抄録
A single phase transformerless five level cascaded inverter based grid connected photovoltaic system is discussed in this paper. By avoiding the transformer, advantages such as high efficiency and low embodied energy are achieved. The implementation of the cascaded topology allows for reduced AC filter effort, firstly by generating a five level voltage waveform and secondly by achieving minimum switching frequencies by using its switch state redundancies. Control aspects described in this paper are the switching scheme and the grid current control method. A digital implementation and first experimental results of a multi carrier PWM voltage controller showing the effectiveness of the switching scheme are presented.
