21 results about "Synchronous coordinates" patented technology

The invention discloses a pole piece die cutting defect online detection and sorting control method and system, particularly relates to the technical field of pole piece die cutting online detection and sorting control, and is used for solving the problems of uncertain event positioning and sorting errors caused by time base asynchronization, coordinate mapping drifting and late disorder under a multi-station dynamic beat condition. A double-anchor time base and an idempotent key are established, water line propulsion and out-of-order window playback are taken as an order basis under a unified time axis, online self-certification of same-layer coordinate transformation and time check and space check in a topological graph are matched, unified judgment is implemented at the merging moment, and two-section interlocking execution is performed. Therefore, under the multi-station dynamic rhythm, a determined and reviewable sheet-level corresponding relation is established between the detection event and the stroke frequency, the mold cavity and the discharging port, the consistency of sorting decisions is still kept in the face of late, disorder and state transition, and the risk of wrong sorting and missing sorting is reduced.

The invention discloses a dual-channel electric drive multiplexing type vehicle-mounted charging system unbalanced current suppression method, which comprises the following steps of: firstly, popularizing and applying a positive and negative sequence separation method for decoupling a dual-synchronous coordinate system to a dual-channel six-phase motor, and calculating positive and negative sequence components of a dq axis of a dual-channel system under a current unbalanced working condition; utilizing Park and VSD transformation to map the data to an alpha beta xy0102 sub-plane; secondly, setting a positive-sequence current given value and a negative-sequence current given value to be 0 by using a six-phase current distribution method for minimizing electromagnetic torque; then, independent PI control is carried out on each sub-plane; and finally, correspondingly adding the output quantities of the positive sequence current and the negative sequence current of each sub-plane, returning to a natural coordinate system through TVSD-1, and then outputting SPWM, thereby realizing a three-phase charging working condition. According to the method, the suppression of the negative-sequence current can be realized, the sine degree of the power grid current is improved, the torque ripple is suppressed, and the system safety is guaranteed.

The embodiment of the invention relates to the technical field of wind turbine generator control, and provides a dynamic compensation control method and system for a rotor voltage of a wind turbine generator, and the method comprises the steps: decomposing a power grid voltage and a rotor current into a positive-sequence component and a negative-sequence component in real time through constructing a self-adaptive decoupling control architecture based on a dual-synchronous coordinate system; a positive-sequence channel is responsible for accurately tracking active and reactive power instructions and guaranteeing a power generation task, and a negative-sequence channel is responsible for accurately tracking a positive-sequence channel and a negative-sequence channel; the negative sequence channel aims at eliminating negative sequence current and suppresses second harmonic pulsation; a dynamic compensation gain mechanism is further introduced, the fault severity is evaluated by quantifying the unbalance degree of a power grid in real time, and the intensity of negative sequence compensation is adaptively adjusted, so that the control strategy can maximally suppress pulsation when a slight fault occurs, and the safety of the converter is preferentially guaranteed and the overcurrent risk is avoided when a serious fault occurs.

According to the present invention, an estimator: sets, to Ts(=2×Tc=Th), a control period in which a process pertaining to a sensorless vector control is executed; applies a high frequency voltage of a period Th corresponding to a frequency other than an audible range on a γ axis of a γδ quasi-synchronous coordinate system in synchronization with Ts and Tc; detects, in a period Tc, a stator current including a fundamental driving frequency component and a high frequency component; generates at least one of a γ axis element signal cγ or a δ-axis element signal sδ by temporal subtraction between two recent stator current detection values for each period Ts on a γδ quasi-synchronous coordinate system; uses the generated axis element signal and generates, for each period Ts, a positive correlation signal pc having positive correlation with the difference between a rotor phase and a γ-axis phase; signal-processes the positive correlation pc so that the positive correlation pc becomes 0; and generates an estimation value of the phase or speed of a rotor.

The invention discloses a force closed-loop sliding-mode control method for an electronic mechanical braking system, and relates to the technical field of an EMB system of an electric vehicle, and the method comprises the steps: building a motor model according to the basic characteristics of a motor under a rotor synchronous coordinate system; and based on a novel power exponent reaching law, force closed-loop sliding mode control of the electronic mechanical braking system is constructed according to a motor model and a relational expression between clamping force and friction plate displacement. By designing the force closed-loop sliding mode control power exponent reaching law, the clamping force is controlled in real time, and the problems that under the condition that other coefficients of an existing sliding mode control reaching law are the same, the reaching speed of a state variable to a sliding mode surface s = 0 is low, and buffeting can be generated are solved.

