Design And Development Of The Auxiliary Power Unit’s Simulation And Automatic Test System

In this paper, design and development of simulation and atuomatic test platform in the background of a certain type of Auxiliary Power Unit.Auxiliary power unit (abbreviated APU) is essentially a small gas turbine engine. It can provide a pressurized air source and the shaft power to start the main engine-driven hydraulic pump. It can also driven hydraulic pumps and generators for aircraft to provide spare hydraulic source and power, and to provide air to the cabin air conditioning system. Because the APU equipment’s structure is complex and expensive, it can not always use real system to test its performance and parameters. This is not conducive to develop and improve the system, also fault diagnosis. Therefore, it is very important to developt and design a simulation and atuomatic test platform that can replace the real device to complete APU features and operating characteristics simulating.This paper elaborated the design and development of the APU system’s simulation and atuomatic test platform.First introduced the feature, characteristics and development status of the Automatic Test Systems. Then according to the APU’s functional structure and the test platform’s control requirements, an overall scheme of the system is proposed. This paper also elaborated how to build the APU system’s simulation model that based on MATLAB/ SIMULINK, and how to build a modular hardware architecture that based on PXI bus, how to use VeriStand software to complete the master software development.According to the needs of the system test experiments, it can configure the experimental configuration.It use Labview software to build the test platform’s display control interface. In addition to providing a virtual environment for simulation and test, the test platform also can provide simulation interfaces of the APU and the ECU, in order to connect with the real equpment or emulator. Through the actual running and debugging, the correctness and reliability of the test platform are verified.The system also provides fault injection capabilities which made the APU fault simulation and diagnosis possible.This design of simulation test platform meets the aviation industry standards.The product has been put into practical application, and is currently in the experimental stage.It has achieved the expected results.