This project belongs to energy and environmental technology.
In response to the national requirements for energy conservation and emission reduction and the power, economy and drivability of commercial vehicles, this project carries out research and development of the core component of the electronic control system of natural gas engines, namely the controller. The project has completed hardware circuits, control strategies and software design, and the whole process of system integration, reliability and environmental testing, real machine and vehicle testing have overcome and broken through many key and core technologies. The project results have been appraised by the expert group, and the conclusion is that "the achievement level is leading in China. Performance has reached the international advanced level." After emission, engineering development and various verifications, my country's first independently designed gas engine controller suitable for CNG, LNG and LNG was finally successfully developed and put into batch production. The project has achieved the following main innovative results:
(1) For the first time, a closed-loop control strategy for gas injection and air-fuel ratio based on a wide-range oxygen sensor and a generalized predictive model was creatively developed, which improved the transient following accuracy of air-fuel ratio in natural gas engines; A wide-area oxygen sensor is used to detect changes in air-fuel ratio over a wide range of air-fuel ratio, and a generalized predictive control (GPC) algorithm is researched and developed. Air-fuel ratio control is obtained through an optimization control algorithm based on parameter models, rolling optimization and combined with feedback correction. Good dynamic characteristics and strong robustness.
(2) A comprehensive and complete air management system has been developed to realize supercharged and intermediate-cooled lean combustion, and a reduced-order full-state feedback controller has been designed to ensure that on the basis of fast response and small overshoot of intake manifold pressure, pressure stabilization time is greatly improved; Air charge control based on throttle flow model, electronic throttle closed-loop control and adaptation, boost pressure closed-loop control, and anti-surge valve control realize lean combustion process control, reaching the advanced level abroad.
(3) By establishing a mathematical model of high-energy ignition drive control, the calculation methods of the primary voltage and charging current of the ignition coil under various circumstances are studied. A control algorithm based on iterative learning correction of ignition energy and ignition advance angle achieves accurate control of ignition energy; A seamless switching program for ignition benchmarks is developed when the phase sensor fails to ensure rapid switching of ignition benchmarks when the phase signal fails, thereby ensuring normal operation of the engine.
(4) Taking into account the harsh operating environment and long-life reliability requirements of natural gas engines, an intelligent control strategy for all engine operating conditions has been developed and designed, including adaptive cylinder judgment and speed calculation, idle closed-loop control, and closed-loop control of the highest altitude vehicle speed., variable speed closed-loop control, etc., ensure rapid cylinder judgment and start of the engine, and safe and stable operation.
(5) Developed a super-performance controller hardware platform, and the internal integrated solenoid valve driving capability is currently one of the few strongest technical solutions in the world; up to 40 channels of high-speed signal sampling and more than 30 channels of driving outputs provide a strong guarantee for the realization of rich system functions; Support SCR aftertreatment and EGR+DOC aftertreatment technical routes, have complete fault monitoring, recording, failure protection, output and other strategies, and have OBD II, EOBD, and national IV, national V and national VI emission control capabilities.
(6) Based on the product concept and according to the needs of product supporting applications, we have independently developed various supporting tools, including: calibration tool software HEGC AL, diagnostic tool HEGST, vehicle off-line Detection Tools HEGEOL, etc., realizing the provision and support of a series of products throughout the process of controller research and development, production and application services.
The results of the project have been mass produced and have been used in many complete vehicle factories across the country, with good market response. Currently, more than 4000 complete vehicles are in operation. In 2012, the system added 10 million yuan in output value and 1.32 million yuan in tax revenue. With the country's strict control of PM2.5 and the increasingly prominent energy issues, it is estimated that the new output value will be 30 million yuan and the tax revenue will be 3 million yuan in 2013. The project applied for and authorized 6 patents and software copyrights, and published 22 papers.