Quasi-proportional Resonance Research Articles

Linear Active Disturbance Rejection Control of IPMSM Based on Quasi-Proportional Resonance and Disturbance Differential Compensation Linear Extended State Observer

Linear Active Disturbance Rejection Control of IPMSM Based on Quasi-Proportional Resonance and Disturbance Differential Compensation Linear Extended State Observer

Near-zero magnetic field disturbance suppression method based on adaptive filtering and quasi-proportional resonance control

The cardiac magnetic field used for magnetocardiographic (MCG) imaging must be detected in a stable near-zero magnetic field environment. In the hospital environment, there are mainly two kinds of magnetic field disturbances that affect the signal-to-noise ratio of cardiac magnetic field detection. One is the magnetic field disturbance with high power spectral density at a specific frequency, and the other is the random magnetic field disturbance with low frequency. To suppress magnetic field disturbances, this paper proposed a near-zero magnetic field disturbance suppression method that combined a PI controller with adaptive filtering and quasi-proportional resonance control (PI-APF-QPR). The magnetic field disturbance with high amplitude and specific frequency was extracted by the adaptive filter (APF) and suppressed by the quasi-proportional resonance (QPR) controller. Additionally, the low-frequency random disturbance was suppressed by the PI controller. The experimental results showed that compared with the PI controller, the peak-to-peak value of the magnetic field by the PI-APF-QPR controller was reduced by 39.1%, and the suppression ratio of the magnetic field noise by the PI-APF-QPR controller was improved by 29.5%, which verified the effectiveness of the proposed magnetic field disturbance suppression method.

Harmonic Self-Compensation Control for Bidirectional Grid Tied Inverter Based on Crown Porcupine Optimization Algorithm

A self-compensating control strategy for harmonic parameters based on the crown porcupine optimization algorithm is proposed for the single-phase rectifier and two-phase inverter operation mode of the bidirectional converter. In order to improve the response speed of the inverter voltage, the instantaneous expressions of the phase angle coefficient and amplitude coefficient of the dc-side voltage doubling fluctuation are derived, and the third harmonic is calculated based on the crown porcupine optimization algorithm according to the Proportional Integral (PI) + Quasi-Proportional Resonance (QPR) double closed-loop control method and injected into the input voltage of the inverter side to offset the influence of the bus-doubling fluctuation on the output voltage of the two-phase inverters of B and C so that the total harmonic content of the two-phase output voltages of the two-phase inverters of B and C can be reduced. The total harmonic content of the B and C inverter output voltages is reduced. The effective control of the control method for single-phase rectifier two-phase inverter mode is verified through simulation. Finally, the effectiveness of the control strategy is verified by experimenting with a 15 kW LCL-type bi-directional converter prototype.

Research on current harmonic suppression of permanent magnet synchronous motor using smith predictive controller

Abstract Due to the dead time added to the operation of the motor inverter, the generated current harmonics are introduced into the synchronous motor, increasing the harmonic content of the motor. The higher harmonic content is the 5th, 7th, 11th, and 13th current harmonics, which can cause motor torque ripple [1]. To suppress the current harmonics that cause torque ripple, a control method of using a PI controller and a quasi-proportional resonant controller in parallel is considered to suppress current harmonics. However, the introduction of a proportional resonant controller can cause greater overshoots in the current response, and external environmental influences can also generate current disturbances. Therefore, a method based on Smith prediction-PID and quasi-proportional resonance controller cascade control structure is proposed to suppress current harmonics and current overshoot in response to this problem. Finally, the effectiveness of this method was verified through simulation experiments, thereby improving the stability of synchronous motor operation.

Dual-layer loss reduction strategy for virtual distribution transformer integrating energy storage converter

To solve the problem that power quality disturbance aggravates the loss of distribution network in new power systems, this paper proposes a loss reduction strategy for virtual distribution transformer with integrated energy storage converter. Firstly, the concept of the virtual distribution transformer is defined through the analysis of the impact of complex power quality disturbances on distribution network losses. Secondly, a dual-layer control strategy for loss reduction based on the virtual distribution transformer is proposed. In the outer control layer, power quality control considering the load rate of the distribution transformer is achieved by extracting the integrated command signal that incorporates load fluctuations and using the improved quasi-proportional resonance controller. In the inner control layer, a grid-connected power stabilization strategy based on an adaptive double-window moving average filter is proposed, which adjusts the sliding window length in real-time according to the amplitude of fluctuation and state of charge, ensuring power meets the grid-connected standard while improving energy storage charge and discharge margins. Finally, simulation results validate that the proposed strategy enables the rapid realization of functions such as virtual capacity enhancement for distribution transformers, power flow control, and integration of new energy sources within short time scales while effectively reducing operating losses in low-voltage distribution networks.

