Color Scheme of PWM Vector Control for 3-Phase AC Machines

The purpose of this paper is to describe the PWM voltage vectors of the 3-phase AC motor drives with RGB color code, realize the color scheme for the vector control, so as to provide a new and visible approach to understanding the vector control principle. RGB color code can be regarded as a set of three-phase coordinate values and it forms a color vector, which is consistent with the vector addition rule. When a variable in the motor vector control is represented with a set of three-phase coordinate values, after adding the corresponding zero sequence components and multiplying the corresponding coefficient, it corresponds to RGB color code. When the three-phase to two-phase coordinate transformation with the color code is realized, the specific location on the plane where the color vector locates is obtained. In this way, the correspondence between the motor vector control variable, the RGB color code and the location on the plane is achieved. Then, the color change process on the plane visualizes the three-phase AC motor PWM vector control process.