The hydraulic energy storage wave energy converter is unable to achieve maximum power point tracking due to the decoupling effect of accumulators. In addition
the hydraulic generator sets with uncontrollable rectification mode result in the frequent starts and stops
uncontrollable power output
and failure to adaptively track the incoming wave power. Therefore
a power tracking control method based on high-frequency rectification is proposed. The mathematical models of the hydraulic energy storage power generation system and pressure load are established. On this basis
the generator speed is controlled by a high-frequency rectifier
thereby improving the output characteristics of the hydraulic power generation system. It achieves automatic tracking of the incoming wave power by the hydraulic generator set within the power variation range. The simulation test results indicate that the input flow of the hydraulic motor rate can automatically track the output flow rate of the hydraulic cylinders
and the system pressure can automatically match the incoming wave power. Therefore
the power tracking control method enhances the characteristics of the hydraulic generator set of the wave energy converter and reduces the starts and stops
thereby achieving both wave power tracking and adaptive load regulation. It is beneficial in promoting the further research on the hydraulic energy storage wave energy converter.
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