Patent ID: 8836270

Claim:
An inverter system comprising: a master inverter connected to a motor; and one or more slave inverters connected to the master inverter via a half-duplex communication line and each connected to the motor in parallel to the master inverter via a common communication node, wherein the master inverter includes: a driving unit configured to drive the motor based on a first PWM carrier and a first voltage command; and a communication unit configured to broadcast-transmit first data including a current command to the half-duplex communication line in synchronization with the first PWM carrier, each of the one or more slave inverters includes: a driving unit configured to drive the motor based on a second PWM carrier and a second voltage command; a communication unit configured to receive the first data through the half-duplex communication line and broadcast-transmit, in synchronization with the second PWM carrier at timing for avoiding reception timing of the first data, second data including an actual output current output from the slave inverter to the motor to the half-duplex communication line; and a phase adjusting unit configured to adjust, according to the reception timing of the first data, a phase of the second PWM carrier to match a phase of the first PWM carrier, and the master inverter further includes an amplitude adjusting unit configured to adjust, when the second data is received by the communication unit, amplitude of the first voltage command according to the received second data, so as to balance an actual output current output from the master inverter to the motor and an actual output current output from each of the one or more slave inverters to the motor.