ABSTRACT
Hybrid vehicles have multiple power sources that can be separately or simultaneously used to propel the vehicle. Different ways of integrating these power-producing components with electrical energy storage components allow for distinct types of hybrid electric vehicle configurations. During low-power driving conditions, the internal combustion engine (ICE) produces more power than needed to drive the vehicle. Generally, fuel energy may be converted by a number of distinct heat engines, such as an ICE, while an electrical motor derives its electrical energy from batteries, ultracapacitors, solar cells, fuel cells, or generators driven by heat engines or flywheels. When the state of charge (SOC) reaches the minimum level, the ICE will be triggered to drive the generator to recharge the battery back to its maximum SOC. When the power demand is greater than the maximum ICE output power at current engine speed, the ICE output power is set to the maximum available power at current engine speed.
