The invention relates to a control method for a micro-grid
hybrid energy storage system. The control method comprises the following steps: selecting inductive current i L (lower coordinate) and
capacitor voltage u c (lower coordinate) as state variables, and
energy storage unit
voltage u i (lower coordinate) and load current i Load (lower coordinate) as input variables for a buck /
boost power converter in the micro-grid
hybrid energy storage system; building a
small signal model of buck /
boost power converter based on PWM (Pulse-Width Modulation) complementary control; respectively designing control circuits for a storage battery and a super
capacitor; controlling the charging and discharging of the storage battery and stabilize low-frequency component of synthetic load through a single
current loop; stabilizing the difference between the synthetic load power and storage battery power through the upper
capacitor; adding power feed-forward to the
voltage-current double closed-
loop control so as to inhibit the fluctuation of the voltage of a
DC bus. According to the control method for the micro-grid
hybrid energy storage
system, each load power in a micro-grid is taken into full account, a plurality of control methods are carried out to stabilize the high-frequency fluctuation of power, thus the fluctuation of the voltage of the
DC voltage is inhibited, and the stability of the voltage of the
DC bus in working is maintained.