Differences between power steering and electric power steering?

Automakers do everything to make driving a car comfortable and enjoyable. This applies to literally everything in the car, including the steering. The steering wheel should turn easily, without effort, and not with difficulty, as it was in the old days on older vehicles.

Currently, it is difficult to imagine a car without power steering, that is, a special device that helps turn the wheels of the car. Many people know that there are two types of such amplifiers: hydraulic, that is, driven by hydraulics (power steering), and electric, operated by an electric motor (EUR). Let's see what is the difference between power steering or electric power steering?

Power steering operating principle

Hydraulic power steering column rotation appeared in the last century and was initially installed only on trucks. It's clear. Driving a multi-ton vehicle is much more difficult than driving a passenger car. However, over time, automakers began to use power steering, including on passenger cars, thereby increasing their attractiveness compared to other brands. Currently, approximately 60% of new machines are equipped with hydraulics.

Power steering is a rather complex mechanism consisting of several elements: - a pump connected by a belt drive to the engine crankshaft; — reservoir for hydraulic fluid; — a piston installed in the steering rack; — a hydraulic distributor that sets the direction of movement of the piston.

All these elements are connected to each other by metal tubes containing hydraulic fluid. Its task is to transfer the pressure created by the pump to the piston, which then pushes the rack shaft and in this way helps to turn the wheels of the car. In general, power steering works as follows.

After the car engine starts, a pump rotated by the crankshaft builds up pressure in the system. As long as the driver does not turn the steering wheel, excess pressure is released into the expansion tank. When you try to turn the steering wheel of a car, the distributor opens the desired line and directs the fluid into one of the chambers located on the right or left side of the piston.

Under pressure, the piston moves and pushes the steering rack shaft simultaneously with the rod attached to the front wheel steering knuckle. This significantly reduces the amount of effort required by the driver to turn the steering wheel.

If the steering wheel of the car is turned in the other direction, the distributor will close the first line and open the second, pressure will arise in the other chamber and the piston will move in the opposite direction.

Operating principle of the EUR

Electric power steering was introduced later than hydraulic power steering and began to be widely used only after 2000, gradually conquering the world automobile market.

Both of these mechanisms perform the same function - they make it easier for the car owner to steer the car. However, the difference between them is that the power steering moves the rack shaft using a special electric motor, and the power steering using a pump and hydraulic fluid.

In this case, the engine in the electric power steering is controlled by a separate electronic unit (ECU). The operating principle is as follows:

After starting the engine, voltage is supplied to the control unit, but the EUR is not yet active at this time. After the slightest turn of the steering wheel, this movement is detected by a special sensor, which transmits an impulse to the ECU. Based on the sensor signal, the controller commands the electric motor to rotate the steering shaft in one direction or another through a gear transmission.

Pros and cons of power steering

Power steering has a number of advantages, thanks to which it was once widely used in the automotive market. Here are the most important ones:

- lower production costs, which in turn affects the final price of the new car; — thanks to the use of power steering, you can get more power, which is necessary when operating heavy trucks and minibuses; — reliable design of the hydraulic booster, which has been tested over years of use.

However, power steering also has disadvantages. The main one is the need to control the fluid level in the system and the frequency of maintenance. It is necessary to ensure that the seals of the piston mechanism, distributor and pump do not leak, change and tighten the belt in time, and lubricate the bearings.

Among other disadvantages, which are less significant, is a slight increase in fuel consumption due to the fact that the power steering pump works constantly while the engine is on.

Advantages and disadvantages of electric power steering

Compared to power steering, an electric amplifier has a number of advantages:

— such a system, including an electric motor and a control unit with a sensor, does not require regular inspections and maintenance; — smaller dimensions of the mechanism, that is, it does not take up much space; — The electric power steering does not consume electricity unnecessarily and, it turns out, does not consume additional fuel.

Electric power steering also has other advantages, for example, those related to changing its operation settings depending on driving conditions. In addition, the ESD is used in modern premium cars because it can be controlled by an on-board computer.

The main disadvantage of an electric amplifier is its high price. The higher the cost of the mechanism and its elements, the more expensive the repair will be. Often a failed EUR has to be completely replaced. In addition, the electric booster has less power, making it difficult to use for trucks and heavy vehicles.

