More specifically, since the motor's windings operate in alternating cycles of charge and discharge:

[0108] In the first stage of the first acquisition cycle, the capacitor charges the inductors of the two non-zero phases. During this stage, the current of the two non-zero phase windings rises from zero to a first current value. Due to the presence of the inductors, the first current value at this time has not reached stability. In the second stage of the first acquisition cycle, the inductors of the two non-zero phases discharge. During this stage, the current of the two non-zero phase windings drops from the first current value to the first second current value. Similarly, due to the presence of the inductors, the first second current value at this time has not dropped to zero and has not reached stability.

[0109] In the first stage of the second acquisition cycle, the capacitor charges the inductors of the two non-zero phases again. During this stage, the current of the two non-zero phase windings increases from the first second current value to the second first current value. At this time, the second first current value has not yet reached stability; in the second stage of the second acquisition cycle, the inductors of the two non-zero phases are discharged again. During this stage, the current of the two non-zero phase windings decreases from the second first current value to the second second current value. At this time, the second second current value has not decreased to the first second current value, nor has it reached stability.

[0110] This cycle is repeated until the Kth first current value and the Kth second current value obtained in the Kth acquisition period tend to be stable, thereby obtaining a series of first current values ​​and a series of second current values.

[0111] The first current values ​​are fitted into a first curve in chronological order, and the second current values ​​are fitted into a second curve in chronological order. Since the first current values ​​represent the maximum current value that can be reached on the motor winding during the corresponding acquisition period, and the second current values ​​represent the minimum current value that can be reached on the motor winding during the corresponding acquisition period, the first curve obtained by fitting is the upper envelope of the current curve, and the second curve is the lower envelope of the current curve.

[0112] The acquisition time of the actual current of the three-phase winding is determined within the acquisition period, and the first curve or the second curve is determined as the current curve of the actual current of the three-phase winding during the motor inversion process according to the acquisition time. For example, when the acquisition time of the actual current of the three-phase winding is the initial time of the acquisition period, the actual current value acquired is the current value at the beginning of the first stage, and the actual current acquired at this time is the second current value. The current curve obtained thereby is approximate to the second curve, and the second curve can be determined as the current curve; and when the acquisition time of the actual current of the three-phase winding is the middle of the acquisition period, the actual current value acquired is the current value at the beginning of the second stage, and the actual current acquired at this time is the first current value. The current curve obtained thereby is approximate to the first curve, and the first curve can be determined as the current curve.

[0113] Step S402 : sampling the current curve with a second preset interval as a sampling period to obtain a sampling data set including a plurality of time-current data points.

[0114] The second preset interval is obtained based on a custom setting, and the sampling period refers to the period of sampling data on the current curve during the inversion process, so as to obtain a number of time-current data points to form a sampling data set for subsequent solution.

[0115] Specifically, a second preset interval is set and used to determine the sampling period. The current curve is sampled in each sampling period to obtain a series of time-current data points including the sampling moment and the current value at that moment to form a sampling data set for subsequent calculations.

[0116] Step S403 , defining initial values ​​of curve parameters and constructing a criterion function, iteratively solving the criterion function using the sampled data set until the criterion function meets preset conditions or reaches a maximum number of iterations, and outputting the curve parameters.

[0117] The quasi-group function is used to measure the quality of the curve fit, and the criterion function satisfies the preset condition of whether the solution of the criterion function is within the set group minimum error range. In specific implementations, the criterion function can be one of the criterion functions including but not limited to the residual sum of squares and the Bayesian information criterion.

[0118] Specifically, the initial values ​​of the curve parameters are set, that is, the initial values ​​of the steady-state current value and the time constant are set, which serve as parameters to be determined in the fitting estimation process; a criterion function is constructed based on the curve parameters and the minimum error range of the criterion function is set or the maximum number of iterations is set; the value of the criterion function is solved using the time-current data points in the sampling data set; it is judged whether the solution result is within the minimum error range or whether the maximum number of iterations is reached. If so, the curve parameters at this time are output to obtain the final steady-state current value and time parameters. If not, the curve parameters are returned to be adjusted and the value of the criterion function is continued to be solved using the time-current data points in the sampling data set. The solution result is judged and it is iterated until the criterion function meets the preset conditions or the maximum number of iterations is reached, and the curve parameters are output to obtain the final steady-state current value and time parameters.

