Non salient or cylindrical pole type salient pole type. 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. By the definition, synchronous generators produce electricity. Synchronous generator an overview sciencedirect topics. As the field continues to turn and the north pole starts to move away from the winding, the current decreases as the strength of the field cutting the winding decreases. Difference between salient pole and non salient pole. Dynamic modelling and simulation of salient pole synchronous motor using embedded matlab onah, c. The first method uses optical encoder to detect the rotor position. Non salient pole b stator windings or armature windings the rotor of a synchronous generator is a large electromagnet and the magnetic poles on the rotor can either be salient or non salient construction. Model the dynamics of threephase roundrotor or salientpole synchronous machine. Nov 28, 2012 2 thoughts on design of salient pole synchronous machine omran musa adam june 10, 2014 at 3. There are mainly two types of synchronous generator from rotor construction point of view.
Base values, transformation ratio, and rotor parameters referred to the stator. The shaft and pole bodies are of integral construction, produced from a single normalized carbon steel forging. Cylindrical rotor alternators are usually long, and the problem of air f low. This paper is focused design calculation of 30 mva, 11 kv, 50 hz, two pole non salient poles synchronous generator that use in gas turbine power plant. The choices of specific loadings are magnetic loading and electric loading are involved in that. According to the shape of the field, synchronous machines may be classified as cylindricalrotor nonsalient pole machines and salientpole machines. The slow speed salient pole alternators are ventilated by the fan action of the salient poles which provide circulating air. Ieee guide for synchronous generator modeling practices and. Simulation model for fault on stator winding of salientpole generator. To find xd and xq of a salient pole rotor type synchronous machine by slip test apparatus. Salient pole machine, or effect of salient poles, or two reaction theory 2.
The two coils of the 4 pole generator synchronous machine working principle of fig. Pdf study of salient poles synchronous generator by. The terminal voltage, v t, is taken as the reference phasor. A guide for synchronous generator parameters mafiadoc.
Analysis of salientpole synchronous generators operating in single. Determination of load angle for salientpole synchronous. Pdf compatibility design of non salient pole synchronous. What is the difference between a salient pole and a. Damper windings are provided in the pole faces of salient pole alternators. These type of machines have salient pole or projecting poles with concentrated field windings. Procedure of synchroniation a dark lamp method b synchroscope c computerized synchronisation 6. It has a large number of projecting salient poles, having their cores bolted or dovetailed onto a heavy magnetic wheel of castiron, or steel of good magnetic quality fig. Pdf study of salient poles synchronous generator by finite. However, synchronous generators without multipoles require gearboxes in order to produce the required frequency for grid connection. A system and method to provide an improved power electronics starting system 100 in which starting torque is delivered by a salient pole synchronous machine 102, while associated power electronics 110 and 118 utilization is maximized by adjusting the park vector of the armature 102 a phase current to remain inphase with the park vector of the armature 102 a terminal. Determination of load angle for salientpole synchronous machine. A salient pole synchronous generator, as shown in fig.
In nonsalient pole alternators, air gap length is constant and reactance is also constant. There are some disturbing factors in salient pole alternators which are analysed below. Completeview documentation, software updates, and teamviewer download. The rotor magnetic field induces a voltage in the stator which becomes maximum in. This rotor has solid poles and a striponedge field winding. In this type, salient or projecting poles are mounted on a large circular steel frame which is. Synchronous generator construction, synchronous generator parts, salient pole rotor, smooth cylindrical rotor, brushless excitation system of synchronous generator.
Our synchronous generators are manufactured at the vem dresden locations sachsenwerk. The synchronous electrical generator also called alternator belongs to the family of electric rotating machines. The salient pole generator explores the principles and characteristics of salient pole generators. Power equation derivation of a salient pole synchronous machine. In fact, a given synchronous machine may be used, at least theoretically, as an alternator, when driven mechanically or as a motor, when driven electrically, just as in the case of d. The series connection gives double the voltage of one coil and can handle the. An insideout salient pole core for a dynamoelectric machine.
