CN-122014440-A - Control method for pre-ignition inhibition and in-cylinder direct-injection hydrogen fuel nozzle

Abstract

The invention discloses a control method for suppressing pre-combustion, relates to power machinery, and solves the technical problem that the pre-combustion occurs due to the fact that the control protection cannot be carried out as the temperature of the injection part of the nozzle head cannot be monitored by the existing ECU. The method comprises the steps of installing a temperature sensor and a cooling water valve at an injection position of a nozzle head, setting a sampling period and a temperature threshold value, obtaining temperature peak values of the nozzle head in a plurality of sampling periods, judging a pre-ignition state of an engine according to the temperature peak values and the temperature threshold value, triggering a first pre-ignition suppression strategy when the pre-ignition state is judged to be a moderate continuous pre-ignition state, and triggering a second pre-ignition suppression strategy when the pre-ignition state is judged to be a severe continuous pre-ignition state. The invention also discloses a direct-injection hydrogen fuel nozzle in the cylinder. The invention ensures high-power and high-reliability operation of the hydrogen internal combustion engine.

Inventors

• ZHANG SONG
• WANG HUI
• NING DEZHONG
• MA JUNJIE
• QIN YUFENG
• CHEN HUAN
• Meng Jincui
• TAN ZONGHUI
• ZHOU ZHIYU

Assignees

• 广西玉柴机器股份有限公司

Dates

Publication Date

20260512

Application Date

20260331

Claims (7)

1. 1. A control method for suppressing the pre-combustion is characterized by comprising the steps of installing a temperature sensor (1) and a cooling water valve (5) at an injection position of a nozzle (4) head, setting a sampling period and a temperature threshold value, acquiring temperature peaks of the nozzle head in a plurality of sampling periods, judging the pre-combustion state of an engine according to the temperature peaks and the temperature threshold value, triggering a first pre-combustion suppression strategy when the pre-combustion state is judged to be a moderate continuous pre-combustion state, and triggering a second pre-combustion suppression strategy when the pre-combustion state is judged to be a severe continuous pre-combustion state.
2. 2. The method of claim 1, wherein the method of determining the pre-ignition state of the engine based on the temperature peak value and the temperature threshold value is to set a pre-ignition count value having an initial value of zero, and when the temperature peak value is greater than or equal to the temperature threshold value, it is determined that a pre-ignition phenomenon occurs and the pre-ignition count value is self-incremented; Obtaining the instantaneous temperature change rate of the current sampling period and the last sampling period according to the temperature peak value, comparing the instantaneous temperature change rate with a preset instantaneous temperature change rate threshold value, and executing a preliminary pre-ignition suppression strategy when the instantaneous temperature change rate is larger than the instantaneous temperature change rate threshold value; Acquiring an execution temperature peak value of a nozzle head in a sampling period after the preliminary pre-ignition suppression strategy is executed, judging that the pre-ignition state is accidental pre-ignition when the execution temperature peak value is smaller than a temperature threshold value, and resetting the pre-ignition count value; when the pre-ignition count value is greater than or equal to a preset first count value, the execution temperature peak value is greater than or equal to a temperature threshold value, and the instantaneous temperature change rate is smaller than the instantaneous temperature change rate threshold value, judging that the pre-ignition state is a medium continuous pre-ignition state; And when the pre-ignition count value is greater than or equal to a preset second count value, the execution temperature peak value is greater than or equal to a temperature threshold value, and the instantaneous temperature change rate is smaller than the instantaneous temperature change rate threshold value, judging that the pre-ignition state is a severe continuous pre-ignition state.
3. 3. The method of claim 2, wherein the preliminary pre-ignition suppression strategy is, Calibrating an ignition time delay value and an injection time delay value according to the temperature peak value, delaying a preset initial ignition time according to the ignition time delay value, and delaying the preset initial injection time according to the injection time delay value.
4. 4. The pre-ignition suppression control method according to claim 1, characterized in that the first pre-ignition suppression strategy is to open the cooling water valve (5) to cool down the head-injected cooling liquid of the nozzle (4).
5. 5. The pre-ignition suppression control method according to claim 1, characterized in that the second pre-ignition suppression strategy is to open the cooling water valve (5), cut off the injection of the nozzle (4), and stop the engine.
6. 6. An in-cylinder direct-injection hydrogen fuel nozzle that implements the pre-ignition suppression control method according to any one of claims 1 to 5, characterized in that the in-cylinder direct-injection hydrogen fuel nozzle includes, A temperature sensor (1) which is installed at the injection part of the nozzle (4) head and is used for acquiring the temperature of the nozzle head and outputting a temperature signal to the ECU (2); and the cooling water valve (5) is arranged at the injection part of the head part of the nozzle (4) and is connected with an engine cooling liquid pipeline through a pipeline, and is used for cooling the injection part of the head part of the nozzle (4) by injecting cooling liquid.
7. 7. The direct in-cylinder hydrogen injection fuel nozzle according to claim 6, wherein the cooling water valve (5) is connected to an engine coolant pipe through a pipe, the temperature sensor (1) is electrically connected to the ECU (2), and the ECU (2) is electrically connected to a controller of the cooling water valve (5).

