| Abstract |
Self-commutated inverters for large photovoltaic power stations have to satisfy two contradictory requirements: high efficiency (i.e. a low switching frequency) and low harmonic distortion of voltage and current in the mains (high switching frequency). The "hybrid-inverter" represents a new concept especially developed for large photovoltaic plants. It produces only low distortions, but has a high efficiency over the whole operation range. It will be realized in "PHALK Mont-Soleil", Europe's largest photovoltaic power plant. The inverter consists of two parallel inverters of different size and switching frequency, i.e. an asymmetrical arrangement which offers new possibilities for operation and optimization. One of the inverters can work as an active filter. This paper presents the design of such an inverter. lts working modes, power ratings and attainable efficiency are explained and discussed. Problems of control and optimized pulse-width-modulation are treated. |
