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.

An Improved Control Algorithm of Shunt Active Filter for Voltage Regulation, Harmonic Elimination, Power-Factor Correction, and Balancing of Nonlinear Loads

 ABSTRACT:  

This paper deals with an implementation of a new control algorithm for a three-phase shunt active filter to regulate load terminal voltage, eliminate harmonics, correct supply power-factor, and balance the nonlinear unbalanced loads. A three-phase insulated gate bipolar transistor (IGBT) based current controlled voltage source inverter (CC-VSI) with a dc bus capacitor is used as an active filter (AF). The control algorithm of the AF uses two closed loop PI controllers. The dc bus voltage of the AF and three-phase supply voltages are used as feed back signals in the PI controllers. The control algorithm of the AF provides three-phase reference supply currents. A carrier wave pulse width modulation (PWM) current controller is employed over the reference and sensed supply currents to generate gating pulses of IGBT’s of the AF. Test results are presented and discussed to demonstrate the voltage regulation, harmonic elimination, power-factor correction and load balancing capabilities of the AF system.

KEYWORDS:

1.      Active filter

2.      Harmonic compensation

3.      Load balancing

4.      Power-factor correction

5.      Voltage regulation

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

Fig. 1. Fundamental building block of the active filter.

EXPECTED SIMULATION RESULTS:

Fig. 2. Performance of the AF system under switch IN and steady state conditions with a three-phase nonlinear load.

Fig. 3. Steady state response of the AF for voltage regulation and harmonic elimination with a three-phase nonlinear load.

Fig. 4. Steady state response of the AF for voltage regulation, harmonic elimination, and load balancing with a single-phase nonlinear load.

Fig. 5. Switch IN response of the AF for voltage regulation, harmonic elimination with a three-phase nonlinear load.

Fig. 6. Switch IN response of the AF for voltage regulation, harmonic elimination and load balancing with a single-phase nonlinear load.

Fig. 7. Dynamic response of the AF for voltage regulation, harmonic elimination, and load balancing under the load change from three-phase to single-phase.

Fig. 8. Dynamic response of the AF for voltage regulation, harmonic elimination, and load balancing under the load change from single-phase to three-phase.

Fig. 9. Steady state response of the AF for power-factor correction, harmonic elimination with a three-phase nonlinear load.

Fig. 10. Steady state response of the AF for power-factor correction, harmonic elimination, and load balancing with a single-phase nonlinear load.

Fig. 11. Switch IN response of the AF for power-factor correction and harmonic elimination with a three-phase nonlinear load.

Fig. 12. Switch IN response of the AF for power-factor correction, harmonic elimination, and load balancing with a single-phase nonlinear load.

CONCLUSION:

An improved control algorithm of the AF system has been implemented on a DSP system for voltage regulation/power-factor correction, harmonic elimination and load balancing of nonlinear loads. Dynamic and steady state performances of the AF system have been observed under different operating conditions of the load. The performance of the AF system has been found to be excellent. The AF system has been found capable of improving the power quality, voltage profile, power-factor correction, harmonic elimination and balancing the nonlinear loads. The proposed control algorithm of the AF has an inherent property to provide a self-supporting dc bus and requires less number of current sensors resulting in an over all cost reduction. It has been found that for voltage regulation and power-factor correction to unity are two different things and can not be achieved simultaneously. However, a proper weight-age to in-phase and quadrature components of the supply current can provide a reasonably good level of performance and voltage at PCC can be regulated with a leading power-factor near to unity. It has been found that the AF system reduces harmonics in the voltage at PCC and the supply currents well below the mark of 5% specified in IEEE-519 standard.

REFERENCES:

[1] L. Gyugyi and E. C. Strycula, “Active AC power filters,” in Proc.IEEE-IAS Annu. Meeting Record, 1976, pp. 529–535.

[2] T. J. E. Miller, Reactive Power Control in Electric Systems. Toronto,Ont., Canada: Wiley, 1982.

[3] J. F. Tremayne, “Impedance and phase balancing of main-frequency induction furnaces,” Proc. Inst. Elect. Eng. B, pt. B, vol. 130, no. 3, pp. 161–170, May 1983.

[4] H. Akagi, Y. Kanazawa, and A. Nabae, “Instantaneous reactive power compensators comprising switching devices without energy storage components,” IEEE Trans. Ind. Applicat., vol. IA-20, pp. 625–630, May/June 1984.

[5] T. A. Kneschki, “Control of utility system unbalance caused by single-phase electric traction,” IEEE Trans. Ind. Applicat., vol. IA-21, pp. 1559–1570, Nov./Dec. 1985.