Space Vector Pulse Width Modulation

Space Vector Pulse Width Modulation Avinash Mishra, Swaraj save, Rohit Sen Abstract— The rapid development of high switching frequency power electronics in the past decade leads towards wider application of voltage source inverters in AC power generation. Therefore, this prompts the need for a modulation technique with less total harmonic distortion (THD) and fewer switching losses. Space vector pulse width modulation (SVPWM) provides a better technique compared to the more commonly used PWM or sinusoidal PWM (SPWM) techniques. SVPWM is a more sophisticated technique for generating a fundamental sine wave that provides a higher voltage, high reduction in the dominant harmonics and lower total harmonic distortion when used in an inverter. In SVPWM the complex reference voltage phasor is processed as a whole, therefore, interaction between three phases is exploited, and this strategy reduces the switching losses by limiting the switching. This paper will analyze the working and design of SVPWM and will provide comparative analysis of improved quality with the conventional methods.

Abstract- Inverters inherently have the property of controlling output frequency but the output volt- age can’t be varied. Usually to vary output voltage we have to vary supply voltage which is not always possible for this reason PWM techniques gained momentum. Basic aim of PWM technique is to control output voltage and harmonic reduction. Pulse-width modulation (PWM), or pulse- duration modulation (PDM), is a commonly used technique for controlling power to inertial electri- cal devices, made practical by modern electronic power switches. Here we apply PWM techniques like Sinusoidal pulse width modulation (SPWM) and Space Vector Pulse width Modulation (SVPWM) to inverter and study its performance.

saisudheer.git@gmail.com sripathirishikesh@gmail.com Abstract: Power Quality problems encompass a wide range of disturbances such as voltage sags, swells, flicker, harmonics distortion and interruptions. The strategic deployment of custom power devices has been proposed as one of the means to protect sensitive loads from power quality problems such as voltage sags and swells. The Dynamic Voltage Restorer (DVR) is a power electronic device that is used to inject 3-phase voltage in series and in synchronism with the distribution feeder voltages in order to compensate voltage sag and similarly it reacts quickly to inject the appropriate voltage component (negative voltage magnitude) in order to compensate voltage swell. The principal component of the DVR is a voltage source inverter that generates three phase voltages and provides the voltage support to a sensitive load during voltage sags and swells. Pulse Width Modulation Technique is very critical for proper control of DVR. Sinusoidal Pulse Width Modulation (SPWM) and Space Vector Pulse Width Modulation (SVPWM) control techniques are used for controlling the DVR. In this work, the operation of DVR is presented and the control technique used for voltage source inverter is Space Vector PWM technique. Space vector PWM can utilize the better dc voltage and generates the fewer harmonic in inverter output voltage than Sinusoidal PWM technique. This work describes the DVR based on Space Vector PWM which provides voltage support to sensitive loads and is simulated by using MATLAB/SIMULINK.

I. INTRODUCTION In Power System applications one major problem in output is distortion. For mitigation of this different methodologies have been used. With advances in Solid-State Power Electronics Devices, various Pulse Width Modulation (PWM) techniques have been developed for Industrial applications. Shao-Liang An, Xiang-Dong Sun, Member, IEEE, Qi Zhang, Yan-Ru Zhong, and Bi-Ying Ren has been studied SVPWM Technique and this paper shows further study and talk about reduction of total harmonic distortion. PWM is a means of transmitting information in a series of pulses, where the data being transmitted is encoded in the width of the transmitted pulse. In the Space Vector Pulse Width Modulation technique, the duty cycles are computed rather than derived through comparison as in Sine Pulse Width Modulation. The SVPWM technique can improve the fundamental component by up to 27.39% than SPWM. This paper discusses the studies of Space Vector PWM technique (SVPWM). The simulation results show that the SVPWM technique has lower total harmonic distortion than the PWM technique.

VIII. CONCLUSION In this research paper induction motor speed control using space vector pulse width modulation is designed through MATLAB software and also tested successfully by evaluating the parameters like voltage, stator current, and flux. It is due to its characteristics like good power factor, extremely rugged and high efficiency. This scheme provides all the available switching states and switching sequences based on two general mappings and calculates duty cycles. This scheme also leads to be able to adjust the speed of the motor by control the frequency and amplitude of the stator voltage, the ratio of stator voltage to frequency should be kept constant. Besides the design and implementation of an induction motor using by MATLAB Simulink is trouble free and uncomplicated.

Abstract— The latest trends in modern industrial applications are the use of variable voltage & frequency supply to the AC drives from a three phase voltage source inverter (VSI) by using different types of Pulse Width Modulation (PWM) schemes. The most commonly used PWM schemes for three-phase VSI are carrier-based sinusoidal PWM and space vector PWM (SVPWM). Researchers adequately prefer the use of space vector PWM (SVPWM) because of their easier digital realization and better dc bus utilization. In this paper the theory and implementation of the Space Vector Pulse Width Modulation for two level VSI have been explained using MATLAB/SIMULINK environment and the inverter performance is evaluated in terms of Total Harmonic Distortion (THD).

