87 results about "Field weakening" patented technology

The invention discloses a motor multi-parameter online identification and robust control method based on multi-observer cascade. The method comprises the steps of obtaining real-time operation data of the permanent magnet synchronous motor; obtaining a preliminary observation value through a sliding mode observer group; the sliding-mode observer group is constructed based on a mathematical model of the permanent magnet synchronous motor and is used for receiving real-time operation data and synchronously outputting initial observation values of a permanent magnet flux linkage, q-axis inductance and d-axis inductance; then analyzing the preliminary observation value to obtain a flux linkage accurate value, a q-axis inductance accurate value and a d-axis inductance accurate value, and finally performing adaptive control on the permanent magnet synchronous motor according to the flux linkage accurate value, the q-axis inductance accurate value and the d-axis inductance accurate value. According to the method, multiple motor parameters can be synchronously estimated, the limitation that other parameters are assumed to be accurate when a single parameter is identified in a traditional identification method is avoided, adaptive current reference and voltage decoupling are further generated based on the estimated parameters, and robust and stable field weakening control under variable working conditions can be achieved.

The invention discloses a permanent magnet synchronous motor wide speed range model prediction control method and system based on a mean value reduction optimization algorithm, and belongs to the technical field of motor control. According to the method, a discrete mathematical model of the permanent magnet synchronous motor is established under a d-q rotating coordinate system, a q-axis current reference value is generated by an outer ring through a speed PI regulator, and a d-axis current reference value is calculated in combination with a maximum torque per ampere (MTPA) principle and a weak magnetic region voltage constraint; finite control set model prediction control is adopted in an inner ring, enumeration prediction is conducted on candidate voltage vectors of the three-phase voltage source type inverter, a cost function containing a d-axis current error, a q-axis current error and an electromagnetic torque error is constructed, an optimal voltage vector is selected, and a three-phase PWM signal is generated through space vector pulse width modulation to drive a motor. The system is provided with a mean value reduction optimization module, joint optimization is carried out on speed outer ring PI parameters and cost function weight coefficients in the off-line stage, the parameters are stored in a lookup table, and automatic setting of control parameters is achieved. The permanent magnet synchronous motor can improve the dynamic response performance of the rotating speed and the current in the base speed area and the weak magnetic area, reduce the total harmonic distortion of the stator current, improve the voltage utilization rate and the overall operation efficiency of the permanent magnet synchronous motor, and is suitable for occasions such as electric vehicle driving and high-performance servo systems.

The application provides a Park compensation method, device, medium and system of a permanent magnet synchronous motor. The method comprises: adjusting the permanent magnet synchronous motor to a positive rotation speed by using a dynamometer, taking a first preset rotation speed as an interval point, until the highest positive rotation speed, applying a field weakening current to the d-axis of the permanent magnet synchronous motor, obtaining a plurality of first initial angle calibration values respectively, and determining a Park compensation value according to all the first initial angle calibration values; obtaining a plurality of second initial angle calibration values respectively, and determining an angle correction value; determining a Park compensation radian value as a sum value of a compensation value product and an angle correction; and adjusting the rotor position of the permanent magnet synchronous motor by using the Park compensation radian value. Thus, the problem that the torque accuracy of the motor is low due to the angle compensation strategy of the existing scheme is solved.

The invention discloses a quadratic programming-based permanent magnet synchronous motor model prediction field weakening control method and system. The method comprises the following steps of: giving a rotating speed reference value of a current motor, calculating a reference rotating speed of the motor, making a difference between the rotating speed reference value and the reference rotating speed, and obtaining a direct-axis current reference value according to a difference value relationship; according to the current value, the voltage value and the rotating speed value at the current moment, the current value and the rotating speed value at the next moment are calculated, and a current cross term is ignored in the calculation process; establishing a target function of a voltage instruction by combining the current value of the next moment, the rotating speed value of the next moment, the direct-axis current reference value and the rotating speed reference value; the objective function of the voltage instruction is converted into a quadratic optimization problem model with constraints, solving is carried out through a Karush-Kuhn-Tucker optimality condition, and an optimal voltage instruction is obtained; the optimal voltage instruction serves as reference quadrature-axis voltage and reference direct-axis voltage, and a duty ratio control signal used for controlling three-phase output is obtained through calculation; according to the invention, the dynamic response capability, the energy efficiency and the system stability of a weak magnetic region can be improved, and the urgent demand of a modern electric drive system for high-performance control is met.