[0119] In this embodiment, the current curve of the motor operating mechanism during the inversion process is obtained by fitting the actual current of the three-phase winding; and the current curve is sampled to obtain a sampling data set containing several time-current data points. Finally, the sampling data set is used to solve the criterion function to obtain the curve parameters, which are used as the data of the subsequent model to solve the motor inversion parameters. This can reduce the impact of data anomalies caused by individual measurement errors on the inversion results, thereby reducing the error of current curve fitting and ensuring the accuracy of the curve parameters.

[0120] In one embodiment, Figure 5 As shown, step S106 includes steps S501 to S502.

[0121] Step S501: constructing a functional relationship model including motor inversion parameters.

[0122] The functional relationship model of the motor inversion parameters is used to characterize the relationship between the motor inversion parameters and the steady-state current value, time constant, and actual voltage of each winding of each current curve in the above steps. The functional relationship model includes a first functional relationship and a second functional relationship. The first functional relationship expresses the equational relationship between the steady-state current value and the time voltage of each winding and the inversion resistance of each phase winding, which together can be used to obtain the inversion resistance of each phase winding; the second functional relationship expresses the equational relationship between the inversion resistance and inversion voltage of each phase winding and the time constant of each current curve, which together can be used to obtain the inversion inductance of each phase winding.

[0123] Specifically, a first relationship function corresponding to each phase winding is constructed based on the relationship between the steady-state current value of each current curve and the time voltage of each winding and the inversion resistance of each phase winding; a second relationship function corresponding to each phase winding is constructed based on the relationship between the inversion resistance and inversion voltage of each phase winding and the time constant of each current curve; and a functional relationship model including the inversion resistance and inversion inductance of the motor is constructed based on each first relationship function and each second relationship function.

[0124] Step S502: Solve the first functional relationship based on each group of steady-state current values ​​and the corresponding actual voltage to obtain the inverse resistance of each phase winding, and solve the second functional relationship based on each group of time constants and the inverse resistance of each phase winding to obtain the inverse inductance of each phase winding.

[0125] Specifically, the steady-state current value and time constant of each current curve determined in step S104 and the actual voltage of each phase winding determined in step S103 are substituted into the corresponding first relationship function or the second relationship function, and the first relationship functions and the second relationship functions are combined. The first relationship functions and the second relationship functions are solved to obtain the inverse resistance and inverse inductance on each phase winding.

[0126] In this embodiment, a functional relationship model is formed by constructing a first functional relationship and a second functional relationship containing motor inversion parameters; the first functional relationship is solved according to each group of steady-state current values ​​and the corresponding actual voltage to obtain the inversion resistance of each phase winding, and the second functional relationship is solved according to each group of time constants and the inversion resistance of each phase winding to obtain the inversion inductance of each phase winding. During the model construction process, by controlling the conduction and working status of different phase bridge arms, pairwise related relationship expressions can be constructed respectively. By combining all the relationships, the inversion resistance and induction of each phase winding can be obtained. The calculation process is simple, fast and highly accurate.

[0127] The motor parameter inversion method based on the circuit breaker vector control system of this embodiment is described below for the convenience of understanding by those skilled in the art. Figure 6 The hardware structure diagram of the circuit breaker motor operating mechanism is provided. The method of this embodiment is based on Figure 6 The circuit breaker motor operating mechanism shown is realized; at the same time, Figure 7 The control principle diagram of the circuit breaker vector control system is provided. The whole process of the method of this embodiment is based on Figure 7 The circuit breaker shown is controlled by the original vector control system, without setting up additional control structure or circuit. It adopts open-loop PWM control method and does not require feedback. The entire control process is simple and reliable.

[0128] Next, combine Figure 6 and Figure 7 The specific structure and control theory of the present invention are further described using a specific embodiment based on a motor operating mechanism in which a single-phase resistor and inductor are connected in series in a three-phase winding of a permanent magnet synchronous motor and the three-phase windings are connected in a star-shaped topology. It should be understood that the following description is merely illustrative and does not constitute a specific limitation of this application.

