Salient Pole Synchronous Generator - Report Example

Salient pole synchronous generator Student’s Name Institution Affiliation Introduction Salient pole synchronous generator is an AC electrical machine that works on low speed applications between 100rpm to 1500rpm with high torque. It consists of a stator and rotor with large diameter and short length of axial. The stator consists of windings and numbers of poles are usually ranged from 4 to 60, which are made from steel laminations rounded with field coils on a magnetic core, which are set to rotate in synchronous speed Ns=120f/P. Usually, salient pole generators are used in hydroelectric power plant where river water is stored in a dam. When the water is released it goes inside a turbine causing a spin, which makes the generator produce electric power. The air gap of salient pole rotor is non-uniform due to the structure of the rotor. Salient pole are mechanically weak therefore, it makes the maintenance high. The rotor has a large number of poles which means that if the machine has more poles it will run on slower speed, on the other hand if it has small number of pole it will go on high speed same as cylindrical rotor. As the machine runs on low speed it will give a high torque further more if the torque of machine is high more output volt age will be received. Also the winding core of salient pole rotor are separated unlike the cylindrical rotor. Aims and Objectives The major aim of this report is to explain what students learnt in various meeting that they had to study on how the Salient pole synchronous generator works. The students seek to understand what the different components of the Salient pole synchronous generator are and how they work. Also it will look on how the on the importance of the machine and how it works to maintain stable power supply. The different meetings that and what was learnt from each meeting is explained below. Literature Review/Background Research. There are several scholars who have looked into the, Salient pole synchronous generator the static eccentricity makes the fundamental frequency of the ripple doubles in the rotor current of salient-pole synchronous machines. The voltage harmonics and the rotor current ripple both can be used for the diagnosis. The air gap can produce the worn bearings, asymmetric thermal expansion and the bent shaft in the rotor and it can also create the high level of the static eccentricity. They stated in their study that the 4-pole 15-k VA generators were used to measure the innovative flange with the essay and exact regulation of the static eccentricity. It can cause the severe damage in the wind insulation, core as well as in the PM. The voltage harmonics and the rotor current ripple both can be used for the diagnosis. The rotor coincides the axis and it can displace it with the help of the stator shaft, and it will replace it from the salient pole (Haji and Toliyat, 2001). The static rotor eccentricity is used to raise the particular harmonics in the line-line terminal as well as in the no-load phase terminal voltage, both of them are smaller in the case of centered rotor. It used the 2ffrequency for the growth of the energy in the harmonics as well as it is used to enhance the components of the current rotor by the static eccentricity (Bruzzese and Joksimovic, 2011, pg. 1610). The researchers stated the air gap permeance between the static eccentricities with the salient-pole synchronous, and they highlighted some equation through which they can quickly judge the static displacement of the rotor center. They stated that to measure the static eccentricity, the winding rotor experiences and it can time-varying the air gap; this loophole is used to measure the rotor position at the salient pole. When the air gap is reduced, both are on the same synchronous stage. The proposed method has sensitive as well it can evaluate almost 6% of the static eccentricity drives to the opposite of the metal strips over the poles. The 2f frequency ripple is used to test the current loop of the embedded controller that is used to maintain the voltage. The researchers stated that to measure the static eccentricity, the winding rotor experiences and it can time-varying the air gap; this difference is used to measure the rotor position at the salient pole. The static eccentricity, the winding rotor experiences and it can time-varying the air gap, this gap is used to measure the rotor position at the salient pole (Keller et al., 2006, pg. 681). The voltage harmonics and the rotor current ripple both can be used for the diagnosis. When the air gap is reduced, both are on the same synchronous stage. The fault diagnosis of the static eccentricity in the permanent magnet in the synchronous motors in the different index. The linear combination if the shape factor, the head angle of the peak, wavelet decomposition of the detailed signals peak and auto-aggressiveness coefficients model as well (Ebrahimi et al., 2014). The winding rotor experiences and it can time-varying the air gap; this difference is used to measure the rotor position at the salient pole. According to Hong et al., (2012) the static eccentricity is a condition where the air gap is measured it can quickly gauge the position of the radical air gap which is fixed in the stator. The problem arises when it is used to measure the core ovality if the stator which is incorrect positioning does not change with the time (Hong et al., 2012). The air gap can produce the worn bearings, asymmetric thermal expansion, and the bent shaft in the rotor and it can also create the high level of the static eccentricity. They stated that the static Eccentricity could cause the serious problems in the thermal expansion when it