What is the working principle of hybrid electric vehicles?
3 Answers
Hybrid electric vehicles work by utilizing both the internal combustion engine and the electric motor within the vehicle to provide power, thereby driving the car forward. This results in certain improvements in fuel economy, comfort, and acceleration. Hybrid electric vehicles use an electric motor as an auxiliary power source to assist the engine in driving the car. The electric motor can generate strong and smooth power during normal driving. The engine and the electric motor have complementary roles. If the engine is operating in its optimal state, the engine works alone. If the engine is not in its optimal state, the electric motor begins to assist. The goal is to keep the engine operating in its optimal state at all times, thereby achieving the lowest fuel consumption. Hybrid electric vehicles combine fuel and electric power. The electric motor delivers strong torque at low speeds, providing power for vehicle start-up and acceleration. As the speed increases, the internal combustion engine's output power and torque continue to rise, providing power for mid-to-late-stage acceleration.
After driving a hybrid car for a while, I've found it to be incredibly smart. At startup, it relies solely on the electric motor, as quiet as an electric vehicle; in traffic jams, the engine simply shuts off, using battery power to inch forward without consuming any fuel. Only during highway cruising does the engine kick in, simultaneously topping up the battery. The most impressive part is when braking downhill—the kinetic energy recovery system quietly stores energy back into the battery, which can then be used for the next acceleration. This seamless coordination halves fuel consumption, with my car using just over 4 liters per 100 kilometers. With reduced engine operation time, noise levels naturally drop as well.
The core of hybrid technology lies in the energy management computer, which dynamically allocates the proportion of gasoline and electric power usage. At low speeds, it operates solely on electric drive to avoid inefficient engine operation; during rapid acceleration, both the motor and engine work in tandem; deceleration triggers regenerative braking to recover energy. The battery acts like an energy reservoir, charging when the gasoline engine operates efficiently and discharging when extra power is needed. This synergy breaks through the traditional thermal efficiency limit, with Toyota's THS system achieving a thermal efficiency as high as 41%. The battery requires only about 1 kWh, utilizing nickel-metal hydride batteries to balance cost and durability.
