Motor control apparatus

A motor control apparatus for converting a DC brushless motor into an equivalent circuit having a q-axis armature on a q-axis which is aligned with the direction of magnetic fluxes of field systems of the motor and a d-axis armature on a d-axis which extends perpendicularly to the q-axis, comprising:

• current detecting means for detecting currents flowing through armatures of the motor;
• actual current calculating means for calculating a q-axis actual current flowing through said q-axis armature and a d-axis actual current flowing through said d-axis armature from the currents detected by said current detecting means;
• current difference calculating means for calculating a q-axis current difference between a q-axis command current which is a command value for the current flowing through said q-axis armature and said q-axis actual current and a d-axis current difference between a d-axis command current which is a command value for the current flowing through said d-axis armature and said d-axis actual current;
• means for generating a d-axis command voltage which is a command value for the voltage applied to said d-axis armature and a q-axis command voltage which is a command value for the voltage applied to said q-axis armature in order to reduce said d-axis current difference and said q-axis current difference;
• means for controlling the currents flowing through the armatures of the motor depending on said d-axis command voltage and said q-axis command voltage;
• proportional term component generating means for carrying out a proportional process to multiply said d-axis current difference and said q-axis current difference by respective predetermined proportional gains to generate a d-axis proportional term component which is a proportional term component of said d-axis command voltage and a q-axis proportional term component which is a proportional term component of said q-axis command voltage;
• integral term component generating means for effecting an integrating process on said d-axis current difference and said q-axis current difference based on a predetermined integral gain to generate a d-axis integral term component which is an integral term component of said d-axis command voltage and a q-axis integral term component which is an integral term component of said q-axis command voltage;
• and
• command voltage generating means for generating said d-axis command voltage depending on the sum of said d-axis proportional term component and said d-axis integral term component, and said q-axis command voltage depending on the sum of said q-axis proportional term component and said q-axis integral term component;
• means for setting said integral gain to stabilize a system in which said d-axis current difference and said q-axis current difference are multiplexed, integrated, and inputted, with respect to a steady gain which approximates, including said proportional gains, the steady input-to-output relationship of said motor to which the voltage applied to said d-axis armature and the voltage applied to said q-axis armature are inputted and from which the current flowing through said d-axis armature and the current flowing through said q-axis armature are outputted.