Control apparatus for rotary electric machines

A control apparatus for a rotary electric machine with terminals receiving power from a DC power supply with positive and negative output terminals, comprising;

• a DC-AC converting circuit provided with serially connected circuits each having a high-potential-side switching element and a low-potential-side switching element, the high-potential-side and low-potential-side switching elements selectively connecting the terminals of the rotary electric machine to the positive and negative output terminals of the power supply for controlling a controlled variable of the rotary electric machine;
• a connecting/disconnecting circuit arranged to be electrically opened and closed between the DC-AC converting circuit and the power supply to electrically connect and disconnect an electric path connecting both the DC-AC converting circuit and the power supply;
• determining means that determines whether or not the high-potential-side and low-potential-side switching elements have a malfunction;
• and
• failsafe performing means that opens the connecting/disconnecting circuit and turns on both the high-potential-side and low-potential-side switching elements residing in a part of the serially connected circuits when it is determined by the determining means that the high-potential-side and low-potential-side switching elements have the malfunction such that the turned-on high-potential-side and low-potential-side switching elements realize a short-circuit state therein.