Method and device for regulation of a rotary electrical machine for a motor vehicle

A regulation device (1, 2) for controlling a polyphase rotary electrical machine which device can bring control to said machine using a predetermined set value of a direct voltage (B+) of an on-board electrical network which is supplied by said machine, comprising:

• an analogue control block (10) having a periodic excitation current (+EXC, −EXC) with a duty cycle (RC) which is determined by a digital processing block (9), on the basis of an error voltage between said predetermined set value and said direct voltage (B+) of the on-board electrical network;
• a system (11) for making said digital processing block (9) electrically self-sufficient, said system (11) comprising voltage maintenance means, with a self-sufficient capacitor (110), for providing a self-sufficient supply voltage (V0) which supplies exclusively said digital processing block (9);
• and
• a self-sufficient control means (111) for controlling the self-sufficiency of the digital processing block (9) according to the amplitude of the self-sufficient supply voltage (V0), wherein said self-sufficient control means (111) comprise means (12) for stopping at least one clock (5) of said digital processing block (9) when said self-sufficient supply voltage (V0) is lower than a reference supply voltage (V1) of said digital block (9).