ECU-electronic control unit-electronic control unit. Different manufacturers have different names for the same parts. For example, Denso Company in Japan is called ECU, Doctor Company in Germany is called EDU, and Fu Wei Company is also called EDU, which is also called engine control unit-engine control unit. The basic function of ECU is to always control the engine in the best combustion state under real-time and external working conditions. ECU is widely used in various electronic control systems, such as electronic common rail system, ECS system, electronic governor, electronic distribution pump, electronic pump nozzle and so on. According to the pre-designed program, ECU calculates the information sent by various sensors, limits the parameters to the allowable voltage level after processing, and then sends them to relevant actuators to perform various predetermined control functions. The microprocessor calculates the fuel injection time, fuel injection quantity, fuel injection rate and fuel injection timing based on the input data and the data stored in the map. And these parameters are converted into time-varying electric quantity matching with engine operation. Because the work of the engine changes at a high speed, it requires high calculation accuracy and fast processing speed. The performance of ECU should develop with the development of engine technology, and the memory of microprocessor is getting bigger and bigger, and the information processing ability is getting stronger and stronger. Based on the engine speed and load, after calculation and processing by ECU, the action instruction is sent to the fuel injector, fuel supply pump, etc. , so that each cylinder has the most suitable fuel injection quantity, fuel injection rate and fuel injection timing to ensure the best combustion of each cylinder. Controlling fuel supply and fuel injection is the most basic function of vehicle ECU. Current cruise control, exhaust braking control, preheating control, fuel heating control, exhaust aftertreatment equipment control, EGR and boost pressure control, etc. , and data exchange and control with dashboard, AT and EBS through bus technology (such as CAN) are very powerful. We look forward to the improvement of China's level in this respect and truly realize the mastery of core technologies.