Research On Digital Control Platform For Reactive Power Compensation Based On DSP And ARM9

Nowadays digital control technology has been widely used in power electronic devices, so how to design reliable and practical digital contol system according to the requiements of devices becomes very important throughout the design of power electronic equipements. With magnetic valve controlled reactor as the control object, this paper lauches a digital control hardware platform, developes a complete software system, realizes digital control of reactive power compensation and fulfills interface-friendly human-machine interaction system. The digital control platform performs well in portability and scalability, at the same time, it's practical, reliable, and worth popularizing.This paper firstly introduces the significance of reactive power compensation and the development of its related equipment, and then makes a deep theoretical research on the reactive power compensation principle of magnetic valve controlled reactor (Magnetic-valve Controlled Reactor-MCR). The control characteristics of MCR are finally obtained by the theory analysis and MATLAB simulation, namely, the corresponding relationship between thyristor trigger angle and MCR working current, and as a basis for establishing the MCR open-loop control strategy.With MCR as the control object, the digital control platform hardware design selects DSP and ARM, respectively, as the core for MCR control system and human-machine interface system. DSP subsystem also includes power supply circuits, reset circuits, storage devices, external sampling circuits and thyristor trigger pulse generation circuit, etc; ARM human-machine interface also includes storage systems, liquid crystal display devices, serial interfaces, Ethernet and USB support. Based on DSP interrupt service programming, the software designs and implemented voltage and current sampling, dq reactive power algorithms, trigger pulse generation and fault handling, while human-machine interface system is developed based on ARM programming, including the establishment of cross-compiling environment, Linux kernel, Bootloader and file system porting, NFS debugging, as well as MiniGUI application development. Finally, simulation experiment is performed base on the digital control platform and the trigger pulse with particular trigger angles is generated.