Advanced Aircraft Electrical System, The Key Technologies Of The Main Processor Of The Computer Control And Management Systems

As the rapid advancement of computer and electronic technology, distributed electrical loads auto-management becomes a new direction in advanced aircraft electrical system. As the kernel of aircraft electrical system, Power System Processor controls and manages the whole aircraft electrical system. It implements electrical load scheduling and management, system fault process and fault recovery, system rebuilding and save the history data.Power System Processor is a typical embedded real-time multi-tasking system, which requests high capability in real-time response, reliability and the adaptation to environment, so the advanced software and hardware platform includes Real-time Operation System VxWorks and PC 104 486DX and effective real-time analyse and design methods are invoked in this project. In the design and implement of system tasks, the key techniques are realized as following: setting the task model and choosing the schedule algorithm via hiberarchy model, improving the Rate-monotonic Scheduling by means of the theory about mathematical statistics;creating real-time memory database including its storage structure and search algorithm to ensure the integrality and consistency of the data in database;developing the CAN driver in Vx Works which supports re-send and timeout control to improve the reliability of the real-time communication, adopting a simple stop-wait protocol to actualize the compages of short frames;setting the Electrical Load Equation and its parse algorithm to implement load scheduling and management;invoking True Flash File System to save configuration table of the loads and the history data.The last part of this paper discusses limitation of the traditional reliability algorithm for analyzing the real-time software, and then raises a proper model to calculate the reliability of real-time software. It introduces the measures to improve the performance of real-time response, reliability and the adaptation to environment. At last, the capacity and testing result of this software is figured out.