Method and system for prechamber operation during catalyst heating

The present disclosure provides methods and systems for prechamber operation during catalyst heating. Methods and systems are provided for operating a pre-chamber to provide ignition to a cylinder during catalyst heating. In one example, a method may include, in response to a temperature of a catalyst being less than a threshold temperature, injecting fuel and air into a pre-chamber of an engine cylinder during an expansion stroke of the engine cylinder; and in response to the temperature of the catalyst being greater than or equal to the threshold temperature, injecting the fuel and the air into the pre-chamber during a compression stroke of the engine cylinder. In this manner, the pre-chamber may provide robust ignition to the cylinder during various operating conditions. 本公开提供了"用于在催化剂加热期间进行预燃室操作的方法和系统"。提供了用于在催化剂加热期间操作预燃室以向气缸提供点火的方法和系统。在一个示例中，一种方法可包括：响应于催化剂的温度小于阈值温度，在发动机气缸的膨胀冲程期间将燃料和空气喷射到所述发动机气缸的预燃室中；以及响应于所述催化剂的所述温度大于或等于所述阈值温度，在所述发动机气缸的压缩冲程期间将所述燃料和所述空气喷射到所述预燃室中。以此方式，所述预燃室可在各种工况期间向所述气缸提供稳健的点火。