Development Of Protection And Control Devices In Power System Based On Embedded System

Power system protection and monitoring device is an important infrastructure to ensure the safe and stable operation of power grid. The construction of smart grid put forward to more and more requirements on device performance. In view of the current insufficiency in this field, the thesis adopts advanced embedded software and hardware technology, and develops a new platform for protection and monitoring device.A new hardware platform based on dual processor architecture (MCU&DSP) is designed. MCU (Micro Control Unit) module accomplishes the management and communication function. The hardware platform adopts the floating-point DSP (Digital Signal Processor) as data co-processor to fulfill phasor calculation and protection function. Data exchange through the HPI (Hardware Platform Interface)) interface between the MCU and DSP. The thesis also describes the functional design of key module, including main processor module, AC analog acquisition module, temperature acquisition module, digital input/output module, display module and Ethernet communication interface.The thesis designs the software platform based on VxWorks real time multitask operating system. In accordance with the software design methods of the functional hierarchical, the thesis develops the network driver for AX88796chip. In order to meet the quick start-up requirements of protection and monitoring function, the thesis modifies the loading sequence of VxWorks network equipment, and separates the END(Enhanced Network Driver) driver loading process from the system boot process. Furthermore, the LCD module driver based on RA8835A controller and the menus display software based on list structure are designed completely, which are easy to implement the replacement and upgrade of the LCD module. The t also develops the DSP’s two-level Bootloader function with FLASH boot mode, and compiles the lnk.cmd file on the basis of the application requirements and hardware configuration. By calling floating-point library of TMS320C6713, the efficiency of digital signal processing algorithms is enhanced rapidly.The interrupt and task resources are allocated reasonably according to the different requirements of protection, monitoring and control functions. The thesis studies the principle and performance of a variety of electrical calculation method, such as whole cycle integral algorithm, whole cycle Fourier algorithm and fast square root algorithm. To solve the problem of digital input information’s misinformation or missing, the thesis improves software filtering strategy and confirmation criterion for input dithering by the means of increasing the judging number and prolonging delay time.At last, the thesis sums up large number of test results, especially about the device type test performance. Detected by the third-party testing organization, the device’s performance fully meets the national standard and industry standard and achieves the expected design goal.