BLDC Motor Driven Solar PV Array Fed WaterPumping System Employing Zeta Converter

 ABSTRACT:

This paper proposes a solar photovoltaic (SPV) array fed water pumping system utilizing a zeta converter as an intermediate DC-DC converter in order to extract the maximum available power from the SPV array. Controlling the zeta converter in an intelligent manner through the incremental conductance maximum power point tracking (INC-MPPT) algorithm offers the soft starting of the brushless DC (BLDC) motor employed to drive a centrifugal water pump coupled to its shaft. Soft starting i.e. the reduced current starting inhibits the harmful effect of the high starting current on the windings of the BLDC motor. A fundamental frequency switching of the voltage source inverter (VSI) is accomplished by the electronic commutation of the BLDC motor, thereby avoiding the VSI losses occurred owing to the high frequency switching. A new design approach for the low valued DC link capacitor of VSI is proposed. The proposed water pumping system is designed and modeled such that the performance is not affected even under the dynamic conditions. Suitability of the proposed system under dynamic conditions is demonstrated by the simulation results using MATLAB/Simulink software.

KEYWORDS:

1.      SPV array

2.      Zeta converter

3.      INC-MPPT

4.      BLDC motor

5.       Electronic commutation

SOFTWARE: MATLAB/SIMULINK

CIRCUIT DIAGRAM:

Fig.1 Configuration of proposed SPV array-Zeta converter fed BLDC motor drive for water pumping system.

EXPECTED SIMULATION RESULTS:

Fig.2 Performances of the proposed SPV array based Zeta converter fed BLDC motor drive for water pumping system (a) SPV array variables, (b) Zeta converter variables, and (c) BLDC motor-pump variables.

CONCLUSION:

The SPV array-zeta converter fed VSI-BLDC motor-pump for water pumping has been proposed and its suitability has been demonstrated by simulated results using MATLAB/Simulink and its sim-power-system toolbox. First, the proposed system has been designed logically to fulfil the various desired objectives and then modelled and simulated to examine the various performances under starting, dynamic and steady state conditions. The performance evaluation has justified the combination of zeta converter and BLDC motor drive for SPV array based water pumping. The system under study availed the various desired functions such as MPP extraction of the SPV array, soft starting of the BLDC motor, fundamental frequency switching of the VSI resulting in a reduced switching losses, reduced stress on IGBT switch and the components of zeta converter by operating it in continuous conduction mode and stable operation. Moreover, the proposed system has operated successfully even under the minimum solar irradiance.

REFERENCES:

[1] M. Uno and A. Kukita, “Single-Switch Voltage Equalizer Using Multi- Stacked Buck-Boost Converters for Partially-Shaded Photovoltaic Modules,” IEEE Transactions on Power Electronics, no. 99, 2014.

[2] R. Arulmurugan and N. Suthanthiravanitha, “Model and Design of A Fuzzy-Based Hopfield NN Tracking Controller for Standalone PV Applications,” Electr. Power Syst. Res. (2014). Available: http://dx.doi.org/10.1016/j.epsr.2014.05.007

[3] S. Satapathy, K.M. Dash and B.C. Babu, “Variable Step Size MPPT Algorithm for Photo Voltaic Array Using Zeta Converter – A Comparative Analysis,” Students Conference on Engineering and Systems (SCES), pp.1-6, 12-14 April 2013.

[4] A. Trejos, C.A. Ramos-Paja and S. Serna, “Compensation of DC-Link Voltage Oscillations in Grid-Connected PV Systems Based on High Order DC/DC Converters,” IEEE International Symposium on Alternative Energies and Energy Quality (SIFAE), pp.1-6, 25-26 Oct. 2012.

[5] G. K. Dubey, Fundamentals of Electrical Drives, 2nd ed. New Delhi, India: Narosa Publishing House Pvt. Ltd., 2009.

