Research On The Application Of XCP In Calibration System Of Electronic Control Diesel Engine

Electronic control unit (ECU) is the core of the Engine electronic control technology. In the developing process of the ECU, it is needed to do a number of calibration experiments to make the engine to achieve a good performance. To speed up the development progress of diesel engine's ECU and optimize the control parameters of the ECU and improve the working performance of engine, the paper designed and implemented a kind of reliable and efficient software of Calibration System of ECU,which was based on the control area network (CAN) bus.The calibration software mainly consisted of two parts:calibration software on PC and calibration software on ECU. It adopted the international advanced calibration protocol-XCP to realize the online calibration of MAP datas in the ECU and the real-time monitoring of variables and so on.The part of PC software was developped by C# language in Visual Studio 2008 platform, which had a friendly human-computer interface. It provided a calibration interface with easy operations of the calibration, an intuitive display manner and the capabilitie of a data real-time storage. The part of ECU software was completed in the CodeWarrior integrated development environment for the hardware platform of Freescale MPC5554. It mainly consisted of the XCP driver, CAN driver, the MMU memory management and so on. The functions of XCP driver were parsing the XCP command, processing the XCP command and uploading data, realizing the function of online calibration and monitoring. CAN Driver realized a reliable CAN communication with a high-speed, whose baud rate could be up to 1Mbit/s. MMU realized the mapping of ECU memory from the logical address to the physical address, which enabled the memory's online programming. Meanwhile, in order to enhance the scalability and reusability of software, the thought of modular design was used in the calibration software design.The tests of Calibration software were implemented on the test bench of DK4A diesel engine. The functional tests of calibration software of ECU and PC were carried out,and the entire system was calibrated and tested, calibration of the PID closed-loop control parameters of engine idle speed was given as an example. Values of the PID control parameteres were successfully calibrated:Kp=0.4, K1=0.2. At the same time, online calibration and real-time monitoring functions of the calibration software were also verified. The test results show that all the functions of the calibration software are operating normally, the calibration software meets the design requirements and has high practical value. The calibration software has been applied in the development of the diesel engine electronic control unit by Peteco Co., Ltd. in Hunan.