A method for large-scale WEC connecting to island isolated microgrid based on multiple small power HPGSs

As isolated microgrids with diesel generators have difficulties meeting the power fluctuations caused by intermittent renewable energy sources (RES), a combination method, which splits a high power hydraulic power generation system (HPGS) in wave energy converter (WEC) into multiple low power HPGSs, was implemented in order to reduce the magnitude of fluctuations in grid connections. A reliable grid connection based on a DC voltage source mode inverter was proposed for multiple HPGSs. A simulation model for an isolated microgrid was developed, which included WEC, HPGS, power electronic conversion system (PECS), and diesel generator. Comparative tests were carried out between multiple HPGSs and single HPGS and feasibility of connecting a large-scale WEC to isolated island microgrid was verified. Multiple HPGSs have been shown to have a lower impact on the grid when operating at the same total rated power of the generator. The research results have been applied to large-scale WECs such as the Zhou Shan Hao, which has a total power of 500 kW, establishing the groundwork for connecting large-scale WECs to isolated microgrid on islands powered by diesel generators.

Automated summary

In this study, a combination method was implemented to split a high power hydraulic power generation system (HPGS) in a wave energy converter (WEC) into multiple low power HPGSs, aiming to reduce power fluctuations in isolated microgrids. The research results showed that multiple HPGSs have a lower impact on the grid when operating at the same total rated power of the generator. This method has been successfully applied to connect large-scale wave energy converters to isolated microgrids powered by diesel generators.