Abstract: A robot distributed control system includes a host controller issuing a first command and a plurality of communication controllers connected to the host controller in a tree-structured manner. The communication controller obtains a control parameter by interpreting the first command, or issues a second command by executing an application program in response to the first command and then obtains a control parameter. In either case, the control parameter is output from the communication controller to the motor controller by which a plurality of motors are controlled.

Abstract: When power supply to a high voltage transformer starts, the phase &thgr; of the voltage of an AC power source when power supply to the high voltage transformer is stopped last time is referred to. In accordance with the value of the phase &thgr;, the phase of the voltage of the AC power source when power supply to the high voltage transformer starts is determined, so that the peak value of the rush current in the high voltage transformer is minimized.