The application discloses a motor control method, a controller, a motor, a refrigerator, a medium and a program product. A direct-current bus voltage and a cross-axis current of a motor are acquired, and a direct-axis voltage and a cross-axis voltage are acquired. An initial direct-axis current is generated through field weakening control according to the direct-axis voltage, the cross-axis voltage and the direct-current bus voltage. A target frequency disturbance component caused by direct-current bus voltage fluctuation and a direct-current component used for field weakening control are separated from the initial direct-axis current. A phase of the target frequency disturbance component is calculated and optimized to obtain a target alternating current component, with minimization of a harmonic component of the target frequency in the cross-axis current as an optimization target. A direct-axis reference current is synthesized according to the target alternating current component and the direct-current component, and the motor is controlled according to the direct-axis reference current. In the working condition of the direct-current bus voltage fluctuation, energy backflow can be effectively inhibited, current harmonics can be reduced, torque pulsation can be reduced, and the running stability of the motor can be improved.

A vector control method is disclosed in which currents of an electric multiphase machine (183) are represented in a dq-axis coordinate system, comprising the vector control method of injecting a d-axis current based on a q-axis request (140). Furthermore, a corresponding converter and a computer program product are disclosed.

A system and a method operate in a first mode and a second mode. In the first mode, the system and the method control the DC current and quadrature current applied to a motor with an internal permanent magnet to achieve a desired speed and torque over a range of internal operating temperatures of the motor without exceeding a maximum stator current. If a calculated stator current exceeds a maximum stator current, the system and the method operate in the second mode, in which they control the DC current and the stator current to keep the calculated stator current below the maximum stator current.

The invention discloses a simulation modeling method and device for a permanent magnet synchronous motor. The simulation modeling method comprises the following steps: establishing a state equation of the permanent magnet synchronous motor; searching in a preformed first two-dimensional array by taking the stator current as an input quantity to obtain corresponding stator inductance; calculating a stator flux linkage differential value according to a state equation of the permanent magnet synchronous motor and the found stator inductance; integrating the stator flux linkage differential value to obtain a stator flux linkage; and obtaining the adjusted stator current according to the obtained stator flux linkage and the relational expression between the flux linkage and the current. According to the application, the MTPA function can be realized, the values of the inductance and the flux linkage are reduced along with the increase of the current, the MTPA state and the weak magnetic state working area of the real motor can be simulated, and the simulation motor is ensured to be close to the operation condition of the actual motor to the greatest extent.

The invention discloses a field weakening trajectory tracking control method for permanent magnet synchronous motors based on enhanced model predictive current control, comprising: S1, establishing a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system and determining the optimal operating trajectory in the field weakening region; S2, constructing an extended virtual voltage vector set synthesized from the basic voltage vector, and constructing a virtual voltage vector containing continuous components, excess components, and disturbance components as feedback quantities, which are adjusted by the field weakening current controller. d The shaft reference current limits the virtual voltage amplitude within the inverter output voltage limit; S3, a nonlinear extended state observer based on a nonlinear function is designed to estimate the current state and total disturbance in real time, and correct the current prediction model. The optimal voltage vector is selected through a cost function, and a switching pulse sequence is generated to drive the inverter. This invention can effectively reduce current ripple when motor parameters are mismatched and overcome the deviation of the field weakening trajectory when model parameters are mismatched.

This invention discloses an air conditioner and its compressor control method and device. The control method includes: when the compressor is in a field weakening control mode, acquiring the current three-phase current of the compressor; acquiring the current d-axis voltage and current q-axis voltage based on the current three-phase current; processing the current d-axis voltage and current q-axis voltage to obtain a processed voltage signal; multiplying the processed voltage signal by the reciprocal of an adjustment coefficient, and determining the product as a current adjustment bus voltage command; performing power factor correction control based on the current adjustment bus voltage command; further acquiring the current feedback modulation rate for field weakening control, limiting the current feedback modulation rate to obtain a current processed feedback modulation rate; determining the current field weakening control current based on the current processed feedback modulation rate; and executing field weakening control based on the current field weakening control current. Using this invention, the performance of the compressor in different control processes can be improved.

