Patent ID: 7629755

Claim:
An apparatus for controlling a secondary battery, comprising: a motor driving circuit receiving supply of electric power from a secondary battery to drive a motor; battery temperature obtaining means for detecting or estimating a battery temperature of said secondary battery; and a control circuit controlling said motor driving circuit such that output torque of said motor conforms to requested torque, wherein said control circuit includes first control means for operating said motor at a first operation point that requires a motor driving current of a first current amplitude for generating said requested torque, second control means for operating said motor at a second operation point that requires a motor driving current of a second current amplitude greater than said first current amplitude for generating said requested torque, and switching means for alternately switching between said first control means and said second control means for execution, when said battery temperature is lower than a prescribed threshold temperature, said first control means exerts feedback control of said motor driving current using a first current instruction that is constituted of said first current amplitude and a first current phase and that provides said first operation point, said second control means exerts feedback control of said motor driving current using a second current instruction that is constituted of said second current amplitude and a second current phase and that provides said second operation point, and said switching means alternately switches between said first current instruction and said second current instruction in the feedback control of said motor driving current.