Real-time closed-loop adjustment control method for single-phase brushless DC motor within power factor angle

Abstract

The invention discloses a method for controlling a single-phase brushless direct-current motor by real-time closed-loop adjustment of an inner power factor angle. When the single-phase brushless direct-current motor operates under different working conditions, phase current can have lag at different phase angles under the action of winding inductance, the inner power factor angle is calculated inreal time according to the phase difference between a Hall signal and the phase current, real-time closed-loop adjustment of the inner power factor angle is finished by controlling phase of phase voltage, and high-efficiency operation of the motor is realized on the basis. By designing a specific phase current sampling mode, the complete cycle of the phase current is obtained, then the inner powerfactor angle is calculated in real time, closed-loop adjustment of the inner power factor angle is finished, so that the inner power factor angle can be kept at zero all along when working conditionssuch as rotating speed, load and the like of the motor change, the tedious process for obtaining conduction angle under the different working conditions through many experiments is avoided, efficientoperation under any rotating speed and load can be guaranteed, and the motor has higher capacity to adapt to working condition changes.

Description

technical field [0001] The invention relates to a method for real-time closed-loop adjustment and control of a single-phase brushless DC motor within an internal power factor angle. Background technique [0002] Under the situation that high-efficiency and energy-saving requirements are put forward for electromechanical products, some applications originally driven by single-phase asynchronous motors have been replaced by low-cost permanent magnet motors with high power density and high efficiency. Single-phase brushless DC motor, also known as "single-winding brushless DC motor", has the advantages of simple structure, easy processing and manufacturing, less power tubes required, simple control circuit, and low cost. In some low-cost, low-starting torque , Low-power equipment that does not require high motor performance, such as fans, water pumps, etc., have been widely used. However, with the improvement of performance requirements in some applications, the operating effi...

AI Technical Summary

Problems solved by technology

If the current phase is not adjusted, efficient operation in a wide speed or wide load range cannot be achieved

In the traditional control method, a large number of experiments are used to measure the leading conduction angle required by the single-phase brushless DC motor at different speeds and different loads, and store it in the controller. This method is too cumbersome and the accuracy is not high. When changing, it is likely to need to re-measure the parameters, which cannot well meet the different applications of specific motors

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