13results about How to "Improve steady state performance" patented technology

The application discloses a data-driven optimal control method for a grid-connected inverter. The method comprises the following steps: constructing a DeePC optimization controller of the grid-connected inverter on the grid side; acquiring a data matrix of the grid-connected inverter in a preset historical period and an initial trajectory after a preset adjacent period, inputting the controller, setting parameters for different control targets and types of the grid-connected inverter, outputting an optimal input data sequence after processing, generating a sinusoidal pulse width modulation wave signal and acting on the grid-connected inverter, and realizing data-driven optimal control. The method can automatically perceive and adapt to the dynamic characteristics of the actual power grid through real-time data-driven predictive control, can present or enhance the control behavior of the grid-constructing or grid-following inverter by modifying the cost parameters, can realize multi-mode flexible, optimal and coordinated control, has excellent dynamic response and steady-state performance, is beneficial to safe and stable operation, and improves the ability to adapt to complex and variable operating conditions and power grid strength.

This invention discloses a predictive current control method and system for a GaN-based permanent magnet synchronous motor. The method includes: predicting the current of each voltage vector among multiple voltage vectors of the inverter based on a predictive current model to obtain multiple predicted currents; filtering the multiple voltage vectors according to the multiple predicted currents and a first cost function to obtain candidate voltage vectors; determining the duration of action of the candidate voltage vectors; if there are multiple candidate voltage vectors, filtering them according to the duration of action of the multiple candidate voltage vectors and a second cost function to obtain the optimal voltage vector; and controlling the inverter according to the optimal voltage vector and its duration to control the operation of the permanent magnet synchronous motor. This improves the overall steady-state performance of the motor while reducing the computational load, thus lowering the complexity of the control method.

This invention provides a model predictive control method for a six-phase electric drive reconfigurable on-board charging system, belonging to the field of power electronics and electric drive technology. It solves the problems of high current ripple and heavy computational burden on the system. The technical solution includes the following steps: S1: Obtaining the q-axis current setpoint; S2: Obtaining the real-time 0 / 1 axis current setpoint; S3: Acquiring the six-phase current of the six-phase symmetrical permanent magnet synchronous motor; S4: Calculating the predicted current for the next cycle; S5: Selecting the voltage vector for the next cycle; S6: Obtaining the on / off state of the switching transistors in the next cycle; S7: Realizing the operation mode of the six-phase electric drive reconfigurable on-board charging system based on the drive signal of the six-phase inverter. The beneficial effects of this invention are: it can improve the dynamic and steady-state performance of the system while reducing the computational burden and lowering zero-sequence current ripple, and has broad application prospects.

The application discloses a non-singular fast terminal sliding mode vibration active control method based on a compensation function observer, 1) according to elastic dynamics, a fourth-order modal equation of a four-side fixed support plate structure driven by an electromagnetic inertial actuator is established; 2) in view of external unknown interference and modeling uncertainty existing in the system, a compensation function observer is designed to realize real-time estimation and compensation; 3) a non-singular fast terminal sliding mode surface is constructed, and a sliding mode control law is designed in combination with the observer output, so that the singularity problem of a traditional terminal sliding mode is solved, and the time for system state to reach a balance point is shortened through a fast convergence term; 4) a comparison experiment is designed, and the composite control method designed in the application can significantly reduce the vibration amplitude of the four-side fixed support plate while guaranteeing the finite time stability of the system, and has stronger anti-interference ability and higher vibration suppression precision compared with the traditional sliding mode control.

This invention relates to a sensorless control method for permanent magnet synchronous motors (PMSMs) with low observation error under multiple operating conditions, belonging to the field of motor control technology. The invention establishes a mathematical model of the PMSM in a stationary coordinate system and a classical back-EMF observer; based on the observed back-EMF values ​​after coordinate transformation, an adaptive gain characterizing the rotor motion direction is designed; a cosine value of the rotor position estimation error is constructed, and an adaptive gain feedforward orthogonal high-order phase-locked loop (PLL) is used, along with an ideal low-pass filter, to obtain estimates of the rotor speed and position. This invention can more effectively reduce the influence of complex operating conditions on the motor position estimation error, providing more reliable speed estimation and rotor position signals for the field-oriented control of the motor. The sensorless control strategy for PMSMs with low observation error under multiple operating conditions proposed in this invention can achieve speed control when the motor is in reverse, exhibiting good dynamic and steady-state performance.

This invention provides a circuit topology and control method for high-power power conversion devices. This circuit topology exhibits low switching losses and high conversion efficiency in applications requiring high-frequency power switching. The invention also provides a power conversion device utilizing this circuit topology, outlining the device layout and transformer winding method. While meeting the requirements for high-power output, this further reduces the size and losses of the power conversion device, improving its steady-state and dynamic performance. Furthermore, this invention provides a voltage equalization control scheme to achieve voltage balancing between two high-voltage sub-circuits.

The invention provides a permanent magnet synchronous motor current controller design method, a current controller and a permanent magnet synchronous motor. The permanent magnet synchronous motor current controller design method comprises the steps of 1, designing a model-free nonsingular terminal sliding mode current controller; 2, designing a quasi-resonance regulator; and step 3, a quasi-resonance compensation step: respectively connecting two ends of the d-axis model-free nonsingular terminal sliding mode current controller and the q-axis model-free nonsingular terminal sliding mode current controller in parallel with a quasi-resonance regulator. According to the current controller design method, a current tracking controller of a permanent magnet synchronous motor with a current tracking function is designed, and the two ends of a d-axis model-free nonsingular terminal sliding mode current controller and the two ends of a q-axis model-free nonsingular terminal sliding mode current controller are respectively connected with a quasi-resonance regulator in parallel. Therefore, the motor not only has good dynamic performance, but also can effectively reduce the current fluctuation, suppress the torque ripple and improve the steady-state performance.

