528 results about "Counter-electromotive force" patented technology

The invention relates to the field of intelligent control of electromagnetic appliances, and provides a control method and system for online fault diagnosis of a magnetic latching relay, and the method comprises the steps: responding to an external control instruction, collecting real-time bus voltage and real-time environment temperature data, constructing environment state characteristics through a magnetothermal coupling algorithm, and generating an initial PWM drive duty ratio; pulse modulation voltage is loaded, a current sampling sequence is collected, a current change rate sequence is obtained through moving average filtering and electromechanical coupling decoupling, extreme value searching is executed to extract counter electromotive force distortion characteristics, and a dynamic current sequential sequence is generated; a fusion input tensor is constructed, armature state probability distribution is output through a gating circulation unit, and a real-time energy compensation instruction is generated in a displacement interval before closing; and according to the real-time energy compensation instruction, respectively generating an enhanced driving waveform, a delayed driving waveform or a vibration driving waveform. According to the method, multi-mode physical characteristic perception and depth time sequence deduction are fused, and online fault diagnosis and active intervention closed loop of the magnetic latching relay are realized.

The invention provides a control method and system of a permanent magnet synchronous motor, computer equipment and a medium, and belongs to the field of motor control, and the method comprises the steps: obtaining stator current and voltage signals of the permanent magnet synchronous motor; constructing and operating a second-order sliding mode observer to output a stator current observation value; based on the current observation error and the change rate thereof, constructing a mixed sliding mode surface containing a linear term and a nonsingular terminal term, and designing a sliding mode control law; the control law is fed back to an observer to correct the observation process, and meanwhile two-phase observation counter electromotive force which is free of buffeting and does not need low-pass filtering is directly exported; closed-loop demodulation is carried out on the back electromotive force through a phase-locked loop, estimated values of the rotor position and the rotating speed are extracted, and finally position-sensorless vector control of the permanent magnet synchronous motor is achieved. According to the method, the buffeting phenomenon of a traditional sliding-mode observer is inhibited, a low-pass filter is avoided, phase lag is eliminated, and the estimation precision and the dynamic response performance of the system are improved.

The invention discloses a humanoid robot joint motor control method with model prediction control, and relates to the technical field of robot motion control. The method is used for solving the problems of control instruction infeasibility and model disturbance caused by voltage saturation during high-speed motion. An error state space model of a joint motor system is established, and non-linear terms such as gravity are used as nominal feed-forward quantities for stripping; then, the rotating speed of the motor and the bus voltage of the driver are collected in real time, the back electromotive force is calculated, and the voltage margin is mapped into a dynamic torque physical limit value at the current moment; and meanwhile, estimating an unmodeled lumped disturbance value of the model by using an extended state observer. And finally, taking the dynamic limit as a real-time inequality constraint, introducing a disturbance value correction prediction equation, constructing and solving a quadratic programming problem, extracting an optimal compensation torque, superposing the optimal compensation torque with an inverse dynamic feedforward torque, and converting the superposed torque into a current signal to drive a motor, thereby realizing high-dynamic and high-precision robust control under the physical boundary constraint.

An electrically powered aircraft is configured to check the health of its motors by determining a flux linkage associated with each of the motors. The flux linkage may be determined by measuring the back-EMF of stator coils of the motor. The flux linkage may be measured while the motor is not powered or may be estimated when the motor is in use. The flux linkage of a motor may be compared to a corresponding threshold value to assess whether the magnet(s) of the motor have degraded to a point at which they pose safety concerns. The flux linkage values may also be used to project when the motor needs to be maintained and / or replaced. The flux linkage value of a motor may be displayed, along with historical flux linkage values for that motor, to show a magnitude of demagnetization of the magnet(s) of the motor.

