To provide a motor controller which can be downsized at low cost by simplifying the switch constitution and can be used for both rush current suppressing treatment and regenerative electric power treatment with one resistor.
A switch control circuit 12 connects the common terminal and the terminal (b) of a relay 6 with each other at suppression of a rush current and suppresses the rush current with a resistor 7, and when the terminal voltage of a smoothing capacitor 3 reaches a specified value or over, it connects the common terminal with an (a) terminal. At regenerative electric power processing, a regenerative power transaction circuit 9 is turned on and regenerative energy is treated via the resistor 7, and when the terminal voltage of the smoothing capacitor 3 comes to a specified value or below, the regenerative power transaction circuit 9 is turned off, and the regenerative energy is treated via the resistor 7 and a diode 8.
Tomoyasu Sakaguchi
Hiroki Naito