Semi-physical Simulation Technology Research Of Diesel Electronic Control System

The electronic control technology is one of the major directions of the diesel research. The electronic control technology is also the effective way to improve the power performance, economy performance, reliability performance and the emissions performance. The level of the electronic control has become a advanced symbol of the diesel. The diesel electronic control technology is developing from the single functions to the multi-objective comprehensive control. With the strengthen of the electronic control system functions and the complex of the structure, the electronic control system of the diesel is difficult to develop, the development cycle is length, the cost is high and the test is difficult. The integrated simulation technology was used to research the diesel electronic control system which is from the functional design, the rapid control prototyping, the code generation to semi-physical simulation. It is necessary that the V model development process was used to solve the development difficulty of the diesel electronic control system.For the technical difficulty of the development, debugging and testing of the diesel electronic control system, on basis of the referring to the related technical information and analyzing the semi-physical simulation technology status and development trend, the semi-physical simulation technology of the marine diesel electronic control was researched. The major works are as follows:1. The experiments matching to machine of the marine diesel control system included I/O channel debugging, system function testing and parameter optimization. The experiments have a lot of disadvantage, such as the long cycle, the high cost, the high-risk and the limited conditions.According to the special requirements of the diesel control system for multi-input and output, high-precision and high real-time, the mean-value and thermodynamic principle was used to set up the diesel model to meet the control demands of the many objectives and the real-time. The burning chemical reaction thermal of marine diesel is calculated application of Arrhenius method so as to achieve the accuracy calculation of the combustion torque and meet the control demand of cut-off cylinders and array, this guaranteed the accuracy and the real-time of the model for the purpose of researching the control system. The turbine and compressor equivalent parameters were calculated. The characteristics expressed by equivalent parameters possess the best comparability and versatility.2. The modularization method is chosen to establish a complete diesel simulating model of the many input and output and power transmission system model of the ship. The model code was downloaded to the dSPACE real-time simulation platform, the operation and calculation of the model was carried on by the dSPACE/PPC controller board. Based on the researching need of the diesel ECS, the appropriate simplify, experimental data configuration, module division and the data process of the multi-cylinder technology were taken during modeling, so that the model is high accuracy, good real-time and high universality.3. Based on the control system researched, the diesel control system modeling and simulation and the performance optimization of the diesel were researched. the paper has researched the start intelligent control, the match optimize control between the fuel system and the charger system, the impacting of the steady state governing rate on the instantaneous governing rate, the linear reducing or adding were taken to eliminate impact. And the relevant control functions were simulated. The performance optimization research improves the starting performance, improves the speed governing of the full condition, conserves the energy and improves the emissions.The monitoring interface was established by the controlDesk software which has function perfectly and operation friendly. The monitoring interface can achieved the interfacing between the model and user during the offline/online simulation, the data exchanging between virtual instrumentation and procedures, the tracking of the real-time curves, the adjusting of the parameters online and the recording data.4. Based on the dSPACE real-time simulation system, the semi-physical simulation platform was developed. The semi-physical simulation platform composes the real-time diesel simulation model, the real-time simulation monitoring interface, the functional I/O board, the real diesel electronic control system and the real actuator. The platform tested the starting, the stopping, the speed governing, the protection of the exceeding speed, the sequential turbocharger, the cylinder cutout and status monitoring. The results of the semi-physical simulation were compared to the test results of the matching machine. The results show that the simulation platform has the high precision and the real-time well. The simulation platform can accelerate the development of the marine diesel electronic control system and can reduce the cost of the testing. It can test the other diesel controller (such as diesel electronic speed governor) if the semi-physical simulation platform is expanded some functions, the simulation platform can test the marine power device in the laboratory. The simulation platform is universal. This overcomes the disadvantage of the matching machine test.5. For the characteristics of the mutual influence, mutual restraint and mutual coupling between various systems of the diesel, the intelligent speed control of the diesel was researched. Appling semi-physical simulation platform, the fuzzy control and artificial neural network control theory were researched to regulate the speed of the marine diesel. The fuzzy-PID controller and BP neural controller were designed to meet the marine diesel engine speed control requirements of the whole condition.The control theories were verified by using multi-parameter diesel simulation model. The simulation results were compared to the traditional PID speed controller. The results show that the fuzzy-PID speed controller and BP neural network speed controller are better than the traditional PID speed controller. This lays the solid foundation for developing the marine diesel speed intelligent control. The semi-physical simulation of the diesel electronic control system can replace the matching machine test, shorten the development cycle and decrease the development cost. At the same time, the rapid control prototyping was researched. This is the foundation of developing control system from the function design to the product conversion.