三相四开关整流器因其交流侧某一相直接连接在直流侧两电容中性点之间,存在着电容电压不平衡问题。为了保证电容电压平衡,且进一步提高三相四开关整流器控制系统的稳态性能,提出了一种电容均压的多矢量模型预测控制(multi-vector model ...三相四开关整流器因其交流侧某一相直接连接在直流侧两电容中性点之间,存在着电容电压不平衡问题。为了保证电容电压平衡,且进一步提高三相四开关整流器控制系统的稳态性能,提出了一种电容均压的多矢量模型预测控制(multi-vector model predictive control, MVMPC)策略。针对三相四开关整流器无零矢量问题,建立等效零矢量模型;为保证直流电压的稳定,采用参考功率补偿策略来平衡直流侧电容电压;多矢量模型预测控制方面,每个采样周期选取两个基本电压矢量和一个等效零矢量,这使得等效合成矢量方向幅值均可调,扩大了等效合成矢量的作用范围,提高了系统的控制精度。仿真结果表明,电容均压多矢量模型预测控制策略能使三相四开关整流器可靠稳定地运行,对功率、网侧电流、直流侧电容电压等有着良好的控制效果;与传统的模型预测控制策略(conventional model predictive control, CMPC)相比,所提控制策略具有更小的功率脉动以及更低的电流谐波含量,且开关频率恒定,谐波电流分布规律。展开更多
In this paper, the choice of power quality compensator is a DSTATCOM which constitutes a three phase four leg voltage source converter （VSC） with a DC capacitor. The control strategy proposed for the DSTAT- COM is a...In this paper, the choice of power quality compensator is a DSTATCOM which constitutes a three phase four leg voltage source converter （VSC） with a DC capacitor. The control strategy proposed for the DSTAT- COM is a neural network based one cycle control （OCC）. This control strategy involves neural network block, digital circuits and linear elements, which eliminates the sensors required for sensing the load current and coupling inductor current in addition to the multiplier employed in the conventional method. The calculation of harmonic and reactive currents for the reference current generation is also eliminated, thus minimizing the complexity in the control strategy. The control strategy mitigates harmonic/reactive currents, ensures balanced and sinusoidal source current from the supply mains that are nearly in phase with the supply voltage, compensates neutral current, and maintains voltage across the capacitor under unbalanced source and load conditions. The performance of the DSTATCOM with the proposed artificial neural network （ANN） controllers is validated and investigated through simulations using Matlab software. The simulation results prove the efficacy of the proposed neural network based control strategy under varying source and load conditions.展开更多
文摘三相四开关整流器因其交流侧某一相直接连接在直流侧两电容中性点之间,存在着电容电压不平衡问题。为了保证电容电压平衡,且进一步提高三相四开关整流器控制系统的稳态性能,提出了一种电容均压的多矢量模型预测控制(multi-vector model predictive control, MVMPC)策略。针对三相四开关整流器无零矢量问题,建立等效零矢量模型;为保证直流电压的稳定,采用参考功率补偿策略来平衡直流侧电容电压;多矢量模型预测控制方面,每个采样周期选取两个基本电压矢量和一个等效零矢量,这使得等效合成矢量方向幅值均可调,扩大了等效合成矢量的作用范围,提高了系统的控制精度。仿真结果表明,电容均压多矢量模型预测控制策略能使三相四开关整流器可靠稳定地运行,对功率、网侧电流、直流侧电容电压等有着良好的控制效果;与传统的模型预测控制策略(conventional model predictive control, CMPC)相比,所提控制策略具有更小的功率脉动以及更低的电流谐波含量,且开关频率恒定,谐波电流分布规律。
文摘In this paper, the choice of power quality compensator is a DSTATCOM which constitutes a three phase four leg voltage source converter （VSC） with a DC capacitor. The control strategy proposed for the DSTAT- COM is a neural network based one cycle control （OCC）. This control strategy involves neural network block, digital circuits and linear elements, which eliminates the sensors required for sensing the load current and coupling inductor current in addition to the multiplier employed in the conventional method. The calculation of harmonic and reactive currents for the reference current generation is also eliminated, thus minimizing the complexity in the control strategy. The control strategy mitigates harmonic/reactive currents, ensures balanced and sinusoidal source current from the supply mains that are nearly in phase with the supply voltage, compensates neutral current, and maintains voltage across the capacitor under unbalanced source and load conditions. The performance of the DSTATCOM with the proposed artificial neural network （ANN） controllers is validated and investigated through simulations using Matlab software. The simulation results prove the efficacy of the proposed neural network based control strategy under varying source and load conditions.