[0129] Please refer to Figure 6 The motor operating mechanism of this embodiment includes an energy storage capacitor module 601, an inverter module 602, a signal acquisition module 603, a drive module 604, a filter and signal conversion module 605, a control module 606 and a motor 607 (operating mechanism). The control module 606 is connected to a computer 609 (terminal) via a communication interface 608.

[0130] The energy storage capacitor module 601 includes a rectifier circuit and a capacitor. The capacitor provides an energy source for closing and opening the motor 607 through charging and discharging. The capacitor is connected to the inverter module 602, which includes three bridge arms connected to the three-phase windings of the motor 607. Each bridge arm is formed by two upper and lower IGBTs. Each bridge arm controls one phase of the motor winding. The gate turn-on and turn-off signals of the IGBT are generated by the control module 606 and input into the inverter module through the drive module 604 to control each phase of the winding. The signal acquisition module 603 uses a Hall sensor to collect capacitance, voltage, and current, and uses a photoelectric encoder to collect the motor rotation angle and transmit it to the control module 606. The capacitance, voltage, and current data are filtered and converted by the signal conversion module 605 and transmitted to the control module, facilitating the control module 606 to process the collected data and generate the corresponding PWM control signal. In specific implementation, the control module 606 may use a TMS320F28335 chip to implement functions such as processing of collected signals and calculation of control algorithms.

[0131] Please refer to Figure 7 The vector control system of the circuit breaker in this embodiment is a three-closed-loop vector control system. The three closed loops include a position loop, a speed loop and a torque loop from the outside to the inside. The torque loop includes two current loops: the quadrature-axis current loop and the direct-axis current loop.

[0132] The position loop receives the external position command, i.e., the initial position command for the motor, and compares the actual motor position with the commanded position, generating a position error signal and a corresponding speed command. This position error signal and speed command serve as inputs to the speed loop, adjusting the motor's speed and direction, thereby achieving precise control of the motor's position. The speed loop receives the position error command and the adjusted speed command generated by the position loop, and compares the actual motor speed with the commanded speed, generating a speed error signal and a corresponding current command. This speed error signal and current command serve as inputs to the torque loop (primarily the quadrature-axis current loop; the direct-axis current loop has a desired input current of zero) to adjust the motor's current, thereby achieving precise control of the motor's speed. The quadrature-axis current loop receives the speed error signal and current command generated by the speed loop and controls the motor's current to follow the current command. By precisely controlling the motor's current, precise control of the motor's torque is achieved, ensuring stable motor operation.

[0133] Specifically, the quadrature-axis current loop and the direct-axis current loop are independently controlled by a PI controller. The quadrature-axis and direct-axis current component information is obtained by collecting the three-phase stator current (in this embodiment, the determined inversion current) and transforming it through Clark transform and Park transform. After calculation by the control module, the quadrature-axis and direct-axis voltage outputs are output. The voltage component in the αβ coordinate system (i.e., the desired voltage in this embodiment) is further obtained through Park inverse transform. Finally, the space voltage vector pulse width modulation (SVPWM) module is used to generate corresponding PWM control signals to control the conduction and shutdown of the IGBT in the inverter module, thereby driving the permanent magnet synchronous motor to rotate.

[0134] When the limit block of the motor operating mechanism is in the maintained position in the open state, the control system can make the motor rotate clockwise through vector control. Similarly, the control system can make the motor rotate counterclockwise by controlling the conduction and shutdown of the six IGBTs in the drive inverter module. At this time, the motor cannot move due to the action of the limit block and is in a stalled state. The electrical angular velocity of the motor is zero, and the permanent magnet will not be able to generate back electromotive force on the stator winding of the motor, thereby keeping the motor operating mechanism stationary.

[0135] Please refer to Figure 8 , which is a schematic diagram of the principle of the motor parameter inversion method based on the circuit breaker vector control system of this embodiment. In combination with the hardware structure of the circuit breaker motor operating mechanism and the circuit breaker vector control system, the steps of a specific example of the method of this embodiment are as follows:

[0136] First, the initial state parameters of the motor operating mechanism are obtained, and based on the initial state parameters of the motor operating mechanism and the vector control system of the above-mentioned circuit breaker, the desired voltages of the B-phase winding and the C-phase winding are determined, and the desired voltage of the A-phase winding is set to zero. The control process of the desired voltages of the B-phase winding and the C-phase winding is described above and will not be repeated here.