The invention discloses a pumping unit disc type permanent magnet motor multi-objective parameter optimization method, which relates to the technical field of motor design and optimization, and comprises the following steps: pre-establishing a multi-physical field coupling simulation model, constructing a disc type permanent magnet motor electromagnetic and thermal performance simulation model based on Motor-CAD and Maxwell software, and completing no-load, load and thermal performance tests of the motor. According to the method, the multi-physical field coupling simulation model is established in advance, so that comprehensive coupling analysis of electromagnetic and thermal performance of the disc type permanent magnet motor is realized, and high-precision data support is provided for multi-objective optimization; key structure parameters such as air gap length, slot opening width and the like are scientifically selected as optimization objects, maximization of motor efficiency and minimization of cogging torque are taken as core targets, and meanwhile, constraint requirements of output torque, back electromotive force and structure size are strictly adherent to each other, so that the pain point that multiple performances are difficult to consider at the same time in traditional optimization is effectively solved.

The invention discloses a dual three-phase permanent magnet synchronous motor harmonic suppression method based on virtual back electromotive force identification, and the method comprises the following steps: S1, building a driving system model of a DTP-PMSM; s2, constructing a harmonic model of the DTP-PMSM, analytically decomposing the nonlinear characteristic and the non-sinusoidal counter electromotive force of the inverter into dq and dqz subspaces, introducing the concept of virtual harmonic counter electromotive force, and unifying the nonlinearity of the inverter, the space harmonic counter electromotive force and cross coupling terms related to harmonic current into a single expression form; and S3, developing an identification principle based on current mapping, including amplitude and phase estimation, gain design and delay compensation, so as to estimate the amplitude and phase deviation of the virtual harmonic back electromotive force on line to realize harmonic suppression and avoid a complex algorithm and a large amount of parameter adjustment. According to the method, the operation effect is good in a wide rotating speed range, and meanwhile complex algorithms and a large amount of parameter adjustment are avoided.

The invention discloses an energy-saving operation control method and system for a permanent magnet direct current pump motor, and relates to the technical field of motor control, and the method comprises the steps: collecting a first drive current signal and a back electromotive force signal of the permanent magnet direct current pump motor; if a periodic peak and an electrical angle concentration phenomenon exist in the first driving current signal, performing quality evaluation on the back electromotive force signal to obtain back electromotive force credibility; if the back electromotive force credibility is greater than a preset credibility threshold value, applying operation parameter disturbance to the permanent magnet direct current pump motor; acquiring a second driving current signal of the permanent magnet direct current pump motor; performing disturbance response feature extraction on the permanent magnet direct current pump motor to obtain disturbance response features; identifying a disturbance source; and adjusting the operation strategy of the permanent magnet direct current pump motor to control the motor to operate. According to the method, the disturbance source can be recognized by combining the operation parameter disturbance and the disturbance response characteristics, the operation strategy is adjusted, motor operation control is achieved, and accuracy and reliability are improved.

The utility model discloses a motor and a compressor, the compressor comprises a motor, and the motor comprises a rotor, a permanent magnet and a stator. The rotor is provided with a plurality of first through holes arranged at intervals in the circumferential direction of the rotor and a plurality of magnet grooves arranged at intervals in the circumferential direction of the rotor, the first through holes and the magnet grooves are arranged in a penetrating mode in the axis direction of the rotor, and the first through holes extend by a preset length in the circumferential direction of the rotor. The magnet grooves are formed in the sides, close to the outer circumferential face of the rotor, of the first through holes and communicate with the first through holes, all the magnet grooves extend in the radial direction of the rotor, the two ends, in the circumferential direction of the rotor, of one first through hole communicate with one magnet groove correspondingly, and the two magnet grooves communicating with the same first through hole are symmetrically formed along the center line of the first through hole. The multiple permanent magnets are embedded in the multiple magnet grooves in a one-to-one correspondence mode. The stator is provided with a second through hole, and the stator sleeves the periphery of the rotor through the second through hole. The problem of poor back electromotive force sine of the motor in the prior art is solved.