Model the dynamics of threephase roundrotor or salientpole. Eeeb344 electromechanical devices chapter 5 chapter 5. As is discussed in chapter 4, a single synchronous generator supplying power to an impedance load acts as a voltage source whose. Design of salient pole synchronous machine matlab examples. This type of construction is for the machines which are driven by. A field coil is an electromagnet used to generate a magnetic field in an electromagnetic machine, typically a rotating electrical machine such as a motor or generator. The ends of the damper bars are short circuited at the ends by short circuiting rings similar to end rings as in the case of squirrel cage rotors. Pdf analysis of nonsalient pole synchronous generator using. In general, synchronous generator consists of two parts rotor and stator. Therefore from the literal meaning of saliency one can guess that salient. Salient pole synchronous motor power developed by a salient pole synchronous motor effects of excitation on armature current and power. Introduction most of the electrical power used aboard navy ships and aircraft as well as in civilian applications is ac.
We are quite familiar with synchronous generator or often called alternator. Each field pole of a salient pole rotor has a pole running lengthwise along the cylinder. Multi pole synchronous generators can be used more efficiently since the gear can be eliminated and direct drive of the turbine and generator can be achieved 170, 171. The real output power of the synchronous generator is p v i v i out t l a 3 cos 3 cos the reactive output power of the synchronous generator is q vi viout t l a 3 sin 3 sin recall that the power factor angle is the angle between v and i a and not the angle between e a and i a. The power output of a synchronous generator is the sum of the power due to the directaxis current d and the power due to the quadratureaxis current. Salient pole generators will have large diameter and short axial length pole shoes cover 23 of the pitch salient poles are laminated in order to reduce eddy currents they are used in hydraulic turbines or diesel engines salient pole generators will have typical speed about 100 to 375 rpm. Synchronous generator construction and working principle. This asymmetry can produce vibrations that may affect the units ability to reach full load and can accelerate wear on bearings and other generator components.
Ger4212 ge generator rotor design, operational issues. Turn a ceiling fan into a wind turbine generator duration. Non salient pole rotors are normally used for rotors with 2 or 4 poles rotor, while salient pole rotors are used for 4 or. Due to the uniform air gap, the field flux, as well as armature flux vary sinusoidally in the air gap. In english, salient means sticking out or most noticeable or. Damper windings are nothing but the copper or aluminum bars housed in the slots of the pole faces. We knew that in non salient pole type alternators the air gap is uniform. Our new mediumspeed threephase highvoltage generators in salient pole design are available. The changes are made keeping the original flavor of the book intact, that is, indepth coverage of fundamental concepts. It contains everything needed for salient pole generator experiments including resistive, capacitive and inductive load banks.
Electric machines by dp kothari and ij nagrath now in its 5. The salient pole rotor shown in figure 34, view b, is used in lowspeed alternators. When neither pole is nearest the winding, the current through the winding is zer o. Mediumspeed synchronous generators mediumspeed synchronous generators product overview product overview our new mediumspeed threephase highvoltage generators in salient pole design are available at 900 mm to 1,120 mm shaft height with eight to twelve poles. Determination of x d and x q direct axis and quadrature axis reactances 4. If you could compare the physical size of the two types of rotors with the same electrical. Cylindrical rotor alternators are usually long, and the problem of air f low requires very special attention. In a rotating machine, the field coils are wound on an iron magnetic core which guides the magnetic field lines. This paper presents two methods for load angle determination for salient pole synchronous generator. This two reaction theory was given by professor andre blondel so it is named as blondel two reaction theory. Blondel two reaction theory salient pole alternators theory.
The theory which gives the method of analysis of the disturbing effects caused by salient pole construction is called two reaction theory. Fajoni abstractthis paper shows, through simulations using the software matlabsimulink, its library simpowersystems and the standars ieee 115 1995, ieee 1110 2002, how to perform load rejection tests for salient pole synchronous. Pole of the field moves past the winding, a large current flows through the winding. Difference between cylindrical and salient pole rotor. A guide for synchronous generator parameters determination using dynamic simulations based on ieee standards juan c. Salient and nonsalient pole synchronous generator physics. 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. Construction of synchronous machines in a synchronous generator, a dc current is applied to the rotor winding producing a rotor magnetic field. Sudden short circuit of a synchronous generator, transient and subtransient reactance s. The salient pole rotors are used only by low and medium 120 500 rpm. The open and flexible design is ideal for lecturers to create. Salient pole generator description the salient pole generator explores the principles and characteristics of salient pole generators. The open and flexible design is ideal for lecturers to create their own experiments, as well as student project work.