− Reference value increases (or) decreases the pulse generation in the pulse generator. In the event that the contrast between the two regulation record terms is not as much as reference esteem , the proposed calculation yields the ideal exchanging edges. The cycle strategy is utilized to illuminate and discover minimization of the voltage THD. III. SPACE VECTOR PULSE WIDTH MODULATION FOR SST

Abstract: In adjustable speed drive system speed control techniques are generally essential. Therefore in order achieve this it requires variable voltage supply and frequency which is invariably obtained from a three-phase Voltage source inverter. Even though there are numbers of pulse width modulations scheme is used to obtain variable frequency and voltage supply from an inverter. It is less used than the space vector pulse width modulation. Because the SVPWM has several merits such as better dc bus utilization, easier digital realization over the other Pulse width modulation methods. In the space vector pulse modulation method with voltage / frequency control of induction motor drive is widely used in medium performance drive system. It is due to its characteristics like good power factor, extremely rugged and high efficiency. This scheme leads to be able to adjust the speed of the motor by control the frequency and amplitude of the stator voltage, the ratio of stator voltage to frequency should be kept constant. In this paper the voltage source inverter type space vector pulse width modulation model design and implementation has been done through MATLAB / SIMULINK software for the speed control of induction motor. In addition to these parameters like stator current, rotor current, torque and speed are obtained graphically.

Ruan Shihao, LIU Weiting,Wei Haifeng,Yan Pengyu,Yao Jinyi,Chen Jiaqi School of Electrical and Information, Jiangsu University of Science and Technology, Zhenjiang 212003, China Abstract ： The paper expounds the mathematical model of permanent magnet synchronous motor, which introduces the general principle of the direct torque control and the space vector pulse width modulation. In the MATLAB/simulink environment, the mathematical model of permanent magnet synchronous motor sets up a simulation model of the direct torque control which based on the theory of SVPWM. Each step and process of the simulation model is introduced in detail and finally the simulation result is obtained. The simulation result shows that the direct torque control system which based on the theory of SVPWM has a constant switch frequency, can reduce the torque ripple greatly, and improves the current waveform and flux linkage waveform. So it makes the system have a better dynamic and static performance and also verify the feasibility and effectiveness of the plan.

Advances in power electronics have led to an increased interest in voltage source inverters with pulse width modulation control of AC drives. A number of pulse width modulation (PWM) schemes are used to obtain variable voltage and frequency supply. The most widely used PWM schemes for three-phase voltage source inverters are carrier- based sinusoidal PWM and space vector PWM (SVPWM). There is an increasing trend of using space vector PWM (SVPWM) because of their easier digital realization and better DC bus utilization [1-3]. Moreover, it gives a higher output voltage for the same DC bus voltage, lower switching losses, and better harmonic performance in comparison to carrier based sinusoidal pulse width modulation [4-5]. The space vector pulse width modulation of a three level inverter provides the additional advantage of superior harmonic quality and larger under-modulation range that extends the modulation factor to 90.7% from the traditional value of 78.5% in sinusoidal pulse width modulation. This paper focuses on SVPWM implemented on an induction motor drive. The model of a three-phase voltage source inverter is presented based on space vector theory.

Key-Words :- SVPWM – Space Vector Pulse Width Modulation, VSI – Voltage Source Inverter 1. INTRODUCTION : Nowadays, the demands for the electronic products are getting higher due to the rapid advances in technology. The usage of electronic appliances now is a part of our live where it covers 80% of the performance in our daily activities. For example, machines and motors AC / DC are used by both small and large-scale industries to lift or move objects. The control of these motors are carried out by using the electronic controllers. Because the electronic controllers are more efficient. Most of the electronic equipment is called distortion current also known as non-linear load. This non-linear

Assistant Professor, Dept. of Electrical Engineering, University College of Engineering (A), Osmania University, Hyderabad, Telangana, India ABSTRACT: A major advancement in the research area of space vector pulse width modulation (SVPWM) in recent years is the introduction of the nearest three vector algorithm computational intensity is still a drawback of SVPWM methods in real time applications, especially in the case of multilevel inverter operation. To solve the problem of computational complexity in multilevel inverters due to the large number of space vectors and redundant switching states, a simple space vector PWM method is proposed. Based on this method, the location of the reference voltage vector can be easily determined and the calculation of dwell times becomes very simple. More importantly, the proposed method is general and can be directly applied to the cascaded H-bridge inverter of any voltage levels. This proposed method is tested for seven level and nine level cascaded H-Bridge inverter drive system and the simulated results were presented.

