The generator is inline with the driveline and acts as an electric retarder. The generator also provides more horsepower defined in Kilowatts to help the diesel engine with added torque up to 30 mph.
The Computerized Control Unit (CEU) monitors the loads and speeds and sends amperage to the generator from the battery pack to provide braking then allows the generator to recharge the battery pack when the bus is going downhill in the coast mode. Light braking also helps charge the battery pack.
The generator is water cooled (long life antifreeze) and has a coolant pump to circulate the coolant through the generator body then it returns to the radiator which is specifically for the hybrid system.
The radiator is mounted below the driver's area and has an electric fan that is controlled by the CEU. The coolant pump is also monitored and operated from the computer. The more stop and go driving creates more heat in the generator but creates maximum torque/Horsepower/Kilowatts out of the hybrid system.
The battery pack has a main switch that must be turned off when working on the system. The batteries are lithium Ion and weigh far less than previous hybrid systems. They were manufactured in Korea and ENOVA (the developer of this hybrid system) reported very positive testing results with these batteries. The orange covering on the cables indicate high voltage and should be handled with care and properly insulated gloves.
Previously the battery pack used to be liquid cooled. This caused some minor problems with leaks and maintenance. Now ENOVA has developed an air cooled system that has a standard paper type filter with a high output blower inside the battery case that is funneled throughout the battery pack and exits out the rear of the aluminum encasement (towards the frame).This has been a short over-view of the International School Bus Hybrid Diesel Engine. Please feel free to make any comments & thanks for stopping by...
