Global journal 27 by Virtu & Foi

www.iiece.org GJESR RESEARCH PAPER VOL. 1 [ISSUE 7] AUGUST, 2014

ISSN:- 2349–283X

Three-phase Voltage Source PWM Rectifier Control with Discrete 12 Pulse Generator 1Rajendra

Singh Department of Electrical Engineering, M.M.M. University of Technology Gorakhpur, U.P, India. Email: raja03ee4444@outlook.com

2Avinash

Maurya Department of Electrical Engineering, M.M.M. University of Technology Gorakhpur, U.P, India. Email: avinashideal007@gmail.com

ABSTRACT: In this paper, we present a simulation study of pulse width modulation rectifier control with discrete 12-pulse generator. It works as an AC / DC rectifier. It gives DC voltage and current. To improve the voltage and current quality, A PID Controller is used. It reduced the harmonics of the input and output quantities. A 12-pulse generator used a yyd transformer that suppresses fifth and seven harmonics of currents. For improving the results low pass filter is used. Power electronics switches as thyristor family, transistor family, diodes, VSR switches, etc. are used for improving the level of switching. But best result gives GTOs. A GTO is a fully controlled device. ACSR conductor is improved magnetizing current and flux characteristics. Transformer losses decrease at low frequency and increase in high frequency. Corona loss limit increase with diameter of conductor. It works continuous and discontinuous mode of operation. Power factor, efficiency, THD, etc. parameters is also improved. Index Terms—Three-phase Controlled Voltage Source, Boost Inductors, 3-lags Bridge, Capacitors, Scaling gain, Logic Gates, Discrete space vector PWM generator, Discrete time Integrator, lookup table. Keywords: PWM RECTIFIER, Controller performance, Load voltage and load current, Control signal. 1. INTRODUCTION The future scope of the SVPWM rectifier is varied and all-inclusive owing to the coherent usage of power in the rectification process, and the load voltage is constant. The Three-phase rectifier has six switches that are switched using space vector technique. In general, the operation of a converter explained in the input signals, output signals, and the switching method used to obtain the desired output. The switching method of the switches in the converter is obtained in accordance with the digital electronic method. When V_CC supply connects to the switch enable. Grounds show the off position of the switch. All types’ power devices used in the rectifier circuit. [1]- [5]. In a threeThree-phase rectifier, the input AC voltages are

defined and the output DC voltage is dependent on the input quantities as well as the switching pattern of the rectifier. The switching pattern for any converter expressed as a function that is a mathematical representation of the switching pattern, called an existing function. The repetition of the switching patterns to obtain the desired output in a converter results in an existing function having intermittent ON and OFF periods, as the on-state is assumed to be a value 1, the pulses of the existence function have unit magnitude. The operating modes of the boost rectifier are the same as that of a threeThree-phase voltage source inverter. It operates eight different switching modes as boost rectifier. As explained earlier the ON and OFF states are assigned the values 1 and 0, respectively. [5]- [9].

PWM RECTIFIER

Fig.1. Basic circuit of pulse with modulation rectifier

GJESR RESEARCH PAPER VOL. 1 [ISSUE 7] AUGUST, 2014

ISSN:- 2349–283X

Fig.2 Line to line voltages and currents

Fig.3 Line to line inductance voltages and currents

The pulse width modulation rectifier is the new approach of rectification of voltages. Basically, IGBTs, MOSFETs, GTOs are used in rectifier. These power switches get the best performance. The power switches, switch at the different instant of time. The transmission line is equivalent a voltage source in series with an impedance. These voltage sources are and the common impedance z is combined of and . The subscripts indicate source voltage and source impedance. The three symmetrical line chokes of the resistance Ra and

the induction La. Switches, switching sequence are (6,1), (1,2), (2,3), (3,4), (4,5), and (5,6). Every one switch at the interval of 60 . At this moment, one switch is commuted and another switch is fired. When the operation is performed, the body MOSFET switch gets the continuous pulse at the different instant of time. This instant time decided by the space vector. , This is the phase’s equation that is converted time in the degree. The space vector PWM do six operating vector and two nonoperating vector. [10] – [12].

GJESR RESEARCH PAPER VOL. 1 [ISSUE 7] AUGUST, 2014

ISSN:- 2349–283X

Fig.4 PID Controller performance The input source voltages describe below = =

sin ( t + ) sin ( t + - 120o)

sin ( t + - 240o)

(3)

(1)

And line to line voltages

(2)

Vm sin ( t + 30)

(4)

Fig.5 Load voltage and load current

Vm sin ( t -90o)

(5)

Vm sin ( t + 90o)

(6)

- Modulator Voltage Component in the Stationary Coordinate - Firing Angle (deg)

vdc =

Vm cos Where

(7) is firing angle.

…as...bs …cs- Phases of three-phase system …1 …2 …0 - positive, negative, zero sequence …rms - root mean square

LIST OF MANUSCRIPTS

…1 …2 …3 …4 …5 …6 – sequence of GTOs

A. Special Symbols

…S – Source © Virtu and Foi

GJESR RESEARCH PAPER VOL. 1 [ISSUE 7] AUGUST, 2014

- Angular Frequency (rad) − Fundamental Frequency (

ISSN:- 2349–283X

C. Subscripts The space vector pulse width modulator generates six pulses. These controlling pulses control the six switches.