Which power steering is better?

Experience shows that both amplifiers are quite reliable in operation. Although breakdowns occur with both. When choosing between power steering or electric steering, it is necessary to consider each situation separately: what kind of car, what budget does the driver have, etc. It's up to you to decide, and the characteristics of each are given above.

It is only worth noting that electric power steering is constantly being improved and is displacing hydraulics from the market thanks to a more modern and simpler design. Perhaps over time their cost will be reduced and their power will increase.

Tagged,

Almost all modern cars, in particular foreign cars, are equipped with power steering. Today, there are two types of amplifiers: electric and hydraulic, and each of them has its own pros and cons.

Let's figure out what the main differences between power steering and electric power steering are. How do they differ, and which one is more reliable? Let's start with the most common type - power steering

, that is .

Power steering (power steering).

Power steering uses ATF oil, which is also used in automatic transmissions. The hydraulic booster works like this: under high pressure, the pump pumps oil into the distributor. The task of this distributor is to monitor and dose the forces on the steering wheel. Together with it, a torsion bar installed on the steering shaft works.

So, what are the advantages of power steering?

The first advantage is that power steering provides excellent feedback to the road.

The second advantage of this device is comfort. After all, everyone knows that a car with a hydraulic booster installed in it is much easier to drive. Whatever the speed.

Third, it applies more to modern amplifiers. They install electric pumps that no longer have a belt drive.

But nothing in this world is perfect, and power steering has its drawbacks.

One of the main disadvantages of power steering is that it requires very careful handling in winter.

. And if the unexpected happens - the device leaks, you need to immediately fix the malfunction, since the car, with such a breakdown, can no longer be used. Otherwise, the pump that heats the oil may also break. Therefore, immediately go to a car service center if this happens.

The next drawback is the need to change the oil after a certain number of kilometers.

If your power steering is belt type, this increases fuel consumption as it puts additional stress on the engine.

Dimensions are another drawback. Due to its design, the power steering takes up an impressive space under the hood.

Also, the disadvantages of the hydraulic booster include the complexity and high cost of repair and maintenance.

Comparison of power steering and power steering

When trying to figure out whether an electric booster or a hydraulic booster is worth using, you need to compare them to understand what their fundamental differences are. So, power steering is a very bulky and massive device. As for the EUR, it is compact in size and easy to install. Due to the complex design of the power steering, difficulties often arise with its repair. For example, to replace a belt, you first need to get to it. And to do this you need to remove the power steering pulley.

The power steering differs in that it operates in constant mode. Because of this, it wears out quite quickly. There is no such problem with the EUR. It turns on only at the right moment.

Another difference between power steering and electric power steering is that power steering requires regular maintenance. It is necessary to change the fluid in it periodically. You should also replace worn out oil seals with new ones to restore the tightness of the system. There are no consumables in the EUR, so their replacement is not required. This eliminates problems with servicing the amplifier.

It is also important to remember that if your car has power steering, the steering wheel should not be kept in the extreme position for too long. The duration of this state should not be more than five seconds. Otherwise there is a risk of problems arising. With EUR they are excluded.

Electric power steering (EPS).

Now, let's move on to the EUR, that is, the electric power steering. It works using electric current, as is clear from its name.

Compared to the hydraulic booster, there are no fluids whose levels would have to be monitored. The EUR does not work all the time, but only when turning. It makes less noise and the whole operation is controlled by sensors.

First of all, the advantages of an electric booster include its excellent connection with the road.

The EUR has two modes of use: urban and highway. It is easier to drive in city mode. If the device was operating in highway mode, then already at fifty kilometers, it will automatically switch back,

An important advantage of the EUR over the hydraulic booster is that it does not use liquids, which makes it possible to avoid servicing it at all.

Since the electric booster has no belt structures and is powered by a generator, this does not create additional loads on the engine.

This device takes up less space under the hood. After all, an electric booster is a much simpler device than power steering.

Repairing the EUR, although expensive, is not that difficult. And if a breakdown occurs, you can continue on your way, although the steering wheel will become a little heavier. But this will not prevent you from calmly reaching your destination, and slowly going to the auto repair shop.

As for the minuses, there is only one. Since electricity is used to power the EUR, the car requires a more powerful generator.