is based on the rotor deflection. It can cause the severe damage in the wind insulation, core as well as in the PM. The stator in the time harmonics and the spatial that helps the including circuits of two phases that issued to evaluate the asymmetrical induction motor in the harmonics of the magnetic field. Salient pole synchronous generator is an AC electrical machine that works on low-speed applications between 100rpm to 1500rpm with high torque. It consists of a stator and rotor with a large diameter and short length of axial. The stator consists of windings and numbers of poles are usually ranged from 4 to 60, which are made from steel laminations rounded with field coils on a magnetic core, which is set to rotate in synchronous speed Ns=120f/P. Usually, salient pole generators are used in a hydroelectric power plant where river water is stored in a dam. When the water is released, it goes inside a turbine causing a spin, which makes the generator produce electric power. The air gap of salient pole rotor is non-uniform due to the structure of the rotor. The salient pole is mechanically weak. Therefore, it makes the maintenance high. The rotor has a large number of poles which means that if the machine has more poles, it will run on slower speed, on the other hand, if it has a small number of the pole it will go on high-speed same as the cylindrical rotor. As the machine runs at low speed, it will give a high torque Furthermore if the torque of engine is high more output voltage will be received. Also, the winding core of salient pole rotor is separated, unlike the cylindrical rotor. The researchers stated that to measure the static eccentricity, the winding rotor experiences and it can time-varying the air gap; this difference is used to measure the rotor position at the salient pole.The static eccentricity, the winding rotor experiences and it can time-varying the air gap, this gap is used to measure the rotor position at the salient pole (Keller et al., 2006). The voltage harmonics and the rotor current ripple both can be used for the diagnosis. When the air gap is reduced, both are on the same synchronous stage. The fault diagnosis of the static eccentricity in the permanent magnet in the synchronous motors in the different index. The linear combination if the shape factor, the head angle of the peak, wavelet decomposition of the detailed signals peak and auto-aggressiveness coefficients model as well (Ebrahimi et al., 2014, pg. 2020). The winding rotor experiences and it can time-varying the air gap; this difference is used to measure the rotor position at the salient pole. According to Tabatabaei et al., (2004), the rotating of the axis are based on the rotor coincides, and it can be used to set the axis of the symmetry. The rotor corresponds the shaft, and it can be displaced it with the help of the stator shaft, and it will be moved it from the salient pole. They discussed that the static eccentricity condition of the salient pole synchronous machine and it could cause by the asymmetric geometrical system between the stator and rotor. The static eccentricities with the salient-pole synchronous and they highlighted some equation through which they can quickly judge the static displacement of the rotor center. The rotor coincides the axis, and it can displace it with the help of the stator shaft, and it will replace it from the salient pole. The voltage harmonics and the rotor current ripple both can be used for the diagnosis. When the air gap is reduced between stator and generator both are on the same synchronous stage (Tabatabaei et al., 2004, pg. 1552). The static eccentricity is a condition where the air gap is measured it can quickly gauge the position of the radical air gap which is fixed in the stator. The problem arises when it is used to measure the core ovality if the stator which is incorrect positioning does not change with the time (Hong et al., 2012, pg. 925). The air gap can produce the worn bearings, asymmetric thermal expansion, and the bent shaft in the rotor and it can also create the high level of the static eccentricity. They stated that the static Eccentricity could cause the serious problems in the thermal expansion when it is based on the rotor deflection. It can cause the severe damage in the wind insulation, core as well as in the PM. The stator in the time harmonics and the spatial that helps the including circuits of two phases that issued to evaluate the asymmetrical induction motor in the harmonics of the magnetic field. The air gap length is used to measure according to the steady-state and predict the transient performance of the machine in the static eccentricity. It is based on the wavelength and the air gap that is present in the stator. The stator in the time harmonics and the spatial that helps the including circuits of two phases that issued to evaluate the asymmetrical induction motor in the harmonics of the magnetic field. The air gap can produce the worn bearings, asymmetric thermal expansion and the bent shaft in the rotor (Faiz et al., 2009, pg. 160). The winding rotor experiences and it can time-varying the air gap; this difference is used to measure the rotor position at the salient pole. When the air gap is reduced both are on the same synchronous stage, the winding rotor experiences and it can time-varying the air gap. Project Management Due to the complex nature of the activities that were required to ensure that fully understanding of the machine is attained, a program was established. From the program the following Gantt diagram was drawn to assist in undertaking the whole project. Gantt diagram. Progress to Date. First meeting 18th Oct 2016 In most cases, salient poles consist of rotors that are in