The application provides a motor field weakening control method and system based on limited set model predictive control, can solve the problem that the output voltage of limited control set model predictive control cannot be directly used for closed-loop field weakening control, and comprises the following steps: obtaining operation parameters of a current sampling period of a motor, and predicting dq axis currents of a next sampling period; constructing a reference voltage of the next sampling period, the reference voltage is divided into a sampling voltage component and a transient voltage component, performing boundary judgment on a reference current vector corresponding to the transient voltage component, and determining whether to perform dynamic amplitude limiting processing on the transient voltage component according to a boundary judgment result; adding the sampling voltage component and the processed transient voltage component to obtain a corrected reference voltage, then obtaining a field weakening current component through comparison and closed-loop feedback, superimposing the field weakening current component to obtain a corrected d-axis reference current, and updating the reference current; and obtaining an optimal voltage vector through an evaluation function of limited set model predictive control to perform control.

The invention relates to a method for controlling an electric motor, wherein the method, at least in one field weakening mode, compares a torque request with an actual torque and, based on this, generates a controller output variable which serves to obtain motor control variables by means of which the motor is controlled, and wherein motor operating variables are measured and used to calculate the actual torque. The invention further relates to an associated control device and an associated motor arrangement.

The invention provides a frequency conversion equipment control method, frequency conversion equipment and a computer readable storage medium. The frequency conversion equipment control method comprises the following steps: in response to a field weakening control instruction, determining a field weakening control parameter interval of field weakening control parameters corresponding to a current state; determining a current target parameter based on the field weakening control parameter interval and a preset abnormal parameter interval; the preset abnormal parameter interval comprises abnormal parameters corresponding to noise; and controlling the frequency conversion equipment based on the current target parameter. According to the control method of the frequency conversion equipment, when field weakening control is carried out, the current target parameter is determined based on the field weakening control parameter interval and the preset abnormal parameter interval, and due to the fact that the preset abnormal parameter interval comprises the abnormal parameters corresponding to the noise, the abnormal parameters can be removed when the current target parameter is determined; therefore, the noise of frequency conversion equipment in field weakening control is reduced, and the equipment reliability is improved.

This invention discloses a control method, control device, and air conditioner compressor. The control method includes: acquiring the current three-phase current and current bus voltage of the compressor; acquiring a current adjustment bus voltage command based on the current three-phase current; acquiring a current feedback modulation rate based on the current bus voltage; determining the current feedback modulation rate deviation to be 0 when the current feedback modulation rate is greater than the modulation rate setting and the current adjustment bus voltage command is less than the maximum limit value of the voltage command; otherwise, determining the current feedback modulation rate deviation to be the difference between the modulation rate setting and the current feedback modulation rate; determining a current field weakening control current based on the current feedback modulation rate deviation; performing field weakening control based on the current field weakening control current; and performing power factor correction control based on the current adjustment bus voltage command. Using this invention, the performance of the compressor in different control processes can be improved.

The application discloses a kind of MTPA-weak magnetic feedforward control method, system based on model parameter updating, storeable medium, it is related to motor control field.The present application includes two stages: MTPA stage control and weak magnetic stage control respectively.Specifically, on the basis of MTPA control, judge whether current point is in the overlapping region of voltage limit circle and current limit circle, if meet then continue to execute MTPA mode, if not meet then jump to weak magnetic region control, according to the interrelation of target torque and voltage limit region, current limit region, real-time solution updates the current operating point of weak magnetic area.In the present application, the smoothness of two-stage transition and the responsiveness of the system under varying conditions are improved.In the case of inductance parameter variation, the present application can update the current operating point based on inductance variation in real time, effectively suppress the working condition fluctuation, and show good application prospect.

The invention relates to a system (1) for controlling the operation of an electric motor intended for powering a motor vehicle, comprising a field weakening controller (2) which, during operation, controls the stator flux to achieve field weakening, wherein a loss controller (3) is provided which is configured to control the power loss from a target loss and an actual power loss, the loss controller (3) being configured such that the stator flux is used as the control variable. The invention also relates to a synchronous machine with such a system (1) and a motor vehicle drive with such a synchronous machine. Furthermore, the invention relates to a method for operating an electric motor drive in a motor vehicle, comprising the system (1) according to the invention, which is operated in such a way as to achieve a target power loss.