)

- Phase Angle (deg) -Voltage Signal of Phase A, B, C B. Units ..H...F- Units of Resistance, Inductance, Capacitance …MW- Unit of Power …kV …kA- Unit of Voltage, Current

These switches make an AC/DC converter. Each pulse width Modulation period makes a reference voltage that is the average of two adjacent space vectors e.g. . Everyone takes some period of time. The remaining period takes the non-operating period. The discrete SVPWM generator operates in the eight modes. Every mode has eight vectors. Each mode has changed by sequence.

Fig.6 Control signal voltage & current D. Abbreviations and acronyms

magnitude of the base vector must be 0 and 1. For setting the

E. AC – Alternating Current F. DC – Direct Current G. PWM – Pulse Width Modulation H. SVPWM – Space Vector Pulse Width Modulation I. PID – Proportional, Integral, Differentiator J. T – Time Period

component, the base vector taken as inputs to the -transformation. B. Sequence for switching

E. General Symbol Phase Voltages – Line Voltages Transmission Line Resistance, Inductance - Snubber Resistance, Capacitance DISCRETE 12-PULSE GENERATOR

For every 60° periods, “only” one Three-phase voltage must be higher. Complete period is divided into six periods. During the every period, two switches are operated. One switch operates for positive highest voltage and another for the negative highest voltage. This sequence is given in the GTO Bridge and Snubber circuit. The Gate Turn-off Thyristor snubber circuit prevents the unwanted rate of rise voltage and to limit the rate of current rise. So, switching frequency of bridge increased and switching time reduced. [12] Snubber circuit has

A. Input vector The input vectors are taking to set the magnitude of the angle in the radian. The

R_Sn>2 T_S/C_Sn (8) C_Sn=P/(〖2πf×1000 ×V〗_ab^2 )

GJESR RESEARCH PAPER VOL. 1 [ISSUE 7] AUGUST, 2014

In Simulation, R_S=1e^05 Ω R_ON=1e^03 Ω C_S=∞ F

ISSN:- 2349–283X

T_S=2e^(-06) f =50 H_Z

Fig.7 Flux and current characteristics of transmission line TABLE.1. TRANSMISSION LINE PARAMETERS

Repeated in the eight times in a complete period. C. Control Signal frequency (Hz) Control signal frequency is calculated by the pulse width modulation frequency that is determined by the period of PWM rectifier. (9)

D. Rectified Voltage These parameters are determined from the line to line voltage. Modulation index is varying to 0 and 1, Three-phase angle are calculated in the radian and frequency in the Hz.

(10) V. OPERATING MODES OF THE CIRCUITS The body MOSFET controlling states © Virtu and Foi

GJESR RESEARCH PAPER VOL. 1 [ISSUE 7] AUGUST, 2014

ISSN:- 2349–283X

Every switch has the two states: on-stage and off-stage. On-state occurs when switching voltage becomes zero and off-state occurs when switching currents becomes zero.

TABLE.3 FOR OVERLAPPING

The pulse width modulation rectifier has three operating modes: Discontinuous Conduction Mode, Conduction Mode and Overlap Mode. In the discontinuous mode, all upper side body MOSFET are open/closed at a time. In this way, all body diode is then switched off. In the conduction mode, two bodies MOSFET switched-on at the instant when one positive and one negative line to line voltages becomes higher. In this way, everyone makes six modes (6 1), (1 2), (2 3), (3 4), (4 5) and (5 6). In conduction mode, switching loss becomes reduced. In overlapping mode, three bodies MOSFET switch-on at the instant when positive and a negative voltage goes to the highest. In this way, everyone makes six modes are (6 1 2), (1 2 3), (2 3 4), (3 4 5), (4 5 6) and (5 6 1). The equations that govern an operating Threephase are the same whatever we work on a diode rectifier or a controlled rectifier.

VI. DESIGN OF SWITCHING PULSES

Let Solve truth table for pulses By the K-map for conduction ̅̅ ̅ ̅ ̅ ̅ , ̅ ̅, ̅ ̅̅ ̅ ̅ ̅ ̅ ̅ ̅ ̅̅ ̅ Transmission Line Parameter are =359.26 0 =359.26 -120 =359.26 Base Power per Phase (VA) =100 PQ Tolerance (PU) = 1 Max Iteration = 50 Swing Bus is used.