A Grid-Connected Inverter with Grid-Voltage-Weighted Feedforward Control Based on the Quasi-Proportional Resonance Controller for Suppressing Grid Voltage Disturbances

A grid-connected inverter (GCI) with LCL filters is widely used in photovoltaic grid-connected systems. While introducing active damping methods can improve the quality of grid-connected current (GCC), the influence of grid voltage disturbances can still significantly impact the quality of GCC, leading to stability degradation, especially in weak grid conditions. This paper proposes a grid-voltage-weighted feedforward control scheme based on the quasi-proportional resonance (QPR) controller. This scheme introduces compensatory terms with different proportional coefficients in the voltage feedforward, controlled by the QPR controller. Through a series of analyses, reasonable inverter parameters are first designed. Then, the proposed system model is built in Matlab Simulink. Through simulation experiments and comparisons with various types of operating conditions, the effectiveness of the proposed system scheme is validated. It minimizes the impact of grid voltage disturbances, suppresses the influence of grid harmonics on the control system, improves current quality, and enhances the stability of the GCI system.

Grid-side current harmonic suppression based on Butterworth filter and quasi-proportional resonance controller

Grid-side current harmonic suppression based on Butterworth filter and quasi-proportional resonance controller

Active disturbance rejection speed control of IPMSM based on quasi proportional resonance and feedback differential compensation linear extended state observer

Active disturbance rejection speed control of IPMSM based on quasi proportional resonance and feedback differential compensation linear extended state observer

Adaptive quasi-proportional resonant control with parameter estimation for PMSM sensorless control

Conventional sliding mode control (SMO) utilizes a sign function and a low-pass filter (LPF) to achieve sensorless control of a permanent magnet synchronous motor (PMSM). However, the introduction of the sign function generates a large number of high harmonics, resulting in a significant system output chattering, whereas the addition of the LPF generates control delays and phase shifts. These degrade the PMSM speed and the position estimation accuracy and reduce the system control performance. To improve the performance of the PMSM, adaptive quasi-proportional resonant sensorless control with parameter estimation (AQPR_PE) is proposed. In this control model, an adaptive quasi-proportional resonance controller is used reduce the system output error and to weaken the chattering phenomenon. Meanwhile, the system PMSM parameters are estimated online and fed back to the control model to improve the system parameter robustness and the control accuracy. The Bode diagram, Popov theory, and root trajectory are used to analyze the stability of AQPR, parameter estimation, and AQPR_PE, respectively. Finally, the effectiveness of the proposed method is demonstrated by experimental validation.

An Improved Hydraulic Energy Storage Wave Power-Generation System Based on QPR Control

According to the inherent characteristics of the hydraulic power take-off (PTO) system, the output power of a generator tends to be intermittent when the wave is random. Therefore, this paper aims to improve the effective utilization of wave energy and reduce power intermittency by constructing a topology with two branches to transmit electrical energy. Firstly, the wave-to-wire (W2W) model of the system is constructed. Secondly, the W2W model is simulated by using synovial and quasi-proportional resonance (QPR) control with regular and irregular incident waves, and the results of PI control are compared. Then, the control strategy in simulation is verified by experiments. The simulation and experimental results show that the control strategy has better performance, and the stability of the system output power is greatly improved.

Analysis and Fault-Tolerant Control for Dual-Three-Phase PMSM Based on Virtual Healthy Model

Dual-three-phase permanent magnet synchronous machines (DTP-PMSMs) are famous for their fault-tolerant capability. However, the complex modeling, high copper loss, and torque ripple under postfault operation limit their further application. In this article, a fault-tolerant control (FTC) strategy is developed for DTP-PMSMs under the open-phase fault (OPF) with straightforward modeling and smooth output torque. The virtual healthy DTP-PMSM model, where the coordinate transformation, the modulation strategy, and the controller structure remain unchanged under OPF, is adopted in the proposed FTC scheme. And the current references are derived in sinusoidal waves with minimum copper loss. The inaccurate transmission of control signals under OPF is also focused on. Comprehensive theoretical analysis shows the relationship between the controller output voltage and the actual stator voltage should be considered in the proposed FTC strategy; otherwise, distortion in torque and current will be introduced. The voltage compensation is utilized to compensate for the voltage difference and ensure the smooth torque output. Besides, a quasi proportional resonance controller is designed to further suppress the residual torque ripple. The proposed strategy will not induce complex implementation and heavy computation burden. The simulation and experimental results prove the analysis and the effectiveness of the proposed strategy.

