In almost all modern vehicles, electric power steering is in use. Pdf control of an electric power assisted steering system using. Sumit thakur mechanical power steering ppt presentation pdf report. The inputs to the pmsm controller are the angular difference from one end of the steering column to the other and the. Speed sensitive steering there is more assistance at lower speeds and less at higher speeds. Power steering system in automobiles presented by vishal v. Power assisted outboard steering system ultraflex group. Download seminar report for electric power assisted steering.
This means that there is a problem since the forces in the case of a retracting piston are lower than when the piston extends. These distinct types are explained in below diagram. Power steering electronic power steering system ps7 ps 2 when reconnecting a connector related to the electric power steering system, ensure that the power switch is off. Also hybrid hydraulicelectric systems were developed. Rahman encyclopedia of life support systems eolss figure 2. A power assisted steering system of the type which includes a hydraulic reaction mechanism for controlling the hydraulic power assist in accordance with an increase or decrease of the vehicle speed. Power steering is a system that helps in steering the wheels using some source of power. Electro hydraulic power steering ehps is an advanced system that uses c onventional hydraulic power steering with an electric motor.
Power steering systems supplement the torque that the driver applies to the steering wheel. Hydraulic power steering system design in roadanalysis. The system includes primary and secondary hydraulic pumps, the primary pump having the function of applying hydraulic pressure to the power cylinder and the secondary pump having the function of. The eps system is gradually replacing the hydraulic steering system and is likely to.
From the configuration of the powerassisted steering system, we can see that the power assistance is performed by a differential cylinder. Therefore power steering or rather powerassisted steering was introduced to assist the driver. All air must be removed, or fluid in pump may foam during operation and be discharged from pump reservoir. At this point, the fluid pressure in chamber a of the power cylinder increases depending on the.
Power steering system must be filled exactly as explained in the following to ensure that all air is bled from the system. Distinct types of steering systems power assisted hydraulic steering systems. Check a powersteering system at least twice a year more often if recommended by the car handbook, or if the steering becomes heavy or jerky. Pdf control of electric power assisted steering system using. Masterdrive system features eliminates torque at the steering wheel. Electric power assisted steering eps uses an electric motor to provide directional control to the driver, without any hydraulic. The main difference between the different types of pumps is the design of the fins that. Innovations drivers for electronic power assisted steering system. Manual steering is totally different type of steering in. The driver uses the steering to control the course taken by wheels. Converter, torque control, rack and pinion, torque assist map, steering angle.
Replacing hydraulic assist with a computercontrolled electric motor seemed like a. Effortless steering for the most demanding applications. Traditional power steering systems are hydraulic systems, but electric power steering eps is becoming much more common. Advantages of the ephs electrically powered hydraulic steering when driving solely on motorways, there is a high power loss at the bypass valve in a conventional powerassisted steering system as a result of the high engine speed, in other words at low steering angle rates and high engine speed, the power steering pump supplies an excess. This example shows how to use a permanent magnet synchronous motor pmsm to amplify driverapplied force in a powerassisted automobile steering system. On an io installation, the pump is attached to the engine block and turned by a pulley, just like the power steering pump on an automobile. How electric power assisted steering works, and why its. Electro hydraulic power steering ep as systems electric. If youve ever tried to turn the steering wheel of a car with no power steering while stopped or barely moving, you will notice how much force is required. Power steering gives a feedback of forces acting on the front wheel to give a sense of how wheels are interacting with the road. System, brushed dc motor, permanent magnet ac synchronous motor, power. Eps also enables adas features, such as lane keeping, park assist, active return to center, traffic jam assist and much more. Electric power assisted steering has temped automotive engineer since the 1950.
Different types of power steering pumps are used to power the system. Remote reservoir on powerassisted rack and pinion steering system. Electric powerassisted steering with suspension nada. The electric motor has an output shaft offset from the steering shaft. Iii electric power assisted steering system for automobiles m. Power assisted system power steering power steering system ps10 when steering force is applied. First, a reference model is employed to generate ideal motor. Power assisted inboard steering systems features and working principle 4546 power assisted inboard cylinders 4749 power assisted electrohydraulic power units 50 power assisted steering system applications and systems 5155 power assisted steering system. Any information used by the steering car speed, alternator, city, steering effort can be varied by the user. The difference between power steering and power assisted. Sensorless control of electric power assisted steering system.
Foamy fluid also may cause power steering system to become spongy, which may result in poor boat control. On outboards, the system in completely selfcontained and uses no external electric motor. This results in power dissipation through the continuous operation of the pump and therefore to a high demand for energy. Principle of the steering system with rackandpinion steering gear without power assistance. Control of an electric power assisted steering system using refer ence model a. A powerassisting structure includes a motor driven member and is mounted on the. This paper presents a new control strategy of electric power assisted steering epas systems to ensure several control objectives. Electric power assisted steering system for automobiles eolss. What is powering the steering system in your vehicle. The steering wheel angular velocity represents the input from the driver.
Diravi is the first commercially available variable power steering system introduced by citroen. A traditional powerassisted steering system uses hydraulic power to assist the driver, referred to as hydraulic power assisted steering hpas. Eps electric power steering new vishay intertechnology. Center the steering wheel and then turn the power switch on ig. The electric powerassisted steering trainer operates with a macpherson suspension to display a modern power steering system.
