This paper introduces a new method to track the saturation saliency in five-phase PMSM drives to obtain the rotor position through measuring the dynamic currents responses of the motor due to the IGBTs switching actions [20,21,22]. It uses the fundamental PWM waveform obtained using the multi-phase space vector pulse width modulation only. The saliency tracking algorithm used in the proposed method doesn’t only improve the quality of the estimated position signals but also guarantees a minimum current distortion in the motor currents through reducing the modifications introduced on the PWM waveform.
III. TWO-LEVEL THREE PHASE AND FIVE-PHASE VSI Multi-phase IM drives used for variable speed applications. The conventional multiphase VSI does not suitable for this application owing to the high amount of harmonics presented in the voltage waveforms. A space vector concept is used with a modified switching sequence to reduce the harmonics and also helps to maximize the fundamental voltage. Fig.1 shows the circuit diagram for 3-ϕ VSI fed IM drive comprises six power switches, two switches per leg. The pole voltage is equal to V dc when the upper switch is ON and it is zero when it is OFF. Fig.2 shows the circuit diagram for 5-ϕ VSI fed 5-ϕ IM drive comprises ten power switches, two switches per leg. The pole voltage is equal to Vdc when the upper switch is ON and it is zero when it is OFF. To avoid the direct short circuit of same leg switches, they switched opposite to each other. Phase to neutral voltages (Va ~ Ve) of 5-ϕ VSI can be expressed in terms of inverter pole voltages as given in equation (15) and (16) , . V j = 4 5 V j − 1 5 5 i,i≠j V j , if j < 5 (15)
This paper proposes a transformer connection scheme to transform the three-phase grid power to a five-phase output supply. The connection scheme and the phasor diagram along with the turn ratios are illustrated. A five-phase RL-load is used to prove the viability of the transformation system. The proposed connection scheme can be used in drive applications and may also be further explored to be utilized in multiphase power transmission systems.
“Transformer Geometry For Three-Phase To Five-Phase Transformation “, P.Mamta1, Beena singh2 1Department of Electrical Engineering, Lingaya University, (India) 2Assistant professor, Department of Electrical Engineering, Lingaya University, (India) “ International Journal of science Technology & Management” www.ijstm.com ,Volume No.04, Special Issue No.01, February 2015 ISSN (Print) 2394-1529, (Online) 2394-1537
ABSTRACT : In this paper, a dynamic modelling of five-phase induction motor is described in a step by step approach. A dq model based on transformation theory for five-phase induction machine is presented. A detailed implementation of an indirect-type five-phase field oriented control including the hysteresis-type pulse width modulation (PWM) current regulator is described. Simulations have been carried out for different load conditions.
The three-phase induction motor with squirrel-cage rotor is the workhorses of industry because of their low cost, rugged construction, low price, and easy to maintain, which employs a clever scheme of electromechanical energy conversion. On top of that, the interest on electric motor with higher number of phases are kept increasing due to certain advantages such as higher torque density and less torque pulsation. In this project, five-phase induction motor is introduced and its performance as compared to three-phase induction motor will be discussed. This five-phase induction motor may replace conventional three-phase induction motor where higher torque density application is required.
In the early 19 th century, there is rapid development in the power system application in many areas such as transmission, distribution and power system appliances. In the year 1970s, there is rapidly growth in the sector of machines . Therefore, there is an interest on five-phase motor drive system increased over years. Recently, multiphase systems are the focus of research due to their inherent advantages compared to the three- phase counterparts .
Abstract— The three-phase supply is available from the grid; there is a need to develop static phase transformation system to obtain Multi-phase supply from the available three-phase supply. Carrier Based PWM Technique and Special Transformer connection Technique are used to convert Three- phase supply to Five-phase supply. PWM Technique is most suitable for employing two-drive systems with variable frequency which is more complicated. Hence Special Transformer Connection method is used in applications requiring fixed voltage and fixed frequency supply. This model can be simulated by using ‘SIMPOWERSYSTEMS’ block sets of MATLAB/SIMULINK software.
For this project, the speed of the motor has control by space vector modulation. The five-phase voltage source inverter (VSI) is use to run five-phase induction motor. Space vector modulation has chosen as the switching scheme due to its easiness of digital implementation. Space vector modulation gives effective control of multiphase VSI because of large numbers of space vectors. Voltage source inverter (VSI) implemented using ten Metal-oxide Semiconductor Field Effect Transistor (MOSFET). The speed of the motor should follow the reference speed that give as input.
Abstract: This paper describes the decoupled torque and flux control of a two series connected five-phase Induction Machine (IM) drive that is supplied by a three-level fivephase SVPWM inverter, using a well known phase transposition in the series connection. At the first, the decoupled torque and flux controller is developed based on variable-structure control (VSC). Then, a sliding-mode (SM) flux observer in employed to estimate the stator flux; that uses a two reference frames which result in eliminating the speed adaptation. Moreover simple control strategy is introduced for three-level SVPWM voltage source inverter (VSI) that can be easily implemented in practice for a two-series fivephase IM drive. Finally, the effectiveness and capability of the proposed control method is verified by computer simulation.
“I hereby declare that I have read through this report entitled “Development of Direct Torque Control (DTC) Algorithm for Five-Phase Induction Machine” and found that it has complied with the partial fulfillment for awarding the degree of Bachelor of Electrical Engineering (Power Electronics and Drive)”.
