What is the working principle of power steering?

[Saul]

Working principle of power steering: When the car is steering, the torque sensor detects the torque and rotation direction of the steering wheel, and sends the signal to the electronic control unit. The electronic control unit comprehensively analyzes the data such as the torque of the steering wheel, the rotation direction and the vehicle speed, and sends signal instructions to the motor controller, so that the motor outputs the corresponding size and direction of torque to generate power assistance. The power steering system of the car is roughly divided into two categories: hydraulic and electric. The power assistance principle of the electronic hydraulic power steering system is the same as that of the traditional mechanical hydraulic power steering system, but an electric steering pump is added. The start and stop of the electronic pump are controlled by the ECU. When no steering action is performed, the electric steering pump is turned off, unlike the mechanical hydraulic power steering pump, which is always linked to the engine through a belt.

[LeGideon]

I've driven many cars before, and the power steering system makes turning the wheel effortless. Its working principle mainly involves amplifying the driver's force through a power-assist mechanism. Taking the most common old-fashioned hydraulic power steering as an example, when you turn the steering wheel, it drives a torsion bar or gear system, while sensors or mechanical devices detect this motion. A hydraulic pump connected to the engine generates oil pressure, which is then delivered through pipelines to the steering gear, pushing pistons or similar components to assist your effort. This way, even if the steering wheel is heavy, you can still turn easily. Nowadays, many new cars use electric power steering, where a motor directly provides assistance, making it more fuel-efficient and reliable. This evolution makes driving safer, especially during high-speed driving or turns, preventing driver fatigue. If you've driven older cars for a long time, you'll realize the importance of the power steering system—without it, the steering wheel feels as heavy as a rock, making it much harder for beginners. This thing is actually quite amazing, making everyday driving as easy as playing a game.

[LaMarley]

Speaking of power steering, I often encounter this system while working on cars. It assists driving through a combination: when you turn the steering wheel, sensors or linkages detect your input force, and then the control unit commands the hydraulic pump or electric motor to apply additional power. The hydraulic system relies on fluid pressure for assistance, while the motor system is more intelligent, calculating the required assistance in real-time. This design not only enhances maneuverability but also prevents steering failure risks. For example, during sharp turns or parking maneuvers, it responds instantly, reducing the effort you need to exert. Modern vehicles mostly use electric power steering due to its high integration, reduced risk of oil leaks, and simpler maintenance. In daily use, if the power assistance fails—like in an older car I encountered—the steering wheel becomes extremely heavy, making driving dangerous. Therefore, regular checks of the pump or motor are crucial. This system truly makes driving safer and more comfortable.

[McJoy]

I noticed that power steering is an essential feature when driving. It relies on sensors to detect the rotation of the steering wheel and then provides auxiliary power through a motor or hydraulic system. Simply put, when you turn the wheel, the system automatically adds force to make steering easier. This is thanks to internal electronic control, which works like calculating the required assistance level. For new drivers, this design makes parking and turning less stressful, avoiding many mistakes. In real-world scenarios, such as low-speed maneuvering, it would be very difficult to operate without power steering. Nowadays, cars come standard with this system, improving the overall driving experience and safety factor. Just think about it—with effortless steering, you can focus more on the road conditions.