Control Strategy of Photovoltaic Grid Connected System Based on PI and QPR Double Closed Loop Control

The traditional proportional integral (PI) controller in photovoltaic three-phase inverter system has the problems of no static error tracking and poor resonance suppression effect. In order to improve the resonance suppression effect and current control effect of photovoltaic three-phase inverter system, a control strategy of photovoltaic three-phase inverter system based on PI and quasi proportional resonance (QPR) double closed-loop control is proposed. The control strategy and control block diagram based on PI and QPR double closed-loop control are designed to realize no static error tracking of incoming current, which has better waveform of incoming current and resonance suppression effect, and improves system stability. Finally, the effectiveness of the control strategy are verified by simulation.

Coordinated control scheme of a hybrid renewable power system based on hydrogen energy storage

An all-weather energy management scheme for island DC microgrid based on hydrogen energy storage is proposed. A dynamic model of a large-scale wind–solar hybrid hydrogen-generation power generation system was established, using a quasi-proportional resonance (QPR). We used the distributed Nautilus vertical axis wind power generation system as the main output of the system, and it used the photovoltaic and hydrogen energy storage systems as alternative energy sources. Based on meeting the load power requirements and controlling the bus voltage stability, we can convert the excess energy of the microgrid to hydrogen energy. With a shortage of load power, we can convert the stored hydrogen into electrical energy for the load. Based on the ANSYS FLUENT software platform, the feasibility and superiority over large-scale distributed Nautilus vertical axis wind power generation systems are verified. Through the MATLAB/Simulink software platform, the effectiveness of the energy management method is verified. The results show that the large-scale distributed Nautilus vertical axis wind power generation system runs well in the energy system, produces stable torque, produces energy better than other types of wind turbines, and has less impact on the power grid. The energy management method can ensure the normal operation of the system 24 h a day under the premise of maintaining the stable operation of the electric hydrogen system without providing external energy.

Frequency Coupling Admittance Modeling of Quasi-PR Controlled Inverter and Its Stability Comparative Analysis Under the Weak Grid

This paper intends to comparatively study the stabilities of grid-connected inverters with three closely related controllers: quasi-proportional resonance (quasi-PR), proportional integral (PI), and proportional resonance (PR) under the weak grid. Firstly, considering the influence of frequency coupling characteristic, a frequency coupling admittance model of quasi-PR controlled inverter is established. Then, the admittance characteristics of the quasi-PR, PI and PR controlled inverters are compared. Admittance characteristics of the PI and PR controlled inverters are similar while the quasi-PR controlled inverter is quite different: the amplitude of the quasi-PR controlled inverter is larger than that of the PI controlled inverter and the phase difference between the two inverters is obvious in the mid-high frequency areas, which are mainly caused by the resonance bandwidth of the quasi-PR controller. Furthermore, the stabilities of the quasi-PR, PI and PR controlled inverters are analyzed. The stabilities of the PI and PR controlled inverters are similar but the quasi-PR controlled inverter is more sensitive to weak grid and high inverter output power. To achieve the same system stability, the voltage outer-loop bandwidth of the quasi-PR controlled inverter should be designed narrower than that of the PI and PR controlled inverters. Finally, experiments verify the correctness of the analyses.

Design of Inverter Side of Modular Grid Simulator Based on Proportional integral-Quasi-proportional resonance Control

The tracking of a given voltage in the traditional double closed-loop proportional integral control in the current power grid simulator has problems such as static difference, delay and oscillation. It is proposed that the voltage outer loop and current inner loop of the inverter side of the power grid simulator adopt proportional integral and quasi-proportional resonance control respectively, and the topology of the inverter adopts a cascaded modular design to establish a single-phase inverter model. Compared with the traditional double closed-loop proportional-integral control, it is verified that the proportional-integral-quasi-proportional resonant controller can effectively improve the system’s ability to track the command voltage and the stability of the output voltage.

