65 results about "Stator inductance" patented technology

The invention discloses a sliding-mode observer based flux linkage observation method of an asynchronous motor. The flux linkage observation method is characterized by comprising the following steps of acquiring a continuous counter electromotive force e by Omega<r> through a high-order current sliding-mode observer according to a stator voltage vector v, a stator current vector i and a rotor electric angular speed, which are obtained through acquisition and operation, of the motor under a two-phase static coordinate AlphaBeta; building a state space expression of the asynchronous motor according to a relation between the counter electromotive force and rotor flux linkage; and building a flux linkage sliding mode observer according to the space expression. By the flux linkage observation method, the integral problem in flux linkage observation is solved, and relatively high robustness is generated for parameters such as rotor resistance, excitation inductance, rotor inductance and stator inductance; and meanwhile, the observer is simple in design, and engineering implementation is easy.

The invention provides an online identification method for a permanent magnet synchronous motor, and can realize the decoupling and the online identification of motor parameters, including stator inductance, rotor permanent magnet flux linkage and the like. The method comprises the following steps that: firstly, through a model prediction control method, a current prediction error formula is deduced, the stator inductance and the rotor flux linkage of the motor are further decoupled, mutual influences and mutual functions between motor parameters can be reduced, then, a Kalman filtering algorithm is used for carrying out online parameter identification on a discrete linear system, and a state vector is predicted and corrected. The filtered motor parameters can weaken the harmonic fluctuation of the motor due to external environment change in a running process so as to perform a significant meaning for eliminating the interference of external factors and improving motor control accuracy.

A method for starting an open-loop vector control, includes steps of: determining a stator inductance model of the machine; measuring the stator iductance in a plurality of directions; arranging the measured inductances in the model to form model parameters resulting in minimum error; checking the polarity of rotor magnetization to verify the direction thereof; initializing flux linkages of the open-loop vector control according to the model parameters and the direction of rotor magnetization; and starting the machine by the open-loop vector control method.

The invention provides a method for detecting the motor rotor position and the rotation speed based on an adaptive sliding mode observer and aims to detect the rotor position and the rotation speed ofa motor. The method comprises steps that S1, a state space expression of the sliding mode observer is constructed to obtain a switching signal of a stator current error; S2, a filter is added to remove the high frequency noise and obtain a smooth back EMF estimation signal; and S3, an FO-PLL phase locked loop is constructed, and the rotor position and the rotation speed are calculated; and S4, stator resistance and stator inductance parameters in the sliding mode observer are identified and updated through the improved particle swarm optimization algorithm. The method is advantaged in that the rotor position and the rotation speed of the brushless DC motor can be detected accurately and instantly.

The invention discloses an asynchronous motor rotor time constant online recognition method based on an improved reactive power model. According to the invention, a feed-forward for a motor stator frequency, subjected to the amplitude limiting treatment, is introduced in a conventional reactive power model. The method comprises the steps of sampling and obtaining the actual reactive power Q of a motor by an actual reactive power calculation unit; obtaining the stator inductance Ls of the motor by a stator inductance calculation unit; obtaining the reference value Isdref of the d-axis component of the stator current of the motor by an excitation controller; obtaining the theoretical reactive power Qref of the motor by a theoretical reactive power calculation unit; obtaining the reactive power deviation delta Q by a deviation calculation unit; obtaining a feed-forward value omega Q by an amplitude limiting unit; obtaining a correction value delta Tr for the rotor time constant Tr of the motor by a proportional-integral controller; and calculating the rotor time constant Tr of the motor by an arithmetic operation unit. The above method can be applied in the four-quadrant operation scenarios for the motor. By means of the method, the proportional-integral controller of the reactive power model is easy to set. At the same time, the similar rotor time constant convergence dynamic process can be obtained during the high-speed and low-speed operation process of the motor.

The invention discloses a motor parameter adaptive adjusting method, a device, a motion control system and an unmanned plane; the method comprises the following steps: executing a set motor start control according to a motor start order; obtaining the present rotating speed of the motor under the start control; obtaining the present time duration of the executed motor start control; when the present time duration reaches a set time threshold yet the present rotating speed cannot reach a set rotating speed, diagnosing the motor to have a start failure; measuring the motor stator inductance so as to obtain the stator inductance true value according to the diagnosis result of the start failure; correcting the stator inductance present value as the obtained true value.

