摘要 |
An energization control device is provided to prevent rapid decrease of current which is flowing through each of phase coils of an electric motor. A time duration is divided into three stages which ranges from an initiation of the current supply to the phase coil to a termination of the current supply to the phase coil. At the first stage, the second stage, and the third stage, soft/hard chopping energization control, 0-volt energization, and duty chopping energization control, respectively, are made. Energizing the phase coil is made by way of a first switching element and a second switching element. At the first stage, depending on an actual current value being in excess of a target current value, either of or both of the first switching element and the second element are made OFF. At the second stage, while the second switching element is being made OFF, the second switching element is made ON. At third stage, while the second switching element is being made OFF, the first switching element is, at a duty cycle, made ON and OFF alternately in repetition.
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