ISSN Vol.09,Issue.04, March-2017, Pages:

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1 ISSN Vol.09,Issue.04, March-2017, Pages: Simulation Exhibition of 220KW Wind Power Generation with PMSG Using Matlab Simulink K. INDRANI 1, DR. K. RAVI 2, S. SENTHIL 3 1 PG Scholar, Dept of EEE(PE & ED), SVCET, Chittoor, AP, India. 2 Associate Professor, Dept of EEE, SELECT, VIT, Vellore, AP, India. 3 Research Scholar, Dept of EEE, SELECT, VIT, Vellore, AP, India. Abstract: This paper presents 220KW Wind Turbine Exhibition using 5 no s of 44KW wind turbines which are connected in parallel. Nowadays all a Renewable sources are directly connected to grid system without any voltage distortion, constant power stability, reliability and power quality. The PMSG is a most advantages to make the wind turbine as gearless system and optimize the power losses, copper loss, mechanical friction loss, weight and noise. This is also eliminating a dc excitation system and full controllability of the system for maximum power extraction & grid interface. It mainly focused the grid interface with wind turbine design and also the voltage and current levels changes with respect to wind speed & blade pitch angle. The High-energy density magnets (rare-earth magnets) has allowed the realization of extremely high flux densities in the PMSG generator, therefore rotor winding is not required. These in turn allow the generator to be of small, light, and rugged structure. The proposed model is accomplishing fault-ride through and grid support. There is no current circulation in the rotor to create a magnetic field, so that the rotor of a PMSG generator does not heat up. Cool down stator is easy because of it is on the periphery of the generator and it is static. There is no noise in the systems and the mechanical contacts and the driving converter switching frequency could be above 20 khz producing only ultrasound inaudible for human beings. The simulation results were obtained and tested with real time parameters. Keywords: Wind Turbine, PMSG Generator, Diode Rectifier, Inverter PWM Generation, Grid Connecting System. I. INTRODUCTION With the improve of industrialization energy demand will increase day by day. So that only the conventional energy sources such as hydro thermal nuclear may not serve over the life period. To overcome this we move on to the renewable energy sources like Wind, Solar, Pico Hydel and etc. Some researching departments indicate that energy will be triple by Currently we are using 15 to 20% of renewable energy sources of total demand. Main renewable energy sources are solar and wind. The Fig. 1 shows the wind energy conversion system to the grid and how active power will change with respect to the wind speed and blade 2017 IJATIR. All rights reserved. pitch angle, as now a days with advent increase technology of power electronics we have much easier to control over active and reactive power. Wind is a form of air in motion due to pressure gradient that is caused by the solar energy irradiating the earth. The KE energy wind is used to impact the rotational motion of wind turbine. Fig.1. Proposed Wind plant. The shaft of wind turbine will be connected to the shaft of wind electric generator. The electric generator can provide power to the stand alone system and provide power to grid. Stand alone system: employed to cater the power needs to the small turbines, mainly these are constructed to avoid transmission costs. Grid connected system: In these integrate renewable energy resources to the grid which leads to increased energy efficiency, robust system, and voltage support, diversification of energy resources,reduced transmission losses and reliability of the system. As the power electronic devices which increased in wind turbine generation system even power controllability much easier but also it can introduce much harmonics in the system.to increase power capacity to the grid number wind turbines connected in parallel. Permanent magnet machines are today manufactured up to rated power up to 6MW.In order to convert wind energy to grid many technologies are invented in that simplest is PMSG with diode rectifier. The harmonics will be simulated with frequency of 3KHZ or higher. Moreover GTO s which have self ON and OFF