The invention discloses an online identification method and an online identification device for stator resistance of a motor, and a motor control system. The online identification method comprises the steps of: injecting a preset current to a d-axis of a synchronous rotating dq axis system; acquiring a d-axis voltage and a d-axis current of the synchronous rotating dq axis system; carrying out high-pass filtering processing on the d-axis voltage and the d-axis current separately; and calculating the stator resistance of the motor according to the d-axis voltage and the d-axis current after high-pass filtering processing as well as stator inductance of the motor. The online identification method can obtain accurate stator resistance, has the advantages of simple measurement and easy implementation, and can be applied to engineering practice.

The invention relates to a non-contact method for measuring the temperature of a pumping medium. The method comprises the steps of step I, immersing a rotor in a motor on the pump body in fluid and running; step II, during the operation of the motor, injecting high-frequency current in the non-breakover phase in real time, and detecting induced potential, detection current and frequency of the no-breakover phase and stator temperature; step III, obtaining the resistance of a stator coil by combining the induced potential, the current, the frequency and the stator inductance, namely the temperature of the stator coil is obtained; step V, obtaining the medium temperature according to the linear relation between the temperature of the stator coil and the medium temperature. The non-contact method for measuring the temperature of the pumping medium has the beneficial effects that the reactance change rate of a winding is detected by a high-frequency pulse current injection method, the change of liquid temperature has no influence on the inductance of a winding, the resistance change rate of the winding can be directly presented by the reactance change rate of the winding, the resistance change rate is only influenced by the winding temperature, and the influencing factor is single.

The invention discloses a self-tuning method and system for permanent magnet synchronous motor current loop PI regulator parameter, and the method comprises the steps: simplifying a current feedback link into unit negative feedback without delay, simplifying a PWM inverter link, and obtaining a simplified current loop structure comprising a PI regulator and a stator winding; establishing a simplified current loop open-loop transfer function based on the simplified current loop structure; performing zero-pole cancellation on the PI regulator transfer function and the stator winding transfer function to obtain a current loop closed-loop transfer function in a first-order inertia link form; and for the condition that the stator resistance and the stator inductance change along with the running state of the motor, identifying the optimally estimated stator resistance and inductance, and adjusting the parameters of the PI regulator in real time. According to the invention, the self-adaptivesetting of the current loop PI regulator parameters is realized, and the problem that the PI regulator parameters are not matched with the actual operation conditions of the motor is solved.

A method for determining rotor position comprising sending a signal to a stator, receiving a first signal indicative of a first estimated stator inductance, and receiving a second signal indicative of a second estimated stator inductance. The method further includes, calculating a first rotor position angle using a function including the first estimated stator inductance and the second estimated stator inductance.

The invention provides a synchronous motor self-tuning method suitable for a vertical elevator. The synchronous motor self-tuning method comprises a stator resistance tuning step, a stator inductance tuning step and an initial angle tuning step. The synchronous motor self-tuning method is applied to an elevator control system, is suitable for various power motors, is simple to operate and high in efficiency and can finish parameter learning in one step. A lift car does not need to be hoisted in the self-tuning process, and only once parameter self-tuning is carried out in installation.

The invention discloses an improved MRAS control method based on a limited memory least square method. A limited memory least square method identification module is configured in front of an adjustable model of a traditional MRAS; online identification is carried out on PMSM nonlinear parameters, the characteristics of old data elimination and updating of a limited memory least square method identification algorithm are utilized, the defects of data saturation and identification result direction deviation in the identification process are effectively avoided, and the identification accuracy and rapidity are improved. And the stator resistance, the stator inductance and the rotor flux linkage of the PMSM obtained by identification are input into the MRAS adjustable model in real time, and the nonlinear quantity of the adjustable model is updated in real time, so that the stator current vector error is more accurate, and the accuracy of self-adaptive rotating speed estimation is furtherimproved. The method has the advantages of being high in control accuracy, good in dynamic performance, high in robustness, low in cost, simple in control algorithm, high in estimation speed and precision of the rotating speed and the position and the like.

