Electrotechnique fondamentale 2 cours examen td tp. The voltage from the armature is applied directly to the field in the case of a generator. Shunt or separate excitation system leroysomer installation and maintenance 3972 en 02. This parallel configuration allows independent path of current for field winding and armature. These motors are very easy to miniaturize, and essential for very low powers and low voltages. This motor is used when both a high starting torque and good speed regulation is needed. Static exciters shunt and series in static excitation system, the excitation power is derived from the generator output through an excitation transformer. Types of dc generatorseparately excited and self excited. The differential compound machine is connected so the series and shunt fields are in magnetic opposition.
The performance characteristics of a dc machine are greatly influenced by the way in which the field winding is excited with direct current. Jul 11, 2019 a dc shunt motor also known as a shunt wound dc motor is a type of selfexcited dc motor where the field windings are shunted to or are connected in parallel to the armature winding of the motor. For a given excitation current or field current, the emf generated at no load e 0 varies in proportionally. Cours electrotechnique les moteurs a courant continu. Excitation systems can be defined as the system that provides field current to the rotor winding of a generator. Moteur a courant continu a excitation independante et a excitation serie i but. A compound dc motor connects the armature and fields windings in a shunt and a series combination to give it characteristics of both a shunt and a series dc motor. Modern dc generators with field coils are selfexcited generators which get started with the initial current in the field coils. Since they are connected in parallel, the armature and field windings are exposed to the same supply voltage.
Construction and principle of operation of the shunt dc motor. Nov 19, 2017 exercice corrige sur le moteur a courant continu a excitation shunt. Etudier le moteur a courant continu respectivement a excitation independante et a excitation serie, relever les caracteristiques electriques et electromagnetiques des deux ii rappel theorique. Separate field excitation dc motors are still sometimes used for driving machines at variable speed. Has both shunt and series field so it combines features of series and shunt motors. Speed control of dc shunt motor with field and armature rheostat control 79 2. Les circuits inducteur et induit sont alimentes par une tension constante. The circuit diagram of a short shunt dc motor is shown in the diagram below. Pdf les machines a courant continu et les transformateurs.
Scribd is the worlds largest social reading and publishing site. Types of dc generator separately excited and self excited the dc generator converts the electrical power into electrical power. In 210 mw set, the primary voltage of excitation transformer is 1575 kv. The exciter armature and the rectifier bridge are mounted on the synchronous generator rotor shaft and are interconnected electrically with the alternator revolving field. Types of dc motors and their applications electrical4u. The excitation system is comprised of two assemblies. Shunt motor or selfexcited generator the shunt connection is in which the field is connected in parallel, or shunt with the armature. A dc motor direct current motor has a lot of applications in todays field of engineering and technology. There are two methods of excitation of a dc machine. That is the reason behind naming it a dc shunt motor. It is particularly important to distinguish between two modes of shunt calibration which are referred to in this tech note, somewhat arbitrarily, as instrument scaling and instrument verification. For shunt excited generators, this results in zero input power to the avr, and the generator may be unable to force current flow long enough for downstream circuit interrupters to clear the fault, and the entire electrical system will be shut down. Dc machines with fixed excitation circuit speed constant e.
From electric shavers to automobiles dc motors are everywhere. Tp electrotechnique abdessemed djallal bouzidi mansour boussekra moteur a courant continu a excitation shunt tp 03 1 generalite. Basics of dc motors for electrical engineers beginners. Pdf cours electricite courant continu cours electricite. Feb 14, 2011 a moteur a excitation separee et moteur shunt alimentes sous tension fixe. Tp electrotechnique abdessemed djallal bouzidi mansour boussekra moteur a courant continu a excitation.
Basics of dc motors for electrical engineers beginners on photo. Adjusting the field resistance r f and thus the field flux adjusting the terminal voltage applied to the armature. The adequacies required to use the current initial excitation system supply 125 v dc supply. The less common method of speed control is by inserting a resistor in series with armature circuit. Exercice 1 corrige moteur a courant continu a excitation. Mg say phd, msc, ceng, frse, fiere, agci, dic, jf eastham, in electrical engineers reference book sixteenth edition, 2003. To cater to this wide range of applications different types of dc motors are used depending on the applicaition. The shunt excitation system can also be completed by a booster system for larger installations to allow for shortcircuit capability. Where a drop in speed between no load and full load greater than that obtainable with a plain shunt motor is required, a series winding may be added to assist the shunt winding, giving a speedtorque characteristic having any desired amount of droop. The excitation system is mounted on the side opposite the coupling.
Same voltage is applied to both shunt winding and armature in this motor. Excitation boost system ebs permanent magnet generator pmg. The dc shunt wound motor, running on direct current, has its field windings placed in parallel to the armature. Speed control of shunt dc motor two common ways in which the speed of a shunt dc machine can be controlled. Pdf cours electrotechnique les moteurs a courant continu. Speed control of dc shunt motor with field and armature. Appliquer letude precedente pour le moteur a excitation shunt. Three most important characteristic of shunt wound dc generators are discussed below.
Working principle from the above circuit diagram, we can conclude that if we want to increase the speed of the shunt motor, we will vary the field resistance. For the cumulative compound machine shown in the figure, both the series and shunt field produce flux in the same orientation. The magnetic flux in a dc machine is produced by the field coils carrying current. If the shunt field winding is only parallel to the armature winding and not the series field winding then its known as short shunt dc motor or more specifically short shunt type compound wound dc motor. Iii2moteur a courant continu a excitation shunt ou parallele. Iii2 moteur a courant continu a excitation shunt ou parallele. Dans les machines modernes, on utilise plutot une excitation sans balais ni bagues constituee dun alternateur triphase a induit tournant et dun redresseur tournant. Jan 08, 2014 fonctionnement moteur demarrage du moteur a excitation separee au demarrage. Excitation and automatic voltage regulator system 89 extinguishing chambers of magnetic arc blow, and a command bar for common operation of the main contacts and the insertion contact of the unload resistance. In electrical terms, parallel is generally denoted as shunt. Both pmg and aux winding excitation support systems provide power to the avr independent of the. Methods of excitation separate excitation self excitation. Leroysomer avr r448 instruction manual pdf download. Shunt calibration of strain gage instrumentation shunt calibration relationships are sometimes required for different sets of circumstances.