2 K. INDRANI, DR. K. RAVI, S. SENTHIL characteristics it cannot capable of high switching frequency P m = 1 about 1KHZ.So this is not enough to reduce the harmonics ρac 2 pv 3-8 up to this limit. And also transistors are the range up to 100- P m = 1 200KW.so that now a days we used the IGBT which capable π P to handle large phase current and voltage up to 1700V. m = KW II. POWER CALCULATION The tip speed ratio (λ) can be defined as the ratio of the angular rotor speed of the wind turbine to the linear wind speed at the tip of the blades. It can be expressed as follows: (1) Where λ Tip speed ratio, R - Wind turbine rotor radius,v w - Wind speed and ꙍt- Mechanical angular rotor speed of the wind turbine. The output power of the wind turbine, can be calculated from the following equation T m = P 1 ꙍt 1 T m = = 140N/m Power Input: 44KW of 5numbers of wind turbines P m = 5 44 = 220KW Output KVA=output voltage output current = =25000 =250KVA IV. EXISTING SYSTEM Where P m Output power, A-area under blades, R - Wind turbine rotor radius, ρ -Air density, V w -Wind speed C P Power coefficient which defined as (2) Where λ-tip speed ratio, β-blade pitch angle (3) The torque value can be calculated as, Where T m -mechanical torque, ρ -air density, A-area under blades (A = πr 2 ), R - Wind turbine rotor radius, C T --Torque coefficient. V w -Wind speed. III. THEORETICAL CALCULATIONS OF POWER For the 44KW wind system the main requirements are β = 10 V w = 40m/s ꙍt = rad/s R = 1.02m ρ = λ = ꙍt R V w λ = 5 40 =8.01 C p = β sin π λ β λ 3 β 6 C p = ( 10) sin π ( 10) = (4) Fig.2. Simulation model for existing system. A 9-MW wind farm consisting of six 1.5 MW wind turbines connected to a 25-kV distribution system exports power to a 120-kV grid through a 30-km, 25-kV feeder as shown in Fig.2. A 2300V, 2-MVA plant consisting of a motor load and of a 200-kW resistive load is connected on the same feeder at bus B25. Both the wind turbine and the motor load have a protection system monitoring voltage, current and machine speed. The DC link voltage of the DFIG is also monitored. Wind turbines use a doubly-fed induction generator (DFIG) consisting of a wound rotor induction generator and an AC/DC/AC IGBT-based PWM converter. The stator winding is connected directly to the 60 Hz grid

3 Simulation Exhibition of 220KW Wind Power Generation with PMSG Using Matlab Simulink while the rotor is fed at variable frequency through the AC/DC/AC converter. The DFIG technology allows extracting maximum energy from the wind for low wind speeds by optimizing the turbine speed, while minimizing mechanical stresses on the turbine during gusts of wind. The optimum turbine speed producing maximum mechanical energy for a given wind speed is proportional to the wind speed. For wind speeds lower than 10 m/s the rotor is running at sub synchronous speed. At high wind speed it is running at hyper synchronous speed. Open the turbine menu, select "Turbine data" and check "Display wind-turbine power characteristics". The turbine mechanical power as function of turbine speed is displayed for wind speeds ranging from 5 m/s to 16.2 m/s. The DFIG is controlled in order to follow the red curve. Turbine speed optimization is obtained between point B and point C on this curve. Another advantage of the DFIG technology is the ability for power electronic converters to generate or absorb reactive power, thus eliminating the need for installing capacitor banks as in the case of squirrel-cage induction generators. Fig.3. Simulation model for existing system. A. Turbine Response to A Change In Wind Speed Open the "Wind Speed" step block specifying the wind speed. Initially, wind speed is set at 8 m/s, then at t = 5s, wind speed increases suddenly at 14 m/s. Start simulation and observe the signals on the "Wind Turbine" scope monitoring the wind turbine voltage, current, generated active and reactive powers, DC bus voltage and turbine speed. At t = 5 s, the generated active power starts increasing smoothly (together with the turbine speed) to reach its rated value of 9 MW in approximately 15 s. Over that time frame the turbine speed will have increased from 0.8 pu to 1.21 pu. Initially, the pitch angle of the turbine blades is zero degree and the turbine operating point follows the red curve of the turbine power characteristics up to point D. Then the pitch angle is increased from 0 deg to 0.76 deg in order to limit the mechanical power. Observe also the voltage and the generated reactive power. The reactive power is controlled to maintain a 1 pu voltage. At nominal power, the wind turbine absorbs 0.68 Mvar (generated Q = Mvar) to control voltage at 1pu. If you change the mode of operation to "Var regulation" with the "Generated reactive power Qref " set to zero, you will observe that voltage increases to pu when the wind turbine generates its nominal power at unity power factor. Switching Ratio (Carrier Frequency/Output Frequency): Determines the frequency (F c ) of the two triangular carrier signals. B. Modulation Index Specify the modulation index to control the amplitude of the fundamental component of the output voltage of the converter. The modulation index must be greater than 0 and lower than or equal to 1. The parameter is visible only when the internal generation of modulating signal (s) check box is selected. V. EXISTING SIMULATION RESULTS Fig.4. Output active and reactive power,v dc. F c = Switching Ratio Output Voltage Frequency The Switching ratio parameter is visible only when the Mode of operation parameter is set to Synchronized. Internal Generation of Modulating Signal (s): When this check box is selected, the block generates the reference signal as shown in Fig.3. The parameter is visible only when the Mode of operation parameter is set to Unsynchronized. Fig.5. Input wind speed and pitch angle.

