It generates torque through magnetic reluctance reluctance motor subtypes include synchronous, variable, switched and variable stepping. Mathematical analysis consider an elementary reluctance motor as shown in the fig. The resistance of the rotor must be very small and the combined inertia of the rotor and the load should be small to run the motor as a synchronous motor. The purpose of this master thesis is therefore to design a high efficiency synchronous reluctance.
A reluctance motor is a type of electric motor that induces nonpermanent magnetic poles on the ferromagnetic rotor. The stator of the single phase reluctance and induction motor are same. The subtypes of reluctance motors include synchronous reluctance motors and. This motor is called a pm assisted reluctance synchronous motor. To understand the working of synchronous motor, let the stator of the synchronous motor be wound for two poles. We will look into the construction details of the various parts one by one in detail. Design of synchronous reluctance motor for hybrid electric. Rotor design of linestart synchronous reluctance motor to. Aim and scope of the project the aim of the project is to design a real synchronous switched reluctance motor and analyze how the key parameters, some of which are great indicators of the good performance of the motor. The structure of reluctance motor is same as that of salient pole synchronous machine as shown in fig. Construction of a synchronous motor is similar to an alternator ac generator. Just like any other motor, the synchronous motor also has a stator and a rotor.
The rotor has neither windings nor permanent magnets. Design and performance of high efficiency synchronous. Reluctance motor subtypes include synchronous, variable, switched and variable stepping. Finite element analysis is performed for the reference induction motors initially. To achieve this a suitable theoretical model is essential, thus a simple but complete motor model is developed. Reluctance motors can deliver high power density at low cost, making them. Characteristic analysis of permanent magnetassisted synchronous. The synchronous reluctance sr motors driven by variable speed inverters have been recently introduced in the industrial market. Thus finally the reluctance motor runs as a synchronous motor. Jun 16, 2016 basically the synchronous reluctance motor is a true ac rotating field machine, requiring a balanced polyphase sinusoidal supply into a distributed winding, which for all intents and purposes is identical to that of the induction machine of the same power rating. Construction and principles of operation the slosyn motor is unique in that it has the capability of being operated as an ac synchronous, constant speed motor or as a phase switched dc stepper motor. It generates torque on the principle, that any unmagnetised magnetic material will try to align itself along the path of least magnetic reluctance path. Jul 25, 2018 the secrets behind the technology abb synchronous reluctance motor drive packages duration. With continued research, different topologies have emerged presenting less torque ripple, high efficiency, high.
Synchronous machines 2 in this chapter, we concentrate on conventional synchronous machines whereas the brushless dc motors will be discussed later in a separate chapter. Aircraft electric general electric motor design and construction discussion switched reluctance motor srm synchronous reluctance motor synrm thread tools nov 06, 2016, 08. Synchronous reluctance motor for household applications. A variation on the conventional reluctance machine has been developed and is known as the switched reluctance sr machine. The structure of the motor and specifically the structure of its rotor are analyzed, while the basic operating principles are presented and references on commonly used control. Where, n s synchronous speed, f supply frequency and p number of poles. Ie5 synchronous reluctance motors, 9akk107743 en 122019 english pdf catalogue product note. Rotor design of linestart synchronous reluctance motor to improve starting performance seunghyoung ha1, jungpyo hong1, jiyoung lee1, hyuk nam2, gyuhong kang3 dept. Of synchronous machines the synchronous electrical generator also called alternator belongs to the family of electric rotating machines.
Reluctance motor a single phase synchronous reluctance motor is basically the same as the single cage type induction motor. Working of synchronous motor your electrical guide. The lowspeed torque capability is compared with that of an induction motor, a switched reluctance motor, and a brushless dc pm motor of identical size and copper weight. The diagram shows the motor construction with a single polepair on the rotor. The synchronous speed is the constant speed at which motor generates the electromotive force. To save computation time, rather than calculating the ac losses for each simulation in the optimization, i solved for the losses in a simplified geometry a simple tube with 50 mm od, and 42 mm id, the same dimensions as the stator back iron over the entire space of frequencies and. Whats the difference between asynchronous and synchronous. Synchronous reluctance motordrive package for industrial use. Analytical calculation of magnetic field components in synchronous. Design and effective operation of double winding synchronous. Unlike an induction rotor, which requires a cast, bar, or wound squirrel cage, or a permanent magnet bldc motor, which requires bonding magnets to the rotor, a reluctance motor requires a simple steelonly rotor. If load is excessive motor may not pull into synchronism and if already running it may pull out of synchronism. Ie4 synrm motor and drive package induction motor on the outside, innovation inside synchronous reluctance motors combine innovative rotor and conventional stator technology. In terms of efficiency and power density, synchronous reluctance motors synrms represent a major step forward in sustainable electric motor technology.
