Abstract——The distributed power generation systems based on the renewable energy sources, such as solar photovoltaic, wind power, geothermal power, have been the focus of the world in the latest years. The grid-connected inverter is important power electronic implements, used to transfer the power from the DPGS to the public grid, and the quality of its output power has been studied a lot. The repetitive control technique based on the internal model principle, can achieve low steady-state tracking error and total harmonic distortion (THD) in AC systems, so it is widely adopted in the inverter systems. However
in the practical applications, there are still some issues needs solving when using the repetitive control technique. To suppress the current distortion, a control strategy of fundamental current and harmonics controlled separately is adopted. On the synchronous rotating coordinate, the fundamental component is direct value and the harmonic component is alternating value. Proportion-integral (PI) values above which can achieved output controlJer and proportion resonant (PR) controller are adopted to control the power adjustment and zero error control of harmonic restrain.
2021-08-26 14:08:29
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ABSTRACT
Due to the power-grid low-order harmonic voltage and the nonlinearity of power electronic devices, the grid-connected converter of wind power generation system produces grid-connected harmonic current. In order to improve the output power quality of full-power grid-connected converter of wind power generation system, based on the detailed analysis of the harmonic mathematical model of grid-side converter, a cross-coupling control strategy for suppressing the low-order harmonic current components is proposed in this paper. In this control strategy, the DC component of each grid-connected harmonic current is detected in the multi-synchronous rotating coordinate system, and the current cross-coupling control method is adopted to realize the accurate control of each harmonic current. The harmonic current cross-coupling controller is analyzed and designed in detail. The proposed control strategy takes into account the cross-coupling effect of each harmonic current, which can effectively reduce the interaction between each harmonic current and the fundamental current, and improve the stability of the system. Simulation and experimental test verify the correctness and feasibility of the proposed control strategy.
2021-08-25 17:05:36
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一种基于自适应神经网络的谐波电流检测方法的仿真，张国荣，王英，有源电力滤波器（APF）的性能很大程度上取决于其采用的谐波电流检测方法。本文介绍一种基于自适应神经网络的谐波电流检测方法，这
2021-05-08 20:38:54
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文中的模型，本人空间中都上传了，可以自行下载。
这是其摘要
随着电力电子器件和各种非线性设备的使用，以及用户对电能质量要求的不断提高，电能质量中的无功补偿问题显得越来越重要。静止同步补偿器（STATCOM-Static Synchronous Compensatory）以其对系统无功功率补偿的优越性能，成为目前电力系统中最具代表性的无功补偿装置之一，是近年来电力电子与控制领域研究的热点。
首先，本文针对STATCOM系统设计中的关键问题之一，即无功电流的实时检测，介绍了基于p、q运算方式的无功电流检测方法、基于ip、iq运算方式的无功电流检测方法和无锁相环的三相电网无功电流检测法这三种无功电流检测方法的原理，并在MATLAB/simulink中进行了仿真验证，然后对比分析了它们在三相四线制电网负载不平衡和三相电压有频率偏移和畸变的情况下，实时检测无功分量的能力。
然后选定系统容量为10Kvar，电压级别为380V，statcom模块选择三单相桥式主电路拓扑，对逆变电路、整流电路、直流侧电容，交流侧连接电感等参数进行了理论设计。
然后，介绍了电流间接控制和电流直接控制中的几种控制方法的原理，并在MATLAB/simulink中进行了仿真验证。
最后，在MATLAB/simulink仿真环境下，在三相四线制电网负载不平衡的情况下，对三种不同检测方式和控制方式的组合控制的系统进行了实时无功补偿的仿真研究，对其中的参数进行调节，从三组仿真模型的a相电压电流补偿前后的波形图和反馈跟踪情况的波形图进行了比较分析，分析了各检测方法和控制方法的优劣。结果证明了静止同步补偿器实现抑制三相不平衡，实时补偿无功分量的可行性。
2021-04-14 20:21:40
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针对谐波抑制中谐波电流检测不够准确的问题,提出基于标准正弦波的ip-iq谐波电流检测方法.该方法以瞬时功率理论为基础,在传统ip-iq谐波电流检测法中引入标准正弦波直接构成单位C矩阵,标准正弦波以电网电压基波正序分量的频率f和初相位θ为参数生成.因为标准正弦波的频率非常稳定,所以基波和谐波检测较为准确,同时避免出现间谐波.建立了模型,并利用Simulink仿真对比分析,结果表明,此方法提高了基波电流和谐波电流检测精度.
2021-04-13 16:03:58
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