Direct Torque Control using Switching Table for Induction Motor Fed by Quasi Z-Source Inverter

ABSTRACT:

Z-source inverters eliminate the need for front-end DC-DC boost converters in applications with limited DC voltage such as solar PV, fuel cell. Quasi Z-source inverters offer advantages over Z-source inverter, such as continuous source current and lower component ratings. In this paper, switching table based Direct Torque Control (DTC) of induction motor fed by quasi Z-Source Inverter (qZSI) is presented. In the proposed technique, dc link voltage is boosted by incorporating shoot through state into the switching table. This simplifies the implementation of DTC using qZSI. An additional DC link voltage hysteresis controller is included along with torque and flux hysteresis controllers used in conventional DTC. The results validate the boost capability of qZSI and torque response of the DTC.

KEYWORDS:

1.      DTC

2.      QZSI

3.      DC-DC Converter

4.      DC Link Voltage

5.      Hysteresis Controller

SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

Fig. 1: Block Diagram for DTC using qZSI

EXPECTED SIMULATION RESULTS:

Fig.2: Torque vs. Time

Fig. 3: Stator Phase 'a' Current

Fig. 4: Speed vs. Time

Fig. 5: DC Link Voltage

Fig. 6: Capacitor Voltage, VC1

CONCLUSION:

In this paper, direct torque control of induction motor fed by qZSI is presented. Dynamic torque response for step change obtained is 3 ms, which is needed for high performance applications. qZSI provides a single stage solution for drives with variable input DC voItage, instead of DC-DC converter cascaded with 3-leg inverter bridge. This paper presents a solution for drives with lesser DC input voItage availability and also requiring very fast torque response. The results shows that by introducing shoot through state in switching table of direct torque control, DC link voItage in qZSI is boosted. The DC link voItage hysteresis controller uses the input and capacitor voItage for controlling DC link voItage. If there is any disturbance in input voItage, the reference for capacitor voItage will be changed accordingly to maintain the DC link voItage.

 REFERENCES:

[I] 1. Takahashi and Y. Ohmori, "High-performance direct torque control of an induction motor, " IEEE Trans. Ind. Appl., vol. 25, no. 2, pp. 257-264, 1989.

[2] B.-S. Lee and R. Krishnan, "Adaptive stator resistance compensator for high performance direct torque controlled induction motor drives, " in Industry Applications Conference, 1998. Thirty-Third lAS Annual Meeting. The 1998 IEEE, vol. I, Oct 1998, pp. 423-430 voLl.

[3] G. Buja and M. Kazmierkowski, "Direct torque control of pwm inverter-fed ac motors-a survey, " IEEE Trans. Ind. Electron., vol. 51, no. 4, pp. 744-757, Aug 2004.

[4] F. Z. Peng, "Z-source inverter, " IEEE Trans. Ind. Appl., vol. 39, no. 2, pp. 504-510, Mar 2003.

[5] F. Z. Peng, A. Joseph, J. Wang, M. Shen, L. Chen, Z. Pan, E. Ortiz-Rivera, and Y. Huang, "Z-source inverter for motor drives, " IEEE Trans. Power Electron., vol. 20, no. 4, pp. 857-863, July2005.

Solar Power Based Two Level Inverter Fed DTFCSVM of a Sensorless IM Drive

ABSTRACT:

This paper presents a solar power based two level inverter fed sensorless induction motor drive (SIMD) with space vector modulation based direct torque and flux control (DTFCSVM) for the water pumping applications. Due to the robustness and the flexible operating characteristics, induction motor is most suitable for water pump system. The back emf based model reference adaptive system (MRAS) is used to estimate the speed of the motor. This sensorless MRAS based speed estimation technique is independent to the changes in the temperature and it makes the system simple, robust and economic. Moreover, it reduces the complexity while implementing the hardware setup. DC/DC boost converter along with perturb and observe method of maximum power point tracking (MPPT) control technique is employed to draw sophisticated power from the solar photovoltaic (PV) array. The DTFC-SVM of an IMD using basic two level inverter is proposed for water pumping application. The proposed method is simulated in MATLAB/SIMULINK environment and simulated results are presented under various operating conditions.     