Optimum design parameters for synchronous reluctance motors j. The influence of the major parameters on the motor performance has been theoretically determined. Hi friends, in this article, i am going to discuss the construction and working of synchronous motor. A technological and smart solution for ever increasing demand for high efficiency and cost reduction. Synchronous reluctance motordrive package for machine. Synchronous reluctance motor ideal for pumphydraulic applications. Both motor types use the same stator, but have different rotors. Both the motors have similar torque speed characteristics, similar construction except rotor and work on the same. The paper deals with the design of a synchronous reluctance motor suited for hybrid electric vehicles. The synchronous motor would run at synchronous speed, once synchronized, irrespective of variation in supply voltage or load. Despite many efforts being devoted to simplify the analysis of synchronous reluctance motors synrm, the use of analytical methods to calculate torque ripple. We know about different types of synchronous motors, apart from all these motor works based on reluctance.
The variable reluctance motor is based on the principle that an unrestrained piece of iron will move to complete a magnetic flux path with minimum reluctance, the magnetic analog of electrical resistance synchronous reluctance. Synchronous motor is one of the most efficient motors. A stepper motor is designed to make it suitable for open loop position and. They are capable to achieve very high efficiency level and to gain the maximum efficiency class ie4 of iec 6003430 standard. The construction of a synchronous motor is very similar to the construction of an alternator. To calculate eddy current and hysteresis loss in the stator, i used the built in harmonic ac solver in femm 4. The block supports a second rotor axis definition for which rotor mechanical angle is defined as the angle between the aphase magnetic axis and the. As we can see from the equation, the synchronous speed depends on the frequency of the supply and the number of poles. Here, the rotor turns at the same rate that is, in synchronization as the stators magnetic field. To save computation time, rather than calculating the ac losses for each simulation in the optimization, i solved for the losses in a simplified geometry a simple tube with 50 mm od, and 42 mm id, the same dimensions as the stator back iron over the entire space of. Other members of the family are the directcurrent dc motor or generator, the induction motor or generator, and a number of derivatives of all these three. Simulation is key to design of highefficiency, lowcost.
The synchronous reluctance motor magnetic reluctance is the magnetic. Depending upon the type of reluctance motor, the construction of these two parts. Up to 94% efficiency, much more efficient than acim alternate current induction motor machine in all speed. Instead, the magnetic principle of reluctance is utilized. Construction of synchronous reluctance motor brainkart.
Looking back to the history to jump ahead in the future. A synrm rotor has neither a conducting short circuit cage as with the im, nor permanent magnets, nor a field excitation winding. Future of wood drying, synchronous reluctance synrm motors in wood drying applications english, finnish pdf leaflet. The aim of this study is to design and compare synchronous reluctance motors, which can be alternative to the reference induction motors. Permanent magnet synchronous reluctance motor design. Sometimes it may also be called the ipm reluctance synchronous motor. Optimum design parameters for synchronous reluctance motors. Reluctance motors can deliver high power density at low cost, making them attractive for many. Here we will discuss construction and working principle of reluctance motor. In either case, it is classified as a permanent magnet inductor motor. The synchronous motor is used for converting the electrical energy into mechanical energy. The laminations reduce the eddy current loss occurs on the winding of the transformer.
Comparisons are given with inductance and torque characteristics of normal synchronous reluctance motor synrm and those according to quantity of residual. Synchronous reluctance motorconstruction, working principle. 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. Synchronous reluctance motordrive package for industrial. You get the performance of a permanent magnet motor together with the costefficiency, simplicity and servicefriendliness of an induction motor. Due to the wide use of electric motors in the world take into account that. Due to the complex rotor geometry in the synrm, a suitable and simple combined. The basic features of this motor with regard to the other types of motors are shown. Thermal analysis of induction and synchronous reluctance.
In this study, the synchronous reluctance motor family is compared at three different power levels. Synchronous reluctance motor intoduction concepts youtube. Oct 26, 2012 the threephase synchronous reluctance motor synrm is presented as a possible alternative in allelectric ship applications. The rotor of the synchronous motor is made with the laminations of the steel. Switched reluctance and synchronousreluctance motors are both synchronous designs.
This post will discuss synchronous motor, its construction, working principle, types, characteristics, starting methods, applications, model phasor diagram, advantages and disadvantages. Synchronous reluctance technology combines the performance of the permanent magnet motor with the simplicity and servicefriendliness of an induction motor. A synchronous motor has a special rotor construction that lets it rotate at the same speed that is, in synchronization with the stator field. The synchronous reluctance motor synrm has been studied. A reluctance motor torque is produced due to the tendency of the rotor to align itself in the minimum reluctance position, when the speed of the motor is close to the synchronous speed. The stator poles have concentrated winding rather than sinusoidal winding.
The simple salientpole construction is very robust and as such suitable for spindle drives. Unit 1 synchronous reluctance motors constructional. Synchronous motor an overview sciencedirect topics. Switched reluctance motors the structure of a switched reluctance motor is shown below. The reluctance motor has basically two main parts called stator and rotor. Up to 94% efficiency, much more efficient than acim alternate current induction motormachine in all speed. The operation of reluctance motor with diagram a media to. The stator windings also connect to the ac power as in an induction motor.
