METHOD FOR PHASE CONTROL OF INDUCTION MOTOR Russian patent published in 2010 - IPC H02P23/08 H02P27/04 

FIELD: electricity.

SUBSTANCE: in method for phase control of induction motor with short-circuited rotor supplied from power converter at each moment of time frequency of rotor rotation f₃ is measured or determined, rotor rotation frequency f_z is specified, as well as electromagnet torque M_z value of induction motor stator windings voltage amplitude is determined, required for provision of specified electromagnet torque M_z at current value of rotor rotation frequency f₃, additionally angle of rotor rotation is measured, electric angle corresponding to angle of rotor rotation is identified at the interval of 0÷2π, sliding frequency is specified as identical in sign with specified electromagnet torque M_z, sliding phase value is identified, integrating frequency of sliding at the interval 0÷2π, value of induction motor stator windings supply voltage phase is determined as sum of sliding phase value and value of measured electric angle of rotor rotation, above specified amplitude and phase of induction motor stator windings supply voltage are generated with the help of power converter.

EFFECT: expanded range of stable operation of simple-to-implement systems up to zero frequencies of rotation, increased accuracy of control and preservation of motor overload capacity in the whole range of rotation frequencies, increased efficiency of drive.

4 cl, 1 dwg