The invention discloses a modeling method of a twelve-phase permanent magnet synchronous motor, wherein a harmonic winding is considered, and the method comprises the following steps: 1) constructinga twelve-phase permanent magnet synchronous motor inductance coefficient matrix, and establishing an analytic expression considering the self-inductance and mutual inductance of each phase stator winding of the harmonic winding according to a winding function; 2) establishing an analytic expression of fundamental wave flux linkage and harmonic wave flux linkage generated by the permanent magnet in each phase of stator winding; and 3) determining the optimal coefficients of the stator inductance and the permanent magnet flux linkage by using a Matlab curve fitting function. According to the method, the harmonic winding having significant influence on the motor characteristics is considered in the modeling process of the twelve-phase permanent magnet synchronous motor, which has important theoretical significance for improving the accuracy of analysis and control of the permanent magnet synchronous motor.

The invention provides a method for identifying a permanent magnet flux linkage of a non-salient pole permanent magnet synchronous motor, an identification device and a computer readable storage medium. The method for identifying the permanent magnet flux linkage of the non-salient pole permanent magnet synchronous motor comprises the following steps of acquiring a phase voltage and a phase current of the non-salient pole permanent magnet synchronous motor on an <alpha><beta> coordinate system; and according to the phase voltage, the phase current and a stator inductance L<s> of the non-salient pole permanent magnet synchronous motor, calculating the permanent magnet flux linkage <psi><f>. By adoption of the permanent magnet flux linkage identification method, the permanent magnet flux linkage is subjected to online identification without influencing the normal operation of the motor, and the identification precision is improved, and therefore, reasonability of design of a motor control system is ensured, and the control effect of the non-salient pole permanent magnet synchronous motor is improved.

The invention provides a rotor flux-based rotating speed calculation algorithm for improving the orientation accuracy of a rotor. The rotating speed calculation algorithm provided by the invention comprises the following steps of (1) calculating a product of stator voltage, stator resistance and stator current and then making a difference from the product of stator inductance Ls and stator inductance is to obtain a rotor flux calculated value in a two-phase static coordinate; (2) substituting the real-time adjusted cutoff frequency into a compensation amount calculation formula and taking theobtained numerical value as a compensated flux value; (3) calculating a current rotor flux value under current exciting current according to the rotor flux calculated value and the compensated flux value; (4) calculating an adjustable rotor flux value according to alpha and beta-axis components of the rotor flux, the stator resistance, rotor inductance and mutual inductance, the stator inductanceand a differential operator; and (5) calculating a rotating speed of the motor according to the current rotor flux value and the adjustable rotor flux value.

The invention relates to an online identification method for inductance parameters of an asynchronous motor. The method comprises the steps of 1) performing rotor magnetic field accurate orientation based on load angle compensation correction according to current and voltage signals under d-q synchronous rotation coordinates; 2) performing closed-loop adjustment on a d-axis flux linkage of a stator under the condition of the accurate orientation of a rotor magnetic field; 3) carrying out online identification on stator inductance parameters under the conditions of the accurate orientation of the rotor magnetic field and the closed-loop adjustment of the stator d-axis flux linkage; and 4) under the conditions of the rotor magnetic field accurate orientation and the stator d-axis flux linkage closed-loop adjustment, carrying out online identification on a magnetic flux leakage coefficient, and feeding back a result of online identification of the magnetic flux leakage coefficient to therotor magnetic field accurate orientation. Compared with the prior art, the method does not need to introduce a complex, tedious, time-consuming and resource-consuming algorithm, does not need specialhardware support, can achieve the quick and accurate online recognition of the stator inductance and the magnetic flux leakage coefficient, and guarantees the real-time accuracy of inductance parameters needed by a vector control system.

An alignment method for a radial magnetic suspension stator element of a gyroaccelerometer includes a turntable and a cross slide table. A stator tool is arranged on the turntable and connected with an inductance tester. An adjustment mechanism is arranged on the cross slide table. The adjustment mechanism is provided with a torque sensor. After adjusting a pitch angle, a yaw angle and a center height of a rotor tool, by passing a stator element through a rotor element, variation on inductance values of the stator element is measured through the inductance tester and an axial coincidence position is obtained according to the variation on inductance values of the stator element. By contacting a rotor element with coils of the stator element, a contact force is measured by the torque sensorand sent to an industrial personal computer for calculating a coaxial position. By the method, coincidence of the stator element to the rotor element in the axial position and coaxial alignment of theradial position of the stator element are achieved.

