Patent ID: 6346785
Filing Date: 2002-02-12
Classification: H02P

Abstract:
A driving control system for electric motors with N coils, N being at least three, including: a power source (20) in direct current; an inverter (30) having commutation arms with the opposite ends connected to the power source and each including switch means, each commutation arm being medianly connected to a respective coil; a position sensor means (50) connected to the coils; and a control unit (40), operatively connected to the position sensor means (50) and to the switch means, in order to operate the latter as a function of the signals received from the position sensor means (50), characterized in that the inverter (30) has Nâˆ’1 commutation arms and the power source (20) has, between positive (21) and negative (22) terminals of equal voltage, a median terminal (25), of null voltage, to which is directly connected a first coil (11) of the electric motor (10), the inverter (30) having a first switching condition of the switch means, in which the first coil (11) is subjected to a null voltage, while two other coils are subjected to a determined voltage value, and a second switching condition of the switch means, in which the first coil (11) and any of said other coils are subjected to a voltage value equivalent to half the determined voltage value and corresponding to the nominal voltage, the control unit (40) determining to the switch means, the latter being in one of the first and second switching conditions, a switching frequency and a switch conduction period, which are defined so that the voltage value which is effectively applied to the coils is that one corresponding to the speed and torque required to the electric motor (10), independently from the switching condition of the switch means.