CN104033310B - A kind of method being adjusted coke-oven gas engine ignition advance angle by composition detection - Google Patents

Abstract

The invention discloses a method for adjusting the ignition advance angle of a coke oven gas engine through component detection. When the composition of the coke oven gas changes, the volume fraction of hydrogen, methane, and carbon monoxide in the gas is determined based on the methane sensor and the carbon monoxide sensor. When the volume fraction of hydrogen, methane, and carbon monoxide meets certain conditions, the ignition is adjusted through the incremental PID controller Advance the angle, and update the volume fraction of hydrogen, methane and carbon monoxide in the charged erasable programmable read-only memory through the self-learning module. The invention uses the difference between the fuel composition measured by the sensor and the initial value stored in the control unit as input, and through the joint action of three incremental PID controllers, the ignition advance angle of the coke oven gas engine is corrected.

Description

A Method for Adjusting the Ignition Advance Angle of a Coke Oven Gas Engine Based on Composition Detection

technical field

The invention belongs to the technical field of engine engineering, and relates to a method for adjusting the ignition advance angle of a coke oven gas engine through component detection. It is suitable for coke oven gas engines modified from gasoline engines at present, and can realize fast and accurate self-adaptive control of ignition advance angle of coke oven gas engines when the components of coke oven gas change.

Background technique

With the rapid development of the automobile industry, its huge energy consumption has threatened the country's energy supply security, and at the same time, a large amount of exhaust gas has also directly threatened the ecological environment and human health. Alternative fuels for clean vehicles have become an important research topic in various countries. Alcohol fuel and gaseous fuel are the most widely used alternative fuels. Huge advantages, it is the preferred alternative fuel for cars at present. Combined with my country's national conditions, coke oven gas is an ideal clean alternative fuel.

At present, the coke oven gas engine is directly transformed on the basis of the gasoline engine, and the control strategy of the gasoline engine is retained. However, the composition of coke oven gas after coking gas passes through the purification device is complex and changeable (gasoline composition is considered to be fixed), 55-60% hydrogen, 23-28% methane and 5-8% carbon monoxide combustible components, 3- 5% nitrogen, 1-3% carbon dioxide and 3-4% non-combustible components of other gases. It is generally believed that the volume fraction of combustible components of coke oven gas is 90%. This characteristic of coke oven gas determines that the coke oven gas engine is Some control aspects are adjusted, especially for the control of ignition advance angle, which directly affects engine output power, fuel consumption, vehicle driving performance and harmful emissions generated by combustion. For gasoline engines, the ignition advance angle is composed of the basic ignition advance angle and the corrected ignition advance angle: the corrected ignition advance angle includes warm-up correction, idle speed stability correction, air-fuel ratio feedback correction, overheat correction, deflagration correction, etc.; while for coke oven Gas engine, on the basis of gasoline engine ignition control strategy, it is necessary to increase the ignition advance angle correction caused by the change of coke oven gas gas composition.

Contents of the invention

The object of the present invention is to propose a method for adjusting the ignition advance angle of a coke oven gas engine by detecting coke oven gas components. When the composition of coke oven gas changes, the volume fraction of hydrogen, methane, and carbon monoxide in the gas is determined based on the methane sensor and carbon monoxide sensor. When the volume fraction of hydrogen, methane, and carbon monoxide meets certain conditions, the ignition is adjusted through the incremental PID controller Advance the angle, and update the volume fraction of hydrogen, methane and carbon monoxide in the charged erasable programmable read-only memory (EEPROM) through the self-learning module.

Technical scheme of the present invention: the present invention is the method for adjusting the ignition advance angle of coke oven gas engine by coke oven gas composition detection, and its steps are:

Step 1: The methane sensor detects the methane composition in the gas and determines the methane volume fraction in the gas

Step 2: The carbon monoxide sensor detects the carbon monoxide component in the gas and determines the carbon monoxide volume fraction

Step 3: Obtain the real-time methane volume fraction in the gas carbon monoxide volume fraction and hydrogen gas fraction Compare the initial values of the three components in the charged erasable programmable read-only memory, and then get the error value and

Step 4: Put and They are respectively used as input parameters of the incremental PID controller to calculate the ignition advance angle correction value Δθ _ig .

Step Five: Update and Write to the Chargeable Erasable Programmable Read-Only Memory.

The beneficial effects of the present invention are:

(1) The present invention has the advantages of measuring methane volume fraction, carbon monoxide volume fraction and hydrogen gas integral number in the gas according to the methane sensor and the carbon monoxide sensor. The incremental PID controller corrects the ignition advance angle of the coke oven gas engine to increase the speed of engine adaptive control when the gas composition changes.

(2) The present invention uses the difference between the fuel composition measured by the sensor and the initial value stored in the control unit as input, and through the joint action of three incremental PID controllers, to correct the ignition advance angle of the coke oven gas engine. Incremental PID control has high control precision, and will not cause large fluctuations to the ignition advance angle, ensuring smooth operation of the engine. At the same time, incremental PID control has high robustness, and using incremental PID control as a correction method can improve the robustness of the engine system.

