An active control scheme for MMC based energy storage device

Abstract

The MMC based energy storage device is a type of bi-directional power device. Both the MMC and the energy storage device are key infrastructures in the future medium and high voltage networks. The MMC converter enables the capability of embedding the battery into the sub-module of the MMC distributively. The MMC based energy storage device employs the MMC converter as the power exchange interface and the battery as energy storage device. An active control scheme for the MMC based energy storage device consists of the bi-directional power interface topology and the active control strategy. The bi-directional power interface in the device is established based on the MMC sub-module and the buck-boost circuit. The active control strategy consists of the MMC grid-connection control method and the energy storage control method. The MMC based energy storage device can buffer the power fluctuation in the applications of renewable energy grid-connection or power transmission between the AC grid and the DC grid.