Function multiplexing type energy storage converter off-grid control system and method

The invention provides an off-grid control system and method for a function multiplexing type energy storage converter. The off-grid control system comprises a voltage acquisition module, a current acquisition module, a double-loop control module, a positive and negative sequence separation module, an unbalance compensation calculation module, a harmonic compensation calculation module and a switching pulse generation module. According to the control system and method provided by the invention, multi-objective optimization of the output voltage of the function multiplexing type energy storage converter can be realized; a negative sequence voltage modulation signal is obtained based on the unbalanced component of the voltage introduced by the unbalanced compensation calculation module, so that the energy storage converter has the capacity of negative sequence compensation, and the unbalance degree of the output voltage is reduced; the harmonic voltage modulation signal obtained by introducing the voltage harmo