So, we have looked at the main differences, as well as the pros and cons of power steering and electric power steering. I think the choice is obvious. Over time, the EUR will gradually displace its competitor, which, in principle, is fair.

Nowadays it is almost impossible to find a car that is not equipped with one or another power steering. However, now there are two large classes, this is the hydraulic system, if abbreviated as “GUR”, and the electrical system – “EUR”. They can be installed equally on the same model! But which one is better? What are the advantages of one over the other? And what to choose so that it can last for a very long time and not break. We'll figure it out today. Plus a video version and voting at the end, so it will be interesting...

In this article I will not talk in detail about how this or that system works, yet I already have a lot of articles about this. WE will think about which option is currently simpler, better, more accurate and more durable.

Which option is better? Hydraulic or electric power steering?

Both technologies do their jobs well. However, power steering is more suitable for large cars that require serious driving effort. And the electric booster is ideal for medium and small cars that do not have the mass to apply serious hydraulic technology to them. In addition, the electric booster is cheaper and smaller in size! Fuel economy in this case comes first.

Experts say that the amplification system has no particular disadvantages. Although every driver must take into account one nuance - if you twist the steering wheel all the way, the electric power steering may burn out. Therefore, you should drive the car carefully, avoiding extreme situations and actions. The hydraulic booster does not have such features.

Some drivers ask questions about the feasibility before installing the system. As a rule, it is installed directly at the car manufacturing plant. But in home-made conditions, it will not be possible to implement an additional option.

Do I need to buy a car with hydraulic or electric power steering? Undoubtedly, yes! Professional motorists do not recommend even looking at models that are not equipped with such amenities.

Power steering (hydraulic system)

It’s worth starting with this option, because it was the first to appear on cars and has still not lost its relevance.

Principle of operation

: Very simple, here the main working fluid is a special liquid, which is often poured into. The steering rack itself is a hollow cylinder into which a piston goes, attached to the steering shaft (to exaggerate it, it looks very much like a pharmaceutical syringe). A special pump pumps oil pressure in one direction or the other, and this piston begins to deviate in one direction or the other, accordingly helping you turn the steering wheel. There is approximately 0.5 - 1 liter of oil in the system, it is pumped by a pump that is driven by the engine crankshaft, that is, they are connected by a belt drive. Of course, the system contains metal and rubber tubes through which the working fluid actually pumps.

Due to the rigid connection, the motor power is reduced, because part is simply eaten by the pump!

A few words about EGUR

. That's why electric power steering is now starting to appear. What does it mean? The differences are few, but they are significant - here, instead of a belt pump, an electric motor is used, that is, electricity is simply supplied and it pumps oil in the system. Thus, taking much less power and saving up to 0.5 - 0.7 liters per 100 km. Well, now it’s time to think about the pros and cons of this device

Pros of GUR

Controllability. The driver has good feedback from the road; in terms of response accuracy and response, power steering comes first
Great effort. Such amplifiers are installed on many HEAVY trucks; all electrical systems are not yet fully adapted

Comfortable handling at both low and high speeds
Now there are new generation devices with electric pumps that do not use a belt drive and save fuel
There are no complex electronic sensors, we can call this system analog (except for power steering)
Reliability is at a fairly high level, if you monitor it and change it on time, it can last a very long time

In general, there are not many complaints about this system; it still works stably, accurately and, importantly, can “turn” heavy truck racks. However, there are also a lot of negative aspects

Cons of GUR

Takes up quite a lot of space under the hood (pipes, pump, rack itself) all this is quite cumbersome
It has a special oil that needs to be changed after a certain number of kilometers, otherwise it may break down. Because oil seals can wear out faster

If the model is old (belt), it increases fuel consumption by up to 10% (if compared with the opponent). Because it additionally creates a load on the engine (pressure is built up thanks to a belt drive that comes from the crankshaft, respectively, part of the engine energy is spent on the hydraulic booster). Even at idle

At low temperatures, you need to use it more carefully, it is advisable to warm it up
If there is a leak or oil has leaked out, then you cannot operate the car! Or very limited mileage. Otherwise, the pump itself that pumps the oil may break.
Repairs are sometimes very expensive. Although almost all service stations do this, there is nothing particularly complicated here

As you can see, the disadvantages of this system are also significant, especially power take-off and fuel consumption. After all, if you have a small-volume engine, it’s already “dead,” and then it also takes away the hydraulic booster.