The invention relates to a position sensorless control method, device and system of a permanent magnet synchronous motor. According to the method, an inductance differential term under a motor voltage equation in a synchronous coordinate system is subjected to approximate processing, a novel counter electromotive force is defined, a full-order observer based on the novel counter electromotive force is designed for position observation, global convergence of the full-order observer is proved, and therefore it is guaranteed that the full-order observer is stably started at the zero speed. Through error analysis, a current control strategy is designed to avoid the influence of a resistance error on position observation. Compared with a traditional observer, the full-order observer based on the novel back electromotive force has the advantages that no d-axis inductance exists in a state equation, and therefore the influence of the d-axis inductance on position observation can be ignored. Compared with an existing high-frequency signal injection method technology, the method can achieve sensorless control and on-load inversion at zero low speed without signal injection, avoids high-frequency noise generation and extra energy loss, and has a wide industrial application prospect.

The invention provides a control method and system based on a decoupling bisynchronous coordinate system current controller. The method comprises the following steps: acquiring a current value when a current power grid has a fault, and performing rotation transformation on the current value to obtain a positive sequence coordinate system current under a positive sequence coordinate system and a negative sequence coordinate system current under a negative sequence coordinate system; determining a dq-axis positive and negative sequence decoupling item of the positive sequence current controller, active and reactive decoupling feedforward items and a positive sequence voltage value required to be output by the positive sequence current controller; performing double inverse rotation transformation on the dq-axis positive and negative sequence decoupling item to obtain a positive sequence component under a negative sequence coordinate system; determining a negative sequence voltage value required to be output by the negative sequence current controller; and determining a control voltage reference value corresponding to the current value when the current power grid has a fault, and driving a power unit of the current controller to act based on the control voltage reference value. According to the technical scheme provided by the invention, the response speed and the control precision of the current controller under the power grid fault condition are improved.

The application discloses a kind of based on the power distribution control method of multi-port motor driver of double synchronous coordinate system, first decoupling modeling is carried out to multi-port motor driver, according to its output voltage, it is equivalent to two independent two-level sub-driver units, to decouple the power flow path of first and second DC source;Establish the port power relationship between multi-port motor driver and sub-driver unit;Then according to the first DC source port reference power, directly adjust the shaft reference voltage of two sub-driver units;Again based on interleaved clamping, constrain the switching times of each sub-driver unit, obtain the correlation expression of shaft reference voltage by constraint condition, and then obtain complete shaft reference voltage;After coordinate transformation and zero sequence voltage injection, generate the final three-phase modulation signal;Finally, the three-phase modulation signal is compared with triangular carrier, to generate drive signal, to control each bridge arm switch tube.

The application discloses a method and system for online detection and sorting control of pole piece die cutting defects, and particularly relates to the technical field of online detection and sorting control of pole piece die cutting, and is used for solving the problems of event landing uncertainty and sorting error caused by time base asynchronization, coordinate mapping drift and late disorder under the condition of multi-station dynamic rhythm. Through the establishment of double-anchor time base and idempotent key, on the basis of water line promotion and disorder window playback as the order under the unified time axis, combined with online self-proving of coordinate transformation of the same layer and time calibration and space calibration in the topological graph, unified decision is implemented at the merging moment and two-section interlocking is executed, so that the pole piece detection event is established in a determined and reviewable piece-level corresponding relationship with the punching frequency, die cavity and discharge port under the condition of multi-station dynamic rhythm, and the consistency of sorting decision is maintained and the risk of misclassification and missed classification is reduced in the face of late arrival, disorder and state transition.

A speed sensorless control method suitable for a wind power permanent magnet synchronous generator belongs to the technical field of speed sensorless, and comprises the following steps: S1, constructing a single synchronous coordinate system phase locking model, and performing phase locking on power grid voltage through a d-axis component; s2, constructing a dq-axis oriented rotor position orientation regulator, and dynamically adjusting a phase angle under a load condition through a phase angle of no-load phase locking; and S3, constructing a megawatt permanent magnet synchronous wind generator speed sensorless vector control model. Real-time phase locking of generator stator voltage is realized through a software phase-locked loop model, a stator voltage vector angle is used as feedforward input, and a position orientation regulator of a rotor d-axis or q-axis is established according to a model reference adaptive principle, so that accurate orientation of a vector control coordinate system is realized; the speed sensorless control method not only has good torque and rotating speed dynamic and static following capability, but also is simple in engineering application and strong in system robustness.

Based on Ts (=2×Tc=Th), a control cycle for performing sensor-less vector control-related process, an estimator applies synchronously with Ts and Tc, high-frequency voltage having cycle Th corresponding to frequency outside audible range on γ-axis of γδ semi-synchronous coordinate system, detects stator current including basic drive frequency component and high-frequency component at cycle Tc, time-differentiates two most recent detected values of stator current on γδ semi-synchronous coordinate system per cycle Ts, to generate either or both of γ-axis component signal cγ and δ-axis component signal sδ, generates positive correlation signal pc having positive correlation with deviation between the rotor phase and the γ-axis phase per cycle Ts by using the generated axis component signal, and performs signal processing of positive correlation signal pc such that positive correlation signal pc becomes zero, to generate estimated value of the phase or the speed of the rotor.

