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提出一种模块化逆变器组成的光伏并网系统欧洲效率优化控制方法,各并网逆变模块共直流交流母线并联运行。分析直流母线电压变化趋势与发电功率的内在关系,在逆变模块中采用两个不同限幅值的直流母线电压调节器,根据系统发电功率的变化,自然启用相应的电压调节器,确保各逆变模块优先运行在设定的最高效率点,而当系统发电功率较大时逆变模块再转向满载运行,从而优化系统欧洲效率,且无需增加硬件成本。详细分析系统的工作原理,给出控制方法的实现方式和关键参数的设计准则。搭建实验原理样机,进行动稳态实验和效率测试。实验结果表明,系统欧洲效率提高了0.43%,验证了控制方法的有效性。“,”A novel control method to improve the European efficiency for modular grid-connected PV generation systems was proposed. The modular inverters in parallel operation share both the DC and AC bus. Two DC bus voltage regulators with different output limits were employed in each inverter module, based on the inherent relationship of DC bus voltage and generation power. And the suitable one of the regulators was enabled naturally by the PV power to run the inverter at the highest efficiency point as the first choice, and at the full load point only if the PV power is high enough. As a result, the European efficiency of the system was optimized at no additional hardware cost. The operational principle of the system was analyzed in detailed with the implementation for the control and design guideline for key parameters given. The analysis is verified with both the state-steady and dynamic experimental results. And the tested European efficiency of the system is improved by 0.43%