Patent ID: 9124175
Filing Date: 2015-09-01
Classification: H02M,H02P

Abstract:
1. A load drive control device for controlling driving of an inductive load, the load drive control device comprising: a switching section provided in an energizing path of the inductive load, the switching section flowing an electric current to the inductive load when the switching section is ON; a pulse signal generating section for driving the inductive load by generating pulse signals with a duty ratio at a drive frequency and by supplying the pulse signals to the switching section, wherein the drive frequency is predetermined; an actual current value detection section for detecting an actual current value of the inductive load; a feedback setting section for setting the duty ratio for feedback based on a deviation between a target current value of the inductive load and the actual current value detected by the actual current value detection section so that the actual current value follows the target current value; a drive frequency setting section for setting the drive frequency of the pulse signals; a detection setting section for setting the duty ratio for detection, the duty ratio for detection being provided for detecting a natural vibration frequency of the inductive load; a natural vibration frequency setting section for setting the natural vibration frequency of the inductive load based on the actual current value that is detected when the duty ratio for detection is set; and a selection section wherein: the detection setting section sets the duty ratio for detection, which is different in duty ration value from the duty ratio for feedback used by the pulse signal generating section before the duty ratio setting section switches over from the feedback setting section to the detection setting section; and based on the natural vibration frequency detected, the drive frequency setting section sets the drive frequency so as not to generate resonance.