Patent ID: 9065363
Filing Date: 2015-06-23
Classification: H02P

Abstract:
1. A method for starting a single-phase synchronous electric motor comprising a permanent magnet rotor and a stator provided with windings connected to an electrical grid by means of a switch; said method comprising the following steps: a first starting attempt in which the windings are fed in current with one or more first starting impulses that are generated only during the half-periods of a first polarity of the voltage of the electrical grid; a first control step in which it is detected whether a starting condition has been obtained in the course of the first starting attempt; in case said first control step does not detect that the starting condition has been obtained within the term of the first starting attempt, a second starting attempt in which the windings are fed in current with one or more second starting impulses that are generated only during the half-periods of a second polarity, the opposite of the first polarity, of the voltage of the electrical grid; wherein the first starting impulses are configured in number and intensity in such a way that they start the rotor overcoming the cogging torque if it finds itself in a first rest position, and in such a way as to not change the position of the rotor if it finds itself in a second rest position.