The rotor of a reluctance motor is a squirrel cage with some rotor teeth removed in the certain places to provide the. The rotor has neither magnets nor windings and suffers virtually no power losses. A same synchronous machine can be used as a synchronous motor or as an alternator. Synchronous reluctance machine design 1 1 introduction the purpose of this report is to present information necessary for developing a suitable synchronous reluctance motor synrm rotor geometry design procedure.
Basically the synchronous reluctance motor is a true ac rotating field machine, requiring a balanced polyphase sinusoidal supply into a distributed winding, which for all intents and purposes is identical to that of the induction machine of the same power rating. The variable reluctance motor is based on the principle that an unrestrained piece of iron will move to complete a magnetic flux path with minimum reluctance, the magnetic analog of electrical resistance. A reluctance motor is a type of synchronous electric motor. It is usually assumed that windings of pmsrm are ributed sinusoidally. Both are synchronous machines where one we use as a motor and the other as a generator. Permanent magnet assisted synchronous reluctance motor design and performance improvement. Essential parts of the synchronous motor are the same as those of the synchronous generator i. The main feature of a segmented type synchronous reluctance motor is the flux barrier. Like the induction motor, the synchronous ac motor also contains a stator and a rotor. Insidepenton com electronic design adobe pdf logo tiny.
The advantages of the synchronous reluctance motor ee. Synchronous motor construction is very similar to that of a synchronous generator. The design and principle of operation of the synchronous. The d, q inductance difference and saliency ratio are identified as they are related to torque and power factor 2. Synchronous motors are available in a wide range, generally rated between 150kw to 15mw with speeds. Both are synchronous machines where one we use as a motor. Optimum design parameters for synchronous reluctance. In particular an useful approach is proposed to choose the proper angles of the fluxbarrier ends with the aim of reducing the torque ripple due to the slot harmonics. Mar 19, 2018 the construction of a synchronous motor is very similar to the construction of an alternator. The design of the double winding synchronous reluctance motor is affected by various constraints such as thermal limit, overload capacity.
Sr motor principle and related torque general equation. The synchronous motor working principle is based on the principle of magnetic locking between stator and rotor poles. Based on the space vector diagram we alter the torque expressions. The ability to control their power factor makes it very demandable especially for low speed drives. Synchronous reluctance motors process performance motors. Synchronous reluctance machine with sinusoidal flux. The word salient means the poles of the rotor projected towards the armature windings.
The operation of the synchronous induction motor is explored in this video. Analytical design of a synchronous reluctance motor srm. Figure 1, shows the diagram of a simple reluctance motor, where the entire magnetic. Although introduced over a century ago, electric motors continue to experience bursts of innovation and recent years have seen remarkable progress in electric motor efficiency improvements. In order to understand the working principle of such motor, you should realize that the sr rotor has neither a conducting short circuit cageas the.
Design of synchronous reluctance motor for hybrid electric vehicles conference paper pdf available in ieee transactions on industry applications 514. Pdf amidst increasing need to utilize electrical machines efficiently for the. Synchronous machine structures stator and rotor the armature winding of a conventional synchronous machine is almost invariably on the stator and is usually a three phase winding. Synchronous motor and induction motor are the most widely used types of ac motor.
Pdf efficiency analysis of synchronous reluctance motors. Synchronous reluctance motors are increasingly being used in a wide range of industrial applications because of their unique combination of high efficiency, high power density and low manufacturing costs. Let the rotor also produces two poles when they are excited by the external dc source. All about reluctance motors what they are and how they work. Analytical design of a synchronous reluctance motor srm pag. Switched reluctance motor srm synchronous reluctance. This is a 4phase machine with 4 stator pole pairs and 3 rotorpole pairs 86 motor. Sep 29, 2015 the synchronous reluctance motor synrm has been studied.
If the rotating field of a large synchronous motor with salient poles is deenergized, it will still develop 10 or 15% of synchronous torque. Synchronous reluctance motor electric motor rotating machines. Rather than using a traditional 3phase configuration, i was interested in investigating a highphase order machine with each stator slot corresponding to an individually controlled phase. The stator has 30 slots, so each coil has a 180 degree pitch. The load inertia should be within the limits, for proper effectiveness.
The stator of the motor has the main and auxiliary winding. A singlephase linestart synchronous reluctance motor lssynrm has both conductor bars and flux barriers in the rotor. The switched reluctance motor srm represents one of the oldest electric motor designs around. Synchronous reluctance motor the stator windings are identical windings and displaced 120 from each other with ns equivalent turns and resistance of r s. A reluctance motor has some very key advantages, particularly regarding the construction of the rotor. Jun 11, 2017 the operation of the synchronous induction motor is explored in this video. Synchronous reluctance machine synrm design electrical. Pdf design of synchronous reluctance motor for hybrid. A segmentalrotor synchronous reluctance motor is used in a variablespeed drive with currentregulated pulsewidthmodulated pwm control. Ee6703 unit 1 synchronous reluctance motors 1 prepared by. Synchronous motors controlled by variablespeed drives are. Design of a synchronous reluctance motor assisted with. In transient state from start to reach synchronous speed, the motor characteristics are determined by conductor bars, and the characteristic profile has an irregular form as shown in fig.