Analysis on Circulating Current and Split Capacitor Voltage Balance for Modular Multilevel Converter Based Three-phase Four-wire Split Capacitor DSTATCOM

We propose a modular multilevel converter (MMC) based three-phase four-wire (3P4W) split capacitor distribution static synchronous compensator (DSTATCOM), aiming at compensating unbalanced and reactive load currents. Due to the zero-sequence current compensation, the circulating current characteristics of 3P4W MMC-DSTATCOM are different from conventional MMCs. Moreover, the distinct working principle of MMC would affect the features of split capacitor voltage. The decoupled positive-, negative- and zero-sequence second-order and DC components of the circulating current are deduced explicitly. Two proportional-integral controllers with dual dq transformation are employed to suppress the positive- and negative-sequence components of second-order circulating current, while quasi proportional-resonance controller is designed to eliminate the zero-sequence component. Besides, the phenomenon of the unbalanced split capacitor voltages is revealed, and fast-tracking balancing method by controlling zero-sequence current flowing through the split capacitors is provided. Digital simulation results verify the accuracy of the analysis and the feasibility of the suppression methods.

Rotation‐frequency oscillations suppression strategy for AC drive system with large inertia rotating load

Mechanical faults in AC drive systems lead generally to periodic load torque ripple which reflects as speed vibration and leads to harmonic components in motor stator current. The deterioration of speed and stator current, called rotation-frequency oscillations in this study, may degrade motor control accuracy and even cause for instability. In this study, a strategy using active control of stator current is proposed to suppress the rotation-frequency oscillations in AC drive systems. First, the magnetomotive force and permeance approach is used to study the influence of the mechanical faults on the stator current of permanent magnet synchronous motor (PMSM). Second, in the proposed strategy, an improved current regulator cascading a proportional–integral regulator with a quasi-proportional resonance (QPR) regulator is designed, and the mechanism of rotation-frequency oscillations suppression strategy is analysed. In addition, digital realisation method and parameters design process for QPR regulator are introduced. Experimental evaluation of the proposed strategy is implemented on a PMSM traction system under mechanical faults, load disturbance and so on. Test results show that with the proposed strategy, speed vibration and current harmonic components caused by mechanical faults are suppressed significantly.

A Novel Grid-Connected Current Control Method Based on Frequency Adaptive Proportional Resonance

In this paper, a novel quasi-proportional resonance (quasi-PR) controller for grid-connected current control is proposed. For the traditional quasi-PR controller, the performance decreases in cases when a large gird frequency deviation is going through. To solve the problem, a frequency adaptive structure is applied in the current control method to achieve online correction on the resonance frequency, so that a high control accuracy is maintained and the robustness of the control system is enhanced. The feasibility of the proposed method has been verified by experimental results.

Research On VSG Comprehensive Control Strategy For Power Grid Voltage Sag

Virtual Synchronous Generator (VSG) photovoltaic inverter still has the problems of surge current and voltage overcharge when the grid voltage drops. Aiming at the problems mentioned above, the comprehensive control strategy for AC/DC is proposed. The direct current (DC) side adopts the strategy of super-capacitor energy storing and switching Maximum Power Point Tracking (MPPT) derating, the alternating current (AC) side adopts the control strategy of virtual impedance and the vector difference of limited voltage, which are based on the quasi-proportional resonance. Particle swarm optimization (PSO) is used to optimize its parameters because of the difficulties in adjusting parameters of quasi-proportional resonance control by experience. This strategy can track on the voltage with no difference when the voltage is normal, it can also limit the overcharging voltage and the surge current into the demanded range when the voltage drops. Finally, the effectiveness of the strategy proposed in the paper is verified by simulation.

Application of Repetitive Control in Electric Spring

With the increasing of the grid-connected capacity of renewable energy such as wind energy and solar energy, its instability, intermittence and uncontrollability have a serious impact on the stable operation of power system, such as voltage fluctuation, frequency flicker, etc. Therefore, Electric Spring (ES) system has become a current research hotspot. Aiming at the deficiencies of the resonance control strategy, a control method that combines quasi-proportional resonance (QPR) control and repetitive control is proposed. The quasi proportional resonance control is used to realize the tracking without static error, and the internal model principle of repetitive control is used to suppress the periodic disturbance of the grid voltage, so as to improve the power quality of the grid. Compared with the traditional quasi proportional resonant control, the introduction of repetitive control can effectively improve the steady-state accuracy, reduce the system harmonic and enhance the ability of anti-harmonic interference. The modeling of ES and the design method of repetitive controller parameters are discussed in detail. The simulation model is built using MATLAB / Simulink, and the ES experimental platform is built with dSPACE as the control core, the results verify the feasibility and effectiveness of the proposed control strategy.