[0137] Then, based on the operation of the vector control system of the circuit breaker, the upper IGBT and the lower IGBT of the A-phase bridge arm are kept turned off, that is, and (in, are the gate switching signals of the upper IGBT and lower IGBT of the A-phase bridge arm respectively).

[0138] Then, the vector control system outputs the corresponding PWM control signal to control the inverter module according to the desired voltage of the B-phase winding and the C-phase winding and the bus voltage, so that the equivalent voltage position of the B-phase winding and the C-phase winding is near the desired voltage of the corresponding phase. At this time, the B-phase winding and the C-phase winding cooperate to form a first-order circuit with inductance and resistance in series, and the stator current of the B-phase winding and the C-phase winding conforms to the first-order circuit characteristics.

[0139] Based on the first-order circuit composed of the above-mentioned inductor and resistor in series, the gate signal of the A-phase bridge arm is and , , (in, is the voltage between the B-phase winding and the C-phase winding, Under the condition that (is the expected voltage of phase C winding), in one acquisition cycle, the current flow direction of the motor stator winding is as follows: Figure 9 As shown. Since the expected voltage of phase C is zero (i.e. ), so the upper IGBT of the C-phase bridge arm is turned off and the lower IGBT is turned on. Figure 9 In (a), since the upper IGBT of the B-phase bridge arm is turned on and the lower IGBT is turned off, at this time, the capacitor, the B-phase winding and the C-phase winding form a path, and the capacitor charges the inductors of the B-phase and C-phase to form a first-order charging circuit; Figure 9 In (b), since the upper IGBT of the B-phase bridge arm is turned off and the lower IGBT is turned on, at this time, the B-phase winding and the C-phase winding form a path and discharge through the inductor.

[0140] Thus, the motor current waveform and the control switch signal are obtained as follows: Figure 10 As shown in (b), the stator winding of the motor works in the case of alternating charge and discharge cycles. In the first stage of the first acquisition cycle (i.e., the charging stage, the charging time is ), the winding current (here is the first current value) has not reached stability, and in the second stage of the first acquisition cycle (i.e., the discharge stage, the discharge time is ), the winding current (here the second current value) does not drop to zero and does not reach stability.

[0141] Therefore, in the first stage of the first acquisition cycle, the capacitor charges the inductors of the two non-zero phases, and the winding current increases from zero to a first current value.

[0142] In an optional embodiment, the first current value is expressed as:

[0143] (4)

[0144] in, is the first current value, is the steady-state current value reached after long-term power-on. is the time of the first stage, i.e. charging time, is the time constant.

[0145] In the second phase of the first acquisition cycle, the inductor discharges and the winding current decreases from a first current value to a first second current value.

[0146] In an optional embodiment, the first second current value is expressed as:

[0147] (5)

[0148] in, is the first second current value, is the time of the second stage, i.e. the discharge time.

[0149] In the first stage of the second acquisition cycle, the capacitor charges the inductors of the two non-zero phases again, and the winding current increases from the first second current value to the second first current value.

[0150] In an optional embodiment, the second first current value is expressed as:

[0151] (6)

[0152] in, is the second first current value.

[0153] In the second phase of the second acquisition cycle, the inductor is discharged again, and the winding current decreases from the second first current value to the second second current value.

[0154] In an optional embodiment, the second current value is expressed as:

[0155] (7)

[0156] in, is the second second current value.

[0157] This cycle repeats until, in the first stage of the Kth acquisition cycle, the capacitor charges the inductors of the two non-zero phases again, and the winding current increases from the K-1th second current value to the Kth first current value.

[0158] In an optional embodiment, the Kth first current value is expressed as:

[0159] (8)

[0160] in, is the Kth first current value, is the number of the first current value or the second current value, The collection cycle.

[0161] In the second stage of the Kth acquisition cycle, the inductor is discharged again, and the winding current decreases from the Kth first current value to the Kth second current value.

[0162] In an optional embodiment, the Kth second current value is expressed as:

[0163] (9)

[0164] in, is the Kth second current value.

