| 摘要 |
An auxiliary power supply device that can always supply stable auxiliary power at the time of using an auxiliary power source and an electric power steering device employing the auxiliary power supply device are provided. In the auxiliary power supply device 1 including a discharge circuit 15 selectively constituting a state where a motor 5 is supplied with power from only a battery 7 and a state where the motor 5 is supplied with power from a power source in which an auxiliary power source 10 is connected in series to the battery 7 by PWM control, when the power consumption of the battery 7 is greater than an upper limit, a control circuit 20 is provided which controls the power consumption to return to the upper limit by performing an electric power feedback control using a duty as an amount of operation at the time of turning on and off switching elements 12 and 13 by a PWM control on the basis of the difference. |
