Sensorless Drive System of BrushLess DC motor for bus air conditioner cooling fan

摘要

The present invention relates to a sensorless driving system of a BLDC motor for a bus air conditioner cooling fan. The first aspect of the present invention is composed of a control unit 10 employing a microcontroller 11 of Microchip company dsPIC33FJ64MC802 and a 180W BLDC motor 20 having a rating of 24 [V] / 0.49 [Nm] In a sensorless drive system for a bus air conditioner cooling fan BLDC motor that drives a bus air conditioner cooling fan through drive software and hardware configuration, the microcontroller 11 employs a counter-electromotive force zero crossing technique and uses a zero crossing detection method The variable threshold voltage point used for detecting an event is obtained as a virtual neutral point voltage which is an average value of the counter electromotive force signals. The neutral point voltage obtained by calculating the detected counter electromotive force signals by A / D conversion and software is compared with the counter electromotive force signals, In providing a sensorless drive system of a BLDC motor for a bus air conditioner cooling fan that determines an event All. Accordingly, it is possible to accurately detect the zero crossing event in the back electromotive force signal which is the core of the sensorless control of the BLDC motor, thereby providing an effect of improving the reliability for driving the bus air conditioner cooling fan. Further, in order to solve the problem that the bus air conditioner system composed of the middle and large type is constituted by a heavy structure and causes a problem in the fuel consumption of the bus and the rigidity of the bus itself, This can be solved by using a zero crossing detection method which requires only a few external components (resistive elements). In addition, the present invention relates to an advanced bus air conditioner system based on a BLDC motor, an improvement of energy efficiency and fuel economy of a bus air conditioner system, development and dissemination of eco-friendly technology by low noise and low vibration, A unique technology of the fan motor and the drive control system can be secured.