The main purpose of any type of power steering system is to attenuate the driver effort required to steer the vehicle i. The oil works a piston that helps to push the steering in the appropriate direction. Valves in the steering rack or box open whenever the driver turns the wheel, allowing oil into the cylinder. Steering refers to guiding the wheels towards the intended direction. A doubleacting hydraulic cylinder applies a force to the steering gear, which in turn steers the roadwheels. A conventional hydraulic power assisted steering system, with the necessary additional pumps and fluid reservoirs needed for the system to function. Quantum dots pdf ppt presentation power steering presentation and pdf report these distinct types are explained in below diagram. Internal power steering this system is factory installed on high horsepower outboards and most io installations. Unesco eolss sample chapters electrical engineering vol. Optimal design of electric power assisted steering system epas using gapid method. Pdf control of electric power assisted steering system.
Control of electric power assisted steering system using sliding mode control. Hydraulic power steering systems work by using a hydraulic system to multiply force applied to the steering wheel inputs to the vehicles steered usually front road wheels. The masterdrive power assisted outboard steering system delivers fingertip control regardless of speed or torque conditions. Eps eliminates many hps components such as the pump, hoses, fluid, drive belt, and pulley. Electric powerassisted steering epas is a new power steering. Nexteers electric power steering eps gives you comfort, control and feeloftheroad. This paper deals with the sensorless control of electric powerassisted steering epas system with the permanent magnet synchronous motor pmsm using sliding mode techniques. The assist characteristic of epas is set by control software, which is one of the key. The traditional hydraulic power assisted steering, hpas, system, cannot meet these new demands, due to the control units pure hydromechanical solution. The hydraulic pressure typically comes from a gerotor or rotary vane pump driven by the vehicles engine. When the steering wheel is turned to the right, for example, fluid passages v 1 and v 3 are opened while fluid passages v 2 and v 4 are nearly closed. Control of an electric power assisted steering system. Zhao yan, non conduct steering sensor for electric power steering system international conference of information and automation. Electric power assisted steering electro hydraulic power steering ep as systems the first version of electric power assisted steering was the changing of the power s ource for the traditional hydraulic power steering from a mechanical pump, driven off the engine via a belt drive arrangement to an electr ically driven pump.
The estimator relies on several lectric power assisted steering systems epas are e replacing hydraulic power steering in many new vehi cles today. Power steering utilizes a hydraulic pump running off a beltdriven by the engine, this pump enables a. The active pinion concept presented in this thesis is a novel concept. A powerassisted steering system for an automotive vehicle has a steering shaft rotatably supported by a steering column, a steering wheel and an electric motor for assisting in rotating the steering shaft when the steering torque is too great. Optimal design of electric power assisted steering system. Power assisted hydraulic steering systems which are in use are mentioned below. Remote reservoir on power assisted rack and pinion steering system. The engine drives a pump that supplies oil under high pressure to the rack or the steering box. On a powerassisted steering system, an hydraulic cylinder assists.
Pdf the control of electricpowerassisted steering epas systems is a challenging problem due to multiple objectives and the need for. Power steering gives a feedback of forces acting on the front wheel to give a sense of how wheels. Power steering is the method automotive manufacturers employ to reduce steering effort and reduce rough surface feedback through the steering wheel. A specific advantage of power steering is speed adjustable steering, where the steering is heavily assisted at low speed and lightly assisted at high speed. Electric power steering eps and a matter of torque 2. International journal of engineering and innovative. Thissystemisapurehydromechanicalsystemandlacksthe possibility to be activated other than by driver input. Power steering too much physical exertion was needed for vehicles external power is only used to assist the steering effort. Pudlo abstract this paper presents a new control strategy of electric power assisted steering epas systems to ensure several control objectives. A centrifugal regulator driven by the secondary shaft of the gearbox gives a proportional hydraulic pressure to the speed of the car this pressure acts on a cam directly revolving according to the steering.
Power steering systems date back to 1925 when they were first introduced by the detroit pump manufacturer vickers. At present, there are distinct types of steering systems or mechanisms in use. The video course teaches you everything about modern cars. Pdf electric power assisted steering semantic scholar. Steering column assembly electric powerassisted steering epas steering wheel steering gear intermediate shaft figure 1. Powerassisted steering will allow you to steer your vehicle manually when the engine is not running or if you have a failure in the power steering system which disables it. Though several variations exist due to advancements in. External power is only used to assist the steering effort. Pdf this paper presents a new control strategy of electric power assisted steering epas systems to ensure several control objectives. Pdf a new control strategy of an electricpowerassisted. Electrically assisted power steering eps is the latest technological cross we bear. Pressure control in hydraulic power steering systems. Difference between power steering and manual steering.
Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Keywords eps electronic power steering system, ecu. Hydraulic systems are also a complicated mix of maintenanceintensive and expensive. The benefit of power steering is really ease of operation. Referencesresearch papers1 srihari vijayakumar and ram chandran. Power steering is a synonym for power assisted steering.
Big range 56 steering system for catamarans 57 hydrostatic steering systems with engine. In a rackandpinion system with power assistance, the rack receives the. Do not turn the power switch on ig when the steering wheel is not centered. Electric power steering eps is the another name for epas. Electric power assisted steering system for automobiles.
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