Design features of hydraulic and electric booster

Power steering is a closed system that operates due to the fluid circulating in it.
The design includes a pump, reservoir and connecting hoses. The system works thanks to the action of a piston pump, which is driven by the crankshaft of the car. As a result, high pressure is created, which through the liquid (oil) transmits force to the distribution mechanism. The latter is a torsion bar built into the steering shaft. As soon as the steering wheel begins to rotate, oil channels open in the system, the pump rod begins to move and a force is created, which is transmitted to the wheels through a complex system of levers. The electric booster, thanks to the presence of a sensor, starts working at the slightest turn of the steering wheel. In this case, voltage of different polarities is supplied to the electric motor, depending on the direction of rotation (right or left). The task of the second sensor is to regulate the current strength depending on the force applied to the steering wheel, which helps to avoid emergency situations. During slow turns, the electric motor almost “sleeps”, but during sudden movements it immediately turns on, helping the driver to cope with control more efficiently.

EPS (electric power steering)

It was created as a more advanced and simpler system (and is still being improved). It has a lot of varieties, at least read it.

Principle of operation

: Again, in a nutshell - everything is simply taken by an electric motor, connected to a shaft (on which there are special grooves, or a screw, or just splines) and this electric motor pushes this shaft to the right or left.

The only difference between electric amplifiers is that the electric motor can be attached to different parts of the steering mechanism:

On the steering column
On the rack shaft itself (I use a spline connection)
Parallel to the steering column shaft (twin shaft systems)
Using a ball nut

Ask why there are so many different mechanisms - it’s all because you haven’t yet achieved the normal effort and accuracy of “steering” like your opponent. Although the last type with a ball nut came very close to this.

Of course, the EURA has no liquid, no hoses and tubes, no pump - it is very compact, which often allows it to be mounted even on the steering column.

However, the negative side here is the presence of various sensors and other electronics, but everything is in order

Positive aspects of the electric booster

The driver has sufficient effort and contact with the road
Has two positions. City and highway. In city mode, the steering wheel is lighter, which contributes to comfortable driving. In the “road” mode, it turns off already at 40–60 km/h, which was done on purpose; at high speeds, an amplifier is not needed. Therefore the feedback is increased.
Fuel economy. There is no additional load on the engine because it has no belt drives and is powered by electricity from a generator (battery). If the car is stationary and the steering wheel does not turn, it does not work. Activated only when turning. Allows you to save up to 10% fuel
It takes up little space under the hood and in the cabin. Since it is technically simpler (and more compact) than power steering

It has no liquid and, accordingly, is practically maintenance-free
Has a wide temperature range of use. For example, in winter there is no need to heat it. Even a few seconds
If it breaks, you can move freely, but the steering wheel will become heavier, at least you will always get to the service station
Many electronic autopilot (autoparking) systems work only with electric power steering
AT THE MOMENT - RELIABLE, not inferior in quality to the hydraulic booster

As you can see, there are really a lot of positive aspects, some of them don’t even know that they have an electric booster until it reaches 150 – 200,000 km, because there are simply no cans or other parts under the hood. I like that lately it has been tuned quite precisely, that is, it is beginning to be similar in “steering” accuracy to its opponent. However, it is still far from it, yet there are also a lot of disadvantages here

Negative points of EURA

Repairs are expensive and difficult to diagnose. Ordinary service stations often simply do not know what is broken, there are simply oxides on the contacts and such an amplifier is already faulty. You need special diagnostic tools to read errors. Also, the blocks here are often not repaired, but replaced as an assembly. If the engine is damaged, it is often cast with either a steering rack or a column; they are replaced together. AND THIS IS EXPENSIVE!

If moisture gets under the protective covers, it may malfunction.
Since it uses electricity, it requires the installation of a more powerful generator and complex wiring
The first models sometimes “glitched”, turned in the wrong direction, and did not work clearly. True, this only happened on our VAZs

Design and principle of operation of electric power steering

Electric Power Steering (EPS) is another power steering technology. The main reason why global automakers use it is fuel efficiency. EPS uses an electric motor to assist the driver, unlike traditional systems that rely on hydraulic pressure generated by a pump driven by the vehicle's engine. This pump is constantly running regardless of whether the steering wheel is turned or not. This constantly increases the load on the engine, which negatively affects fuel consumption.

