Wind Energy SystemBy: Andy Brown, Basheer Qattum & Ali GokalAdvisors: Dr. Na & Dr. Huggins
OutlineIntroductionHardwareSoftwareResultsFuture Steps
History of Wind Energy Utilization
ADVANTAGES OF WIND POWERWind is free and with modern technology it can be captured efficientlyWind does not cause green house gases or other pollutantsAlthough wind turbines can be very tall each takes up only a small plot of landExcellent source for remote areas not connected to a gridWind turbines have a role to play in both the developed and third worldAvailable in a range of sizes meaning a vast range of people and businesses can use themEnvironmentally FriendlyEconomically Competitive
Goals
Output maximum power despite fluctuating wind conditions.
Utilize power electronics to perform conversions
Successfully implement a DSP board to have a greater degree of control over our system to harness optimal energy
To create a system that is applicable with real world industry
Functional Requirements (Hardware)Shall be able to produce .75 kilowatt but not more then 5 kilowattsShall be able to convert wind power to single phase AC powerMust be able to maximize wind power conversion
Wind-Electric SystemsInduction Generators, Directly Connected to the Grid
Doubly-Fed, Wound Rotor Induction Generators
Power Electronics Connected Generator
Top Level Diagram
Functional Description Sub SystemsGeneratorDiode RectifierBoost ConvertersInverter
Brushless DC MotorDue to complications with size and Lab requirements, PMSG still.Max Current5.4 AMax Speed3600RPMMax Voltage 160 VMax Power 750W
Brushless DC Motor=(120*f)/(poles)
FrequencyRPM3-phase-to-neutral51502.42060019.540120040.560180061802400821003000871203600104
Brushless DC Motor
Three-Phase Diode RectifierMax Peak Voltage1600VMax Peak Current 300AMax Current25AMax Voltage600V
Output of DC generator after 3phase diode rectifier w/1.5mF Cap V = I*R Vo=(1.35Vin VDiode)P = I*V =(120*f)/(poles)
Value of capacitor to ensure clear signalC=(Vp/2*f*Vr) =534FTherefore we used 1.5mF
Three-Phase Diode RectifierVin = 64.0 VVo = 84.0 VIo = 961 mASpeed = 3000 RPMR = 88P = 80.72W
VINRMSVOUTSIMULATIONVOUT THEORICIAL PERCENT ERROR1014.113.54.442028.5275.564056.5544.636084.5874.2801131084.07120169.51624.63
Three-Phase Diode RectifierOutput of DC generator after 3phase diode rectifier w/o CapVo = 85.0 VIo = 964 mASpeed = 3000 RPMCurrentDC Voltage
Three-Phase Diode RectifierOutput of DC generator after 3phase diode rectifier w/1.5mF Cap Vin = 64.0 VVo = 84.0 VIo = 961 mASpeed = 3000 RPMDC Voltage3 Voltage
Interleaved Boost Converter
Boost ConverterVo=Vin/(1-D), or for more accurate values, Vo= {[(VIn-VIGBT*D)/(1-D)] VDiode}
IGBT: Switching Freq up to 300kHzMax voltage at 600V Max current at 60A
V InputDuty-CycleFreqVout-expVout-actual 520%300006.257.5540%300008.339.01560%3000012.512.5580%3000025.024.25
Boost Converter
Most time consuming part of Boost converterGate Driver
Gate Driver Gate to emitter (pulse) 30VGate to emitter (cont) 20VMax Gate Current 250uAGate driver output+18V120/14 VAC-RMS 17.89VDCOutput up too 600VCurrent up to 2AShutdown mode for protection
Gate Driver
Software
Functional Description
DSP Board - TI TMS320F2812PWM Generation16-Bit16 PWM outputs0 V 3.3 VADC12-BitAnalog Input: 0 V - 3 V
Controller Implementation ProcessSIMULINKCODE COMPOSERDSP
Testing Circuit Single Channel Boost Converter
Simulation Open-Loop Controller
Testing Circuit Open Loop Controller
Testing Hardware Output Results
Sheet1
Duty CycleVo (scope)Vo (DSP)Vo (DSP) Scaled
20%6.0 V6505.2
30%6.8 V7405.9
40%7.5 V8606.9
50%8.8 V10108.1
60%10.4 V12109.7
70%12.9 V155012.4
80%16.7 V202016.2
Duty CycleVo (scope)Vo (DSP)
20%6.0 V5.2 V
30%6.8 V5.9 V
40%7.5 V6.9 V
50%8.8 V8.1 V
60%10.4 V9.7 V
70%12.9 V12.4 V
80%16.7 V16.2 V
Sheet2
Sheet3
Testing Hardware Output Duty Cycle: 20% Input Voltage: 5.00 V Output Voltage: 6.00 V
Voltage Controller Simulation
Voltage Controller
Voltage Controller Output
Voltage-Current Controller Simulation
Voltage-Current Controller
Boost Converter Controller VS. Interleaved Boost Controller
Interleaved Boost Converter Open-Loop Controller
Interleaved Boost Converter Open-Loop Controller
Interleaved Boost Converter Open-Loop Controller Output
Single Phase Inverter ControllerSinusoidal Pulse Width Modulation
Unipolar PWMVout = VdWhen T1,T4 is ONVout=-VdWhen T2,T3 is ONVout=0When T1,T3 or T2,T4 is ON
Unipolar PWM
LC FilterMagnitude Bode Plot for Second-Order LC Filter
LC Filter Chose L = .125mH Yields C = 240uF
Inverter Controller Simulation
Inverter Controller Simulation
Interver Unipolar PWM Controller
Inverter SPWM - Output
Future Work - ControllerClosed-Loop Voltage and Current Controller for Two-Channel Interleaved Boost ConverterMaximum Power Point Tracking ControllerSingle-Phase Inverter Controller with Unity Power Factor Correction