Multi-Phase Machines are Ac machines characterized by a stator winding composed of standard number of phases. In today’s electric drive & Generation technology Multiphase machine has several advantages over the traditional three phase machine such as sinking the amplitude and raising the frequency of torque pulsation, reducing the rotor harmonic current per phase without increasing the voltage per phase, lowering the dc-link current harmonics and higher reliability, high fault tolerance. Earlier multiphase motor where not used widely because that the supply for the multi-phase motor was not available, with the advancement of the electrical technology there is a choice to get the multiphase motor supply system. The proposed specially connected transformer takes the conventional three phase supply and it will give the fivephase supply by proper combination of the secondary winding terminals. The induction motor (fivephase) feed by the fivephase output of the specially connected transformer. The performance of the motor is analysed under balanced as well as unbalanced supply conditions and also under stator fault conditions.
This project, rely on control of five-phase motor using Field Oriented Control (FOC) using MATLAB simulation and DSpace. Nowadays, controlling speed of fivephase motor becomes important aspect in many industries. The main objective of motor speed control is to keep motor at desired speed. In this project, DSpace will control five- phase induction motor. DSpace act as controller for fast voltage and current measurement. The DSpace is digital signal processor that will be connected to computer and will operated in real time. DSpace will connect to drive hardware and to motor using DSpace connector. DSpace also will control the parameter that tuned in computer. For speed, the project varies the frequency by using FOC by using of an inverter. The switching scheme will be applied to an inverter. The sinusoidal pulse width modulation switching scheme have used to find the signal. The FOC is used for switching the inverter to drive five-phase induction motor.
Fig.1. Schematic diagram of FivePhase Inverter In 180 deg mode of conduction, each switch conducts for 180 deg. At any particular instant, five switches are in ON state. Similarly in 144 deg mode of conduction, each switch conducts for 144 deg and at any particular instant, four switches are in ON state. The switching sequence for 180deg and 144 deg mode of conduction is shown in fig.2 and fig.3 respectively. Each of the five legs have switches a + a - , b + b - , c + c - , d + d - and e + e - respectively. In 144 deg conduction, there is dead time of 36deg which is enough is avoid shoot through. In 180 deg conduction mode, at a time five switches are in ON state. After every 36 deg, one switch changes its state. In 144 deg conduction, at a time four switches are conducting and after every 36 deg, two switches are changing state.
The purpose of designing and constructing of five-phase induction motor is to observe the characteristic of five-phase induction motor, because nowadays knowledge on five-phase induction motor are not matured yet. The three-phase and single-phase motors, there are widely used and many people have knowledge about it and can be found in almost every production machine today. Besides that, fivephase induction motor also are not widely available in the market, because majority of the application is design for three phase and single phase motor only.
The usual practice is to test the designed motor for a number of operating conditions with a pure sinusoidal supply to ascertain the desired performance of the motor . Normally, a no- load test, blocked rotor, and load tests are performed on a motor to determine its parameters. Although the supply used for a multiphase motor drive obtained from a multiphase inverter could have more current ripple, there are control methods available to lower the current distortion even below 1%, based on application and requirement. Hence, the machine parameters obtained by using the pulsewidth-modulated (PWM) supply may not provide the precise true value. Thus, a pure sinusoidal supply system available from the utility grid is required to feed the motor. This paper proposes a special transformer connection scheme to obtain a balanced five-phase supply with the input as balanced three phase. The block diagram of the proposed system is shown in Fig. 1. The fixed voltage and fixed frequency available grid supply can be transformed to the fixed voltage and fixed frequency five-phase output supply. The output, however, may be made variable by inserting the autotransformer at the input side.
to 50 Hz. The performance of three-to-fivephase transformer is being studies through several experiments: static load of R and RL series impedance and finally with dynamic load (coupled of output transformer with five-phase induction motor with rated speed 3000 rpm and 3HP).
three-level diode-clamped converter in which the dc bus consists of two capacitors, C1, C2. For dc-bus voltage Vdc, the voltage across each capacitor is Vdc/2 and each device voltage stress will be limited to one capacitor voltage level Vdc/2 through clamping diodes. To explain how the staircase voltage is synthesized, the neutral point n is considered as the output phase voltage reference point. There are three switch combinations to synthesize three-level voltages across a and n.
For lack of basic four-step model of intelligence cycle author considers a substantial disparity of the data, information or snippets of information. It is these disparate elements, which then enter the next phase of the intelligence cycle – analysis. It is a fact that these ﬁ gures, data or pieces of information can be well developed in the intelligence analysis only to a limited extent. Larger quantities of data have resulted in the high-quality processing. This leads top management to its strategic decision-making with less quality materials. These problems can be solved by using the ﬁ ve phase model of intelligence cycle in Competitive Intelligence.
reliability [5-7]. Therefore, multiphase PMSG is very attractive for application of renewable energy . Several works on fivephase PMSG based wind turbine with back-to-back converters have been studied recently as in [5-7]. However, the cost, volume and the number of power electronic converters increase the complexity of this topology. Due to these disadvantages, the MC can be used as an alternative to DC-link voltage-sourced converter for wind energy conversion systems. In addition, the main advantages of the MC are the ability to generate sinusoidal input- output voltage and current and the possibility of adjusting input power factor [8-14]. On the other hand, MC application has been adapted for specific objectives and has not been generalized for wind power conversion systems based on multiphase PMSG generators as in [10-14, 17, 18].