PURPOSE: To enable brake control conformable with the characteristic of control system by combining two types of brake operation out of generative brake operation, reverse brake operation and regenerative brake operation in predetermined time shared timing.

CONSTITUTION: When brake control is performed, a PWM signal is pulled high when a rotary direction control signal CW has a high level and a rotary direction control signal CCW also has a high level during forward drive operation, and current is fed in the direction of an arrow (a) in order to convert the electrical energy through the resistance component in the circuit into thermal energy which is then dissipated thus carrying out generative brake operation. When the rotary direction signal CW has a high level and the rotary direction control signal CCW also has a high level, the PWM signal is pulled low to feed current in the direction of an arrow (b) and return the generated power to the power source thus carrying out regenerative brake operation. During reverse drive operation, brake control is carried out by combining same signals as those in case of forward drive operation.