| 摘要 |
PROBLEM TO BE SOLVED: To provide a trusty motor coil current detecting circuit by dissolving the delay of the trailing of the motor coil current to a current command value, and removing the switching noise, and a trusty current control type of motor driving circuit using that circuit. SOLUTION: A current detecting circuit 8 is composed of shunt resistors Rs1, Rs2, and Rs3 for detection of currents at power run and regeneration, a diode D1 connected in series to these, flywheel diodes D2 and D3, and an adder circuit 81 for detected voltage of shunt detectors. Then, in a motor driving circuit, a control circuit 4 controls applied current in a motor coil 7 so that no difference is detected at all times between the command stored in a storage device 2 and a detected current signal. Further, the control circuit 4 is constituted such that, on exciting a motor coil, a logic circuit 5 simultaneously actuates PWM-driven switching element based on an applied-current command signal from the control circuit 4 and a current direction command signal from the storage device 2 at both source and sink sides of H-bridge circuit. |
