10 results about "Rotor time constant" patented technology

The invention relates to the technical field of motor control, and discloses an induction motor rotor time constant adaptive control method, system and device, and the method comprises the steps: determining a rotor time constant estimation value based on the reactive power deviation of a model reference adaptive system; determining a rotor resistance estimation value according to the rotor time constant estimation value and a rotor inductance parameter value obtained in real time; performing low-pass filtering on the rotor resistance estimation value to generate a filtering value; updating a rotor time constant feed-forward value based on the rotor inductance parameter value and the filtering value; and based on the rotor time constant feedforward value, optimizing a convergence process of the rotor time constant estimation value so as to perform indirect vector control of the induction motor. The method has the beneficial effect that the convergence speed and robustness of adaptive identification of the rotor time constant are improved.

The application provides a method and device for adjusting the time constant of an asynchronous motor rotor, and a current correction method, device and system, and relates to the technical field of motor control. The method comprises the following steps: obtaining the rotor electric angular velocity, resistance and inductance; obtaining the three-phase current and three-phase voltage of the motor; using a current model to calculate a first torque according to the rotor d-axis flux, rotor q-axis flux, initial rotor time constant, stator d-axis current and stator q-axis current; using a voltage model to calculate a second torque according to the stator alpha-axis flux, stator beta-axis flux, stator alpha-axis voltage, stator beta-axis voltage, stator alpha-axis current and stator beta-axis current; making the deviation of the first torque relative to the second torque within a preset range to generate a rotor time constant compensation value; and compensating the initial rotor time constant. The application solves the problem of poor torque control accuracy of the asynchronous motor caused by the calculation of the rotor time constant based on the offline measured rotor inductance and resistance for controlling the stator d-axis current and stator q-axis current.

The present invention belongs to the field of AC servo systems and discloses a method and system for online identification of the rotor time constant of a sensorless induction motor based on a complex coefficient flux observer. The method comprises: estimating the rotor flux using a complex coefficient rotor flux estimator; injecting a biased sinusoidal excitation into the d-axis to obtain the rotor flux and filtered stator current along the dq axes through park transformation; online identification of the rotor time constant using a designed rotor time constant estimator based on a sliding mode observer; and estimating the stator frequency and rotor position using a phase-locked loop. The present invention decouples rotor time constant identification from rotor speed estimation, enabling parallel estimation of the two. The designed rotor flux estimator effectively suppresses DC bias and higher harmonics in back electromotive force. Compared to the traditional least squares method, the designed rotor time constant estimator based on a sliding mode observer improves the robustness of the estimation algorithm while ensuring convergence speed.

The invention relates to the technical field of motor control, and discloses an induction motor rotor time constant adaptive control method, system and device, and the method comprises the steps: obtaining the current operation condition of a motor; determining a current angle threshold according to the current operation condition; dividing the running state of the motor into a first state and a second state based on a given current angle and a current angle threshold value of the motor; according to the divided operation states, a corresponding rotor time constant control strategy is executed so as to carry out indirect vector control of the induction motor, in the first state, a reactive power-based model reference adaptive algorithm is started, and a first rotor time constant is identified and output online; and in the second state, forbidding a reactive power-based model reference adaptive algorithm, and generating a second rotor time constant based on the first rotor time constant locked in the first state, thereby realizing reliable and accurate application of the reactive power MRAS scheme in a full working condition range.

This application provides an adaptive field weakening control method and apparatus under sensorless conditions. The method includes: planning reference values ​​for excitation current and torque current of an induction motor in a high-speed field weakening region; modifying the voltage flux linkage model in the MRAS speed observer and compensating the rotor time constant in the current flux linkage model to improve the accuracy of speed observation; performing adaptive complex vector current decoupling on the reference values ​​for excitation current, torque current, actual excitation current, and actual torque current to obtain reference values ​​for excitation voltage and torque voltage of the induction motor; performing flux linkage tracking on the reference values ​​for excitation voltage and torque voltage to obtain corresponding pulse width modulation (PWM) waves; and using the PWM waves to drive an inverter to achieve adaptive field weakening control of the motor. This application enables adaptive field weakening control of the induction motor even when it is operating at high speed.