The invention discloses an SMO-EKF brushless direct current motor position-free control method based on SBA-GWO double-layer optimization, SMO adopts sliding mode surface gradient-rotating speed double-factor segmented gain, and an improved SBA-GWO algorithm is combined with a global exploration mechanism of a stingless bee algorithm and a group cooperation characteristic of a grey wolf optimization algorithm. An elite initialization strategy and a dynamic search mode switching mechanism based on a grey wolf level are introduced, and an SBA-GWO algorithm is adopted for parameter optimization: in the first layer, SMO counter electromotive force THD is taken as fitness, and optimal gain is searched; in the second layer, the EKF estimation error quadratic sum is used as the fitness, and the Q / R adaptive residual noise time-varying property is optimized. And constructing an SMO-EKF cooperative control closed loop according to the optimized parameters to realize brushless direct current motor position-free control. Compared with the prior art, in the BLDC full-rotating-speed-domain position-free control, the dynamic response speed and the steady-state buffeting suppression effect are both considered, the robustness and the engineering realizability are remarkably improved, a physical sensor is not needed, and the engineering cost is low.

The invention discloses a motor permanent magnet health state online evaluation and residual life prediction method and system, and belongs to the technical field of motor state monitoring and fault prediction. The method comprises the following steps: state monitoring and signal acquisition working condition judgment; a back electromotive force signal and a d-axis injection optimization high-frequency signal are collected; performing FFT analysis, calculating THD, and identifying d-axis inductance Ld on line; fTHD and delta Ld are calculated; carrying out normalization on the characteristic quantity FTHD and the delta Ld, and carrying out cross validation; under the balance of the three-phase voltage, the health index HImagnet of the permanent magnet is calculated; and fitting the descending trend of the HImagnet, and predicting the remaining useful life RUL. According to the method, the evaluation precision and robustness can be remarkably improved by fusing the two strongly correlated and complementary characteristic quantities of the back electromotive force harmonic distortion FTHD and the d-axis inductance variation delta Ld, real-time early warning of the demagnetization fault of the permanent magnet is realized, and trend prediction of the residual life is realized.

The invention discloses a brushless motor rotor angle determination method and device, equipment and a storage medium. The method comprises the following steps: synchronously acquiring original angle data of a Hall sensor, an incremental encoder and a back electromotive force observation module; respectively determining confidence coefficients of the Hall sensor, the incremental encoder and the back electromotive force observation module according to the rotating speed of the rotor, and performing weighted fusion on the original angle data of the Hall sensor, the incremental encoder and the back electromotive force observation module to obtain an initial fusion angle; based on the motor temperature, the motor phase current and the rotor speed, calculating a temperature drift compensation angle through a segmented temperature drift coupling model, and compensating the initial fusion angle according to the temperature drift compensation angle to obtain a temperature drift compensated angle; and inputting the temperature drift compensated angle into an extended Kalman filter for state estimation and filtering to obtain a rotor angle estimation value at the current moment. By means of the method, high-precision real-time calculation of the rotor angle within the wide temperature range and the full rotating speed range can be achieved.

One aspect of the present disclosure provides an electric work machine including a brushless motor, a drive circuit, and a control circuit. The control circuit executes a driving operation, a braking operation, and a switching operation. In the driving operation, the brushless motor is rotated based on a back-EMF of the brushless motor. In the braking operation, a switch pair of six switches in the drive circuit is turned on, and the other four switches are turned off. The switching operation is performed during the braking operation. The switching operation includes switching the switch pair. In the switching operation, an off-target switch is turned off based on an electric current flowing through the off-target switch satisfying an off-requirement.

The invention relates to the technical field of life prediction of a permanent magnet in a permanent magnet synchronous motor, and discloses a multi-element segmented degradation modeling and life prediction method for the permanent magnet of the permanent magnet synchronous motor, which comprises the following steps of: firstly, selecting a back electromotive force fundamental frequency amplitude drop rate and a characteristic harmonic content rise rate as degradation characteristic quantities; respectively representing overall and local demagnetization behaviors of the permanent magnet; the method comprises the following steps: acquiring data through an accelerated degradation test, and establishing a segmented Wiener process model to describe stage characteristics of degradation; utilizing a t-Copula function to construct a joint distribution model of the multivariate degradation characteristic quantity; extrapolating model parameters under normal stress by combining an Arrhenius model and a segmentation point-temperature model; and life prediction is carried out by adopting Monte Carlo simulation, and the model precision is verified through an area ratio index and a cross validation method. According to the method, the degradation process of the permanent magnet can be comprehensively and accurately represented, high-precision life prediction is realized, and the method is suitable for reliability evaluation and preventive maintenance of a motor system.

