To provide a phase controller, which is capable of a high resolution phase control while lowering the resolution of a rotary sensor and thereby reducing the cost but increasing the reliability of the sensor.
A sensor digital signal θ output from a rotary sensor of a resolution (n) is multiplied by a weight factor (m) and then is added with a phase control digital signal β. According to the calculation result (θ×m+β), the waveform data is read out form a waveform storing means 16. In the waveform storing means 16, n (the resolution of the rotary sensor) multiplied by m (the weight factor) number of waveform data are stored as the waveform data portion corresponding to one cycle. By this method, even if the resolution of the rotary sensor is low, phase control can be done with high resolution which is the weight factor times as high as that of the rotary sensor, in other words, a phase control can be done with a high resolution while lowering the cost of the rotary sensor and increasing the reliability.
KONDO YASUHIRO
ICHIUMI YASUFUMI
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