By switching to an electric motor, the load on the engine is reduced only when the steering wheel is turned to one side or the other, resulting in better fuel economy. An electric motor, which is mounted on the steering column or on the steering gear (nowadays, rack and pinion gear is usually used), supplies torque to the steering column, helping the driver turn the steering wheel. Sensors detect the position of the steering wheel and any signals received from the driver when he turns the steering wheel to change the direction of the car. The control module supplies auxiliary torque via the electric motor. If the driver simply holds the wheel stationary in a straight-ahead position, the system does not provide any assistance.

EPS not only offers the benefit of improved fuel economy, but also has several other features. Being electronic and computer configurable, the EPS system can be programmed for many different situations.

Engineers can now program variable assistance in different modes. For example, when parking, maximum assistance makes it easier to maneuver in and out of parking spaces, but at higher road speeds the steering assistance is reduced to improve vehicle stability. With little resistance built into the steering at high speeds on the open road, the car is less likely to become unstable due to excessive driver input.

Electric power steering appears in more and more cars every year. These systems can be found on a variety of vehicles, from trucks to small cars. Electric power steering has a bright future as autonomous and active safety systems are developed to steer the car with minimal user intervention.

Diagnosing electric amplifiers requires an understanding of voltage, current, and load. Additionally, the technician must understand how the modules and sensors work to determine the level of assistance.

Electric amplifier device

Motor

Most electric power steering systems use a three-phase electric motor that operates on DC voltage with pulse width modulation. The motor is brushless and has an operating voltage range from 9 to 16 volts. Three-phase motors provide faster and more precise application of torque at low speeds.

The motor uses a rotation sensor to determine its position. On some systems, if the module is replaced, the end stops (stops) must be checked to ensure that the motor does not move the rack beyond the maximum rotation angle. Such a service may be an additional step in calibrating the steering angle sensor. The engine can be connected to the steering rack or column. Today, more and more cars use motors that are mounted on the base of the steering box or on the opposite end of the rack.

Module

The electric power steering module is more than just a circuit board and connectors in an aluminum box. The module contains drivers, signal generators and MOSFET switches that power and control the motor. The module also contains a current monitoring circuit that measures the amplifiers used by the motor, as well as a current monitor and other inputs to determine the motor temperature using an algorithm, even taking into account the ambient temperature.

If the system detects a condition that could cause the motor to overheat, the module will reduce the amount of current flowing to it. The system can go into fail-safe mode, generate a fault code and alert the driver with a warning light or message.

Touch sensors

For electric power steering systems, the main information is provided by measuring the steering angle and steering speed. The scan tool typically displays this information in degrees. The steering angle sensor (SAS) is usually part of a group of sensors in the steering column. There will always be more than one steering position sensor in the sensor block. Some sensor clusters have three sensors to validate the data. Some SAS clusters and sensor modules are connected to a controller area network (CAN) bus. The SAS module or cluster can be connected directly to the ABS/ESC module on the CAN bus, or can be part of a common CAN network in a circuit that connects various modules in the vehicle.

The steering wheel torque sensor measures the force applied by the driver and provides sensitive control of the electric power steering support. It performs the same function as a spool valve in a hydraulic steering system.

Touch sensor

RESULT

It seems to me that progress is inexorably moving towards electric amplifier options, this is inevitable. If only because all modern systems, such as “steering” and keeping the car in the lane, auto parking, and other autopilots cannot work with the hydraulic version, it simply does not have an electric motor that they can control! Also, the EUR is more economical, less fuel is consumed, which is very important for the environment. Its reliability is the same, that is, both options can last a long time. That is why now many manufacturers, not only European, but also Japanese and Korean, are switching to electric units in passenger cars.

It is difficult for a modern driver to imagine that just a few decades ago vehicles were not equipped with power steering. This equipment began to be installed en masse on passenger cars only in 1952. Today, the most popular are two types of systems that reduce control force: hydraulic power steering (power steering) and electric power steering (electric power steering), but few people know the difference between electric power steering and power steering.

