Abstract
The present invention provides a voltage regulation method for DC micro-grid, which is suitable for a DC chain connected between the regenerated energy and the bidirectional converter. The method includes the following steps: calculating the capacitance of the bidirectional converter; recording the voltage variation of the DC chain from the first time to the second time; obtaining a current command changing amount according to the voltage variation of DC chain and the capacitance of bidirectional converter so as to further find the steady-state voltage level of DC chain; and, respectively calculating the current commands of DC chain at the second time and the third time according to the steady-state voltage level to adjust the steady-state voltage level for the DC chain to reach at the third time. When the DC loading is changed, the bidirectional converter can not only employ smaller capacitance to cover a large scope of voltage variation of DC chain, but also automatically balance the loading requirement based on the amount of operation power of the converter to maintain the stability and reliability of the system.