Power supply system supplying an electrical load via a polyphase voltage and an auxiliary network via a homopolar component of the voltage, and related electrical installation

An electrical power supply system comprising:

• a main electrical power supply system configured to generate, from a main electrical network, at least one polyphase voltage in order to supply at least one electrical load;
• each electrical load having a winding for each phase of the respective polyphase voltage, the windings being connected together at a midpoint in a star connection;
• an auxiliary power supply system configured to supply power to an auxiliary electrical network, the auxiliary electrical network including a first and a second power supply terminals;
• wherein the main power supply system is configured to generate the at least one polyphase voltage with at least one non-zero homopolar component, and
• the auxiliary power supply system comprises a connection module configured to connect the first power supply terminal to the midpoint and the second power supply terminal to a reference point, for supplying the auxiliary electrical network via the at least one non-zero homopolar component, the respective homopolar component coming from the midpoint.