Description:Complete Specification

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of the invention
[0001] This invention relates to a method to identify backfire in a hydrogen engine, and more specifically to the method to identify backfire in the hydrogen engine with a standard engine management system.

Background of the invention
[0002] CN 116877305 A describes a spray pipe, a hydrogen supply system and an anti-backfire control method of a hydrogen engine. The spray pipe is applied to the hydrogen engine, the spray pipe comprises a spray pipe body, and the spray pipe body is provided with an inlet end used for receiving airflow and an outlet end used for spraying out the airflow. The outlet end is constructed to be of a Laval tubular structure, the Laval tubular structure comprises a gradually-shrinking section and a gradually-expanding section which are communicated. An air spraying opening of the spraying pipe is formed in the side, away from the gradually-shrinking section, of the gradually-expanding section. The Rafael tubular structure is configured to enable the flow velocity to be increased after air flow sequentially flows through the gradually-shrinking section and the gradually-expanding section. According to the spray pipe, the hydrogen supply system and the anti-backfire control method of the hydrogen engine, the backfire risk can be effectively reduced.

Brief description of the accompanying drawing
[0003] Figure 1 illustrates an algorithm to identify backfire in a hydrogen engine with a standard engine management system in one embodiment of the invention.

Detailed description of the embodiments
[0004] Figure 1 illustrates a method 100 to identify backfire in the hydrogen engine with a standard engine management system. The method 100 comprises determining 110 a pressure of hydrogen gas in an inlet manifold of the hydrogen engine by means of a pressure sensor, determining 120 a temperature of hydrogen gas in the inlet manifold of the hydrogen engine by means of a temperature sensor, and determining 130 if the pressure of hydrogen gas in the inlet manifold of the hydrogen engine is greater than a pre-determined threshold pressure of hydrogen gas. The method 100 further comprises determining 140 if the temperature of hydrogen gas in the inlet manifold of the hydrogen engine is greater than a pre-determined threshold temperature of hydrogen gas, and determining 150 that the hydrogen engine has backfired if the pressure of hydrogen gas in the inlet manifold of the hydrogen engine is greater than the pre-determined threshold pressure of hydrogen gas and if the temperature of hydrogen gas in the inlet manifold of the hydrogen engine is greater than the pre-determined threshold temperature of hydrogen gas.

[0005] Figure 1 illustrates a method 100 to identify backfire in the hydrogen engine with a standard engine management system. The method 100 comprises determining 110 a pressure of hydrogen gas in an inlet manifold of the hydrogen engine by means of a pressure sensor. More specifically, the pressure sensor that is deployed within the inlet manifold of the hydrogen engine determines the pressure of hydrogen gas in the inlet manifold of the hydrogen engine and transmits a signal that is representative of the pressure to an electronic control unit. The method 100 comprises determining 120 a temperature of hydrogen gas in the inlet manifold of the hydrogen engine by means of a temperature sensor. More specifically, the temperature sensor that is deployed within the inlet manifold of the hydrogen engine determines the temperature of hydrogen gas in the inlet manifold of the hydrogen engine and transmits a signal that is representative of the temperature to an electronic control unit. The electronic control unit determines 130 if the pressure of hydrogen gas in the inlet manifold of the hydrogen engine is greater than a pre-determined threshold pressure of hydrogen gas. Once the electronic control unit determines 130 if the pressure of hydrogen gas in the inlet manifold of the hydrogen engine is greater than a pre-determined threshold pressure of hydrogen gas, the electronic control unit determines 140 if the temperature of hydrogen gas in the inlet manifold of the hydrogen engine is greater than a pre-determined threshold temperature of hydrogen gas. The electronic control unit therein determines 150 that the hydrogen engine has backfired if the pressure of hydrogen gas in the inlet manifold of the hydrogen engine is greater than the pre-determined threshold pressure of hydrogen gas. In addition, if the temperature of hydrogen gas in the inlet manifold of the hydrogen engine is greater than the pre-determined threshold temperature of hydrogen gas in addition to determining that the pressure of hydrogen gas in the inlet manifold of the hydrogen engine is greater than the pre-determined threshold pressure of hydrogen gas, the electronic control unit confirms that the hydrogen engine has backfired.

[0006] The method 100 to identify backfire in the hydrogen engine with a standard engine management system further comprises determining 160 a knocking effect of hydrogen gas in the inlet manifold of the hydrogen engine by means of a knock sensor. The method 100 further comprises determining 170 that the hydrogen engine has backfired if the knock sensor records a knocking effect in the hydrogen engine in addition to determining that the pressure of hydrogen gas in the inlet manifold of the hydrogen engine is greater than the pre-determined threshold pressure of hydrogen gas and determining 140 that the temperature of hydrogen gas in the inlet manifold of the hydrogen engine is greater than the pre-determined threshold temperature of hydrogen gas. The measurement from the knock sensor can be used to corroborate that the hydrogen engine has backfired.