(3) The present invention also has a self-learning module. When there is a certain error between the gas composition and the initial value stored in the control unit, the initial value of the gas composition in the charged erasable programmable read-only memory can be automatically updated to improve the control speed and ensure the operation of the coke oven gas engine. item performance.

Description of drawings

Fig. 1 is a control block diagram of a coke oven gas engine adopting the present invention.

Fig. 2 is a structural schematic diagram of the ignition advance angle correction algorithm module of the coke oven gas engine gas composition based on the methane sensor and the carbon monoxide sensor.

Fig. 3 is the main flow chart of the ignition advance angle correction algorithm of the gas composition of the coke oven gas engine based on the methane sensor and the carbon monoxide sensor.

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing.

Fig. 1 is a control block diagram of a coke oven gas engine adopting the present invention.

The coke oven gas engine is improved on the basis of the gasoline engine, and the gas supply track is added. The main components include gas cylinders, pressure valves and sensors. In terms of ignition advance angle control of coke oven gas engines, on the basis of maintaining the original control strategy of gasoline engines, that is, by collecting various signals to determine the engine operating conditions to determine the basic ignition advance angle and warm-up correction, idle speed stability correction, Various ignition advance angle correction values such as air-fuel ratio feedback correction, overheat correction, knock correction, etc., and the ignition advance angle correction value affected by the gas composition is added.

This control block diagram adds the ignition advance angle correction algorithm module of the coke oven gas engine based on the methane sensor and carbon monoxide sensor, which is affected by the gas composition, on the basis of the original control strategy, so as to improve the combustion indicators of the coke oven gas engine in the cylinder , to ensure the performance of the engine operation.

Fig. 2 is a structural schematic diagram of the ignition advance angle correction algorithm module of the coke oven gas engine gas composition based on the methane sensor and the carbon monoxide sensor.

The determination of the gas composition of the coke oven gas engine mainly refers to the determination of its combustible components, namely methane, carbon monoxide and hydrogen. Since these three combustible components are bound to change within a certain range, three incremental PID controllers The amount of methane, carbon monoxide and hydrogen is corrected separately, and finally reflected in the control of the ignition advance angle of the coke oven gas engine.

Fig. 3 is the main flow chart of the ignition advance angle correction algorithm of the gas composition of the coke oven gas engine based on the methane sensor and the carbon monoxide sensor.

The concrete steps of this method are:

Step 1: The methane sensor detects the methane composition in the gas and determines the methane volume fraction in the gas

Step 2: The carbon monoxide sensor detects the carbon monoxide component in the gas and determines the carbon monoxide volume fraction

Step 3: Obtain the real-time methane volume fraction in the gas carbon monoxide volume fraction and hydrogen gas fraction Compare the initial values of the three components in the charged erasable programmable read-only memory, and then get the error value and

Step 4: Put and As the input parameters of the incremental PID controller, calculate the ignition advance angle correction value Δθ _ig :

${\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; \&lsqb;</span>{\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}}_{{\mathrm{<span\; class="notranslate">\; CH</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; C</span>}\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}}_{{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; \&rsqb;</span>$

in, $a_1=K_P\left(1+\frac{T}{T_I}+\frac{T_{\mathrm{D.}}}{T}\right),a_2=-\frac{K_P}{(1+\frac{2T_{\mathrm{D.}}}{T})},a_3=K_P\frac{T_{\mathrm{D.}}}{T},$ [ ] indicates rounding, superscript indicates different consecutive sampling values, K _p indicates proportional coefficient; T _I indicates integration time, unit is second; T _D indicates differential time, unit is second; T indicates sampling period, unit is second.

Step Five: Update and Write to the Chargeable Erasable Programmable Read-Only Memory.

Claims (1)

1. A method for adjusting the ignition advance angle of coke oven gas engine by composition detection, is characterized in that comprising the following steps: Step 1: The methane sensor detects the methane composition in the gas and determines the methane volume fraction in the gas Step 2: The carbon monoxide sensor detects the carbon monoxide component in the gas and determines the carbon monoxide volume fraction Step 3: Obtain the real-time methane volume fraction in the gas carbon monoxide volume fraction and hydrogen gas fraction Compare the initial values of the three components in the charged erasable programmable read-only memory, and then get the error value and Step 4: Put and As the input parameters of the incremental PID controller, calculate the ignition advance angle correction value Δθ _ig : ${\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; g</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; \&lsqb;</span>{\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}}_{{\mathrm{<span\; class="notranslate">\; CH</span>}}_{\mathrm{<span\; class="notranslate">\; 4</span>}}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; C</span>}\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; \&Delta;\&theta;</span>}}_{{\mathrm{<span\; class="notranslate">\; h</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; \&rsqb;</span>$ in ${\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; P</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; T</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; I</span>}}}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}}{\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; P</span>}}}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}}{\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; )</span>}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; P</span>}}\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}}{\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; ;</span>$ [ ] indicates rounding, the superscripts 1, 2, and 3 respectively indicate three consecutive sampling values, K _p indicates the proportional coefficient; T _I indicates the integration time, the unit is second; T _D indicates the differential time, the unit is second; T indicates the sampling period , the unit is second; Step Five: Update and Write to the Chargeable Erasable Programmable Read-Only Memory.