KEYWORDS:

1.      Direct torque and flux control

2.      Sensorless induction motor drive

3.      Space vector modulation

4.      Photovoltaic array

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

Fig. 1. Schematic model of DTFC-SVM of sensorless IMD

EXPECTED SIMULATION RESULTS:

Fig.2. Results under no-load torque operating condition using basic two level

inverter: Plot (from top to bottom): (i) Torque, (ii) stator current, (iii) speed,

(iv)stator flux qd-components in stationary reference frame.

Fig.3. Loading performance at 1400rpm using basic two level inverter: (i)

Torque, (ii) speed, (iii) stator current and (iv) error speed,(v) error speed

between actual and estimated speed of motor,(vi) stator fluxes.

Fig.4. Reversal speed Performance using basic two level inverter: (i) Torque,

(ii) speed, (iii) stator current and (iv) stator flux qd-components.

CONCLUSION:

It has been concluded that the solar power based basic two level inverter fed sensorless induction motor drive with DTFC-SVM using proportional-integral controller (PIC) is simple,robust,reduces the complexity while desgningthe hard ware setup hence it is quite suitable for the water pumping applications. The solar panel has been operated at the peak values of voltage, current and power by using a simple perturb and observe method of MPPT algorithm, and the required DC output voltage achieved by using DC/DC boost converter. From the simulation results we can conclude that the basic two level-SVM based sensorless IM drives can provide good performance and less ripple content in torque , fluxes.

REFERENCES:

[1] G. S Buja and Kazmierkowski. M. P, “DTC of pwm inverter-fed AC motors – A Survey”, IEEE Trans. on Ind. Elec., vol. 54, no. 5, pp. 744 – 757, 2004.

[2] J. Rodriguez, J. S. Lai, and F. Z. Peng, “Multilevel inverters: a survey of topologies, controls, and applications,” IEEE Trans. Ind. Electron., vol.49, no.4, pp.724-738, 2002.

[3] Tejavathu Ramesh, Anup Kumar Panda, and S. Shiva Kumar. "MRAS Speed Estimator Based on Type-1 and Type-2 Fuzzy Logic Controller for the Speed Sensorless DTFC-SVPWM of an Induction Motor Drive." Journal of Power Electr., vol. 15, No. 3, pp. 730-740, 2015.

[4] Shukla, Saurabh, and Bhim Singh. "MRAS based speed estimation of single stage solar powered vector controlled induction motor drive for water pumping." Power India International Conference (PIICON), 2016 IEEE 7th. IEEE, 2016.

[5] Shukla, Saurabh, and Bhim Singh. "Single Stage PV Array Fed Speed Sensorless Vector Control of Induction Motor Drive for Water Pumping." IEEE Transactions on Industry Applications (2018).

Single Stage PV System based Direct Torque Controlled PMSM Drive for Pump Load Application

ABSTRACT:

This paper presents design and modelling of single stage standalone PV based PMSM (Permanent Magnet Synchronous Motor) drive. Standalone power supply system is more feasible and convenient option for water pumping applications in irrigation. Three phase DTC (Direct Torque Control) VSI (Voltage Source Inverter) is presented for supplying the PMSM for variation in solar irradiation to control the flow of water in pumping application. MATLAB/SIMULINK environment is used for modeled the proposed single stage standalone PV system based PMSM drive and performance is investigated under change in solar irradiation.

 KEYWORDS:

1.      Direct Torque Control

2.      PMSM Drive

3.      Solar PV

4.      Water Discharge System

 SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

Fig. 1 System configuration of Single stage sensor less standalone solar PV based PMSM drive.

 EXPECTED SIMULATION RESULTS:

Fig.2 Steady state performance for single stage standalone PV based permanent magnet synchronous motor drive

Fig.3 Transient performance under change in irradiation

CONCLUSION:

A single stage off-grid solar photo voltaic system has been modeled using the PMSM employed for centrifugal pump load application. The proposed single stage standalone PV system reduces component count, eliminates intermediate power conversion stage and achieves high conversion efficiency for pumping application. The proposed single stage system gives adequate control on PMSM speed under wide variation in solar irradiation and employing DTC control using three-phase VSl.

REFERENCES:

[1] A. Khaligh and O.C. Onar , Energy harvesting solar, wind, and ocean energy conversion systems, CRC Press, New York, 20 I O.

