Switched reluctance motors srm have inherent advantages such as simple structure with non winding construction in rotor side, fail safe. Reluctance motor technical seminar report annual year 2014, electrical and electronics department, sdmt, ujire574240 page 4 chapter 2 switched reluctance motor 2. The solenoid has n turns, and when it is excited with a current i the coil sets up a flux increasing the excitation current will make the armature move. If smooth rotation is the goal, there is an electronicdriven version of the switched reluctance motor. For their operation the excitation unit which is controlled in accordance with. Switched reluctance motors srm have been used for years in niche applicationssuch as inside nuclear reactor cores or mineswhere reliability is key. In switched reluctance motor applications both energy and cost efficiency play integral roles. Switched reluctance motor srm the switched reluctance motor srm is a type of motor doubly salient with phase coils mounted around diametrically opposite stator poles. Characteristics and work principles of switched reluctance. Due to variable air gap between stator and rotor, when rotor rotates. The torque production in switched reluctance motor. The stator winding is comprised of a set of coils, each of which is wound on one pole. It describes the comparison results and the performance.
The construction of a 3phase vr stepper motor with 6 poles on the stator and 4pole on the rotor as shown. Switched reluctance motors srm have inherent advantages such as simple structure with non winding construction in rotor side, fail safe because of its characteristic which has a high tolerances, robustness, low cost with no permanent magnet in the structure, and possible operation in high temperatures or in intense temperature variations. In 2014 presented the study on determination of a unique of. Studying different types of power converters fed switched. The reluctance motor is a type of synchronous machine. Switched reluctance motors srm have inherent advantages such as simple structure with non winding construction in rotor side, fail safe because of its. The rotor of a reluctance motor is a squirrel cage with some rotor teeth removed in the certain places to provide the desired number of. This greatly simplifies mechanical design as power does not have to be delivered to a moving part, but it complicates the electrical design as some sort of switching. Pdf 64 switched reluctance motor modeling using matlab.
The reluctance motor has basically two main parts called stator and rotor. Switched reluctance motor srm is gaining much interest in industrial applications such as wind energy systems and electric vehicles due to its simple and rugged construction, high. The companys patented and awardwinning system has been tested in labs and the field and found to boost efficiencyreducing hvac energy use by up to 50% when compared to. This motor works on the principle of variable reluctance. Because they require a power electronic converter and controller to function, however, successful realization of an. Top quality motor control and motor drive solutions from infineons wide portfolio are the ideal choice. These converters are rdump, cdump, cdump with freewheeling transistor, asymmetric, series, and parallel type. A reluctance motor is a type of electric motor that induces nonpermanent magnetic poles on the ferromagnetic rotor. The switched reluctance motor srm is a type of stepper motor, an electric motor that runs by reluctance torque.
Development strategy of rao ues russia main purposes and stages of the project. The switched reluctance motor srm represents one of the oldest electric motor designs around. Switched reluctance motor for electrical drives offor. Hence, three neurofuzzy control strategies for torque ripple minimisation in switched reluctance motors are developed. Constructional features principle of operation variable. Torque is generated through the phenomenon of magnetic reluctance. The vr stepper motor characterized by the fact there is no permanent magnet either on the rotor or the stator. Switched reluctance motors srm are seeing a resurgence as motor manufacturers improve their performance, reliability, efficiency, and cost as. Unlike common brushed dc motor types, power is delivered to windings in the stator case rather than the rotor. Pdf design of switched reluctance motor with exterior. The force tends to align the specimen of the material in such a. We know about different types of synchronous motors, apart from all these motor works based on reluctance. Switchedreluctance sr motor concept has been known since 1838.
Switched reluctance motor srm is an energy efficient machine which receives electrical energy from the power source and returns part of stored magnetic energy back to the supply, during each. Reluctance motor a single phase synchronous reluctance motor is basically the same as the single cage type induction motor. Speed control of 86 switched reluctance motor with. Their structure is similar to that of stepper motors, but switched reluctance motors have fewer magnetic poles. The drive waveform is composed of one or more harmonics to be used to match the reluctance pattern of the statorrotor, causing the rotor to rotate due to the reluctance effect, and one or more other harmonics to induce current in the rotor, causing the rotor. More the air gap, more is the reluctance and viceversa. Switched reluctance generators in contrast to wellknown conventional generators switched reluctance generator srg have toothed stator and rotor, and have neither windings nor permanent magnets in the rotor. Switched reluctance motor srm is also known as variable reluctance motor. When you use these presets, you do not need to specify the parameters in the. As such, research has blossomed during the last decade, and the srm and variable drive systems using srms are receiving considerable attention from industry.
Electrical drives structure of electric power plants. A variable reluctance motor intended to move in discrete steps, stop, and start is a variable reluctance stepper motor. It generates torque through magnetic reluctance reluctance motor subtypes include synchronous, variable, switched and variable stepping. The stator poles have concentrated winding rather than sinusoidal winding. The paper also introduced why the asymmetric bridge converter type is the best one especially for high speeds. Commutating switched reluctance motors with pmac 3 phase referencing as a synchronous motor, the phase position information for an sr motor must have an absolute reference. A stepping motor is a special case of a variable reluctance motor or a permanent magnet brushless dc motor.