The application provides a kind of asynchronous motor vector control method based on Kalman filtering, comprising the following operations: determining the initial value of the accurate estimation value of target torque current, target flux current and rotor time constant of the vector control of asynchronous motor;The following steps are cyclically executed: real-time acquisition of the voltage, current and speed of asynchronous motor;The real-time value of the stator torque current, stator flux current, stator torque voltage and stator flux voltage of asynchronous motor is calculated;Determine the rotor time constant identification measurement value based on the adaptive rate of the rotor time constant of asynchronous motor;Determine the rough estimation value of rotor time constant and Kalman filtering gain at the current time;Determine the accurate estimation value of rotor time constant at the current time;The vector control of asynchronous motor is based on the accurate estimation value of rotor time constant at the current time, target torque current, target flux current.The method of the application can effectively reduce the fluctuation of rotor time constant identification result while ensuring the identification accuracy.

The invention discloses an asynchronous motor parameter calibration method, device and equipment and a computer readable storage medium. According to the method, magnetic field orientation control is carried out according to a preset rotor time constant; monitoring the actual output torque of the asynchronous motor under each current combination, wherein different current combinations comprise the same M-axis current and different T-axis current; if it is determined that the T-axis current and the actual output torque are in a direct proportion relation based on the monitoring result, determining a rotor time constant calibration value according to a preset rotor time constant; respectively substituting the current combinations and preset equivalent inductance into a torque formula to obtain theoretical output torque corresponding to each group of current combinations; if the difference value between the theoretical output torque corresponding to each current combination and the actual output torque is smaller than the difference threshold value, the equivalent inductance calibration value is determined according to the preset equivalent inductance, through the method, the theoretical output torque and the actual output torque are made to be consistent, multiple other parameters do not need to be calibrated, and the test amount is reduced.

The application relates to the field of asynchronous motor control, in particular to a method for calculating the rotor time constant of an asynchronous motor driven by a frequency converter, which comprises the following steps: during the operation of the asynchronous motor, the three-phase voltage value and the three-phase current value of the asynchronous motor are sampled, and a voltage-current initial model is established according to the sampling results. The voltage equation of the asynchronous motor and the indirect magnetic field oriented vector control equation are used to perform Clark transformation on the voltage-current initial model, so that an adjustable model is obtained, the adjustable model is a model containing the rotor time constant and not containing the stator resistance; the error between the voltage-current initial model and the adjustable model is calculated, the error is adjusted by using proportional integral, and the rotor time constant of the asynchronous motor is obtained. The obtained result has better real-time effectiveness, avoids the precision error caused by factors such as temperature fluctuation and voltage fluctuation generated during the operation of the motor, and is also effective in the working scene of low-speed light load of the asynchronous motor.

The invention discloses an asynchronous motor torque current distribution method and system, and the method comprises the steps: receiving a target torque Te, and obtaining a steady-state excitation current Id (s) corresponding to the target torque Te; obtaining a rotor time constant Tr and an adjustable gain coefficient K, and carrying out dynamic compensation on the steady-state excitation current Id (s) based on the rotor time constant Tr and the adjustable gain coefficient K to generate a dynamic excitation current, and calculating a target torque current iq in real time according to the dynamic excitation current and the target torque Te; and inputting the dynamic excitation current and the target torque current iq into a current loop controller, and generating a PWM (Pulse Width Modulation) driving signal to control a power inverter. According to the method and the system, the speed of rotor flux linkage excitation is improved through dynamic compensation, the response speed of the torque of the asynchronous motor is further improved, and meanwhile, it can be ensured that the motor works at an expected working point under the steady-state working condition.

The application relates to the technical field of motor control, and discloses an induction motor rotor time constant adaptive control method, system and equipment, wherein the method comprises the following steps: determining a rotor time constant estimation value based on a reactive power deviation of a model reference adaptive system; determining a rotor resistance estimation value according to the rotor time constant estimation value and a real-time acquired rotor inductance parameter value; performing low-pass filtering on the rotor resistance estimation value to generate a filtered value; updating a rotor time constant feedforward value based on the rotor inductance parameter value and the filtered value; and optimizing a convergence process of the rotor time constant estimation value based on the rotor time constant feedforward value to perform indirect vector control of the induction motor. The method has the beneficial effect of improving the convergence speed and robustness of rotor time constant adaptive identification.