Drive system with expander shut off upon detection of a leak

An operating method of a drive system comprising:

• providing an internal combustion engine and an expander operated via a combustible working medium;
• a power transmission coupling disposed between a crankcase of the internal combustion engine and the expander;
• at least one of a first seal disposed between the expander and the power transmission coupling and a second seal disposed between the power transmission coupling and the crankcase;
• a crankcase ventilation line leading from the crankcase into an intake pipe of the internal combustion engine;
• an air mass sensor disposed in the intake pipe upstream of a junction of the crankcase ventilation line;
• an engine control unit operatively connected to the air mass sensor, the expander and the internal combustion engine;
• and
• monitoring a power of the internal combustion engine and an air mass flow from the air mass sensor via the engine control unit, and shutting off the expander in response to detecting a sudden power rise in the internal combustion engine while the air mass flow remains constant to reduce a passing of the combustible working medium from the expander into the internal combustion engine.

A drive system comprising:

• an internal combustion engine;
• an expander operated via a combustible working medium;
• a power transmission coupling disposed between a crankcase of the internal combustion engine and the expander;
• a working medium sensor disposed in the power transmission coupling;
• a first seal disposed between the expander and the power transmission coupling and a second seal disposed between the power transmission coupling and the crankcase;
• a crankcase ventilation line leading from the crankcase into an intake pipe of the internal combustion engine;
• an air mass sensor disposed in the intake pipe upstream of a junction of the crankcase ventilation line;
• an engine control unit operatively connected to the air mass sensor, the expander, and the internal combustion engine;
• the engine control unit configured to detect a power of the internal combustion engine and an air mass flow from the air mass sensor and shut off the expander when the power of the internal combustion engine detected suddenly rises and the air mass flow remains constant to reduce a passing of the combustible working medium from the expander into the internal combustion engine.