Driving circuit of vehicle cooling fan and vehicle heat dissipation system

By using a relay-free switch control unit and a two-stage delayed soft-start circuit, the problems of induced current and surge current in the cooling fan system are solved, enabling reliable operation of the cooling fan and protection of the capacitor, thereby improving the stability and lifespan of the system.

CN114590122BActive Publication Date: 2026-06-09JOHNSON ELECTRIC GUANGDONG CO LTD
View PDF 2 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
JOHNSON ELECTRIC GUANGDONG CO LTD
Filing Date
2020-12-07
Publication Date
2026-06-09

AI Technical Summary

Technical Problem

In existing automotive cooling fan systems, the cooling fan is prone to reversing, generating induced electromotive force and induced current, which can lead to electronic component failures. Furthermore, relays are easy to solder and large electrolytic capacitors are susceptible to surge current impacts, affecting their lifespan.

Method used

A relay-free switching control unit is adopted, which reduces inrush current and avoids electrolytic capacitor impact through two-stage delayed soft-start switching transistors. The switching control circuit composed of MOSFETs and transistors ensures normal motor start-up and shutdown.

Benefits of technology

This effectively avoids damage to capacitors caused by relay failures and surge currents, ensures reliable operation of the cooling fan, and improves system stability and lifespan.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN114590122B_ABST
    Figure CN114590122B_ABST
Patent Text Reader

Abstract

The application provides a driving circuit of a vehicle cooling fan, which is used for driving a motor of the vehicle cooling fan, comprising an inverter circuit and an electrolytic capacitor connected between two power supply terminals, and a switch control unit, the switch control unit comprising a first and a second resistor, a first and a second capacitor, and a first and a second switch tube; the control end of the first switch tube receives a level representing the ignition switch state of the vehicle, the first conduction end is connected with an electronic control unit, and the second conduction end is connected with the control end of the second switch tube; the first conduction end of the second switch tube is connected with a power supply module, and the second conduction end is connected with a positive power supply terminal; the first resistor is connected between the first conduction end of the second switch tube and the control end of the first switch tube; the first capacitor is connected between the control end and the first conduction end of the first switch tube; and the second resistor and the second capacitor are connected in series between the second conduction end and the control end of the second switch tube.
Need to check novelty before this filing date? Find Prior Art