Abstract: A method for controlling a synchronous motor that has a stator and a rotor, comprising: correcting the frequency, phase, and values of the motor's feeding voltages, as well as the value of its magnetic flux as a function of the angle between stator and rotor magnetic fields vectors of said synchronous motor, wherein said angle derivative an angular speeds mismatch between said vectors.

Abstract: An object of the present invention is providing permissible values of start currents with sufficiently high start torque ensuring the possibility of the start of a loaded motor, the smoothness of the motor's start, without spikes and fluctuations of the currents, voltages and torques. The other objects of the proposed device are simplicity, reliability and economic efficiency. The proposed method of an induction motor start includes an acquisition of two components of the voltage, feeding the motor. The both components have the different controlled frequencies and root mean square values. The proposed device for an induction motor start comprises two channels forming signals, which create two corresponding components of the motor's feeding voltage.

Abstract: An object of the present invention is providing permissible values of start currents with sufficiently high start torque ensuring the possibility of the start of a loaded motor, the smoothness of the motor's start, without spikes and fluctuations of the currents, voltages and torques. The other objects of the proposed device are simplicity, reliability and economic efficiency. The proposed method of an induction motor start includes an acquisition of two components of the voltage, feeding the motor. The both components have the different controlled frequencies and root mean square values. The proposed device for an induction motor start comprises two channels forming signals, which create two corresponding components of the motor's feeding voltage.