JPS5825547A - Method of controlling process of combustion of internal combustion engine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling the combustion process of an internal combustion engine, for example an Otto engine.

For example, in the characteristics of combustion chamber pressure, the first
In the case of the combustion process of the internal combustion engine illustrated in the figure, q phases can be distinguished. During the initial phase of combustion, about 400 DEG to 20 DEG before top dead center OT, a turbulent flame spark forms in the vicinity of the spark plug. In order for this phase, called ignition delay, to be able to pass into the second or main phase, the flame spark must reach the size of the turbulent flame field. In the main phase, the turbulent flame spreads into the combustion chamber so that the main mixture burns. After top dead center OT, the final phase of combustion from about 100 degrees to the trailing stage of the mixture, after the flame front. The time and development of each phase depend on various ignition conditions,
It depends on the mixture composition, intensity of turbulence, pressure, temperature and chemical properties of the fuel.

This three-phase mixture combustion is repeated every operating cycle. The successive combustion characteristics, each detectable by a pressure-crank angle diagram, fluctuate strongly if the operating conditions do not change. Unevenness in the operating periods reduces the commanded effective mean pressure and thus reduces the efficiency of the internal combustion engine, for example when operating in the over-air range. Furthermore, this discrepancy is due to the lack of high octane requirements for internal combustion engines throughout the United States. This is because this high octane requirement is determined by the operating cycle of the pressure at which mixture misfire occurs earliest. Furthermore, exhaust gas component No. regulated by law,
The release of HC and Co increases with cyclic fluctuations.

Based on this physical phenomenon, the object of the invention is to eliminate periodic fluctuations in the combustion process, thereby increasing the overall efficiency of the internal combustion engine and reducing the harmful exhaust gas emissions.

According to the present invention, this problem is solved by detecting the optimum value of the combustion characteristic quantity of the combustion chamber pressure as a function of all crank angles and storing it in the electronic control unit, and continuously measuring the actual combustion characteristic quantity of the combustion chamber. This problem can be solved by comparing the actual value with the target value of the electronic control device and compensating for the deviation between the actual value and the target value by controlling the mixture forming device and/or ignition device of the internal combustion engine. With the control method according to the invention, first the actual value of the continuous combustion process is taken for comparison and then equalized to the experimentally determined and stored optimum value. Advantageously, the adjustment quantity is stored electronically and the combustion chamber pressure is adjusted by changing the ignition point, so that the fuel-air mixture composition depends on the crank angle. used. The optimum target value curve is detected for each operating point in the characteristic range from no-load operation to maximum output and is stored in the electronic control unit.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The respective combustion chamber pressure of the engine 1 is detected continuously by a detection device 2 and is fed as an actual value signal to an electronic control device 3 which contains an optimal characteristic curve of the combustion chamber pressure as setpoint value. If there is a deviation between the actual value and the setpoint value, a control command is sent to the mixture forming device and/or the ignition device 5 of the engine 1 and the engine 1 is adjusted accordingly and accordingly The combustion chamber pressure is controlled to the desired value in each case.

In this way, in the case of an Otto engine, a total increase of about 6 qb of specific performance or efficiency can be achieved, so that the effective efficiency is improved. No. 304 to 5 in the excess air amount region
It is possible to reduce the zero coefficient. This advantage far outweighs the extra cost for the regulator and allows the entire Otto engine to be operated very economically.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the crank angle-combustion chamber pressure characteristics of an internal combustion engine for explaining the present invention. Fig. 2 is a block circuit electronic control device of a device implementing the method of the present invention. Gas forming device, 5...Ignition device Fig, 2

Claims (1)

[Claims] In a method for controlling the combustion process of an internal combustion engine, the optimum value of the combustion characteristic quantity of combustion chamber pressure is detected as a function of crank angle, stored in an electronic control device, and continuously measured on the actual combustion characteristic quantity of the combustion chamber. The actual value is compared with the target value of the electronic control device, and the deviation between the actual value and the target value is compensated for by controlling the mixture forming device and/or ignition device of the internal combustion engine. A method for controlling the combustion process of an internal combustion engine.