Along with the worldwide more attention to environment and rapid development of photovoltaic industry, the PV water pumping system has rapidly developed, the economic advantage of which brings it into prominence. It was estimated, up to now the operating PV water pumping systems in the world may exceed hundreds thousand sets and with a driving increasing tendency. In many cases the distributed stations gain the advantages over PV feed-in grid-connected pump. The majority of the PV pumping systems are driven by an ac asynchronous motor, which are generally of lower efficiency, especially for small-scale systems. A dc permanent magnetic, brushless, sensorless and casting resin motor are developed and used in PV water pumping systems, the experiments and operations of 19 demonstrative stations in Guangdong show that the results on economics and reliability are excited. It can save even 15% ~ 20% PV modules in comparison with an asynchronous motor driven under same sunshine, water head and flow. An example of comparison between systems with batteries and without batteries is also given in this paper. Finally the commercialization, marketing and subsidy policies of PV water pumping system in China are discussed.
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