A starting control strategy for a large-bore diesel engine

Abstract

The application discloses a starting control strategy of a large-bore diesel engine and relates to the field of engine control, and solves the technical problem that the existing pre-oil supply technology can cause slow pressure building of engine oil pressure and unsafe starting. The strategy comprises the following steps: performing a first pre-oil supply action on the engine; after the first pre-oil supply ends, starting a motor; when the engine speed reaches a starting success speed, performing a second pre-oil supply action and determining whether the engine enters an idle state; and after the engine speed enters the idle state, ending the starting. On the basis of the existing pre-oil supply configuration scheme, the application adds a second pre-oil supply action after a motor starting signal is exited, so that the situation of low engine oil pressure caused by further driving of engine oil circulation by the engine is avoided.

Description

Technical Field

[0001] This invention relates to the field of engine control, and more specifically, to a starting control strategy for a large-bore diesel engine. Background Technology

[0002] For large-bore diesel engines, performing pre-lubrication before starting ensures adequate lubrication of core moving parts such as the crankshaft and bearings, and the establishment of an oil film, thus guaranteeing safe starting and operation. For data centers and emergency backup power supplies, even higher requirements are placed on engine starting and operation, requiring the engine to have a 15-second load-bearing capacity. Therefore, higher demands are placed on the safe starting and operation of the engine. Currently, for engines not used in data centers or emergency backup power supplies, the control strategy involves performing pre-lubrication for a certain period, then issuing the engine start command, and finally accelerating after the idle speed has stabilized for a certain time.

[0003] Regardless of whether it is a generator for a data center or an emergency backup power source, the strategy of executing the engine start command after a certain period of pre-fueling can meet the starting and speed-up requirements of generator sets with different requirements. However, as the engine runs and further drives the oil circulation, there are hidden dangers such as low oil pressure during the engine start-up process, differences in the pressure-building capacity of different engines, and low oil pressure build-up at different oil temperatures. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a starting control strategy for a large-bore diesel engine to address the shortcomings of the prior art, thereby solving the technical problem that the existing pre-fuel technology will cause slow oil pressure build-up and unsafe starting.

[0005] The present invention discloses a starting control strategy for a large-bore diesel engine, wherein the strategy is as follows:

[0006] Perform the first pre-fuel injection action on the engine;

[0007] After the first pre-fuel injection is completed, the starter motor starts;

[0008] When the engine speed reaches the starting speed, the second pre-fuel injection action is performed, and at the same time it is determined whether the engine has entered the idling state.

[0009] The start-up process ends when the engine speed reaches idle.

[0010] As a further improvement, when the generator set instrument of the engine outputs a start signal, the ECU of the engine controls the pre-fuel pump to start according to the start signal to perform the first pre-fuel injection.

[0011] Furthermore, during the starter motor start-up process, if the start signal is withdrawn and the engine speed has not reached the start-up speed, the start-up ends.

[0012] Furthermore, when the engine speed reaches the starting speed, the starter motor's disengagement signal is used as the action signal for the pre-supply pump to perform the second pre-supply action.

[0013] Furthermore, once the engine enters idle mode, the second pre-fuel injection action is discontinued, and the pre-fuel injection pump operates in normal fuel injection mode.

[0014] Beneficial effects

[0015] The advantages of this invention are:

[0016] 1. Based on the existing pre-lubrication configuration, the present invention adds a secondary pre-lubrication action after the motor start signal is withdrawn, so as to avoid the situation of low oil pressure caused by the engine running further driving the oil circulation.

[0017] 2. In this invention, the starter motor and the pre-fuel pump do not work simultaneously, making it less likely to cause a momentary low battery voltage, thus ensuring the normal operation of the engine ECU. Attached Figure Description

[0018] Figure 1 This is a flowchart of the control strategy of the present invention. Detailed Implementation

[0019] The present invention will be further described below with reference to embodiments, but this does not constitute any limitation on the present invention. Any limited modifications made by any person within the scope of the claims of the present invention are still within the scope of the claims of the present invention.

[0020] See Figure 1 The present invention discloses a starting control strategy for a large-bore diesel engine, the strategy being as follows:

[0021] The engine performs the first pre-fuel injection action. After the engine's generator set instrument outputs a start signal, the engine's ECU controls the pre-fuel injection pump to start according to the start signal to perform the first pre-fuel injection.

[0022] After the first pre-fuel injection is completed, the starter motor will activate. If the start signal is withdrawn during the starter motor's activation process and the engine speed has not reached the starting speed, the start-up will end.

[0023] When the engine speed reaches the starting success speed, the second pre-fuel injection action is executed. Simultaneously, it checks whether the engine has entered idle. When the engine speed reaches the starting success speed, the starter motor's disengagement signal serves as the signal for the pre-fuel injection pump to execute the second pre-fuel injection action. During the second pre-fuel injection, the engine transitions from the starting success speed to idle, effectively mitigating the problem of excessive oil pressure drop caused by engine idle.

[0024] The starter motor and pre-fuel pump do not work simultaneously, making it less likely for the battery voltage to drop too low momentarily, thus ensuring the normal operation of the engine ECU.

[0025] Once the engine reaches idle speed, the start-up process ends. After the engine reaches idle speed, the second pre-lubrication action disengages, and the pre-lubrication pump operates in normal lubrication mode. The pre-lubrication pump's operation ensures adequate lubrication for the engine, protecting its safe starting operation.

[0026] Both the first and second pre-fuel injection times can be set via the ECU. For example, the first pre-fuel injection time can be set to 3 seconds, and the second pre-fuel injection time to 2 seconds. Setting two different pre-fuel injection times can meet the requirements for rapid starting while ensuring sufficient oil film establishment for engine starting, effectively eliminating the potential risk of insufficient starter oil pressure.

[0027] The oil pressure build-up capacity varies at different oil temperatures. At higher oil temperatures, the oil viscosity decreases and its fluidity increases, resulting in lower oil pressure build-up over the same period of time.

[0028] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention, and these will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. A starting control strategy for a large-bore diesel engine, characterized in that, The strategy is as follows: Perform the first pre-fuel injection action on the engine; After the first pre-fuel injection is completed, the starter motor starts; When the engine speed reaches the starting speed, the second pre-fuel injection action is performed, and at the same time it is determined whether the engine has entered the idling state. Once the engine speed reaches idle, the start-up process ends. When the engine speed reaches the starting speed, the starter motor's disengagement signal is used as the action signal for the pre-fuel pump to perform the second pre-fuel injection action.

2. The starting control strategy for a large-bore diesel engine according to claim 1, characterized in that, When the generator set instrument of the engine outputs a start signal, the engine ECU controls the pre-fuel pump to start according to the start signal to perform the first pre-fuel injection.

3. The starting control strategy for a large-bore diesel engine according to claim 2, characterized in that, If the start signal is withdrawn during the starter motor start-up process and the engine speed has not reached the start-up speed, the start-up process ends.

4. The starting control strategy for a large-bore diesel engine according to claim 1, characterized in that, Once the engine enters idle mode, the second pre-fuel injection action is discontinued, and the pre-fuel injection pump operates in normal fuel injection mode.

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