This invention discloses a method for identifying the admittance of a three-phase grid-connected inverter based on a complex-valued neural network, relating to the field of power electronics technology. The method includes: constructing a small-signal flow graph of the three-phase grid-connected inverter in a synchronous coordinate system; constructing a port admittance matrix at the steady-state operating point; determining the corresponding characteristic polynomial and factoring it to obtain a unified pole set; constructing the pole-residual expansion of the port admittance matrix based on the unified pole set; determining the transfer function of each element in the port admittance matrix; constructing a complex-valued neural network and its loss function; training the complex-valued neural network using the loss function; and inputting the operating condition information and frequency point of the grid connection point into the complex-valued neural network to obtain the port admittance under the current operating condition. This method has the technical advantages of low computational complexity, high identification efficiency, support for rapid identification under multiple operating conditions, and high physical interpretability of the fitting results.

The invention relates to the technical field of new energy vehicles, and discloses a cross-layer collaborative architecture-based vehicle intelligent network connection test system, which comprises the following steps of: establishing a tunnel longitudinal position system taking a semi-closed tunnel door opening reference surface as a space starting point, and mapping multi-source acquisition data to the tunnel longitudinal position system to construct a cross-layer state data set; extracting interference values such as enclosure surface reflection, illumination transition, positioning attenuation and communication attenuation according to the set, fusing to generate a composite distortion density, and calculating an interval midpoint and width of a preposed contraction high-risk interval according to the composite distortion density; maximizing the response change rate of the vehicle application layer in the high-risk interval by adopting a particle swarm algorithm so as to obtain an optimal test control instruction set; executing a test based on the instruction set, and remapping each layer of data to an interference synchronization coordinate system; and finally, calculating a trigger concentration point and a distortion concentration point of an application layer, quantifying a trigger offset to determine a core failure reason, and solidifying the core failure reason into a test template and an execution script.

The application discloses a compensation method for phase delay error of a brushless direct current motor, which comprises the following steps: collecting three-phase current data of the brushless direct current motor in real time; constructing an adaptive linear neuron filter based on a recursive least square method in a DSP to extract three-phase current fundamental waves; converting the three-phase current fundamental waves to a synchronous coordinate system through coordinate transformation to obtain d-axis current; outputting the difference between the d-axis current and 0 to a PI regulator, wherein the output of the PI regulator is a phase compensation angle; through adaptive compensation for several periods, the PI regulator tends to be stable, and finally the output compensation angle is the optimal phase compensation angle under the working condition. The method accelerates the convergence speed of a weight factor by means of the improved Adaline filter, improves the steady-state accuracy, and has the advantage of improving the operation efficiency of the brushless direct current motor.

The invention discloses a dual-synchronous coordinate system phase-locked loop optimization strategy which comprises a Clarke transformation unit, a Park transformation unit, an iPark transformation unit, a positive sequence decoupling network, a negative sequence decoupling network, a low-pass filter, a PI regulator and a frequency integration unit. When the amplitude of one-phase or two-phase voltage is zero, one-phase voltage with the amplitude not zero is selected, and a single-phase phase-locked loop lock is adopted for phase locking; and when the amplitudes of the three-phase voltages are not zero, Clarke conversion is carried out on the three-phase voltages, and the frequency is assigned to an integral quantity of a PI regulator of the three-phase phase-locked loop, so that the phase-locked loop of the double-synchronous coordinate system jumps out of a pseudo-steady state. Different coping strategies are determined to be adopted according to different voltage conditions, and the problem that the phase-locked loop of the double-synchronous coordinate system enters a pseudo-steady state is effectively prevented.

The invention discloses a synchronous coordinate system phase-locked loop based on performance excitation anti-saturation control. The synchronous coordinate system phase-locked loop is composed of a phase detector, a loop filter, an artificial amplitude limiter, an anti-saturation feedback loop, a voltage-controlled oscillator and a performance excitation loop. An artificial amplitude limiter is arranged between a loop filter and a voltage-controlled oscillator, so that the variation amplitude of a frequency estimator is limited, and frequency divergence caused by depth disturbance is inhibited. And meanwhile, an anti-saturation feedback loop is constructed by using a difference value between input and output of the amplitude limiter, the recovery process of an integration link is accelerated when saturation occurs, and the attraction domain of a closed-loop system is expanded. Besides, a tracking error formed by a phase estimation value of the phase-locked loop and an expected value is introduced into a performance excitation loop for adjusting the starting opportunity of anti-saturation compensation and improving the dynamic performance in different operation scenes. According to the scheme, the stable phase tracking capability can be kept in a complex electric energy environment, and the synchronization reliability of the converter is improved.

