Electrical system

An electrical system comprising:

• a DC source configured to provide a DC electrical power, a voltage across the DC source being VIN;
• a bus electrically coupled to the DC source, the bus comprising a load;
• an isolated DC-DC converter having an input side coupled in parallel with respect to the DC source and an output side coupled in series with respect to the DC source and the bus, wherein a voltage across the output side of the isolated DC-DC converter is VOUT DC-DC;
• a switching arrangement electrically coupled to the isolated DC-DC converter, the DC source, and the bus;
• and
• a control system;
• wherein,
• the input side of the isolated DC-DC converter is configured to receive a fraction of the DC electrical power provided by the DC source, the fraction being less than unity;
• the control system is configured to operate the switching arrangement to selectively configure the electrical system in at least one of a voltage increase mode and a voltage decrease mode;
• in the voltage increase mode, the switching arrangement of the electrical system is configured to couple the output side of the isolated DC-DC converter to the DC source and the bus to supply a voltage to the bus corresponding to VIN+VOUT DC-DC that is an addition of the voltage across the DC source and the voltage across the output side of the isolated DC-DC converter;
• and
• in the voltage decrease mode, the switching arrangement of the electrical system is configured to couple the output side of the isolated DC-DC converter to the DC source and the bus to supply a voltage to the bus corresponding to VIN−VOUT DC-DC that is a difference between the voltage across the DC source and the voltage across the output side of the isolated DC-DC converter.