微型光伏分布式发电系统能量优化控制研究

POWER OPTIMAL CONTROL FOR MICRO PHOTOVOLTAIC DISTRIBUTION GENERATION SYSTEM

以一个由光伏电池、蓄电池和燃料电池组成的微型直流分布式发电系统为对象,采用无通信方式实现系统能量优化控制。通过使用母线电压信号来实现电源间能量的最优化分配,对光伏电池进行MPPT和母线电压调节相结合的控制,实现可再生能源的充分利用及轻载时的可靠运行。对蓄电池和燃料电池接口变换器进行有效控制,使其能在光伏电池发电量及负载波动时,适时充电或放电,从而保证母线电压的稳定,实现系统能量的均衡控制。同时考虑了系统带有冲击负载运行的情况,并且采取有效的控制措施对冲击负载的影响进行限制。修正的上扬特性控制减小了线路阻抗对母线电压的影响。给出了接口变换器的控制及系统能量优化控制的实现规则,并通过仿真试验验证了该控制方法的正确性。

The DC distributed power generation system is composed of PV module, battery and fuel cell. Voltage level signal and the bus voltage rising adjustment is combined to control the system. Then its control principles and specific control methods were explained. This method can achieve the optimal assign of energy among the distribu- tion generators by using the signal of bus voltage. The PV modules can make full use of renewable energy and work stably in light loads by combining MPPT and the bus voltage regulatory control. Effective control methods were a- dopted for the interface converters of the battery and the fuel cell, through which the battery and the fuel cell could be charge or discharge timely in the presence of fluctuating output power of the PV array or loads. It ensured the stability of the bus voltage and achieved the balance of the system＇ s energy. At the same time the affect of the im- pact load was taken into account. The rising control would decrease the impact of the line impedance on the bus voltage. This control method has the advantages of high reliability, simple control structure and high bus voltage. The control interface structure of the power converter and optimal energy control of the system was presented. A simulation results verify that the control method is right.