The invention discloses a permanent magnet synchronous motor parameter on-line identification method based on model reference self-adaption. An identification model is established according to a discretized Popov hyperstability principle, when a motor runs, an identification result is continuously corrected according to collected data such as voltage, current and rotating speed, and more accurate motor parameters such as stator inductance and rotor permanent magnet flux linkage are obtained, so the operation condition of the motor is monitored in real time, and the accuracy and stability of motor control are improved. The influence caused by motor parameter change and space harmonic generation is effectively avoided, and the robustness of a motor driving system is improved.

The invention relates to an improved dead-beat prediction current control method for a permanent magnet synchronous motor. The method comprises the following steps of firstly, establishing a new current updating mechanism to obtain new prediction current and voltage equations, then deriving a prediction current error formula according to the dead-beat prediction current control method, further decoupling stator inductance, decoupling rotor flux linkage by utilizing the voltage formula, and finally obtaining the dead-beat prediction current of the permanent magnet synchronous motor. Then, inductance and flux linkage parameters are subjected to online parameter identification based on a forgetting factor least square method, estimator errors are predicted and corrected, filtered stator inductance and rotor flux linkage can effectively restrain generation of current ripples and torque following deviation, power loss is reduced. The method is easy and convenient to operate, ideal in effectand suitable for popularization and application; the number of calculation times is effectively reduced, accuracy of parameter identification can be effectively improved, and a problem that the motorperformance is reduced due to continuous change of motor parameters in the operation process is solved.

The invention provides an inductance type rotation position sensor. According to the technical scheme, detection is realized based on the principle that stator inductance changes with angles when a rotor rotates, and a specific insulating material and a brand-new arrangement structure are adopted for low-temperature operation of the sensor. Specifically, a mechanical structure and an electrical structure are designed by adopting an inductance measurement method, so that the structure of the device can be remarkably simplified. Low-temperature-resistant insulating materials are adopted, and enough mechanical strength can be guaranteed through the enameled wire, the insulating sleeve and the paint dipping process. In the detection process, alternating current or alternating voltage can be applied to the sensor coil. After the generated alternating voltage and alternating current are measured, a low-frequency signal is output through the signal processing circuit, then a synthesized vector is obtained through Clark conversion, and the angle of the sensor is obtained by calculating the angle of the synthesized vector. The sensor has a good detection effect, the applicable temperature range of the sensor is remarkably widened, meanwhile, a complex system structure is not needed, and low product cost can be guaranteed.

The invention provides a permanent magnet synchronous motor static initial position estimation method and a stator inductance identification method. A rated positive pulse voltage and a rated negative pulse voltage are sequentially injected into windings of an AB phase, a BC phase and a CA phase of a motor, response current values of the phases under the rated positive pulse voltage and the rated negative pulse voltage are recorded, and current response difference values delta Iab, delta Ibc and delta Ica of the AB phase, the BC phase and the CA phase under a three-phase static coordinate system are calculated; performing Clark transformation on the current response difference values of all phases to obtain current response difference values delta I alpha and delta I beta under the alpha-beta axis two-phase static coordinate system; and calculating the initial position theta of the rotor based on the delta I alpha and the delta I beta. And calculating the stator inductance of the permanent magnet synchronous motor based on the initial position of the rotor obtained through calculation. Through coordinate transformation and solution, the rotor position is directly obtained through current pulse response, an intermediate conversion link is omitted, data loss can be reduced, and data precision is guaranteed.

The invention relates to a permanent magnet motor position-sensorless rotor position determining method and device. The method includes the following steps that: stator voltage, stator current, stator inductance and stator resistance are acquired; the flux linkage change rate of a permanent magnet motor is calculated according to the stator voltage, stator current, stator inductance and stator resistance; low-pass and high-pass filtering are performed on the flux linkage change rate, the flux linkage of the permanent magnet motor is obtained; and accurate flux linkage is obtained according to the flux linkage, a first preset parameter and a second preset parameter; and the rotor position angle of the permanent magnet motor is obtained according to the accurate flux linkage. According to the method and device, the low-pass and high-pass filtering link is adopted, so that errors caused by interference and direct-current components can be eliminated; the flux linkage is compensated through the first preset parameter and the second preset parameter, so that the problem of phase delay can be solved, and therefore, the obtained accurate flux linkage has high accuracy; and the accurate rotor position angle can be obtained according to the high-accuracy accurate flux linkage; and therefore, the accurate estimation of the rotor position angle can be realized, and the permanent magnet motor can be controlled precisely.