Patent ID: 7654247
Filing Date: 2010-02-02
Classification: F02B,F02D,F02M,F02N,Y02T

Abstract:
1. A method of controlling starting of a gas engine in which fuel gas is introduced via a fuel gas flow control valve to a charging air supply pipe to be mixed with air and the mixture is controlled in its flow rate by a throttle valve and supplied to combustion chambers of the engine, the method comprising: a starting operation mode in which fuel gas flow is controlled by the fuel gas flow control valve based on actual mixture flow rate and adequate excess air ratio prescribed for each of detected values of operating conditions of the engine and then mixture flow is controlled by the throttle valve so that engine rotation speed approaches a target rotation speed; and a normal operation mode in which fuel gas flow is controlled by the fuel gas flow control valve so that engine rotation speed approaches the target rotation speed and then mixture flow rate is controlled by the throttle valve so that air fuel ratio of the mixture coincides with an adequate value prescribed for each of detected values of operating conditions of the gas engine with the fuel gas flow flowing at a commanded fuel gas flow rate, wherein a switchover rotation speed is a predetermined threshold value of engine rotation speed for the engine to be able to run self-reliably, and wherein the engine is controlled in the starting operation mode during engine rotation speed from a prescribed initial rotation speed to a prescribed switchover rotation speed, and when the rotation speed rises to equal to or exceeds the prescribed switchover rotation speed, the control is switched to the normal operation mode.