The invention discloses an intelligent optimal control method for a networked system, and the method comprises the steps: S1, building a dynamic model of an uncertain strict feedback nonlinear system, and defining an event triggering mechanism based on a relative threshold value; s2, performing online approximation on an unknown nonlinear function in the system by adopting a radial basis function neural network; s3, based on a backstepping method, defining a coordinate transformation error variable, and designing a virtual control law and a parameter adaptive law for the intermediate subsystem; s4, based on the event triggering mechanism and the Lyapunov stability theory, an actual control law and an inverse optimal control law are designed, and a relation exists between the inverse optimal control law and the actual control law; and S5, executing event trigger control according to the actual control law and the event trigger mechanism, and applying the control signal meeting the inverse optimality to the controlled object to realize closed-loop stable control. According to the invention, the problems of signal discontinuity, system uncertainty and network resource limitation can be solved.

The application discloses a kind of centrifugal pump dynamic performance optimization method under given flow mutation, first deduce the maximum slope when motor torque rises and falls;Second, the turning point of torque instruction mutation is deduced;Finally, the corresponding torque instruction is sent out: when flow mutation time to turning point, this section of time gives forward vector, so that torque rises according to maximum slope, after reaching turning point, give retreat vector, so that torque falls at maximum slope, until torque returns to initial value, speed tracks on mutation after given speed, flow reaches given flow, system reaches stable state.The application controls torque linearly in dynamic time, and the control rate is the hardware limit value.A linear differential equation is constructed with the torque integral of dynamic imbalance and the given speed increment being equal as a constraint to solve the torque turning point, which makes up for the speed overshoot of traditional speed PI loop, and realizes the optimal torque control curve and optimal flow response curve under dynamic linear control.

This invention relates to a speed control method and electronic device for permanent magnet synchronous motors (PMSMs) based on singular perturbation theory. The method includes: establishing a singular perturbation model of the PMSM and decoupling it into a fast-changing subsystem and a slow-changing subsystem; constructing an amplitude control set model predictive controller to obtain a voltage amplitude candidate set and establishing a current prediction model; calculating a q-axis current reference value based on a deadbeat controller; constructing a cost function based on the q-axis current reference value; using the cost function and the current prediction model to traverse the voltage amplitude candidate set; selecting the voltage combination with the minimum cost function as the optimal voltage control signal; and driving the PMSM based on the optimal voltage control signal. Compared with existing technologies, this invention has advantages such as improved current tracking accuracy, suppression of harmonics and torque ripple, ensuring rapid tracking of speed commands, and simultaneously meeting the requirements of high dynamics, high precision, and robust control of motor speed.

The application belongs to the technical field of organic semiconductor material processing, and particularly relates to a solvent for dissolving an organic semiconductor material and application thereof in preparing an organic optoelectronic device. The application discloses a solvent for dissolving an organic semiconductor material, wherein the solvent is a fluorine alcohol reagent. The fluorine alcohol solvent of the application is a strong hydrogen bond donor, and has good solubility for most organic polymer and small molecule materials of a pi conjugated system, and the solubility is better than that of chloroform, chlorobenzene and other solvents. Organic semiconductor material dissolved by the fluorine alcohol solvent or a composition thereof of the application is spin-coated on a substrate to prepare an organic electrochemical transistor device. Compared with a chloroform solvent, the steady-state performance and stability of the device are significantly improved. In addition, compared with aromatic and chlorinated solvents commonly used in organic electrochemical transistors, the fluorine alcohol solvent is an environmentally friendly solvent, is more environmentally friendly, has lower toxicity, and is an ideal solvent for dissolving an organic semiconductor material.

This invention discloses a distributed satellite attitude cooperative anti-saturation control method at a predetermined time. First, a SAR satellite formation model considering saturation constraints is established. Then, a preset performance boundary function that converges within a specified time is designed. Next, problems such as external interference and actuator saturation constraints in the satellite formation flight system are addressed. Finally, a SAR satellite attitude cooperative control law at a predetermined time is designed based on an anti-saturation compensator, an interference observer, and sliding mode control. This invention enables the formation satellites to achieve convergence of attitude cooperative errors within a specified time under actuator saturation constraints, while remaining within the preset performance boundary. It also features high control accuracy, good control performance, and fast convergence speed.

The application relates to the technical field of robot control, in particular to a robot low-communication load fault-tolerant control method for complex working conditions, which comprises the following steps: constructing a robot system dynamics model containing unknown dynamics of a system, external disturbance and multiplicative and additive faults of actuators; combining actual positions and expected positions of joints in the robot system, defining a constrained joint position tracking error according to a preset performance function, and then converting the constrained error variable into an unconstrained error variable through a bijective error transformation; constructing a virtual control law, and designing a speed tracking error and an error compensation signal through a finite time command filter; introducing a fuzzy logic system to approximate the unknown dynamics of the system; designing a fixed-time disturbance observer for estimating a composite disturbance; combining a relative threshold event trigger mechanism to construct a final fault-tolerant control law; and the application can ensure the robot trajectory tracking precision and the global consistent boundedness of closed-loop system signals under the conditions of unknown model, actuator fault and external disturbance.