Gas engine, gas heat pump device and cogeneration device that use gas engine, and method for controlling gas engine

摘要

Provided are: a gas engine that is capable of smoothly switching between a stoichiometric operation and a lean operation; a gas heat pump device and cogeneration device that use the gas engine; and a method for controlling the gas engine. The gas engine (1) performs a stoichiometric operation during high loads, and a lean operation during low to medium loads, and a valve (2) for supplying a mixture of air and fuel gas to the gas engine (1) controls the valve opening area of a stoichiometric valve part (21) and a lean valve part (22) in series by connecting the stoichiometric valve part (21) to a mixer (24) side in such a manner that a certain opening area for achieving the stoichiometric operation is ensured, and until an operation for switching from the stoichiometric operation to the lean operation is completed, the opening area decreases uniformly over time, and a certain opening area for achieving the lean operation is ensured, and until an operation for switching from the lean operation to the stoichiometric operation is completed, the opening area increases uniformly over time.