[0007] In an exemplary embodiment, the method 100 to identify backfire in the hydrogen engine with a standard engine management system further comprises measuring 180 a current flowing through a spark plug and corelating the current flowing through the spark plug with an increase in pressure in a combustion chamber during an intake stroke beyond a user defined threshold pressure. Under normal circumstances, during the suction stroke in the combustion chamber of the hydrogen engine, the pressure of the hydrogen gas decreases substantially. However, when the hydrogen engine has backfired the pressure of the hydrogen gas in the combustion chamber slightly increases. This slight increase in the pressure of the hydrogen gas in the combustion chamber is directly corelated to the increase in the voltage that flows through the spark plug. Therefore, the increase in the voltage that flows through the spark plug can be directly corelated to the backfire in the inlet manifold of the hydrogen engine during the suction stroke of the hydrogen engine. The slight increase in pressure of hydrogen in the combustion chamber during the intake stroke beyond the user defined threshold pressure is indicative of a backfire in the inlet manifold of the hydrogen engine.

[0008] The method 100 to identify backfire in the hydrogen engine with a standard engine management system further comprising implementing 190 a lambda sensor in the intake manifold of the hydrogen engine for measuring a rate of depletion of oxygen in the intake manifold of the hydrogen engine. In an exemplary embodiment, the rate of depletion of oxygen in the intake manifold of the hydrogen engine beyond a user defined threshold limit is indicative of a backfire in the inlet manifold of the hydrogen engine.

[0009] It must be understood that the embodiments explained above are only illustrative and do not limit the scope of the disclosure. Many modifications in the embodiments with regard to dimensions of various components are envisaged and form a part of this invention. The scope of the invention is only limited by the scope of the claims.
, Claims:We Claim

1. A method (100) to identify backfire in a hydrogen engine with a standard engine management system, the method comprising:
determining (110) a pressure of hydrogen gas in an inlet manifold of the hydrogen engine by means of a pressure sensor;
determining (120) a temperature of hydrogen gas in the inlet manifold of the hydrogen engine by means of a temperature sensor;
determining (130) if the pressure of hydrogen gas in the inlet manifold of the hydrogen engine is greater than a pre-determined threshold pressure of hydrogen gas;
determining (140) if the temperature of hydrogen gas in the inlet manifold of the hydrogen engine is greater than a pre-determined threshold temperature of hydrogen gas; and
determining (150) that the hydrogen engine has backfired if the pressure of hydrogen gas in the inlet manifold of the hydrogen engine is greater than the pre-determined threshold pressure of hydrogen gas and if the temperature of hydrogen gas in the inlet manifold of the hydrogen engine is greater than the pre-determined threshold temperature of hydrogen gas.

2. The method (100) to identify backfire in the hydrogen engine with a standard engine management system in accordance with Claim 1, further comprising determining (160) a knocking effect of hydrogen gas in the inlet manifold of the hydrogen engine by means of a knock sensor.

3. The method (100) to identify backfire in the hydrogen engine with a standard engine management system in accordance with Claim 2, further comprising determining (170) that the hydrogen engine has backfired if the knock sensor records a knocking effect in the hydrogen engine.

4. The method (100) to identify backfire in the hydrogen engine with a standard engine management system in accordance with Claim 1, further comprising measuring (180) a current flowing through a spark plug and corelating the current flowing through the spark plug with an increase in pressure in a combustion chamber during an intake stroke beyond a user defined threshold pressure.

5. The method (100) to identify backfire in the hydrogen engine with a standard engine management system in accordance with Claim 4, wherein the increase in pressure in the combustion chamber during the intake stroke beyond the user defined threshold pressure is indicative of a backfire in the inlet manifold of the hydrogen engine.

6. The method (100) to identify backfire in the hydrogen engine with a standard engine management system in accordance with Claim 1, further comprising implementing (190) a lambda sensor in the intake manifold of the hydrogen engine for measuring a rate of depletion of oxygen in the intake manifold of the hydrogen engine.

7. The method (100) to identify backfire in the hydrogen engine with a standard engine management system in accordance with Claim 6, wherein the rate of depletion of oxygen in the intake manifold of the hydrogen engine beyond a user defined threshold limit is indicative of a backfire in the inlet manifold of the hydrogen engine.