A propulsion system (100, 200, 300) comprising: an electric drive; a direct current link (118, 120) electrically coupled to the electric drive; a first energy storage system electrically coupled to the electric drive, the first energy storage system comprising at least a battery and a power energy storage device; a second energy storage system, wherein a positive terminal of the second energy storage system is electrically coupled to the electric drive through the DC link (118, 120) and a negative terminal of the second energy storage system is coupled in series with a positive terminal of the power energy storage device; and a multi-channel bi-directional boost converter coupled to the first energy storage system and to the second energy storage system, characterized in that: the series connection between the positive terminal of the power energy storage device and the negative terminal of the second energy storage system are connected with the multi-channel bi-directional boost converter at the low voltage side of the multi-channel bi-directional boost converter; the battery and the power energy storage device are coupled together on the low-voltage side of the multi-channel bi-directional boost converter; a negative terminal of the battery and a negative terminal of the power energy storage device are coupled to each other via a first bus, and a positive terminal of the battery is coupled to a second bus which is a positive bus that connects through an inductor to a first channel of the multi-channel bi-directional boost converter on the low voltage side of the multi-channel bi-directional boost converter; and the positive terminal of the power energy storage device is coupled to a third bus, which is coupled through an inductor on the low-voltage side to a second channel of the multi-channel bi-directional boost converter. an electric drive; a direct current link (118, 120) electrically coupled to the electric drive; a first energy storage system electrically coupled to the electric drive, the first energy storage system comprising at least a battery and a power energy storage device; a second energy storage system, wherein a positive terminal of the second energy storage system is electrically coupled to the electric drive through the DC link (118, 120) and a negative terminal of the second energy storage system is coupled in series with a positive terminal of the power energy storage device; and a multi-channel bi-directional boost converter coupled to the first energy storage system and to the second energy storage system, characterized in that: the series connection between the positive terminal of the power energy storage device and the negative terminal of the second energy storage system are connected with the multi-channel bi-directional boost converter at the low voltage side of the multi-channel bi-directional boost converter; the battery and the power energy storage device are coupled together on the low-voltage side of the multi-channel bi-directional boost converter; a negative terminal of the battery and a negative terminal of the power energy storage device are coupled to each other via a first bus, and a positive terminal of the battery is coupled to a second bus which is a positive bus that connects through an inductor to a first channel of the multi-channel bi-directional boost converter on the low voltage side of the multi-channel bi-directional boost converter; and the positive terminal of the power energy storage device is coupled to a third bus, which is coupled through an inductor on the low-voltage side to a second channel of the multi-channel bi-directional boost converter. the series connection between the positive terminal of the power energy storage device and the negative terminal of the second energy storage system are connected with the multi-channel bi-directional boost converter at the low voltage side of the multi-channel bi-directional boost converter; the battery and the power energy storage device are coupled together on the low-voltage side of the multi-channel bi-directional boost converter; a negative terminal of the battery and a negative terminal of the power energy storage device are coupled to each other via a first bus, and a positive terminal of the battery is coupled to a second bus which is a positive bus that connects through an inductor to a first channel of the multi-channel bi-directional boost converter on the low voltage side of the multi-channel bi-directional boost converter; and the positive terminal of the power energy storage device is coupled to a third bus, which is coupled through an inductor on the low-voltage side to a second channel of the multi-channel bi-directional boost converter.