阅读说明：本技术 一种基于跳缸技术的天然气发动机工作方法 (Natural gas engine working method based on cylinder jumping technology ) 是由 杨立平 王佳琦 宋恩哲 王立媛 姚崇 于 2020-02-18 设计创作，主要内容包括：本发明的目的在于提供一种基于跳缸技术的天然气发动机工作方法,传感器通过采集当前工况下发动机负荷、转速信号,再由发动机电控单元ECU对当前工况进行判断是否符合进入跳缸的条件,如果当前工况需要进行跳缸调整,则需要根据传感器所采集的信号对所需的停缸数进行选择,然后对需要其停止工作的气缸进行切断燃气喷射以及停止点火的处理,使每一气缸都在发动机低负荷停缸的工作循环中参与停缸过程,以实现跳缸过程。本发明通过根据最优停缸数对停缸顺序进行设计既可以达到传统停缸技术所要求的将发动机工作保持在经济能耗区,也可以降低发动机在长时间处于停缸状态中,由于停止特定气缸工作所导致的曲轴受力不均匀所引起的曲轴强度问题。(The invention aims to provide a natural gas engine working method based on a cylinder tripping technology.A sensor collects signals of engine load and rotating speed under the current working condition, an engine Electronic Control Unit (ECU) judges whether the current working condition meets the condition of entering the cylinder tripping, if the current working condition needs to be adjusted, the required cylinder stopping number needs to be selected according to the signals collected by the sensor, and then the treatment of cutting off gas injection and stopping ignition is carried out on the cylinder needing to stop working, so that each cylinder participates in the cylinder stopping process in the working cycle of low-load cylinder stopping of the engine, and the cylinder tripping process is realized. The invention can keep the engine working in an economic energy consumption area required by the traditional cylinder deactivation technology by designing the cylinder deactivation sequence according to the optimal cylinder deactivation number, and can also reduce the strength problem of the crankshaft caused by uneven stress of the crankshaft due to the fact that the engine is in a cylinder deactivation state for a long time and the specific cylinder is stopped.)

1. A natural gas engine working method based on a cylinder tripping technology is characterized by comprising the following steps: the sensor collects the load and rotation speed signals of the engine under the current working condition, then the ECU of the engine judges whether the current working condition meets the condition of entering the cylinder jump, if the current working condition needs to be adjusted by the cylinder jump, the required cylinder deactivation number needs to be selected according to the signals collected by the sensor, then the cylinder needing to stop working is subjected to the treatment of cutting off gas injection and stopping ignition, so that each cylinder participates in the cylinder deactivation process in the working cycle of low-load cylinder deactivation of the engine, and the cylinder jump process is realized.

2. The natural gas engine working method based on the cylinder tripping technology as claimed in claim 1, characterized in that: when the natural gas engine is a six-cylinder natural gas engine, the engine runs under low load, the ECU judges the current working condition that the engine needs to enter a cylinder jumping state to reduce energy consumption, all cylinders of the engine are alternately switched to perform cylinder deactivation operation according to the ignition sequence of the six-cylinder natural gas engine, the cylinder deactivation times of all cylinders are ensured to be consistent in the whole cylinder jumping working process, so that the cylinder jumping working process of the engine is realized, and the corresponding relation between the cylinder deactivation process and the crank angle is shown in the following table:

Technical Field

The invention relates to a natural gas engine, in particular to a control method of the natural gas engine.

Background

The unregulated exploitation of global petroleum resources is increasing the threat of resource environment and energy exhaustion faced by human beings. The method finds and develops new energy, improves the use efficiency of the existing energy, and has great significance for establishing a sustainable energy system, promoting the development of social economy and the improvement of ecological environment and reducing the dependence on fossil energy. Among the energy saving methods applied to engines, cylinder deactivation technology is once more emphasized as a method for reducing the energy consumption of engines with the gradual improvement of electronic control systems of engines.

The cylinder deactivation technology is also called as variable displacement technology or cylinder deactivation technology, and means that when an engine runs under partial load, fuel supply, ignition and air intake and exhaust of partial cylinders are cut off through related mechanisms, the work is stopped, and the load factor of the residual working cylinders is increased, so that the efficiency is improved, and the fuel consumption is reduced.

At present, the working principle of most cylinder deactivation technologies is that signals such as engine rotating speed load and the like are collected through a sensor, an Electronic Control Unit (ECU) judges whether cylinder deactivation is needed or not according to the obtained signals under the current working condition, when cylinder deactivation operation is needed, the electronic control unit judges the optimal number of cylinders to be deactivated, and fuel supply and ignition of corresponding cylinders are cut off at the same time, so that the cylinder deactivation operation of an engine is realized. The patent with publication number CN107795395A discloses a method for reducing torque of an engine in a cylinder-cut manner, which finally realizes that the torque reduction precision of the engine is improved by more than one time by adding functions of torque reduction efficiency calculation, torque reduction coordination, a cylinder-cut strategy, cylinder-cut execution, ignition correction and the like into a control strategy. However, the invention does not consider the potential safety hazard of the engine operation caused by the strength problem of the crankshaft due to uneven stress caused by long-time stop of the specific cylinder in the cylinder-off operation process.

Disclosure of Invention

The invention aims to provide a natural gas engine working method based on a cylinder jumping technology, which solves the problem that strength is generated due to uneven stress of a crankshaft because a specific cylinder stops working for a long time in a cylinder deactivation working process.