[0165] Based on the above, the series in formula (8) is a geometric progression, and its sum is , so the current that increases and decreases during the Kth acquisition cycle can be expressed as:

[0166] (10)

[0167] Combined with the above analysis, Figure 10 The upper and lower envelopes of the current curve in (a) can be expressed as:

[0168] (11)

[0169] in, and The upper and lower envelopes of the current curve are The value at the moment.

[0170] In this embodiment, the actual current of the winding is collected once at the initial moment of each collection cycle. In this way, the final fitted current curve is approximately the lower envelope. The current curve is processed using the least squares method. The current waveform of the first-order circuit with an inductor and a resistor in series is as follows: Figure 11 As shown, based on this, the resistance can be obtained as the voltage divided by the steady-state current value, and the inductance value can be obtained according to the time constant, thereby solving the steady-state current value and time constant of the current curve.

[0171] In an optional embodiment, when processing the current curve using the least squares method, the residual square sum is selected as a criterion function to estimate the steady-state current value and the time constant. In this embodiment, the criterion function is expressed as:

[0172] (12)

[0173] in, is the criterion function, for The observed quantity, for The output, The information such as steady-state current value and time constant is included in it to realize the estimation and solution of steady-state current value and time constant.

[0174] Finally, the relationship equation between phases B and C can be constructed based on the current curve of the BC phase loop and the expected voltages of phases B and C:

[0175] (13)

[0176] in, is the voltage between the B-phase winding and the C-phase winding, are the resistance values ​​of the inverting resistors of the B-phase and C-phase windings, are the inductance values ​​of the reverse inductance of the B-phase and C-phase windings respectively; is the time constant of the current curve of the BC phase loop; are the steady-state current values ​​of the B-phase and C-phase windings respectively.

[0177] Similarly, by setting the upper and lower IGBTs of the B-phase bridge arm to be constantly off, and the upper and lower IGBTs of the C-phase bridge arm to be constantly off, the above process is repeated to obtain the current curves of the AC phase circuit and the current curves of the AB phase circuit, and based on these, the relationship equations between phases A and C and phases A and B are obtained.

[0178] The relationship equation between phases A and C can be constructed based on the current curve of the AC phase loop and the expected voltages of phases A and C:

[0179] (14)

[0180] in, is the voltage between the A-phase winding and the C-phase winding, are the resistance values ​​of the inverting resistors of phase A and phase C windings, are the inductance values ​​of the inverting inductance of the A-phase and C-phase windings respectively; is the time constant of the current curve of the AC phase circuit; are the steady-state current values ​​of phase A and phase C windings respectively.

[0181] According to the current curve of the AB phase circuit and the expected voltage of phase A and phase B, the relationship equation between phase A and phase B can be constructed:

[0182] (15)

[0183] in, is the voltage between phase A winding and phase B winding, are the resistance values ​​of the inverting resistors of phase A and phase B windings respectively, are the inductance values ​​of the inverting inductance of the A-phase and B-phase windings respectively; is the time constant of the current curve of the AB phase circuit; are the steady-state current values ​​of phase A and phase B windings respectively.

[0184] Finally, the functional relationship model of the motor inversion parameters is constructed according to the above formulas (13)(14)(15).

[0185] In an optional embodiment, the functional relationship model of the motor inversion parameters is expressed as:

[0186] (16)

[0187] in, These are the current curves of the AB phase circuit, AC phase circuit, and BC phase circuit respectively.

[0188] Based on the above formula (16), the inverse resistance and inverse inductance corresponding to the A-phase, B-phase, and C-phase loops are obtained jointly.

[0189] In this embodiment, based on the original structure of the circuit breaker and the original vector control system, the motor has small torque fluctuations, a wide speed regulation range, and high current control efficiency during the inversion process. In addition, the motor adopts a three-phase star-connected topology structure, combined with the characteristics of the SVPWM inverter module vector control, to control the corresponding windings to form a first-order circuit with inductance and resistance in series during the inversion process, and based on the desired voltage of the three-phase winding, the corresponding first-order circuit current characteristic curve is obtained, and the internal characteristics of the motor winding resistance and inductance are obtained based on the transient value and stable value of the current curve.