Interleaved Boost Converter Voltage-Current ControllerSame Controller as designedNeed to output two PWM signalThe second PWM signal has to been delayed by half the period
Interleaved Boost Converter Simulation
Maximum Power Point Tracking (MPPT)
MPPTPerturbation and Observation Method (P&O)
MPPT algorithm adjusts duty cycle to achieve
MPPT System Diagram
MPPT - Flowchart
MPPT Current Controller Design
Single-Phase Inverter Controller with Unity Power Factor Correction System Diagram
*********This will be a three stage system, starting with a diode-rectifier, followed by a two-channel interleaved DC-DC boost converter, and finally another IGBT switched inverter system. In order to implement the DC boost converter, the project will need control switches as well as some controller. The controller we want to use for this project is a DSP processor. The basic topology of the circuit is shown below, and if time permits, modifications will be made to the system in order to improve overall performance.**The whole reason we are using the 3 phase AC generator is because 3 phase AC can travel the farthest distance without having major voltage and current loses. Then this output will go into the diode rectifier where it will get rectified to DC. Following that our output travels to the interleaved boost converters and the reason being is that we always want to output at 120 AC so we will always have to boost up. And we are using two because it will make it smoorther. Finally going into our inveter where that output will be turned back to AC. **If we used the psmg we could ve changed the sinoisodal wave form however since were stuck using the DC motor produces trapizodal wave form .dc equation tehre are many coeffficdents but we do not really consider all of them because we are basically just mimiking the system**The reason e used frequency is because our induction motor used to drive our dc motor changes speed via frequency so if we change that frequency it will change the rpm***More info about equation..Vr=(Vp/2fc) reference our electronics book chp 4 electornsx 1,.using ohms law and P=I*V we can conclude that our power and voltage output meets ohms law. Using the line to dc conversion equation we find that the data meets the laws. ,..then talk about Cap
*****Current messy due to grounding issues**Igbt specs
****Gate driver specswhat input and out put your going to utlize.whats the main advantage of suing a gate driver (shut down) for protection***Gate driver specswhat input and out put your going to utlize.whats the main advantage of suing a gate driver (shut down) for protection***Gate driver specswhat input and out put your going to utlize.whats the main advantage of suing a gate driver (shut down) for protection***The motor will be powerful enough to turn the shaft of the permanentmagnet synchronous generator in order to produce the desired voltage. The three phasediode rectifier will convert the varying frequency and magnitude sinusoidal voltages fromthe permanent magnet generator into a smooth but fluctuating DC voltage. Then the DSPdriventwo channel interleaved boost converter will increase the DC voltage, improve thepower factor, decrease the total harmonic distortion, minimize the current and voltageripples, and output maximum power by using a maximum power point trackingalgorithm. Finally, the inverter will convert the DC voltage into a 120 Vrms AC voltage inorder to interface with the grid.***********************************************************Since wind turbines operate at variable speeds, a maximum power tracking controller has to be considered for optimizing the use of available wind energyP&O based MPPT algorithm is used because it has successfully tracked the MPOP of solar array and has been used in wind power applications as well The perturbation and observation technique essentially perturbs the voltage in the boostconverter by changing the duty cycle in small increments until maximum power isachieved.***Since wind turbines operate at variable speeds, a maximum power tracking controller has to be considered for optimizing the use of available wind energyP&O based MPPT algorithm is used because it has successfully tracked the MPOP of solar array and has been used in wind power applications as well The perturbation and observation technique essentially perturbs the voltage in the boostconverter by changing the duty cycle in small increments until maximum power isachieved.*****There are four conditions to search for MPOP: 1. If P > 0 and Vdc > 0, then the reference voltage is increased by Vdc .
2. If P > 0 and Vdc < 0, then the reference voltage is decreased by Vdc
3. If P < 0 and Vdc > 0, then the reference voltage is decreased by Vdc .
4. If P < 0 and Vdc < 0 then the reference voltage is increased by Vdc .
****