4 With the use of DFIG there will be disturbances in the active and reactive power of the system are shown in Figs.4 & 5. But by using the PMSG sytem grid disturbances can be reduced and also cost of sytem will be less.dfig require increasing gearbox between wind turbine and generator where as the PMSG system has sufficient number of poles to allow direct drive. VI. PROPOSED SYSTEM The five numbers of 44KW wind turbines connected in parallel to exhibit the power output as 220KW. The figure shows the proposed model for 220KW wind plant and simulated using MATLAB. The results were obtained and it will be tested with grid parameters are shown in Figs.6 & 7. K. INDRANI, DR. K. RAVI, S. SENTHIL B. Proposed Model of Wind Turbine The proposed wind turbine is shown Fig.8 and results were shown in Fig.9. Fig.8. Simulation circuit for wind turbine. Fig.6. Simulation Circuit for proposed model. A. Simulation Results Fig.7. Simulation Results for proposed model. Fig.9. Simulation Results for wind turbine.

5 Simulation Exhibition of 220KW Wind Power Generation with PMSG Using Matlab Simulink VII. CONCLUSION This proposed wind plant for 220KW using 5 no s of 44KW wind turbines are able to connect in parallel and meet the grid requirements. This proposed model power can get by changing wind speed and blade pitch angle. the maximum permissible angle β( i.e. ±30%), up to this level the wind turbine can maintain stability and the rotor speed maintained constant i.e rad/s. by changing the blade pitch angle in small limits there will be change in output power enormously. It is connected to the grid interface with wind turbine and also the voltage and current levels changes with respect to wind speed & blade pitch angle. There is no noise in the systems and the mechanical contacts and the driving converter switching frequency could be above 20 khz producing only ultrasound inaudible for human beings. The simulation results were obtained and tested with real time parameters. This system is also used for better connectivity of wind turbine into grid and maintains good reliability and power quality. VIII. REFERENCES [1]Modelling and Analysis of Wind Energy Conversion Systems Using Matlab P.Kumar*, A.Vinoth Kumar. [2]Simulation of Wind-Turbine Speed Control by MATLAB Furat Abdal Rassul Abbas and Mohammed Abdulla Abdulsada. [3]Grid Integration of Large DFIG-Based Wind Farms Using VSC Transmission Umer A. Khan, J. K. Seong, S. [4]H. Lee, S. H. Lim, and B. W. Lee. Feasibility Analysis of the Positioning of Superconducting Fault Current Limiters for the Smart Grid [5]Application Using Simulink and SimPower Systems. Umer A. Khan, J. K. Seong, S. H. Lee, S. H. Lim, and B. W. Lee.