[0190] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0191] Based on the same inventive concept, an embodiment of the present application further provides a motor parameter inversion device based on a circuit breaker vector control system for implementing the aforementioned motor parameter inversion method based on a circuit breaker vector control system. The implementation solution provided by this device is similar to the implementation solution described in the aforementioned method. Therefore, the specific limitations of one or more embodiments of the motor parameter inversion device based on a circuit breaker vector control system provided below can be found in the above-mentioned limitations of the motor parameter inversion method based on a circuit breaker vector control system, and will not be repeated here.

[0192] In one embodiment, Figure 12 As shown, a motor parameter inversion device based on a circuit breaker vector control system is provided, comprising: a parameter configuration module 1201, a control signal generation module 1202, a voltage acquisition and calculation module 1203, a curve generation module 1204, an execution loop module 1205, and a parameter calculation module 1206, wherein:

[0193] Parameter configuration module 1201 is configured to configure the inversion operating parameters of the circuit breaker motor operating mechanism in response to a configuration signal, ensuring that the motor operating mechanism remains relatively stationary during the inversion process. In a specific implementation, at the beginning of the inversion process, the configuration signal is typically a signal that initiates the inversion process, triggering parameter configuration module 1201 to begin parameter configuration. During the inversion process, the configuration signal is typically a configuration signal generated by subsequent execution loop module 1205 to ensure that the corresponding parameters for each phase winding are obtained.

[0194] The control signal generating module 1202 is used to generate a control signal according to the inversion operation parameter, and control the motor operating mechanism to be in a voltage dynamic equalization state based on the control signal.

[0195] The voltage acquisition and calculation module 1203 is used to acquire the bus voltage in the voltage dynamic equal state and determine the actual voltage of each winding according to the bus voltage and the control signal.

[0196] The curve generating module 1204 is used to collect the actual current of the three-phase winding, fit the current curve of the motor operating mechanism during the inversion process according to the actual current, and determine the curve parameters of the current curve.

[0197] The execution loop module 1205 is used to determine whether the number of current curves and their curve parameters meets the preset conditions. If so, an end signal is generated; otherwise, a configuration signal is generated and the parameter configuration module 1201 is jumped until multiple sets of current curves and their corresponding curve parameters are obtained.

[0198] The parameter calculation module 1206 is used to construct a functional relationship model including motor inversion parameters in response to the end signal, and solve the functional relationship model based on each group of curve parameters and the actual voltage corresponding to each winding to obtain the motor inversion parameters of the corresponding phase winding.

[0199] In an optional embodiment, the parameter configuration module 1201 is further used to obtain normal operating parameters of the circuit breaker motor operating mechanism; configure the inversion current according to the peak current; configure the expected voltage of one of the phase windings to zero, and configure the expected voltages of the other two non-zero phase windings according to the inversion current and the normal resistance of the motor operating mechanism; perform Clark transformation and Park transformation on the non-zero phase winding and configure the polarity of the expected voltage based on the transformation results, so that the rotation direction of the motor operating mechanism is limited to the direction toward the limit block of the motor operating mechanism, so that the motor operating mechanism is stationary during the inversion process.

[0200] In an optional embodiment, the control signal generating module 1202 is further used to obtain characteristic parameters of the PWM controller; determine the duty cycle of the PWM control signal of the corresponding phase winding according to the expected voltage of each phase winding and the period and high-level duration of the PWM control signal of the PWM controller, and control the action of the motor operating mechanism based on the PWM control signal; determine the equivalent voltage of each phase winding of the motor operating mechanism according to the high-level voltage, period and high-level duration of the PWM control signal; determine the deviation between the equivalent voltage of each phase winding of the motor operating mechanism and the expected voltage of the corresponding phase, and adjust the duty cycle of each phase PWM signal according to the deviation so that the equivalent voltage of each phase winding of the motor operating mechanism is equal to the expected voltage of the corresponding phase.

[0201] In an optional embodiment, the curve generation module 1204 is further used to collect the actual current of the three-phase winding with a first preset interval as the collection period, and fit the current curve of the motor operating mechanism during the inversion process according to the actual current of the three-phase winding; sample the current curve with a second preset interval as the sampling period to obtain a sampling data set containing a number of time-current data points; define the initial values ​​of the curve parameters and construct a criterion function, use the sampling data set to iteratively solve the criterion function until the criterion function meets the preset conditions or reaches the maximum number of iterations, and output the curve parameters.