The invention provides an intelligent reclosing method and device for a new energy power distribution network. The method comprises the steps that after the power distribution network breaks down, an energy storage power station is connected into the power distribution network, and back electromotive force active arc extinction control is carried out; after it is detected that the fault arc is extinguished, the energy storage power station serves as a main power supply to continuously supply power to a downstream load of the power distribution network; and if the operation mode is a network construction type operation mode, determining a delay duration based on a first reclosing starting threshold value, and carrying out a delay reclosing operation, and if the operation mode is a current limiting operation mode, determining a delay duration based on a second reclosing starting threshold value, and carrying out a delay reclosing operation. According to the method, the fault state can be accurately identified in the complex environment of high-proportion distributed new energy and energy storage access, secondary impact caused by blind switching-on is avoided, meanwhile, rapid recovery of power supply and safety and stability of the system are considered, and efficient, safe and economical operation of the new energy power distribution network is effectively guaranteed.

The invention discloses a permanent magnet wheel hub motor demagnetization fault diagnosis method considering multi-source signal fusion, belongs to the technical field of motor fault diagnosis, and aims to perform permanent magnet wheel hub motor demagnetization fault diagnosis by using a multi-source heterogeneous signal feature fusion method and solve the problem of dependence on additional sensors. The method mainly comprises the following steps: collecting multi-source signals such as current, back electromotive force and vibration under different conditions; performing symmetric point mode processing on the multi-source signal preliminarily, performing adaptive optimization and fusion on SDP parameters according to image fitness, and performing imaging processing again; the image database of the multi-source signals is used for fault diagnosis model training, and the diagnosis accuracy of each signal is obtained; a dynamic decision-making environment is established by integrating environmental conditions, image fitness and fault diagnosis accuracy, and a model is trained to realize optimal selection of multi-source heterogeneous signals under different conditions. According to the invention, through signal selection and fusion under different conditions, the accuracy and efficiency of motor fault diagnosis are improved.

The application provides a high-speed permanent magnet synchronous motor position sensorless control method and device, relates to the technical field of motor control, establishes a discretization extended counter electromotive force model of the permanent magnet synchronous motor, designs a complex vector decoupling current controller, directly designs a full-order state observer in a discrete domain, estimates rotor position and speed information, and improves real-time observation accuracy of the rotor position and speed. According to the motor speed, current and voltage information are fed back through a closed-loop control system, the current is optimally controlled in a region, and high-speed stable operation of the motor is realized.

According to one embodiment, a magnetic disk drive comprising, a magnetic disk, a magnetic head, a voice coil motor, and a controller. The controller includes a seek control section, a velocity calculation section, a back electromotive voltage estimation section, and a coil resistance estimation section.

The invention discloses a hybrid magnetic barrier design method for improving the average torque of a permanent magnet generator, the motor type is a double permanent magnet vernier motor, a stator and a rotor are provided with permanent magnets, the stator is wound with an armature winding, and an air gap magnetic field is composed of a stator permanent magnet magnetic field, a rotor permanent magnet magnetic field and an armature magnetic field. The average torque is derived from the interaction of an armature magnetic field and stator and rotor permanent magnetic fields. The stator is composed of six E-shaped module units in space, non-air-gap magnetic barriers exist between the module units, air-gap magnetic barriers are added to the two sides of a permanent magnet of the stator and the two sides of a permanent magnet of the rotor respectively, and the average torque is improved by improving the working wave content of an armature magnetic field and the working wave content of a permanent magnet magnetic field through the two types of magnetic barrier structures respectively. The hybrid magnetic barrier is simple in structure, the average torque of the permanent magnet vernier motor can be improved by more than 30%, and meanwhile, the sine property of no-load back electromotive force is improved.