The application discloses a kind of global control method, device and permanent magnet synchronous motor of permanent magnet synchronous motor, by calibration, the three-dimensional current pulse spectrum of non-field weakening area is obtained, and the three-dimensional current pulse spectrum of field weakening area is also obtained by calculation, wherein, three-dimensional current pulse spectrum is voltage-speed-torque three-dimensional current pulse spectrum, in the first working condition, according to the three-dimensional current pulse spectrum of non-field weakening area, maximum torque current ratio control strategy is used, in the second working condition, according to the three-dimensional current pulse spectrum of field weakening area, maximum torque voltage ratio control strategy is used, on the one hand, non-field weakening area uses the method of calibration to obtain three-dimensional current pulse spectrum, field weakening area obtains three-dimensional current pulse spectrum by calculation, while reducing calibration time, reduce calibration cost, can make the current MAP more accurate, on the other hand, different control strategies are used for different working conditions, reduce the mutual coupling influence of field weakening ring and current ring, greatly improve the reliability and stability of field weakening control.

The application discloses a motor control method, device and system, a motor and an electrical equipment, and belongs to the field of motor control. When a motor enters a field weakening control state, a bus voltage of a frequency converter for controlling the motor is acquired. If a bus voltage drop value in a unit time is detected to exceed a preset voltage value, it is indicated that the bus voltage drops too fast. At this time, if the frequency is directly reduced, the frequency reduction speed is relatively slow, the operating current increases too fast, overcurrent protection is triggered, and the system is shut down. Therefore, the application scheme first increases the carrier frequency of the frequency converter to a preset carrier frequency, and then switches an integral term in a control parameter of the motor to a value corresponding to the preset carrier frequency. In this way, when the frequency is reduced, the frequency reduction speed of the motor can be accelerated, the operating current is prevented from increasing too fast, overcurrent protection is not triggered in the process in which the motor reduces the frequency and exits the field weakening control state, and normal operation of the system is ensured.

This invention provides a dual-layer hybrid structure hybrid magnetic flux-modulated motor, relating to the field of motor design and manufacturing technology. It includes a stator and a rotor disposed inside the stator and rotating relative to it. The stator has an armature winding, and an air gap exists between the rotor and stator. Multiple magnetic pole assemblies are evenly distributed circumferentially inside the rotor. Each magnetic pole assembly includes a first permanent magnet layer and a second permanent magnet layer. The first permanent magnet layer includes a first high-coercivity permanent magnet, and the second permanent magnet layer includes a second high-coercivity permanent magnet and a low-coercivity permanent magnet. The first high-coercivity permanent magnet and the low-coercivity permanent magnet in the second permanent magnet layer form a series structure, while the second high-coercivity permanent magnet and the low-coercivity permanent magnet form a parallel magnetic circuit structure. This invention organically combines "controllable leakage flux" and "memory magnetic flux modulation" through a dual-layer hybrid magnetic circuit structure, enabling the motor to simultaneously possess torque output capability under high load conditions and field weakening speed-enhancing capability under high speed conditions.

The application relates to the technical field of vehicles, in particular to an automatic testing method and device of an electric drive assembly, a vehicle and a storage medium, wherein the method comprises the following steps: receiving an automatic testing instruction of the electric drive assembly, and determining an automatic testing strategy of the electric drive assembly, wherein the automatic testing strategy comprises an MTPA automatic testing strategy and a field weakening automatic testing strategy; the electric drive assembly is automatically tested according to the MTPA automatic testing strategy and the field weakening automatic testing strategy respectively, MTPA automatic testing results and field weakening testing results are obtained, and finally, automatic testing results of the electric drive assembly are generated. Therefore, the problems of low efficiency, high cost and errors in manual performance parameter calibration of the electric drive assembly are solved, and the automatic performance parameter calibration of the electric drive assembly is realized through MTPA testing and field weakening testing.