[0202] In an optional embodiment, the parameter calculation module 1206 is also used to construct a functional relationship model including motor inversion parameters; the functional relationship model includes a first functional relationship and a second functional relationship; the first functional relationship is solved according to each group of steady-state current values ​​and the corresponding actual voltage to obtain the inversion resistance of each phase winding, and the second functional relationship is solved according to each group of time constants and the inversion resistance of each phase winding to obtain the inversion inductance of each phase winding.

[0203] Each module in the aforementioned motor parameter inversion device based on a circuit breaker vector control system can be implemented in whole or in part through software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in hardware form, or can be stored in a memory in the computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0204] In one embodiment, a computer device is further provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0205] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0206] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with the relevant laws, regulations and standards of relevant countries and regions.

[0207] Those skilled in the art will understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. In particular, any reference to memory, database, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The databases involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the various embodiments provided herein may be, but are not limited to, general-purpose processors, central processing units (CPUs), graphics processing units (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), quantum computing-based data processing logic devices, artificial intelligence (AI) processors, and the like.

[0208] The technical features of the above embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0209] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A motor parameter inversion method based on a circuit breaker vector control system, characterized in that: The method comprises: configuring inversion operating parameters of the circuit breaker motor operating mechanism so that the motor operating mechanism remains relatively stationary during the inversion process; the inversion operating parameters include an inversion current of the motor operating mechanism during the inversion process and an expected voltage of each phase winding and its polarity; the expected voltage of one phase winding of the three-phase winding of the motor operating mechanism is zero, while the expected voltages of the remaining two phase windings are determined based on the inversion current; generating a control signal according to the inversion operation parameter, and controlling the motor operating mechanism to be in a voltage dynamic equalization state based on the control signal; collecting the bus voltage in the voltage dynamic equal state, and determining the actual voltage of each winding according to the bus voltage and the control signal; collecting actual currents of the three-phase windings, fitting a current curve of the motor operating mechanism during the inversion process according to the actual currents, and determining curve parameters of the current curve; Returning to the step of configuring the inversion operating parameters of the circuit breaker motor operating mechanism, respectively configuring the desired voltage of one of the two non-zero phase windings to be zero and determining the desired voltages of the other two phase windings based on the inversion current, until multiple sets of current curves and their corresponding curve parameters are obtained; A functional relationship model including motor inversion parameters is constructed, and the functional relationship model is solved based on each set of curve parameters and the actual voltage corresponding to each winding to obtain the motor inversion parameters of the corresponding phase winding.

2. The method according to claim 1, characterized in that The configuring of the inversion operating parameters of the circuit breaker motor operating mechanism so that the motor operating mechanism is relatively stationary during the inversion process includes: Acquiring normal operating parameters of the circuit breaker motor operating mechanism; the normal operating parameters include the peak current of the motor operating mechanism during normal operation and the normal resistance of the motor operating mechanism; configuring the inversion current according to the peak current; configuring the desired voltage of one phase winding to be zero, and configuring the desired voltages of the other two non-zero phase windings according to the inversion current and the normal resistance of the motor operating mechanism; Clark transformation and Park transformation are performed on the non-zero phase winding and the polarity of the desired voltage is configured based on the transformation results, so that the rotation direction of the motor operating mechanism is limited to the direction toward the limit block of the motor operating mechanism and the motor operating mechanism is kept stationary during the inversion process.

3. The method according to claim 2, characterized in that The voltage dynamic equal state is defined as the equivalent voltage of each phase winding of the circuit breaker motor operating mechanism being equal to the desired voltage of the corresponding phase under the dynamic control of the control signal.

4. The method according to claim 3, characterized in that Generating a control signal according to the inversion operation parameter, and controlling the motor operating mechanism to be in a voltage dynamic stable state based on the control signal includes: Acquire characteristic parameters of the PWM controller; the characteristic parameters include the high-level voltage, cycle, and high-level duration of the PWM control signal output by the PWM controller; Determining the duty cycle of the PWM control signal of the corresponding phase winding according to the desired voltage of each phase winding and the period and high-level duration of the PWM control signal of the PWM controller, and controlling the operation of the motor operating mechanism based on the PWM control signal; determining an equivalent voltage of each phase winding of the motor operating mechanism according to the high-level voltage, cycle, and high-level duration of the PWM control signal; Determine the deviation between the equivalent voltage of each phase winding of the motor operating mechanism and the expected voltage of the corresponding phase, and adjust the duty cycle of each phase PWM signal according to the deviation so that the equivalent voltage of each phase winding of the motor operating mechanism is equal to the expected voltage of the corresponding phase.

