Electric fan speed governing control system and method

Abstract

The invention relates to a control system for automatically and manually adjusting the speed of an electric fan according to the ambient environment temperature and the maintaining temperature set by users. In an automatic speed control mode of the invention, the zero-cross detection circuit outputs a zero-cross voltage signal of the input voltage to a singlechip which outputs a control level to conduct controlled silicon after delaying a certain time by taking the signal as a reference point of time and utilizing fast switching property of the unidirectional controlled silicon. According to the result which is collected by a temperature sensor circuit by comparing the ambient environment temperature and the maintaining temperature set by users, the singlechip automatically adjusts the speed of the electric fan by changing the conduction angle of the unidirectional controlled silicon to automatically adjust the AC power output, so that the ambient temperature can be maintained at the maintaining temperature set by users. In a manual mode, the user can make a stepless speed regulation to the electric fan by using input keys and an output display circuit. The control system is stable in circuit, simple in structure and high in control precision.

Description

technical field [0001] The invention relates to a control system for automatic adjustment and manual stepless adjustment of the rotating speed of an electric fan. Background technique [0002] The electric fan controlled by the existing single-chip microcomputer can steplessly adjust the speed and turn on and off at regular intervals. The speed regulation module uses an analog circuit to control the conduction of several thyristors to achieve speed regulation. The circuit structure is complex and cannot be automatically controlled. Speed ​​function. Other electric fans on the market generally use gear switches to adjust the speed, and the timing function is realized by mechanical springs or potentiometers. Both of these methods will cause damage to components, short service life, and manual stepless speed adjustment cannot be realized. , can not meet the user's wind speed requirements. Because the temperature changes greatly at night, no one controls the speed of the elect...

AI Technical Summary

Problems solved by technology

[0003] In order to solve the problem that the existing electric fan cannot automatically adjust the speed according to the temperature change of the environment and cannot realize stepless speed regulation, the present invention provides a digital control technology that can automatically adjust the speed of the electric fan. The ambient temperature value sent back by the temperature sensor automatically adjusts the speed of the electric fan to maintain the ambient temperature value at the temperature value set by the user. It can also realize the functions of stepless speed regulation, timing on and off according to the user's key input

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