The application discloses a method for controlling hybrid MMC sub-modules to clear DC short-circuit fault current. The method detects the real-time size of AC voltage, calculates the bridge arm voltage according to the principle of limiting AC current change and not affecting the speed of DC fault current clearing, and determines the number of improved sub-modules (sub-modules capable of providing counter electromotive force, such as full-bridge sub-modules) in each bridge arm according to the bridge arm voltage. Compared with the conventional method of directly locking all sub-modules to clear DC fault current, the application reduces the bridge arm current during the DC fault current clearing process, alleviates the overvoltage of the improved sub-modules, limits the influence on the speed of DC fault clearing, and improves the safety of the hybrid modular multilevel converter during the process of clearing DC fault current.

The application discloses a control circuit and a control method of a single-phase alternating current permanent magnet synchronous motor. The control circuit of the single-phase alternating current permanent magnet synchronous motor comprises a power supply module, the power supply module comprises a transformer, a first power supply unit and a second power supply unit, the transformer comprises a first secondary end and a second secondary end, the first power supply unit and the second power supply unit are electrically connected to the first secondary end and the second secondary end, a driving module comprises a first release end, a second release end, a first input end and a second input end, the first input end is electrically connected to the first power supply unit, the second input end is electrically connected to the second power supply unit, and the first release end and the second release end are electrically connected to the first secondary end and the second secondary end. In this way, by electrically connecting the first release end and the second release end of the driving module to the first secondary end and the second secondary end of the transformer, the energy of the counter electromotive force is absorbed or transmitted through the transformer, and potential interference or damage of the counter electromotive force to a reference ground circuit is avoided.

The utility model discloses an axial magnetic flux motor which comprises a rotor and a stator, the rotor comprises a plurality of magnets which are annularly arranged at intervals, the stator is arranged in the axial direction of the rotor, the stator comprises a stator iron core, the stator iron core comprises a plurality of iron core blocks which are annularly arranged at intervals, and air gaps are formed between the iron core blocks and the magnets. And the air gap is gradually widened from the center of the air gap to the two circumferential sides of the air gap. According to the technical scheme, the air gap between the iron core block and the magnet is designed to be gradually widened in the direction from the center of the iron core block to the two circumferential sides, so that the non-uniform air gap is formed, the back electromotive force waveform of the axial flux motor is improved, the harmonic content is reduced, the efficiency of the axial flux motor is improved, the cogging torque and the torque pulsation are reduced, and the service life of the axial flux motor is prolonged. And the performance is improved.

The utility model discloses a stator core and an axial flux motor, the stator core is suitable for being arranged in the axial direction of a rotor, the rotor comprises a magnet, the stator core comprises a plurality of iron core blocks which are annularly arranged at intervals, and the iron core blocks face the magnet and are provided with first areas, second areas and third areas which are sequentially arranged in the circumferential direction of the stator core. The second region protrudes relative to the first region and the third region, and the distance between the second region and the magnet is smaller than the distance between the first region and the magnet and smaller than the distance between the third region and the magnet in the axial direction of the stator core. According to the technical scheme, the second area is designed to be convex relative to the first area and the third area, and the distance between the second area and the magnet is smaller than the distance between the first area and the magnet and smaller than the distance between the third area and the magnet, so that the back electromotive force waveform of the axial flux motor can be optimized, the harmonic content is reduced, and the reliability of the motor is improved. The efficiency of the axial magnetic flux motor is improved, and the performance of the axial magnetic flux motor is improved.

The invention relates to the technical field of motor resonant frequency detection, in particular to a motor resonant frequency detection method and device, a chip and electronic equipment. Using the offset data to calibrate the anti-induced electromotive force signal of the motor to obtain a first anti-induced electromotive force signal, and obtaining the resonant frequency of the motor according to the detection result of the first anti-induced electromotive force signal; through the mode, the influence of the imbalance data of the anti-induced electromotive force signal on the detection of the resonant frequency is eliminated, and the detection accuracy of the motor resonant frequency is improved.

