POLYPHASE MACHINE CONTROL METHOD AND DEVICE Russian patent published in 2014 - IPC H02M7/493 

FIELD: electricity.

SUBSTANCE: polyphase machine (30) is controlled by means of parallel multiphase inverters (10₁, 10₂). Each inverter comprises branches (10_1a, 10_1b, 10_1c; 10_2a, 10_2b, 10_2c) in quantity equal to a phase number in the electrical machine, and the inverters are controlled by pulse-width modulation (PWM). In response to the failure detection in the inverter branch (10_2a) this branch is disconnected, and the respective phase is supplied through the other or any other branch of the inverter (10_1a). PWM control is changed in order to ensure conducting state continuously and without reswitching of power breakers in this or any other branch of the inverter (10_1a) when absolute value of current strength (I_a) in the tested phase is equal or exceeds the threshold making up 80-120% of $$\frac{n-1}{n}{I}_{\max }$$ , where n is a number of inverters and I_max is maximum current strength of the phase.

EFFECT: making possible generation of sinusoidal voltage in essence at each phase of the machine and prevention of power breakers overvoltage so that in case of their failure they are able to commutate currents with larger amplitude than at normal operation.

9 cl, 9 dwg