Mar 04, 2020 there are mainly two types of rotors used in construction of alternator. Improved transient simulation of salientpole synchronous. In salient pole type of rotor consist of large number of projected poles salient poles mounted on a magnetic wheel. Explain the constructional details of alternator in. Model the dynamics of threephase roundrotor or salient. Construction of a salient pole rotor is as shown in the figure at left. The rotor winding is provided on these poles and it is supported by pole shoes. The pictures below show the stator and rotor of a hydroelectric generator and the rotor of a turbine generator. The rotor winding is provided on these poles and it is supported by pole. Salient pole synchronous generator power angle curve.
Olivian chiver, liviu neamt, mircea horgos and zoltan erdei. The device to measuring of the load angle for salientpole. The dc power required for excitationapproximately one to a. The salient pole rotor often consists of several separately wound pole pieces, bolted to the frame of the rotor. The rotor part consists of field poles and stator part consists of armature conductors. Actually, salient pole generators would be preferred in all cases. The effects of armature reaction in a salientpole synchronous generator. As a result, the ac generator is the most important means of producing electrical power. Most synchronous generators that have brushless exciters also use slip rings and brushes as an auxiliary source of field dc current in emergencies. Shorted turns in salient pole rotor windings result in an asymmetric distribution of magnetic flux around the rotor. The problem is that the centrifugal forces at high rpm i. Because by the formula 120 times frequency equals product of rotor speed and number of poles and considering 3000 rpm as the max speed in india for a mini. Pdf electric machines by dp kothari and ij nagrath pdf.
The phrase salent pole is used to specify a specific internal. Pdf analysis of salientpole synchronous generators operating in. The rotation of field poles in the presence of armature conductors induces an alternating voltage which results in electrical power generation. Designed, built and tested in the motor factory, solid salient pole rotors are suitable for applications requiring long duty cycles. Explained the difference between salient pole and non salient pole rotor compare salient pole and cylindrical rotor difference between salient pole and c. It consists of a coil of wire through which a current flows. Download fulltext pdf study of salient poles synchronous generator by finite elements analysis conference paper pdf available may 20 with 1,061 reads. If the machine is not connected to a load no armature current flowing, the terminal voltage will be. Ee 340 spring 2011 university of nevada, las vegas. Now, we will derive the torque of a salient pole rotor synchronous motor. Abrasive dust from the surrounding atmosphere carried into the interior of a motor or generator by. The equivalent circuit of a synchronous generator the voltage ea is the internal generated voltage produced in one phase of a synchronous generator.
Salient pole rotor winding failure mechanisms and repair. The stationary field synchronous machine has salient poles mounted on the. The red arrows indicate the direction of the flux produced by the field windings. Conducted experiment proves that third harmonic th component of salient. Study of salient poles synchronous generator by finite. In fact, a given synchronous machine may be used, at least theoretically, as an alternator, when driven. As the speed of the water turbine is slow hence more number of poles. The core has an edgewise wound yoke including an edgewise and helically wound strip of generally thin ferromagnetic material having at least one edge defining an outer circumferential surface on the edgewise wound yoke and extending generally axially thereacross. One of the two types of rotors typically installed within large generators is the salient pole rotor figure a. Salient pole machines are generally used for low speed applications. Difference between salient pole and non salient pole rotors or salient pole alternator and cylindrical alternators used in synchronous generator. The projected poles are made up from laminations of steel.
Us6791204b2 torque generation for salientpole synchronous. Synchronous generator salient pole vs non salient pole. And determine the full load regulation of a three phase synchronous generator by synchronous impedance method. The cooling medium, air or hydrogen is cooled by passing over pipes. This paper sets to present the dynamic model and simulation of a threephase salient pole. The salient pole type of rotor is generally used for slow speed machines having large diameters and relatively small axial lengths. Function of a generator rotor this section covers the generator fields function in two main areas. Solid salient pole motor synchronousmotor ge power. Compatibility design of non salient pole synchronous generator. Synchronous generator rotor construction round rotor salient pole two pole w s 3600 rpm four pole ws 1800 rpm eight pole ws 900 rpm fig.
1296 1299 116 421 1083 240 277 919 915 530 334 1018 1484 1076 1392 790 689 1446 145 739 669 178 688 65 861 1039 406 522 1042 1368 1063 782 1391 1250 921 248 772 844 818 890 1371 304 521 341 65 1408 123 1136 1428 607