Power steering and power steering perform the same tasks, namely:

make the process of driving a vehicle easy and comfortable,
reduce the force of impacts that are transmitted to the steering wheel while driving on poor road surfaces,
increase the level of active safety of the machine.

How does power steering work?

Power steering is a complex and well-designed mechanism. In order to understand the principle of its operation, you need to understand the following questions: what elements are included in its composition and how they work.

Pump connected to the oil reservoir. Its task is to create and maintain a certain pressure in the system.
A pressure regulator (distributor) that forces oil to flow into one or another section of the power hydraulic cylinder.
A hydraulic power cylinder that rotates the piston rod under the influence of oil pressure.
Oil lines through which fluid continuously circulates.

The entire time the vehicle is driving on a straight road, the power steering fluid is in a reservoir that is connected to the pump. After the driver begins to rotate the steering wheel, the pump pumps fluid into a hydraulic cylinder, which, under the influence of increasing pressure, moves the piston, significantly reducing the amount of force required to turn the steering wheel.

Electric power steering

When the driver turns the steering wheel, a special sensor is triggered. Depending on which direction the steering wheel was turned, the sensor supplies a current of a certain polarity to the electric motor, which, depending on the polarity, helps rotate the steering wheel in one direction or another.

The sensor also takes into account the force applied by the driver to the steering wheel and regulates the power of the current supplied to the electric motor. Thus, if the driver turns the steering wheel slowly, for example when entering a long turn, the assistance of the electric motor is small.

When the steering wheel turns quickly, the electric motor helps more effectively. Also in the electric power steering system there is a speed sensor, which also regulates the power of the supplied current to avoid emergency situations.

How does EUR work?

For the electric booster to operate, it is necessary to coordinate the interaction of a number of mechanisms operating under the control of the ECU and two measuring transducers (sensors) that record the angles of rotation and the amount of engine torque. As the steering wheel rotates, information about the amount of torque is recorded and processed by a sensor, which sends it to the electronic control unit. In turn, the ECU, based on the data received, calculates the amount of current that will be supplied to the electric motor to ensure easy and comfortable rotation of the steering wheel.

Pros and cons of electric and hydraulic power steering

Positive qualities of power steering.

The main advantage of hydraulic power steering is their relatively low cost. It is thanks to this factor that inexpensive budget cars are most often equipped with these mechanisms.

Hydraulic boosters have a good power reserve. It is advisable to install them on off-road vehicles and minibuses, because These devices are able to withstand long-term exposure to high external loads.

Negative qualities of power steering.

Owners of vehicles equipped with hydraulic power steering should remember that the steering wheel should not remain in the extreme right or extreme left position for more than 4-5 seconds. Exceeding this time limit may cause the system oil to overheat with further failure.

Experts say that the power steering must be serviced periodically. The fluid circulating in the system must be replaced regularly. It is also necessary to inspect the surfaces of all its constituent elements. If during their visual inspection cracks or traces of fluid leakage are detected, then it is necessary to immediately replace the part that has become unusable with a new spare part.

During its operation, the hydraulic power steering necessarily takes a certain percentage of power from the engine.

As the driving speed increases, the speed of the power steering response to the actions of the vehicle driver decreases. This is explained by the presence of additional components that slow down the device’s response to steering wheel rotation.

Positive qualities of the EUR.

The simple and effective design of the electric power steering is devoid of any additional components. Periodic maintenance of the electric power steering does not require time or material costs because comes down only to checking the functionality of the rolling bearings.

Small dimensions are a distinctive feature of the electric amplifier. Due to its modest size, it is mounted directly on the steering shaft, and not in the engine compartment of the car. This arrangement allows you to avoid the negative influence of weather factors on the performance of the EUR, thereby significantly increasing its service life.

The presence of electric power steering in the car guarantees significant savings in the fuel mixture. Gasoline is spent less because the power steering is turned on only when the steering wheel is turned, unlike the power steering, which operates continuously throughout the entire trip. At the same time, the electromechanical system does not take away a percentage of the power from the motor because is powered by the vehicle's on-board network.

The steering wheel in a car with an electric steering system can be in the extreme position for an unlimited amount of time.

