Control of an impeller clutch of a torque converter for a gaseous fuel engine

A transmission system, comprising:

• a gear system configured to couple to a hydraulic fracturing pump;
• and
• a torque converter configured to fluidly couple a gaseous fuel engine and the gear system, the torque converter comprising:
• an impeller;
• a turbine fluidly coupled to the impeller and mechanically coupled to the gear system;
• a stator positioned between the impeller and the turbine;
• an impeller clutch configured to mechanically couple the impeller to the gaseous fuel engine;
• and
• a lockup clutch configured to mechanically couple the gaseous fuel engine and the gear system;
• and
• a controller configured to:
• cause disengagement of the impeller clutch;
• and
• cause an upshift of the gear system based on disengagement of the impeller clutch.

A torque converter to fluidly couple a gaseous fuel engine and a gear system mechanically coupled to a hydraulic fracturing pump, the torque converter comprising:

• an impeller;
• a turbine fluidly coupled to the impeller;
• a stator positioned between the impeller and the turbine;
• an impeller clutch configured to couple the impeller to the gaseous fuel engine;
• and
• a lockup clutch configured to mechanically couple the gaseous fuel engine and the gear system;
• and
• a controller configured to:
• cause disengagement of the impeller clutch;
• and
• cause an upshift of the gear system based on disengagement of the impeller clutch.