The invention discloses a moving object positioning method and device based on multi-modal sensor fusion, and belongs to the technical field of multi-sensor fusion and computer vision. In order to solve the problems that a single IMU has drift errors and a single visual system is influenced by illumination and shielding, high-frequency dynamic data of the IMU and low-frequency but high-precision visual information provided by a fixed camera are effectively combined through the steps of time synchronization, coordinate system calibration, extended Kalman filtering fusion, error optimization and the like. The system firstly performs interpolation alignment on the asynchronously acquired IMU and image data, and then unifies the IMU and image data to a world coordinate system; then, the state is predicted through an IMU by means of an EKF, drifting is corrected through image feature points, and finally high-precision and high-robustness three-dimensional positioning and attitude estimation are achieved. The method is suitable for medical ultrasonic scanning assistance, robot navigation, augmented reality, unmanned driving and other application scenes with limited GPS or complex environment, and has the advantages of high real-time performance, high precision, wide adaptability and the like.

The invention relates to the technical field of motor synchronous modulation, and discloses a torque ripple suppression salient pole synchronous motor synchronous modulation method and system, and the method comprises the steps: improving the scalar relation between the current harmonic amplitude of a motor and the switching angle of an inverter into a vector relation according to the electrical parameter information of the motor; a torque current harmonic balance equation is introduced, and difference analysis of influences of d-axis and q-axis currents of the synchronous coordinate system on torque pulsation is carried out; a weighting coefficient is introduced and a cost function is designed to transfer a current harmonic wave from a q axis to a d axis, so that the sinusoidal property of the phase current is kept and the torque ripple is effectively suppressed. By introducing a weighting coefficient, current harmonics on a q axis are transferred to a d axis, and effective suppression of torque pulsation is realized. And two-dimensional variables are converted into single variables, so that the complexity and dimensionality of solving the switching angle are reduced.

A method for estimating the rotor position and speed of a permanent magnet synchronous motor based on a Hall sensor comprises the following steps: 1) obtaining a series of discrete electrical angle values ​​according to the signal output by the Hall sensor installed on the stator of the permanent magnet synchronous motor; 2) fitting six continuous discrete electrical angle values ​​by the least squares algorithm to obtain continuous electrical angle information for coordinate transformation and as input of a sliding mode observer; 3) obtaining d-axis current value and q-axis current value by coordinate transformation of the sampled three-phase current value, and calculating the electromagnetic torque according to the electromagnetic torque equation in a synchronous coordinate system; 4) designing a sliding mode observer according to the mechanical motion equation of the motor to observe the electrical angular velocity and load torque of the rotor; 5) using the electrical angular velocity observed by S4 as feedback of the speed loop, and feeding the observed load torque value forward to the q-axis current loop. The present invention effectively estimates the rotor position and load torque, reduces the estimation errors of the position and speed, and enhances the robustness of the system.

A method for drivetrain load mitigation of grid-forming (GFM) doubly-fed induction generator (DFIG)-based wind turbine generator (WTG) based on phase angle feedforward, wherein: acquiring active power of a GFM DFIG-based WTG; calculating difference value between acquired active power of GFM DFIG-based WTG and active power reference value; inputting difference value into GFM control to obtain output signal; adding output signal and reference frequency value of virtual synchronous coordinate system to obtain frequency of virtual synchronous coordinate system; integrating the frequency to obtain output value; multiplying additional damping active power reference value of GFM DFIG-based WTG by control gain of phase angle feedforward control to obtain product result; adding product result and output value to obtain angle of virtual synchronous coordinate system, and based on the angle, obtaining control quantity for generator output voltage phase; based on control quantity, adjusting phase of actual output voltage of GFM DFIG-based WTG by controlling rotor excitation current.

When a control period for executing a process related to sensorless vector control is set as Ts (= 2 * Tc = Th), an estimator applies a high-frequency voltage of a period Th corresponding to a frequency outside an audible domain on a gamma axis of a gamma-delta quasi-synchronous coordinate system in synchronization with Ts and Tc, and detects a stator current including a drive fundamental frequency component and a high-frequency component for each period Tc. At least one of a [gamma]-axis element signal c [gamma] and a [delta]-axis element signal s [delta] is generated by time-differentiating the most recent two stator current detection values for each period Ts in a [gamma] [delta] quasi-synchronous coordinate system, and a [gamma]-axis element signal c [gamma] and / or a [delta]-axis element signal s [delta] is generated using the generated axis element signal. A positive correlation signal pc having a positive correlation with respect to the deviation between the rotor phase and the gamma-axis phase is generated for each cycle Ts, and the positive correlation signal pc is signal-processed so that the positive correlation signal pc becomes zero, thereby generating an estimated value of the rotor phase or speed.