The invention relates to an aircraft system for suppressing movement of a structural flight element. The aircraft system includes a movable aircraft structure, a power source, a controller, a resistor, and a first transistor connected in series to the resistor. When the power source of the aircraft provides power, the controller controls the first transistor to prevent current from flowing through a terminal of the first transistor and through the resistor. Further, when the power supply of the aircraft does not provide power, the first transistor allows a current generated by a back electromotive force (EMF) voltage generated by movement of the movable aircraft structure to flow through a terminal of the first transistor and through the resistor.

The application provides a low-noise motor optimization method based on multi-parameter variable fusion, and the specific process is as follows: taking motor back electromotive force variation and minimum slot torque as an optimization objective function; taking motor rotor magnetic pole circular arc wrap angle as an optimization variable, and multiple iterations of the magnetic pole circular arc wrap angle are carried out in a set range, the magnetic pole circular arc wrap angle corresponding to the minimum objective function is taken as an optimal parameter of the motor, and low-noise motor optimization is realized; the magnetic pole circular arc wrap angle is proportional to the magnetic pole circular arc length. In the method, the magnetic pole circular arc wrap angle is taken as an optimization object, and the optimization design can be quickly and effectively completed, and the low-noise motor for vehicles can be developed.

The application discloses a variable-frequency-power-frequency automatic switching energy-saving system and method, and belongs to the technical field of motor control, which comprises the following steps: in the variable-frequency starting stage, a motor is driven to run at variable speed by a frequency converter; when the motor reaches full frequency, high power and stable operation, a control device controls the output voltage of the frequency converter to be synchronous with the grid voltage, and the switching to the power-frequency grid is completed when the phases are consistent; when the load decreases and needs to be reduced, the control device starts the frequency converter to make the output voltage of the frequency converter synchronous with the counter electromotive force of the motor in the power-frequency operation, then performs a back switching operation, the motor in rotation is smoothly connected by the frequency converter, and speed reduction control is implemented, and finally the variable-frequency speed regulation operation state is returned; the application realizes automatic selection of the optimal operation mode according to the actual load, avoids energy loss of the frequency converter in the high-speed area, and ensures that the impact on the motor and the grid in the switching process is minimum.

To provide a mathematical model that can be used for simulation, characterization-analysis, and control for a three-phase synchronous motor that generates iron loss in a stator, as well as a simulating device, characterization analysis device, or control device for a synchronous motor.SOLUTION: A mathematical model solves a problem regarding a stator reaction flux and rotor flux constituting a stator flux by providing an equivalent iron loss resistance so that iron losses occur in the stator reaction flux, while the iron losses does not occur in the rotor flux, and a voltage drop due to the equivalent iron loss resistance and a back electromotive force due to the stator reaction flux are roughly equal.SELECTED DRAWING: Figure 2

A control system for a motor drive configured to supply energy from a battery to an electric motor (1), said motor drive (22) comprising a set of power switches and configured to convert a continuous voltage (Vdc1) into an alternating voltage, the invention relates to a control system (1) for controlling a power switch (2) of a motor and further configured to supply a reverse generated first DC voltage (Vdc2) to a battery when the motor is operating as a generator, the control system comprising:-a driver unit (5) for controlling the power switch by an active short circuit (ASC) function to place phases of the motor in a short circuit configuration; and-an input of the driver unit (5) for enabling an ASC function; -an independent auxiliary inverter (71) providing a signal representative of the back electromotive force of the motor, in which the signal provided by the auxiliary inverter can be processed and linked to the input of the driver unit for activating the ASC function.

Methods and apparatus for driving a motor of a mechanical circulatory support device are provided. The method includes generating a pulse width modulated (PWM) drive signal, selectively filtering the PWM drive signal driving a first motor phase having a high state, sensing a back electro-motive force (back EMF) signal induced in a second motor phase not being driven by the PWM drive signal, determining a rotor position based on the back EMF signal, and modifying the PWM drive signal based on the rotor position.