三相电压型光伏并网装置控制策略的研究

Study on Control Strategy of Three Phase Voltage-type Photovoltaic Grid-connected System

随着传统能源的日益枯竭,太阳能无疑是极具发展潜力的新能源。光伏发电(太阳能)可分为独立供电和并网发电两种;重点研究三相光伏并网系统的控制策略,阐述了利用电网电压前馈补偿以及电流跟踪技术并网的原理,针对单级式光伏并网发电(此结构的特点就是效率高,但必须在一个功率变换环节实现升压、最大功率跟踪、DC/AC逆变,控制相对复杂),利用d-q变换,得到了一种有功功率和无功功率分别独立进行控制的方法;最后通过建立相关的MATLAB控制模型进行仿真,实现了网侧电流的正弦化及单位功率因数,验证了设计的正确性。

With the increasing depletion of conventional energy,solar energy is undoubtedly the most potential for development of new energy sources.Photovoltaic power can be divided into an independent power supply and grid-connected systems.In this paper,discussed 3-phase grid-connected photovoltaic system control strategy,described the use of voltage feed-forward compensation and the principle of current tracking technology,to discuss a single-stage photovoltaic grid-connected,the biggest feature of this model is efficient,there is only one aspect of energy conversion,a simple topology,but the relative complexity of control,achieve maximum power tracking and sine wave grid connected current at the same time.Proposed a way that active power and reactive power are controlled separately.Finally,through the MATLAB simulation,establishment the control model,realized the sine wave grid connected current and unity power factor.The correctness and availability of such theory are proved by the simulation and experiments.