Multi-point gas electric control spraying system and method based on pressure-time control

Abstract

The invention discloses a multi-point gas electric control spraying system and a method based on pressure-time control. The system comprises a gas supply system, an air supply system and a control unit, wherein a throttle valve in the air supply system is controlled to supply air; the control unit determines a spraying lasting period, namely spraying lasting time according to detected gas information in the gas supply system and air information in the air supply system; meanwhile, the control unit also controls the openness of the gas control valve to control the pressure in a gas common rail pipe; and the control unit realizes premixing of gas and air through controlling a spraying valve in the gas supply system to spray the gas. The system improves mixing of the gas and the air under medium and low loads, prolongs the gas spraying lasting period under the medium and low loads through reducing the gas pressure, introduces the air and the gas into a cylinder while mixing at most time of the intake stroke, and accelerates excellent mixing of the gas and the air.

Description

technical field [0001] The invention relates to the field of gas supply for gas engines, in particular to a multi-point gas electronically controlled injection system and method based on pressure-time control. Background technique [0002] At present, the air intake systems of large-bore gas engines produced by large-bore gas engine manufacturers at home and abroad mostly adopt the technical route of premixing and multi-point injection, and foreign companies also mostly use these two technical routes. [0003] Premixing uses a mechanical mixer or a single-point injection valve to mix air and gaseous fuel outside the cylinder, and the mixture is sucked into the cylinder during the intake stroke. Adopting this technical route, in the intake stroke of the engine, most of the time in the intake pipe is filled with the mixture of gas and air, which is easy to cause backfire and cause safety accidents. In order to reduce the possibility of tempering, the gas engine with this inta...

AI Technical Summary

Problems solved by technology

Only during the injection period, the air is mixed with the gas and enters the cylinder through the intake valve. Most of the time, pure air enters the cylinder, and the air and gas are not mixed uniformly.

When transitioning from a small load to a large load, the gas demand per cycle of the gas machine suddenly increases. Although the injection duration of the gas nozzle can be extended in time through the control unit, there is a delay in the subsequent gas replenishment, and the pressure in the gas pipeline is reduced. As a result, the amount of gas injected into the cylinder cannot respond to the demand of the gas engine in time, which affects the overall performance of the engine and the responsiveness to changes in working conditions

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