pump.ppt
- 1. 1 PV BASED WATER PUMPING SYSTEM WITH GRID SUPPORT
- 2. 2 CONTENTs Problem definition Objective of the project Problem background Traditional solutions Constraints in old methods
- 3. Proposed model Operating modes Inverter control MATLAB design of case study Results and discussion conclusion
- 4. Problem definition • Seventy five percent of total global energy demand is supplied by the burning of fossil fuels. • Necessary to look towards renewable sources as a future energy solution. • At least agricultural loads can be operated with solar photo voltaic modules • Combined solution(PV+DC-DC+VSI+PMSM)
- 5. Objective of the paper • The main objective of my project is to design stand alone solar PV supplied PMSM drive for water pumping system. • An interlink Boost converter is used between solar PV panel and DC bus of PMSM drive to maintain constant dc voltage at dc link of VSI • Three phase VSI (Voltage Source Inverter) is controlled to supply PMSM under change in solar irradiation to regulate discharge of water.
- 6. Problem background • 80% of power by TPS • 14% by nuclear power systems • 6% by renewable resources • In India 80% of power produced by TPS • Losses • 60% at generating station • 21% at T&D systems • 19% is electrical output • Saving of 1KW of electrical power at load centre = saving of input fuel energy required to produce 6KW of electrical
- 8. SYSTEM DESCRIPTION • The proposed system consists PV based PMSM drive for water pumping system. • The proposed system consists of solar PV panel, a boost converter, a three phase VSI (Voltage Source Inverter)and a PMSM coupled with a centrifugal water pump.
- 9. • An individual PV cell is usually quite small, typically producing about 1 or 2W of power. • To increase the power output of PV cells, these cells are connected in series and parallel to assemble larger unit called PV module. • The PV array is connected to the DC to DC boost converter to increase the output voltage level. • The constant DC voltage is converted to the AC output using a VSI. Reference speed of PMSM is a function of solar irradiation.
- 10. DESIGN OF PV BASED PMSM DRIVE 1. Design of PV Array: The PV panel is designed for a 1.5 kW peak power capacity. One solar module consists of 36 cells in series. Each cell has an open circuit voltage of 0.6V and short circuit current of 4 A. Its one module has an open circuit voltage of 21.67 V and short circuit current of 4 A.
- 11. DESIGN OF PV BASED PMSM DRIVE • For the desired output voltage and current, the proposed SPV power generating system consists of 3 modules in parallel and 11 module in series to form a SPV array. This PV array can produce maximum 1.5 Kw power.
- 12. 2. Design of Boost Converter: The boost converter is used to feed the active power from PV array to the DC link capacitor connected VSI fed PMSM. The value of a boost inductor L is given as • L =VPV D/2*Δi*fs =2.67 mH
- 13. Design of Boost Converter • where D is duty cycle, • Vpv is output voltage of PV array, • fsw is switching frequency, • Δi is ripple in output current of PV array. • Considering Vpv =198.99V, Δi=10% of PV current and fsw =15 kHz, • The value of L is obtained as 2.67 mH.
- 14. Voltage Source Inverter • The apparent power rating of a VSI is given as, • S=√ P2+ Q2 • It is obtained as 1500 VA. The rms current through a VSI is given as, • I VSI =kW * 10 ³/ √ 3Vm =2.165A
- 15. CONTROL SCHEME 1.control of boost converter to maintain constant DC link voltage. 2. control of VSI in vector oriented mode to achieve fast dynamic response under change in solar irradiances and load conditions.
- 16. Dc link voltage conrol • From a PV operation point of view, you need to control the DC link voltage in order to control the output voltage of the PV panel and force it to the value of maximum power point as per the solar irradiation and cell temperature parameters.
- 17. Control of Boost Converter
- 18. • The DC bus voltage and the output of the DC PI controller is used to estimate the DC voltage rror at the kth sampling instant is as
- 19. • The output of the DC PI controller at the kth sampling instant is expressed as, • where kpa and kia are the proportional and integral gain constants of the PI controller
- 20. • Vdce (k) and Vdce (k-1) are the DC bus voltage errors in the kth and (k-1)th. • I* pv (k) and I* pv (k-1) are output of DC PI controller in the kth and (k-1)th instant needed for voltage control. • The reference and actual PV bus current are used to estimate the PV bus current error at the kth sampling instant as,
- 21. The PV bus current error (Ipve) is amplified using gain K and compared with fixed frequency carrier signal to generate switching signals for IGBT used in boost converter.
- 22. Control of VSI • Reference motor speed (ω* r) is the function of solar irradiation and used to track the maximum power. • Reference speed is compared with the measured rotor speed (ωr) and it provided speed error ωe.
- 23. • Speed error is processed using the speed PI controller, which provide the reference electromagnetic torque (T*ref). The reference torque (T* ref) is used to generate reference qaxis current (i*q) as follows.
- 24. • Speed error is processed using the speed PI controller, which provide the reference electromagnetic torque (T*ref). The reference torque (T* ref) is used to generate reference qaxis current (i*q) as follows,
- 25. • Similarly, from the sensed rotor speed of the PMSM, magnitude of d-axis PMSM current (i* d) is obtained which is consider zero below rated speed. • i*d =0
- 26. Reference current generation • Three-phase reference PMSM currents (i*a, i* b, i*c) are obtained using i*d and i* q and the rotor angular position in electrical rad/sec by inverse park transformation.
- 27. Pulse generation • Three phase reference currents (i* a, i* b, i*c) are compared with sensed PMSM currents (ia, ib, ic) and resulting current errors are fed to the PWM current controller for generating the switching signals.
- 28. PV based PMSM drive during starting
- 29. control circuit for Dc/Dc to converter.
- 30. control circuit for Speed control of the motor
- 31. Wave forms
- 32. PMSM drive under change in solar irradiation
- 33. Wave forms
- 34. proposed converter with constant irradiation
- 35. Constant Irradiation for PV Cell.
- 36. Wave forms
- 37. Extension Grid connected mode • The solar PV system is used to transfer the power to the grid, when motor is off.. The controller must act to maintain the DC bus voltage constant as possible and improve the stability of the whole system.
- 38. Extension Grid connected mode • Output voltage waveform of Grid interface inverter
- 39. output waveform of active and reactive power Injection to grid
- 40. CONCLUSION • A stand alone solar PV system has been modelled for the PMSM drive used in water pumping system. Solar PV water-pumping systems are simple, reliable, conserve energy and need less maintenance. It has been demonstrated that proposed system provide satisfactory control on motor speed for water pumping under wide change in solar irradiation.