large numbers which are projected pole commonly referred salient poles that are mounted on wheels that are magnetic. The poles that are projected are made up of steel that is laminations in natures. On the poles, there is a rotor winding provided which is used in ensuring that the poles shoes are supported. According to the way that they are designed, salient pole rotors are such that they have an axial length that is shorter and a diameter that is larger. Due to the way that they are made, these machines are used on electrical equipment that is generally of lower speed let’s say 100 RPM to 1500 RPM. Since the rotor speed is of lower speed, then it will be necessary that there will be increased the number of poles to enable the machine to attain the needed frequency which is Ns = 120f / P therefore, f = Ns*p/120. This shows the proportion of the rate is equal to the number of the poles. In a typical situation, the number of salient poles is estimated to be between 4 to 60. When comparing its flux distribution with that of a non-salient pole rotor, it is relatively weak. This makes the generation of the emf waveform is not good as that of the cylindrical rotor. Generally, the salient pole rotors require damper windings that will prevent rotor oscillations when operations will be taking place. In most cases, salient pole synchronous generators can be used in hydropower plants. An image is showing a picture of salient pole. Salient pole synchronous generator is an AC electrical machine that works on low-speed applications between 100rpm to 1500rpm with high torque. It consists of a stator and rotor with a large diameter and short length of axial. The stator consists of windings and numbers of poles are usually ranged from 4 to 60, which are made from steel laminations rounded with field coils on a magnetic core, which is set to rotate in synchronous speed Ns=120f/P. Usually, salient pole generators are used in a hydroelectric power plant where river water is stored in a dam. When the water is released, it goes inside a turbine causing a spin, which makes the generator produce electric power. The air gap of salient pole rotor is non-uniform due to the structure of the rotor. The salient pole is mechanically weak. Therefore, it makes the maintenance high. The rotor has a large number of poles which means that if the machine has more poles, it will run on slower speed, on the other hand, if it has a small number of the pole it will go on high-speed same as the cylindrical rotor. As the machine runs at low speed, it will give a high torque Furthermore if the torque of engine is high more output voltage will be received. Also, the winding core of salient pole rotor is separated, unlike the cylindrical rotor (Gray, 2007, pg. 1620). When it comes to the eccentricity, they commonly divided into three types. The three categories are as follows; dynamic eccentricity (DE), mixed eccentricity (ME) and static eccentricity (SE). When it comes to static eccentricity, it is made in such a way that the symmetrical axis of the rotor will coincide with the rotor rotating axis, on the other hand, symmetrical stator axis is displaced according to the axis above. Where the air gap distribution is in a non-uniform manner, but the minimum air gap angular position is fixed this according to the above case. The figure below is an image of static concentric On the case of dynamic eccentricity, with respect to the rotational axis, it is only the rotor symmetrical axis that will be displaced. This will coincide with the symmetrical stator axis. The figure below shows a cross section of a faulty and healthy the cross section salient pole synchronous generator under static eccentricity. Looking into mixed eccentricity condition, both rotor and symmetrical rotation axes become displaced in respect with the stator rotation axis. When it comes to the mixed eccentricity all the three parts rotor, stator, and symmetrical rotational axes are moved with respect to one another. Under this, the fault diagnosis systems are the ones employed as a tool to protect and maintain the expensive systems against failure. Second meeting action on 1st NOV 2016 A Salient Pole Synchronous Generator, as shown in the figure below is differentiated from the round rotor machine through the constructional features that are in the field poles which have projected significant interpolar air gap in them. The construction features are commonly employed on machines that are usually coupled to the hydroelectric turbines which are of lower speed so that the Salient Pole Synchronous Generator that has multiple pole pairs that are differentiated from machines that are attached to high-speed steam turbines (3,000/1,500 rpm) that contain two- or four-pole structure. According to the way that they are designed, salient pole rotors are such that they have an axial length that is shorter and a diameter that is larger. Due to the way that they are made, these machines are used on electrical equipment that is generally of lower speed let’s say 100 RPM to 1500 RPM. Since the rotor speed is of lower speed, then it will be necessary that there will be increased the number of poles to enable the machine to attain the needed frequency which is Ns = 120f / P therefore, f = Ns*p/120. This shows the proportion of the rate is equal to the number of the poles. In a typical situation, the number of salient poles is estimated to be between 4 to 60. When comparing its flux distribution with that of a non-salient pole rotor, it is relatively weak. This makes the generation of the emf waveform is not okay as that of the cylindrical rotor. Generally, the salient pole rotors require damper windings that will prevent rotor oscillations when operations will