SUBSIDIARY POWER SOURCE FOR BIDIRECTIONAL POWER SUPPLY

An auxiliary power source for bi-directional power supply is disclosed by the present invention, which includes a bi-directionally isolated converter (21), a first non-isolated converter (22), a second non-isolated converter (23), a first merging circuit selector (24), and a second merging circuit selector (25), where the first merging circuit selector (24) is connected to a primary voltage line (26), the bi-directionally isolated converter (21), and the first non-isolated converter (22), and the second merging circuit selector (25) is connected to a secondary voltage line (27), the bi-directionally isolated converter (21), and the second non-isolated converter (23). In the auxiliary power source for bi-directional power supply according to the embodiments of the present invention, only one bi-directionally isolated converter (21) is required.