The purpose of the invention is realized as follows:

The invention relates to a natural gas engine working method based on a cylinder tripping technology, which is characterized by comprising the following steps of: the sensor collects the load and rotation speed signals of the engine under the current working condition, the ECU of the engine judges the current working condition whether the current working condition meets the condition of entering the cylinder jump, if the current working condition needs to be adjusted by the cylinder jump, the required cylinder stopping number needs to be selected according to the signals collected by the sensor, and then the cylinder needing to stop working is subjected to the treatment of cutting off gas injection and stopping ignition, so that each cylinder participates in the cylinder stopping process in the working cycle of low-load cylinder stopping of the engine, and the cylinder jump process is realized.

The present invention may further comprise:

1. When the natural gas engine is a six-cylinder natural gas engine, the engine runs under low load, the ECU judges the current working condition that the engine needs to enter a cylinder jumping state to reduce energy consumption, all cylinders of the engine are alternately switched to perform cylinder deactivation operation according to the ignition sequence of the six-cylinder natural gas engine, the cylinder deactivation times of all cylinders are ensured to be consistent in the whole cylinder jumping working process, so that the cylinder jumping working process of the engine is realized, and the corresponding relation between the cylinder deactivation process and the crank angle is shown in the following table:

The invention has the advantages that: the invention can keep the engine working in an economic energy consumption area required by the traditional cylinder deactivation technology by designing the cylinder deactivation sequence according to the optimal cylinder deactivation number, and can also reduce the problem of crankshaft strength caused by uneven stress of the crankshaft due to the fact that the engine stops working in a specific cylinder in a cylinder deactivation state for a long time.

Detailed Description

The invention is described in more detail below by way of example:

The invention relates to a natural gas engine working method based on a cylinder jumping technology, which is suitable for natural gas engines with four or more cylinders. The sensor collects signals of engine load, rotating speed and the like under the current working condition, and an engine Electronic Control Unit (ECU) judges whether the current working condition meets the condition of entering the cylinder jump or not. If the current working condition needs to carry out cylinder jumping adjustment, the required cylinder stopping number needs to be selected according to signals collected by the sensor, the cylinder stopping sequence is designed according to the optimal cylinder stopping number, and then the treatment of cutting off gas injection and stopping ignition is carried out on the cylinders needing to stop working, so that each cylinder can participate in the cylinder stopping process in the working cycle of low-load cylinder stopping of the engine, and the cylinder jumping process is realized. Taking a six-cylinder natural gas engine as an example, when the engine runs under low load, the ECU judges the current working condition that the engine needs to enter a cylinder-jumping state to reduce energy consumption, the optimal number of cylinder stops is calculated to be two cylinders, and the cylinder-stopping sequence is designed according to the ignition sequence of the six-cylinder natural gas engine, so that the cylinders of the engine are alternately subjected to cylinder-stopping operation, and the cylinder-stopping times of the cylinders are basically consistent in the whole cylinder-jumping working process, thereby realizing the cylinder-jumping working process of the engine.

The correspondence between the cylinder deactivation process and the crank angle is shown in the following table:

When the engine needs to jump the cylinder, the cylinder stopping sequence needs to be designed according to the required cylinder stopping number, and the main design requirement is that the influence caused by uneven stress of the crankshaft is reduced by designing different cylinder stopping sequences.

When the engine needs to carry out cylinder jumping operation, the cylinder stopping sequence is designed according to the ignition sequence of the engine, so that the cylinder stopping numbers at the left end and the right end of the crankshaft are not easy to differ too much, and the crankshaft is prevented from being buckled due to unbalanced stress.

The invention is further explained by combining a table with a cylinder jumping working process of a series six-cylinder natural gas engine, and the number of cylinder deactivation and the cylinder deactivation sequence in the cylinder jumping process are not limited in the example during specific working, and the specific conditions are determined according to the number of cylinders of the engine and specific working conditions.

When the engine works, signals such as load and rotating speed of the engine are collected through a sensor, the collected signals are processed by an ECU (electronic control Unit), the condition that the engine needs to enter a cylinder jumping state under the working condition is obtained, the engine works in an economic energy consumption area, the ECU judges that the optimal cylinder stopping number required under the working condition is two cylinders, the cylinder jumping sequence of the engine is designed according to the optimal cylinder stopping number and the ignition sequence of an inline six-cylinder engine, the cylinders are numbered from the cylinder close to the input end of a crankshaft, the serial numbers of the cylinders are respectively 1, 2, 3, 4, 5 and 6, three working cycles of the engine are designed into a cylinder jumping period according to the ignition sequence of the inline six-cylinder engine, and the cylinder jumping working process requires that the designed cylinder stopping sequence in the cylinder jumping period at least ensures that each cylinder is sequentially operated, therefore, six cylinders of the engine can be deactivated in groups, two cylinders can be stopped in each cycle in three cycles of a cylinder deactivation period, meanwhile, in order to ensure that the stress of the crankshaft is uniform and harmful phenomena such as vibration, noise and the like are not generated in the cylinder deactivation process, two cylinders stopped in each cycle are positioned at the symmetrical positions of the crankshaft, and the cylinder deactivation sequence is designed according to the requirements: cycle one 1-6, cycle two 2-5 and cycle three 3-4, corresponding to the ignition sequence of each cycle, 5-3-2-4, 1-3-6-4 and 1-5-6-2.