[2] R. Teodorescu, M. Liserre and P. Rodriguez, Grid Converters for Photovoltaic and Wind Power Systems, I st edition, John Wiley, United Kingdom, 2011.

[3] M. G Villalva, 1. R. Gazoli and E.R. Filho, "Comprehensive Approach to Modeling and Simulation of Photovoltaic Arrays," IEEE Trans. Power Electronics, vol. 24, no. 5, pp. 1198-1208, Mar. 2009.

[4] M. Matsui, T. Kitano, D. H. Xu and Z. Q. Yang, "A new maximum photovoltaic power tracking control scheme based on power equilibrium at dc link," Proc. IEEE Industry Application Con!, Oct. 1999, vol. 2, pp. 804-809.

[5].T. K. Mikihiko and M. De-H. Xu, "Power sensor-less MPPT control scheme utilizing power balance at dc link – system design to ensure stability and response," Proc IEEE IECON Con!, Dec. 200 I, pp. 1309-1314.

A DSP Based Digital Control Strategy for ZVS Bidirectional Buck+Boost Converter

ABSTRACT:

The non-isolated bidirectional DC-DC converters are the most popular topology for low or medium power of the hybrid electric vehicle (HEV) or fuel cell vehicle (FCV) applications. These kinds of converters have the advantages of simple circuit topology, bidirectional flows, zero-voltageswitching (ZVS), high efficiency, and high power density. The turned-on ZVS for all MOSFETs is achieved by the negative offset of the inductor current at the beginning and the end of each switching period. To do this, the converter requires a complex switching strategy which is preferred to be implemented by the digital signal processing (DSP). This paper presents the digital implementation of the switching pattern to ensure the ZVS condition for such converter. A 5kW prototype is performed to verify the capability of such control scheme.

KEYWORDS:

1.      DC-DC converter

2.      Bidirectional converter

3.      Digital control

4.      Phase shift control

SOFTWARE: MATLAB/SIMULINK

 CIRCUIT DIAGRAM:

Fig1. Bidirectional dc dc converter

 EXPECTED SIMULATION RESULTS:

Fig. 2. Inductor current waveforms of (a) boost mode and (b) buck mode

Fig. 3. ZVS turn on of switch S1

Fig. 4. Overall efficiency of both boost and buck operating modes

CONCLUSION:

A DSP based digital control strategy for the bidirectional DC-DC converter is proposed in this paper. The new control strategy provides a negative inductor current at the beginning of each pulse period that, in conjunction with just the parasitic MOSFET output capacitances but no additional components, allows ZVS with the full voltage and load range. The DSP chip TMS320F28035 from Texas Instruments is employed to perform this control algorithm. The experimental results not only show the ZVS for four switches but also provide an excellent overall efficiency at least 96% at the power range.

REFERENCES:

[1] S. S. Williamson, S. M. Lukic, and A. Emadi, “Comprehensive drive train efficiency analysis of hybrid electric and fuel cell vehicles based on motor controller efficiency modeling,” IEEE Trans. Power Electron., vol. 21, no. 3, pp. 730-740, May 2006.

[2] K. Wang, C. Y. Lin, L. Zhu, D. Qu, F. C. Lee, and J. Lai, “Bidirectional dc to dc converters for fuel cell systems,” in Conf. Rec. 1998 IEEE Workshop Power Electronics in Transportation, pp. 47-51.

[3] A. Emadi, S. S. Williamson, and A. Khaligh, “Power electronics intensive solutions for advanced electric, hybrid electric, and fuel cell vehicular power systems,” IEEE Trans. Power Electron., vol. 21, no. 3, pp. 567-577, May 2006.

[4] D. Patel Ankita, “Analysis of bidirectional Buck-Boost converter by using PWM control scheme,” ISSN: 2321-9939, Electronics and Communication, Marwadi Education Foundation Group of Institute, Rajkot, India.

[5] Texas Instruments, “Modeling of bidirectional Buck/Boost converter for digital control using C2000 microcontroller,” Application report SPRABX5, January 2015.