The invention provides an asynchronous motor field weakening control method and system, a storage medium and a program product, and relates to the technical field of motor control. The given q-axis voltage directly related to the motor torque serves as the feedback quantity of closed-loop control, so that a control system can accurately judge whether the motor is in a high-speed light-load state or not. In the case of light load, the given q-axis voltage is inevitably far lower than the q-axis voltage upper limit set by the system, so that the voltage regulator is prompted to actively exit the saturation region, and the problem that a large number of harmonic waves are generated due to continuous saturation in related technologies is solved. Meanwhile, the basic flux-weakening current generated by the speed inverse ratio model is reserved to serve as a feed-forward item, the dynamic response of the system is guaranteed, dynamic amplitude limiting is conducted on the output of the closed-loop regulator through the feed-forward item, regulation overshoot and oscillation in the dynamic process are prevented, and the response speed and operation stability of flux-weakening control are improved.

This invention discloses a wide-range speed-regulating permanent magnet synchronous motor with unequal stator and rotor lengths, relating to the field of motor technology. It includes a stator, a rotor, and a dynamic effective stacking height switching mechanism. The stator and rotor are unequal in axial length. The dynamic effective stacking height switching mechanism drives the rotor to move axially and dynamically changes the effective stacking height between the stator and rotor. The effective stacking height is the axial overlap length between the stator and rotor, and the initial value of the effective stacking height between the rotor and the stator is less than the axial length of the stator. By employing a staggered arrangement of the rotor and stator with unequal axial lengths, and by dynamically changing the effective stacking height between the stator and rotor, the motor can switch and increase speed between high-speed low-torque and low-speed high-torque operating conditions without relying on field weakening control, thereby improving the stability and reliability of the motor.

This invention discloses a variable frequency air conditioner and its compressor control method and device. The control method includes: when the compressor is in a field weakening control mode, acquiring the current three-phase current and the current bus voltage of the compressor; acquiring a processed voltage signal based on the current three-phase current; multiplying the processed voltage signal by the reciprocal of the adjustment coefficient, and determining the product as a current adjustment bus voltage command; performing power factor correction control based on the current adjustment bus voltage command; further performing amplitude limiting or filtering processing on the current bus voltage to obtain a current processed bus voltage; acquiring a current feedback modulation rate based on the current processed bus voltage; acquiring a current field weakening control current based on the current feedback modulation rate; and executing field weakening control based on the current field weakening control current. Using this invention, the performance of the compressor in different control processes can be improved.

The application discloses a kind of tripper and circuit breaker, specifically relates to low-voltage electrical technology field, including shell, the inside of shell is provided with electromagnetic mechanism, secondary amplification mechanism, adjusting mechanism.The application is through the setting of adjusting cavity and first piston structure, when the temperature in the circuit breaker rises, the expansion of thermal expansion gas is pushed to the direction of fixed plate by first piston, to provide greater thrust for the release of moving iron core, prevent the same thrust under the phenomenon of magnetic field weakening, delay or unable to trip, improve safety, and can be when the temperature in the circuit breaker is too high, release the attraction of moving iron core and static iron core, make circuit breaker trip, so as to play the role of fault protection, further improve safety.

The invention discloses a method for calculating flux weakening control reference current of a permanent magnet motor, and the method comprises the steps: calculating a voltage constraint coefficient according to the voltage of a DC bus, the flux linkage of a permanent magnet and the maximum no-load rotation speed, and representing the voltage limitation degree of a high-speed region; the weak magnetic expected current is directly obtained according to the coefficient, and rapid analysis without additional control links is achieved; the weak magnetic current is corrected by combining the motor resistance and the operation current, so that the adaptability of a high-speed region is improved; and the flux weakening current range is automatically constrained through current amplitude limiting judgment, and the safe operation margin is ensured. Error accumulation of torque control reference current can be avoided, and the control precision of a weak magnetic region is remarkably improved; double mechanisms of dynamic compensation and amplitude limiting protection are adopted to adapt to complex working conditions of a high-speed area, and the anti-interference capability is excellent; an additional PI controller or a torque current calculation module is not needed, the real-time performance is high, and engineering implementation is facilitated; and the voltage constraint is accurately matched, the utilization efficiency of the DC bus voltage is maximized, and higher rotation speed expansion is supported.