be taking place. In most cases, salient pole synchronous generators can be used in hydropower plants (Gray, 2007, pg. 1560). Salient pole synchronous generator is an AC electrical machine that works on low-speed applications between 100rpm to 1500rpm with high torque. It consists of a stator and rotor with a large diameter and short length of axial. The stator consists of windings and numbers of poles are usually ranged from 4 to 60, which are made from steel laminations rounded with field coils on a magnetic core, which is set to rotate in synchronous speed Ns=120f/P. Usually, salient pole generators are used in a hydroelectric power plant where river water is stored in a dam. When the water is released, it goes inside a turbine causing a spin, which makes the generator produce electric power. The air gap of salient pole rotor is non-uniform due to the structure of the rotor. The salient pole is mechanically weak. Therefore, it makes the maintenance high. Third meeting action on 8th NOV 2016 There are several scholars who have looked into the, Salient pole synchronous generator the static eccentricity makes the fundamental frequency of the ripple doubles in the rotor current of salient-pole synchronous machines. The voltage harmonics and the rotor current ripple both can be used for the diagnosis. The air gap can produce the worn bearings, asymmetric thermal expansion and the bent shaft in the rotor and it can also create the high level of the static eccentricity. They stated in their study that the 4-pole 15-k VA generators were used to measure the innovative flange with the essay and exact regulation of the static eccentricity. It can cause the severe damage in the wind insulation, core as well as in the PM. The voltage harmonics and the rotor current ripple both can be used for the diagnosis. The rotor coincides the axis and it can displace it with the help of the stator shaft, and it will replace it from the salient pole (Haji and Toliyat, 2001, pg. 172). Fourth meeting action on 22nd NOV 2016 In determining Xq and Xd, the method used is quadrature and direct axis reactance commonly referred to slip test. Excitation to the is applied in the field winding and voltage of an alternatore it gets an induced an armature. But in the slip test, a three phase supply is applied to the armature, having voltage must less than the rated voltage while the field winding circuit is kept open. They are used to ensure that the current is balanced. Both Xq and xd are very important to ensure balanced voltage within the system. The diagram below indicates how the two work and they assist in ensuring balance of voltage. To ensure that the system is balanced it restores normalcy in the areas where abnormal voltage is seen. Salient pole synchronous generator is a very important system that should be well studied to ensure that they understood. There variety of ways that this generator can be applied. It has an eccentricity fault from manufacture in the rotor which makes it slightly not straight and in somehow if it gets overload it may cause damage to the stator windings. Engineers have detected this fault using several methods but in my research I need to detect this fault using a new method which is called offline method. Further research will be carried out from my supervisor in order to detect this fault with the new method. From this method, solutions can be developed which can help to fix this fault. To ensure safety then it is best that understanding on how every component work to ensure everything is on line to the expectation. List of References Bruzzese, C. & Joksimovic, G. 2011. Harmonic signatures of static eccentricities in the stator voltages and in the rotor current of no-load salient-pole synchronous generators. IEEE Transactions on Industrial Electronics, 58, 1606-1624. Ebrahimi, B. M., Roshtkhari, M. J., Faiz, J. & Khatami, S. V. 2014. Advanced eccentricity fault recognition in permanent magnet synchronous motors using stator current signature analysis. IEEE Transactions on Industrial Electronics, 61, 2041-2052. Faiz, J., Ebrahimi, B. M., Valavi, M. & Toliyat, H. A. 2009. Mixed eccentricity fault diagnosis in salient-pole synchronous generator using modified winding function method. Progress In Electromagnetics Research B, 11, 155-172. Haji, M. & Toliyat, H. A. 2001. Rotor eccentricity fault detection of a DC motor. Industrial Electronics Society, 2001. IECON'01. The 27th Annual Conference of the IEEE, 2001. IEEE, 591-596. Hong, J., Park, S., Hyun, D., Kang, T.-J., Lee, S. B., Kral, C. & Haumer, A. 2012. Detection and classification of rotor demagnetization and eccentricity faults for PM synchronous motors. IEEE Transactions on Industry Applications, 48, 923-932. Keller, S., Xuan, M. T. & Simond, J.-J. 2006. Computation of the no-load voltage waveform of laminated salient-pole synchronous generators. IEEE transactions on industry applications, 42, 681-687. Tabatabaei, I., Faiz, J., Lesani, H. & Nabavi-Razavi, M. 2004. Modeling and simulation of a salient-pole synchronous generator with dynamic eccentricity using modified winding function theory. IEEE Transactions on Magnetics, 40, 1550-1555. electrical easy.2016. salient pole rotor vs non-salient pole rotor. [ONLINE] Available at: http://www.electricaleasy.com/2014/03/salient-pole-rotor-vs-non-salient-pole.html [Accessed 8 November 2016] electrical engineering info. 2016. electrical machines. [ONLINE] Available at: http://www.electricalengineeringinfo.com/2014/11/difference-between-salient-pole-alternator-and-non-salient-pole-rotor-in-alternators.html. [Accessed 8 November 2016]. Gray, C. B, 2007. An Equivalent Circuit for the Salient-Pole Synchronous Machine. IEEE Transacions on Education, 1557-9638. Read More

