Toyota Hybrid System (THS)

The hybrid system is a type of powertrain that uses a combination of two types of motive forces, such as an engine and a motor (MG2). This system is characterized by its skillful use of two types of motive forces according to the driving conditions. It maximizes the strengths of each of the motive forces and complements their weaknesses. Thus, it can achieve a highly responsive, dynamic performance, as well as a dramatic reduction in fuel consumption and exhaust gas emissions. The THS can be broadly divided into two systems: the series hybrid system, and the parallel hybrid system.
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Series Hybrid System
In the series hybrid system, the engine runs a generator, and the generated electricity enables the electric motor to drive the wheels. This type of vehicle can be described as an electric car that is equipped with an engine-driven generator. Equipped with a low-output engine, the engine is operated at a practically constant speed in its most effective range, in order to efficiently recharge the battery while the vehicle is in motion.
Parallel Hybrid System
This system uses both the engine and the electric motor to directly drive the wheels is called the parallel hybrid system. In addition to supplementing the motive force of the engine, the electric motor in this system can also serve as a generator to recharge the battery while the vehicle is in motion.

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