5. The method according to any one of claims 1 to 4, characterized in that The collecting the actual current of the three-phase winding, fitting the current curve of the motor operating mechanism during the inversion process according to the actual current, and determining the curve parameters of the current curve includes: collecting the actual current of the three-phase winding at a first preset interval as a collection period, and fitting the current curve of the motor operating mechanism during the inversion process according to the actual current of the three-phase winding; Sampling the current curve at a second preset interval as a sampling period to obtain a sampling data set including a plurality of time-current data points; Initial values ​​of curve parameters are defined and a criterion function is constructed. The criterion function is iteratively solved using the sample data set until the criterion function meets a preset condition or reaches a maximum number of iterations, and the curve parameters are output.

6. The method according to claim 5, characterized in that The collecting the actual current of the three-phase winding at a first preset interval as a collection period, and fitting the current curve of the motor operating mechanism during the inversion process according to the actual current of the three-phase winding includes: Setting an acquisition cycle; the acquisition cycle has a first phase and a second phase, and the windings of the motor operating mechanism alternately operate in the first phase and the second phase; sequentially determining a first current value of each winding in a first phase and a second current value in a second phase of each acquisition cycle; Fitting each first current value to obtain a first curve and fitting each second current value to obtain a second curve; The acquisition time of the actual current of the winding within the acquisition period is determined, and the first curve or the second curve is determined as the current curve of the actual current of the three-phase winding fitting motor operating mechanism during the inversion process according to the acquisition time.

7. The method according to any one of claims 1 to 4, characterized in that The constructing of a functional relationship model including motor inversion parameters, and solving the functional relationship model based on each set of curve parameters and the actual voltage corresponding to each winding to obtain the motor inversion parameters of the corresponding phase winding includes: Constructing a functional relationship model including motor inversion parameters; the motor inversion parameters include an inversion resistance and an inversion inductance of the motor operating mechanism, the curve parameters include a steady-state current value and a time constant corresponding to each current curve, and the functional relationship model includes a first functional relationship expression and a second functional relationship expression; The first functional relationship is solved according to each group of steady-state current values ​​and the corresponding actual voltage to obtain the inverse resistance of each phase winding. The second functional relationship is solved according to each group of time constants and the inverse resistance of each phase winding to obtain the inverse inductance of each phase winding.

8. A motor parameter inversion device based on a circuit breaker vector control system, characterized in that: The device comprises: a parameter configuration module, configured to configure inversion operating parameters of the circuit breaker motor operating mechanism in response to a configuration signal, so that the motor operating mechanism remains relatively stationary during an inversion process; the inversion operating parameters include an inversion current of the motor operating mechanism during the inversion process and an expected voltage of each phase winding and its polarity; the expected voltage of one phase winding of the three-phase winding of the motor operating mechanism is zero, while the expected voltages of the remaining two phase windings are determined based on the inversion current; a control signal generating module, configured to generate a control signal according to the inversion operation parameter, and control the motor operating mechanism to be in a voltage dynamic equalization state based on the control signal; a voltage acquisition and calculation module, configured to acquire the bus voltage when the voltage is dynamically equal, and determine the actual voltage of each winding according to the bus voltage and the control signal; a curve generating module, configured to collect actual currents of the three-phase windings, fit a current curve of the motor operating mechanism during an inversion process according to the actual currents, and determine curve parameters of the current curve; An execution loop module is used to determine whether the number of current curves and their curve parameters meets the preset conditions, and if so, generates an end signal; otherwise, generates the configuration signal and jumps to the parameter configuration module until multiple sets of current curves and their corresponding curve parameters are obtained; A parameter calculation module is used to construct a functional relationship model including motor inversion parameters in response to the end signal, and solve the functional relationship model based on each group of curve parameters and the actual voltage corresponding to each winding to obtain the motor inversion parameters of the corresponding phase winding.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

Images