When driving at high speeds, a car with electronic power steering listens well to the driver, so it always remains maneuverable. At the same time, the driving process becomes safer.

Negative qualities of the EUR.

The most significant disadvantage of the electric amplifier is its high price.

The second disadvantage is that the electric motor of the electromechanical system has an insignificant power reserve. For this reason, the ESD is not yet installed on heavy vehicles, but device manufacturers assure that this drawback will be eliminated in the very near future.

A person is forced to exert muscular effort, overcoming the resistance of the wheels when turning the car. There is a need to use an auxiliary device. His invention was an important technical achievement that influenced the further development of the automotive industry.

In the 1920-1930s, they tried to install power steering on heavy dump trucks and armored cars. At first, the devices were pneumatic (using air pressure). The low accuracy of such devices (with increased weight and new speed characteristics of the equipment) opened the way to the use of special hydraulic amplifiers, which have already been tested in shipping. Mass installation of car power steering began in America in the 1940s and spread to post-war Europe. (In the USSR, many production passenger cars were produced without power steering.)

The turn of the 20th-21st centuries marked the beginning of the era of the introduction of electric power steering.

According to statistics, about 10% of Russian drivers prefer a car that is not equipped with power steering. For some of them, the money issue is relevant (or they are owners of small cars).

Some people like the direct feeling of the road, especially at high speeds, and note increased information content on difficult surfaces (ice, wet asphalt). There are motorists who like to make an effort. Most often it is a matter of skill and habit.

Pros and cons of hydraulic power steering.

Pros.

Driving a car equipped with power steering is equally comfortable at all speeds.
The production of power steering is less expensive, so vehicles on which it is installed are noticeably cheaper than their counterparts with electric power steering.
The entire power steering system is quite powerful, so it can easily withstand any load, which means it can be installed on both SUVs and trucks.

Minuses.

Dependence on the engine and constant waste of part of its power, even during high-speed straight-line driving along the highway, when the need to increase the effort applied to the steering wheel is minimal.
Power steering requires careful operation. For example, it is forbidden to hold the steering wheel in the extreme position for more than 5 seconds, as this can cause overheating of the oil in the power steering system and failure of the latter. It is important to always monitor the oil level in the system, replace it twice a year, etc.
Longer response to driver actions than the electric power steering.
Bulky.

Benefits of driving with power steering

the amplifier takes the lion's share of the load onto itself;
there is no need for a large number of turns of the steering wheel, it does not break out of your hands;
the feeling of road unevenness is softened;
the machine is easier to control, maneuverability increases; difficult turns can be made without effort;
taxiing at low speeds becomes more convenient;
the trajectory of movement is stabilized;
if the front tire is punctured, it is easier to hold the car;
the driver is less stressed and does not get tired;
This is especially true if the driver is a woman;
The wear resistance of the steering mechanism increases and its service life is extended.

All this ensures the most safe and comfortable driving (provided the car is in good technical condition).

A potential danger arises only in an emergency situation - a sudden failure (breakdown) of the power steering system when turning while driving. In this case, the reaction, knowledge and experience of the driver become crucial. Problems can be signaled by extraneous noises, vibrations, sharp jolts, turning the steering wheel, turning it difficult or too easy.

According to statistics, a quarter of Russian drivers prefer power steering, and half prefer electric power steering (and the indicators are biased in favor of electric power steering). The advantages of each of these mechanisms are determined by their design features.

Modern cars use electric power steering, hydraulic power steering and electric power steering.

What is power steering in a car (hydraulic power steering)

This device works like a pump. The steering mechanism is influenced by fluid (oil) pressure.

When the engine is turned on, the rotating drive belt drives the hydraulic pump. A constant supply of oil from the tank to the system is maintained.

When the driver turns the steering wheel, a special mechanism (spool valve) moves in response to this rotation and closes the oil drain channel back into the tank. The liquid flows through the distributor (valve) into the power hydraulic cylinder.

It converts fluid pressure into piston pressure, which produces a force on the steering. When you complete a turn and move straight ahead, all channels open, the oil goes back into the tank and continues to circulate idle through the system through connecting hoses.

Power steering

The force applied by the driver to the steering wheel is amplified due to the pressure of the hydraulic fluid in one of the parts of the rack. When the steering wheel is turned, the distributor moves, separating the two parts of the rack (left and right), the fluid pressure in the cavity increases, thereby increasing the driver’s effort applied to the steering wheel.

