A control device and control method for an inverter cooling fan

Abstract

The invention discloses a control method for an inverter cooling fan. The method comprises the following steps: detecting the real-time temperature of all power devices of an inverter in the running process; selecting the maximum real-time temperature of all the power devices; if the maximum real-time temperature exceeds the set over-temperature value of each section and the time that the maximum real-time temperature continuously remains exceeding the set over-temperature value reaches the corresponding set delay value, increasing one step for PWM (Pulse-Width Modulation) duty ratio, and increasing the rotating speed of the fan; if the maximum real-time temperature is less than the set low-temperature value of each section and the time that the maximum real-time temperature remains being less than the set low-temperature value reaches the corresponding set delay value, decreasing one step for the PWM duty ratio, and decreasing the rotating speed of the fan; if both the aforementioned determining conditions are not met, maintaining the current rotating speed of the fan. The method is applied to the cooling of the power devices of the inverter and can solve the problems in the prior art, such as that the rotating speed of the fan frequently varies, the temperature reference value is not easy to reasonably set, the fan easily runs at over-temperature if the temperature varies a lot, and a plurality of preset temperature / rotating speed curves are provided and difficult to realize. The invention further discloses a control device for the inverter cooling fan.

Description

technical field [0001] The invention belongs to the field of fan control, and in particular relates to a control device and a control method of a DC fan for inverter heat dissipation. Background technique [0002] In small and medium power inverters, DC fans are usually used to dissipate heat from power devices to reduce their operating temperature and ensure the normal operation of the inverter. The speed control method of the current DC fan is pulse width modulation (PWM) control, and its control principle is: provide a square wave signal to the control line of the fan, and control the speed of the fan by adjusting the duty cycle of the square wave signal. [0003] The following methods are commonly used to control the speed of DC fans: one method is constant temperature control, which sets a desired temperature reference value, and through closed-loop control, automatically adjusts the duty cycle of the PWM signal according to the temperature reference value to maintain t...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a control device and control method for an inverter cooling fan, which is used for cooling the inverter power device, and can solve the problem of frequent changes in the fan speed and difficulty in setting a reasonable temperature reference value in the prior art. When the temperature change rate is large, it is easy to over-temperature operation, and there are many preset temperature / speed curves that are difficult to realize, etc.

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