It has wound field coils of a dc motor for its stator windings and has no coils or magnets on its rotor. The simulation results are made by matlabsimulink package. Charged evs a closer look at switched reluctance motors. Switched reluctance motors are mainly used in traction, industrial and automotive pumps and home appliances vacuum cleaners and certain washing machines. The stepper motor which includes some of the features of the modern switched reluctance motor was invented and patented in the 1920s in aberdeen by c. The switched reluctance motor srm has both salient pole stator and rotor, like variable stepper motor, but they are designed for different applications, and therefore, with different performance requirements. The hrsr motor is purportedly more efficient than induction motors for all motor speeds and is inherently variable speed.
Smcs switched reluctance motor is changing the game. Evaluation of high rotor pole switched reluctance motors. International journal of information and electronics engineering, vol. Srms are the most reliable electric motors because they eliminate most potential failure modes of motors such as magnets, overlapping coils that can short, and rotor currents, morris says. This paper presents the design procedure for three phase switched reluctance motor srm with two different cases case1. A variation on the conventional reluctance machine has been developed and is known as the switched reluctance sr machine. Since there is only a single excitation source and because of magnetic saturation, the power density of reluctance motor is lower than pm motor. Variable reluctance motors or steppers actually use rotors like those in figure below. Walker a stepping motor is a special case of a variable reluctance motor or a permanent magnet brushless dc motor. Switched reluctance motor srm controller and driver. A stepper motor is designed to make it suitable for open loop position and speed control in low power applications, where efficiency is. Torque per unit volume equations are obtained for each of the motor, related to quantities such as magnetic flux density and electric loading and the speed performances are. As the name suggests, a switching inverter is required for the operation of. The stator of the motor has the main and auxiliary winding.
But the lack of semiconductors to rapidly switch current on and off and a limited supply of engineers with the technical knowledge. A stepper motor is designed to make it suitable for open loop position and. The sr motor produces torque through the magnetic attraction which occurs between stator electromagnets and a corresponding set of salient poles formed on a simple rotor made only of ferromagnetic material. There are no windings or permanent magnets on the rotor. Simulation and testing of a switched reluctance motor by.
The goal of this project was to evaluate a high rotor pole switched reluctance hrsr motor system for use as a condenser fan motor for commercial refrigeration systems. Switched reluctance motors the structure of a switched reluctance motor is shown below. Model the dynamics of switched reluctance motor simulink. Construction details of switched reluctance motor with six stator poles and four rotor poles can be explained by referring to figure 3. Electric drives brushless dc ac and reluctance motors. This does not mean that an absolute position sensor must be used.
Unlike a conventional synchronous motor, both the rotor. Us7852037b2 induction and switched reluctance motor. The switched reluctance machine srm is the least expensive electrical machine to produce, yet one of the most reliable. This means, the rotor always tries to align along the lowest reluctance path. This application describes a motor designed to operate as a reluctance machine at low speeds and as an induction machine at high speeds. Switched reluctance motor aims to disrupt the market. Motor the torque production in the switched reluctance motor is explained using the elementary principle of electromechanical energy conversion in a solenoid, as shown in figure 2. Switched reluctance motor concept, control and applications.
Characteristics and work principles of switched reluctance sr motor photo credit. Srm are made up of laminated stator and rotor cores with ns2mq poles on the stator. Design of linear switched reluctance motor driver for. Switched reluctance motor modes of operation converter. Switched reluctance motor for electrical drives offor electrical drives electric power plants equipment vladimir kuzmichev mpeitu, orgres. You benefit from proven reliability and excellent figures of merit along with. Switched reluctance motor drives are one of the most promising alternatives of ac induction and permanent magnet synchronous motor drives. Switched reluctance motor aims to disrupt the market 27 february, 2018 a californian company has developed a new form of highefficiency switched reluctance motor which, it claims, will dramatically improve the performance of hvac, refrigeration, pumping and other applications. Here we will discuss construction and working principle of reluctance motor. With continued research, different topologies have emerged presenting less torque ripple, high efficiency, high. The operation of reluctance motor with diagram reluctance motor. Simulation and testing of a switched reluctance motor by matlab simulink and dspace master of science thesis in electric power engineering saman abbasian department of energy and environment faculty of electric power engineering chalmers university.
Reluctance motors can deliver high power density at low cost, making them attractive for many. The rotor is basically a piece of laminated steel and its shape forms salient poles. The rotor is created from lamination in order to minimize the eddycurrent losses. Isbn 97895352677, eisbn 97895352684, pdf isbn 9789535147848, published 20170621. Pdf switched reluctance motor drives devendra tandel. This paper presents speed control of switched reluctance motor srm with torque ripple reduction using direct instantaneous torque control ditc. Motor runs at slip speed reluctance torque, trel reluctance torque, trel maximum reluctance torque, trelmax occurs at.