The pump supplying hydraulic fluid receives torque from the crankshaft using a belt drive. When a car hits an obstacle, the hydraulic fluid prevents the wheel from turning, as it is always under pressure created by the pump.

Comparative characteristics

Disadvantages of electric power steering and advantages of power steering:

There is sensitivity of the EUR to bad (sloppy, bumpy) roads and moisture (in particular, in bad weather - when there is snow, rain, puddles). In such cases, there is a danger of overheating and shutdown, as well as burnout.
The power steering better smooths out shocks when the road is uneven and when hitting a curb.
The EUR does not provide an immediate response if the wheels quickly turn in the other direction. And if you twist the steering wheel sharply, the system may turn off altogether.
There are more possibilities for self-repair for power steering.
In the case of electric power steering, the possibility of electronic failure cannot be ruled out (however, this mainly occurs in old and cheap models; another reason is non-compliance with operating rules).
Production of power steering is less expensive; their price is lower than that of the EUR.
The EUR is limited for installation on heavy trucks and SUVs (due to lack of power).

Advantages of electric power steering

Ease of steering with electric steering (“one finger”). Excellent maneuverability when parking, quick adaptation to changes in speed.
Settings of power steering parameters for various operating modes. (Crosswind stabilization, car parking)
Width of temperature range for EUR. The fluid in the power steering can freeze and boil under the influence of temperatures and overloads.
Simplicity of design and maintenance of the EUR. You just need to monitor the condition of the bearings. Power steering maintenance is more labor-intensive. Regular inspection is required for integrity, monitoring the tightness of hydraulic tubes, checking the tension of the drive belt, and the oil level. There are rules for changing the oil and filter.
Compact dimensions of the EUR.
Economical efficiency of electric power steering (less fuel consumption, higher efficiency).
Operation of the machine after disconnecting the faulty power steering. This is undesirable for power steering (the steering is destroyed; other breakdowns may occur).
The ability to hold the steering wheel in the extreme position for a long time with ESD. On cars with power steering, a delay of more than 5 seconds threatens serious damage.
Environmental friendliness of the EUR. Cars with power steering produce more harmful emissions; power steering units that have expired are more difficult to dispose of.
Serious prospects for progress of ESD.

Differences from power steering

The advantages of electric power steering in comparison with hydraulic power steering (power steering) are:

Simplicity of design and maintenance. Power steering, unlike electric power steering, requires constant monitoring of the fluid level and pump maintenance.
Compact mechanism. The EUR is installed on the steering shaft and does not require additional space under the hood of the car.
Economical. The power steering electric motor turns on only when the steering wheel is rotated, while the power steering pump works constantly, creating additional load on the engine, thereby increasing fuel consumption.
Easy to set up. Only by changing the ECU program is it possible to achieve different operating modes under different circumstances, such as reducing the compensation force when the vehicle speed increases. In the case of power steering, this will require additional active elements in the design.

Disadvantages of electric power steering compared to power steering:

Low (lower) power due to the power of the electric generator. The EUR is installed only on light cars; insufficient power will not allow it to be used on heavy SUVs or trucks without fear of the load on the vehicle's on-board network and the amplifier electric motor. At the same time, the ESD consumes a relatively high current from the on-board network, creating a significant load: for example, the ESD of the Suzuki Wagon R shown above can consume up to 30 Amperes from the on-board network, which is 40% of the generator power (the indicated current is the maximum, at when the car is stationary, when driving less, and after 60 km/h the ESD turns off completely to avoid excessive controllability).

During heavy operating conditions, for example, when driving for a long time on a muddy dirt road, the electric power steering motor overheats. To prevent its failure, the control unit begins to limit the maximum current, accordingly the steering wheel becomes “heavier”, and ultimately turns off completely. To restore normal operation, it is necessary to stop the car for a while in order to cool the electric motor windings, after which operation will be restored.

Disadvantages inherent in both electric steering and power steering, in comparison with steering without power steering:

Danger when driving if both types of power steering fail (the driver's response may not be sufficient to promptly detect a failure of the power steering system if this occurs while the vehicle is turning).