三相光伏并网逆变器及其控制

三相光伏并网逆变器研发与智造

专业：控制理论与控制工程

在职研究生：张秀云（上海红申电气有限公司工程师）

指导教师：刘一鸣（教授级高工）

摘要

光伏并网发电过程是将直流电变为交流电并将能量输送给电网，逆变器是太阳能电池和大电网连接的核心设备，它的稳定性和可靠性决定了输送电能的质量，为了提高发电质量，需要对系统的硬件和软件做深入的分析。本文对这两个方面都做出了比较详细的数学推导，并进行了理论仿真，然后在此基础上搭建了硬件平台，对这些算法进行了初步的验证，给出了相应的实验结果。

首先，本文对光伏阵列的结构进行了分析，并搭建了阵列的仿真模型，从仿真模型的P—U曲线可以看出阵列存在最大输出功率，并在此基础之上就最大功率跟踪问题做出了深入思考，在传统的算法基础之上提出了一种算法，仿真表明该算法比传统算法具有更好地跟踪效果。

接着，本文对逆变器的拓扑结构做出了说明，并选择了单级式的拓扑结构作为本文研究对象。对于L型和LCL型的滤波器结构而言，其数学模型是不同的，并网电流的控制算法也要做相应的改变。对于电压型逆变器，本文采用直接电流控制，分别对滞环控制和三角波比较控制做出了分析。特别地，对于LCL型滤波器在同步坐标系下因其复杂的解耦，本文引入了PR控制，搭建了matlab仿真对上述算法进行了仿真和对比分析。

最后，本文就L，LCL滤波器还有采样电路进行了理论计算，搭建了实验平台，用TMS320F2812做核心控制器对理论算法进行了初步的验证，给出了实验波形。

关键词：光伏并网发电最大功率点跟踪直接电流控制PR控制红申电气

Three-phased Photovoltaic Grid-connected Inverter And Control

Speciality: Control Theory and Control Engineering

Name: Zhang Xiu yun

Supervisor: Professor Wang Xiaolei

Abstract

The photovoltaic power generation process is making the direct current to the alternating current and transmissing to the grid, the inverter is the core equipment of the connection between solar cells and grid, its stability and reliability determine the quality of the electrical energy transmission.In order to improve the quality of power generation, a in-depth analysis on hardware and software of the system have done. This paper have made a more detailed mathematical derivation and theoretical simulation on these two aspects, have also made a preliminary validation of these algorithms and given the corresponding experimental results on a hardware platform.

First, this paper analyzes the structure of the photovoltaic array, then builds a simulation model of the PV array. The exist of maximum output power of the P-U curve can be seen from the simulation model, a deep thinking of the maximum power point tracking also have done on this basis, and proposes a new algorithm simulation shows that has a better tracking results compared with the traditional algorithm.

Then, this paper describes the topology of the inverter, and selects single-stage topology as a research object. For L-and LCL-filter structure, the mathematical model is different, and the net current control algorithms also need to do the appropriate change. In this paper,direct current control is used on voltage source inverter, and respectively analysises hysteresis control and the triangle wave comparing control. In particular, because decoupling of the LCL type filter in the synchronous coordinate system is complicated, this paper introduces PR control, sets up a matlab simulation to simulate and give comparative analysis of the above algorithm.

Finally, this paper gives theoretical calculations of the L-and LCL-filter and sampling circuit, builds an experimental platform using TMS320F2812 as core controller to do a preliminary validation of the theoretical algorithm, and gives the experimental