Description

Control method for pre-ignition inhibition and in-cylinder direct-injection hydrogen fuel nozzle Technical Field The present invention relates to a power machine, and more particularly, to a method of controlling pre-ignition suppression and an in-cylinder direct-injection hydrogen fuel nozzle. Background The hydrogen internal combustion engine has the characteristics of high flame propagation speed and low ignition energy, and is extremely easy to generate abnormal combustion problems such as pre-combustion, knocking and the like under the working conditions of high load and high supercharging, and the pre-combustion phenomenon can cause serious problems such as sudden rise of in-cylinder pressure, overheat burning of a nozzle, damage to an engine structure and the like. The conventional in-cylinder direct injection hydrogen fuel nozzle cannot monitor the temperature of the injection part of the nozzle head in real time, and the ECU cannot recognize that the nozzle is overheated and the pre-combustion occurs, so that the control protection cannot be carried out in real time, and once the pre-combustion occurs, the nozzle and the engine are easily damaged, so that the high-power and high-reliability operation of the hydrogen internal combustion engine is severely restricted. Disclosure of Invention The invention aims to solve the technical problems that the prior art is insufficient, a control method for suppressing pre-combustion and a direct-injection hydrogen fuel nozzle in a cylinder are provided, and the technical problems that the pre-combustion occurs due to the fact that the control protection cannot be carried out as the temperature of the injection part of the nozzle head cannot be monitored by the existing ECU are solved. The method comprises the steps of installing a temperature sensor and a cooling water valve at an injection position of a nozzle head, setting a sampling period and a temperature threshold, acquiring temperature peaks of the nozzle head in a plurality of sampling periods, judging a pre-ignition state of an engine according to the temperature peaks and the temperature threshold, triggering a first pre-ignition suppression strategy when the pre-ignition state is judged to be a moderate continuous pre-ignition state, and triggering a second pre-ignition suppression strategy when the pre-ignition state is judged to be a severe continuous pre-ignition state. The method for judging the pre-combustion state of the engine according to the temperature peak value and the temperature threshold value is characterized in that a pre-combustion count value with an initial value of zero is set, and when the temperature peak value is greater than or equal to the temperature threshold value, the pre-combustion phenomenon is judged to occur and the pre-combustion count value is increased by one; Obtaining the instantaneous temperature change rate of the current sampling period and the last sampling period according to the temperature peak value, comparing the instantaneous temperature change rate with a preset instantaneous temperature change rate threshold value, and executing a preliminary pre-ignition suppression strategy when the instantaneous temperature change rate is larger than the instantaneous temperature change rate threshold value; Acquiring an execution temperature peak value of a nozzle head in a sampling period after the preliminary pre-ignition suppression strategy is executed, judging that the pre-ignition state is accidental pre-ignition when the execution temperature peak value is smaller than a temperature threshold value, and resetting the pre-ignition count value; when the pre-ignition count value is greater than or equal to a preset first count value, the execution temperature peak value is greater than or equal to a temperature threshold value, and the instantaneous temperature change rate is smaller than the instantaneous temperature change rate threshold value, judging that the pre-ignition state is a medium continuous pre-ignition state; And when the pre-ignition count value is greater than or equal to a preset second count value, the execution temperature peak value is greater than or equal to a temperature threshold value, and the instantaneous temperature change rate is smaller than the instantaneous temperature change rate threshold value, judging that the pre-ignition state is a severe continuous pre-ignition state. Further, the preliminary pre-ignition suppression strategy is that, Calibrating an ignition time delay value and an injection time delay value according to the temperature peak value, delaying a preset initial ignition time according to the ignition time delay value, and delaying the preset initial injection time according to the injection time delay value. Further, the first early-combustion inhibition strategy is to open the cooling water valve to cool down the cooling liquid sprayed by the head of the nozzle. Further, the second pre-ignition suppressi