When the air gap is reduced, both are on the same synchronous stage. The proposed method has sensitive as well it can evaluate almost 6% of the static eccentricity drives to the opposite of the metal strips over the poles. The 2f frequency ripple is used to test the current loop of the embedded controller that is used to maintain the voltage. The researchers stated that to measure the static eccentricity, the winding rotor experiences and it can time-varying the air gap; this difference is used to measure the rotor position at the salient pole.

The static eccentricity, the winding rotor experiences and it can time-varying the air gap, this gap is used to measure the rotor position at the salient pole (Keller et al., 2006, pg. 681). The voltage harmonics and the rotor current ripple both can be used for the diagnosis. When the air gap is reduced, both are on the same synchronous stage. The fault diagnosis of the static eccentricity in the permanent magnet in the synchronous motors in the different index. The linear combination if the shape factor, the head angle of the peak, wavelet decomposition of the detailed signals peak and auto-aggressiveness coefficients model as well (Ebrahimi et al., 2014). The winding rotor experiences and it can time-varying the air gap; this difference is used to measure the rotor position at the salient pole.

According to Hong et al., (2012) the static eccentricity is a condition where the air gap is measured it can quickly gauge the position of the radical air gap which is fixed in the stator. The problem arises when it is used to measure the core ovality if the stator which is incorrect positioning does not change with the time (Hong et al., 2012). The air gap can produce the worn bearings, asymmetric thermal expansion, and the bent shaft in the rotor and it can also create the high level of the static eccentricity.

They stated that the static Eccentricity could cause the serious problems in the thermal expansion when it is based on the rotor deflection. It can cause the severe damage in the wind insulation, core as well as in the PM. The stator in the time harmonics and the spatial that helps the including circuits of two phases that issued to evaluate the asymmetrical induction motor in the harmonics of the magnetic field. Salient pole synchronous generator is an AC electrical machine that works on low-speed applications between 100rpm to 1500rpm with high torque.

It consists of a stator and rotor with a large diameter and short length of axial. The stator consists of windings and numbers of poles are usually ranged from 4 to 60, which are made from steel laminations rounded with field coils on a magnetic core, which is set to rotate in synchronous speed Ns=120f/P. Usually, salient pole generators are used in a hydroelectric power plant where river water is stored in a dam. When the water is released, it goes inside a turbine causing a spin, which makes the generator produce electric power.

The air gap of salient pole rotor is non-uniform due to the structure of the rotor. The salient pole is mechanically weak. Therefore, it makes the maintenance high. The rotor has a large number of poles which means that if the machine has more poles, it will run on slower speed, on the other hand, if it has a small number of the pole it will go on high-speed same as the cylindrical rotor. As the machine runs at low speed, it will give a high torque Furthermore if the torque of engine is high more output voltage will be received.

Also, the winding core of salient pole rotor is separated, unlike the cylindrical rotor. The researchers stated that to measure the static eccentricity, the winding rotor experiences and it can time-varying the air gap; this difference is used to measure the rotor position at the salient pole.The static eccentricity, the winding rotor experiences and it can time-varying the air gap, this gap is used to measure the rotor position at the salient pole (Keller et al., 2006). The voltage harmonics and the rotor current ripple both can be used for the diagnosis.

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