" I hereby declare that I have read through this report entitle "Modeling and Simulation of Space Vector Pulse Width Modulation for Three Phase Voltage Source Inverter" and found that it has comply the partial fulfillment for awarding the degree of Bachelor of Electrical Engineering (Power Electronic and Drive) "

Multi-level voltage source inverters offer several advantages such as a better output voltage with reduced ripple, reduction of voltage ratings of the power semiconductor switching devices and also the reduced electro- magnetic interference problems etc. This paper presents torque ripple reduction for high power induction motors driven by five-level inverter with the low inverter switching frequency limited around 0.5–1kHz. It also presents an application of simplified space vector pulse width modulation (SVPWM) method for five-level fed inverters feeding a three-phase Induction motor and compares the torque ripple of induction motor drive fed with conventional two-level inverter and five-level inverter.

KEYWORDS:Dynamic Voltage Restorer (DVR), Voltage Sag, Space Vector Pulse Width Modulation (SVPWM), Voltage Source Inverter (VSI). I.INTRODUCTION Power Quality problems consistof various disturbances such as voltage sags/swells, flicker, harmonics distortion, impulse transient, and interruptions [2]. Voltage sags can occur at any instant of time, with amplitudes ranging from 10 – 90% and a duration lasting for half a cycle to one minute [4]. Voltage swell is defined as an increase in rms voltage or current at the power frequency for durations from 0.5 cycles to 1 min. Typical magnitudes of swell are between 1.1 and 1.8 p.u. Voltage swells are not as important as voltage sags because they are less common in distribution systems.

Geethanjali College Of Engineering And Technology,Nannur Email.Id : 1 123saikishore@gmail.com, 2 rvdileepyadav7@gmail.com Abstract : In this paper, space vector pulse width modulation (SVPWM ) to control the speed of an induction motor fed with Zsource inverter is presented. In recent years, the field oriented control (FOC) of induction motor drive is widely used in high performance drive system due to its high efficiency, good power factor and extremely rugged property. The Z-source inverter is also introduced to the system which employs a unique LC network to couple the inverter main circuit to the diode front end.

m -is the rotor mechanical speed III. SPACE VECTOR PULSE WIDTH MODULATION In recent years VSI is widely used to generate a 3-phase variable frequency and variable voltage ac supply required for variable speed AC drives. The ac voltage is defined by two characteristics, namely amplitude and frequency. Hence, it is essential to work out an algorithm that permits control over both of these quantities. PWM controls the average output voltage over a sufficiently small period called sampling period or subcycle, by producing pulses of variable duty-cycle. The three-phase, two-level voltage source inverter (VSI) has a simple structure and generates a low-frequency output voltage with controllable amplitude and frequency by programming high-frequency gating pulses. In this VSI, there are a total of 8 states ( n 3 ). The V 1 to V 6 vectors are known as active voltage vectors and the remaining two vectors are known as zero voltage vectors.

5. Simulation and Experimental Results 5.1. Simulation Results To verify the proposed schemes, a simulation model for a three phase seven level cascaded H-Bridge inverter is implemented as shown in Fig.7. The simulations were performed by using MATLAB SIMULINK. It also helps to confirm the SVPWM switching strategy which can be implemented in a DSP. The simulation parameters for constant switching frequency for Space vector pulse width modulation are as following, 5KW rating, three phase load R = 100 ohms, L = 20 mH, each source V dc = 5V, switching frequency 2KHz. Phase leg voltages have been calculated and drawn for SVPWM Method shown in Fig.8.

The control method described in [11] uses a modular approach in order to control power flow and share of a microgrid system with mechanism to compensate the voltage harmonics. This work is based on the same methodology for potentially using the space vector pulse width modulation for micro-grid inverters tied to the utility grid in distributed generation configuration. A parametric analysis of both SPWM and SVPWM based micro-grid inverters has been performed to show a solution oriented comparative approach for power quality enhancement. After the performance evaluation and comparison between both the techniques, appropriate conclusions have been made.

Simran Bhalla, Dr. Jagdish Kumar ,Department of Electrical Engineering PEC university, Chandigarh, India E-mail: simran7693@gmail.com jagdishkumar@pec.ac.in Abstract- With advances in solid-state power electronic devices and microprocessors, various inverter control techniques employing pulse-width-modulation (PWM) techniques are becoming popular in AC motor drive applications. These PWM-based drives are used to control both the frequency and the magnitude of the voltages applied to motors .The most widely used PWM schemes for three-phase voltage source inverters are carrier-based sinusoidal PWM and space vector PWM (SVPWM). This review paper gives the idea of SVPWM applied to the two level inverter , its advantages over conventional PWM method and different types of switching sequence used in SVPWM.