TABLE.4 SWITCHING VOLTAGE AND SPACE VECTOR

Let Solve truth table for pulses By the Kmap for conduction ̅̅ ̅ , ̅ , ̅̅ ̅ ̅, ̅ ̅̅ ̅ S5=A ̅ ̅ TABLE.2 FOR CONDUCTION PHASE

Resistance Matrix R (

)

[

]

Inductance Matrix L (H/km) [

]

Capacitance Matrix (F/km) [ Sequence Resistance Matrix

]

GJESR RESEARCH PAPER VOL. 1 [ISSUE 7] AUGUST, 2014

]( =[ =[ Sequence Inductance Matrix ]( =[ =[

ISSN:- 2349–283X

)

Sequence Capacitance Matrix ]( =[ =[

]

) ]

Fig.8 Discrete synchronized 12-pulse generator with PWM rectifier

V. SIMULATED OBSERVATIONS To get the best rectifier performance, to use the programmable voltage source and short transmission line. The parameter for simulation used 10 ohm, 10 mH, source parameters, DC side low pass filter 0.01 F, and it controls the ripples of DC voltage, current. Integrator controller controls transient and the steady states’ responses as rise time, delay time, peak overshoots, errors, stability. The DC output voltage variation does not affect. The space vector control every 60 degree width, all vector control in a sequence in every sector, every sector have different sequences of vector operating periods. VI. CONCLUSIONS This paper presents the real-time application of pulse width modulation rectifier control with discrete 12-pulse generator. The compensation of the load current has been short out to using a controlled AC/DC converter. The advantage of the pulse width modulation rectifier short out rapid change in load current in rapid time. The switching frequency of the PWM rectifier is fast about 5 KHz.

Transient response and Steady-state response of the DC link voltage has been improved. The operation of PWM reciter has been successful in the mat lab software. Low pass filter is about 1 F for successful DC operation. PWM generator generates 12-pulse. In all pulses 6-pulse are stopped because each is useless for this experiment. The harmonics presents in this operation . The disadvantage of this operation, low pass filter are more sensitive and effective. ACKNOWLEDGEMENT This research is supported by the Dr.A.N.Tiwari. Currently, he is a Professor of electrical engineering with the Madan Mohan Malaviya University of Technology, Gorakhpur, (UP)India. He is actively involved in teaching, researching and lecturing in Power Electronics. He has published more than 50 technical papers. Many people have contributed to this paper and suggestions based on their classroom experience as a professor or student. I would like to all persons.

GJESR RESEARCH PAPER VOL. 1 [ISSUE 7] AUGUST, 2014

REFERENCES [1] Dae-Woong Chung,”Minimum-Loss Strategy For Three-ThreephasePWM Rectifier, IEEE Transactions On Industrial Electronics, Vol. 46, No. 3, June 1999 [2] Syed Abdul Rehman Kashif, “ThreeThree-phase Sinusoidal PWM Rectifier,” university of Engg.and Technology, Lahore. 23 Aug 2010, www.mathwork.in. [3] Michal Knapczyk*, Krzysztof Pieńkowski*, “High-Performence Decoupled Control of PWM Rectifier with Load Compensation,” nProc. 16th Int. Telecom. Energy Conf., Apr. 11–15, 1994, pp. 165–170. [4] Knapczyk M., Pieńkowski K., Analysis Of Pulse Width Modulation Techniques For AC/DC Line-Side Converters, Scientific Papers of the Institute of Electrical Machines, Drives and Metrology of the roclaw University of Technology, No. 59, Studies and Research, No. 26, Wroclaw, 2006. [5] Christophe Batard, Frédéric Poitiers, Christophe Millet and Nicolas Ginot, “Simulation of Power Converters Using Matlab-Simulink,” inProc. Chapter 3 http://dx.doi.org/10.5772/46419. [6] J. W. Kolar, T. Friedli, and M. Hartmann, “Three-Three-phase PFC Rectifier and Ac–Ac Converter Systems—Part I, Tutorial,” inProc. 26th IEEE Appl. Power Electron. Conf. Expo., Mar. 6–10, 2011, pp. 1–268. [7] Blasco-Giménez R., Pena R., Cárdenas R., Cartes J., Load Compensated Non-linear Voltage Control of a Boost Type Rectifier, International Conference on Power Electronics and Motion Control-EPE-PEMC`00, Košice, 2000. [8] Kanelis K., Lorenz L., Stolze T., New Low Cost IGBT-Modules, Proceedings on International Conferences ZM Communications GmbH PCIM’01, Nuremberg, 2001. [9] Knapczyk M., Pieńkowski K., Robust Current Control Technique for BoosType AC-DC line-side Converter with Sliding-Mode Voltage Observer, Scientific Papers of the Institute of

ISSN:- 2349–283X

Electrical Machines, Drives and Metrology of the Wroclaw University of Technology, No. 58, Studies and Research, No. 25, Wroclaw, 2005. [10] Kwon B. H., Youm J. H., Lim J. W., A LineVoltage-Sensorless Synchronous Rectifier, IEEE Transactions on Power Electronics, vol.14, no.5, September 1999. [11] Rioual P., Pouliquen H., Louis J. P., Nonlinear control of PWM rectifier by state feedback linearization and exact PWM control, IEEE PESC’94 Proceedings, June, 1994. [12] Rodríguez J. R., Dixon J. W., Espinoza J. R., Pontt J., Lezana P., PWM Regenerative Rectifiers: State of the Art, IEEE Transactions on Industrial Electronics, vol.52, no.1, February 2005.