The invention discloses an MTPA method-based copper loss optimization control method and device for a permanent magnet synchronous motor without an electrolytic capacitor, and belongs to the field of permanent magnet synchronous motors. The method comprises the steps that q-axis reference current is made to fluctuate in a frequency doubling mode along with bus voltage, and it is ensured that a system obtains a high power factor; the method comprises the following steps: calculating MTPA critical voltage and weak magnetic control critical voltage by combining operation constraint conditions of a permanent magnet synchronous motor without an electrolytic capacitor, dividing each bus voltage fluctuation period into three working areas, namely a weak magnetic control area, a buffer area and an MTPA control area, and giving d-axis reference current in one bus voltage fluctuation period in sections; a feed-forward power compensation mechanism is introduced, the grid-side current quality is improved, and a PWM signal used for controlling the duty ratio of an inverter is generated. The effective improvement of the grid-side current performance is realized, and the MTPA control method can be utilized to reduce the copper loss to the greatest extent.

The invention relates to the technical field of vehicles, in particular to a bus voltage fault diagnosis method and device, a vehicle and a medium. If yes, selecting a bus voltage estimation value obtained by estimation based on a preset permanent magnet synchronous motor back electromotive force model and a bus voltage value of the battery management system as verification reference sources; if the motor is not in the preset weak magnetic working condition, selecting a bus voltage reconstruction value obtained based on inverter switch state reconstruction and a bus voltage value of the battery management system as a verification reference source; and performing multi-source cross verification on the main bus voltage detection value and the auxiliary bus voltage detection value based on the verification reference source to obtain a fault diagnosis result. Therefore, the problem that an existing dual-redundancy bus voltage sensor system cannot accurately position a failure source after a fault occurs is solved, and intelligent fault diagnosis and dynamic fault-tolerant control based on multi-source cross validation are achieved.

The invention discloses a permanent magnet synchronous motor field-weakening control method based on power regulation, and relates to the technical field of motor field-weakening control. The method comprises the following steps: acquiring three-phase current and performing coordinate system conversion; acquiring an actual rotating speed based on motor rotor position information; establishing a power-current mapping relation; constructing an active power ring and a reactive power ring; starting of a reactive power loop is controlled through a threshold range, alpha-beta-axis current reference given is calculated, dq-axis current reference given is obtained through conversion, and the permanent magnet synchronous motor is driven to operate through current loop control and PWM wave generation. A current reference track is obtained through a power mapping relation, a traditional voltage control loop is omitted, a PI controller is adopted to construct a power control loop, good compatibility and execution efficiency are achieved, and field weakening and position-free cooperative operation can be achieved.

The embodiment of the invention discloses a target voltage vector determination method and device of an inverter, equipment and a storage medium, and the method comprises the steps: obtaining a bus voltage value and a three-phase current, carrying out the real-time comparison of a plurality of bus voltage values obtained in a control period, determining the minimum value of the bus voltage according to a comparison result, and obtaining the target voltage vector of the inverter. Determining an initial voltage vector corresponding to the minimum bus voltage value; if the number of the bus voltage values meets a preset sampling frequency, determining an effective voltage value based on the plurality of bus voltage values and the preset sampling frequency, and determining a current field weakening control advance angle based on the three-phase current, a preset control parameter and the initial voltage vector; determining a voltage vector increment according to the current weak magnetic control lead angle, a preset first lead angle threshold value, a preset second lead angle threshold value, a bus voltage minimum value and an effective voltage value, and updating an initial voltage vector based on the voltage vector increment and the bus voltage minimum value to obtain a current target voltage vector, and the accuracy of determining the maximum voltage vector allowed to be output by the inverter is improved.

The invention discloses a motor and a control method and device thereof, a compressor, an air conditioner, a storage medium and a computer program product, and the method comprises the steps: determining the modulation voltage of the motor according to the three-phase current of the motor under the operation condition of the motor; determining a target value of the DC bus voltage of the motor and a flux weakening angle sum of the motor according to the current value of the DC bus voltage of the motor, the AC input voltage of the motor and the modulation voltage of the motor; controlling a driving unit of the PFC circuit according to the target value of the DC bus voltage of the motor so as to control the PFC circuit; and according to the set speed of the motor, the three-phase current of the motor and the flux weakening angle of the motor, a driving unit of the IPM module is controlled so as to control the IPM module. According to the scheme, the target value of the direct-current bus voltage and the flux weakening angle are controlled according to the alternating-current input voltage and the modulation voltage of the motor, efficient operation of the motor at low frequency can be guaranteed, the high-frequency operation requirement can be met, and the energy efficiency of the motor is improved.