Modeling and Simulation of Hybrid Wind Solar Energy System using MPPT

ABSTRACT:

The main objective of this paper is to enhance the power transfer capability of grid interfaced hybrid generation system. Generally, this hybrid system is a combination of solar and wind energy systems. In order to get maximum and constant output power from these renewable energy systems at any instant of time, this paper proposes the concept of maximum power tracking techniques. The main concept of this maximum power point tracking controller is used for controlling the Direct Current (DC) to DC boost converter. Finally, the performance of this Maximum Power Point Tracking (MPPT) based Hybrid system is observed by simulating using Matlab/Simulink.

KEYWORDS: MPPT Technique, Solar Energy System, Wind Turbine System

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

image001

Figure 1. Configuration of Hybrid Energy System.

EXPECTED SIMULATION RESULTS:

 image002

Figure 2. Simulation Diagram for Hybrid Wind-PV System.

image003

Figure 3. Output Load Voltage.

image004

Figure 4. Output Load Current.

image005

Figure 5. Powers: Line, Wind, Solar.

image006

Figure 6. Output Voltage from Wind System.

image007

Figure 7. Output Voltage from Wind System.

 CONCLUSION:

Output from solar and a wind system is converted into AC power output by using inverter. In the given time additional load of 5 KW is connected by using Circuit Breaker. Under all operating conditions to meet the load the hybrid system is controlled to give maximum output power. Battery is supporting to wind or solar system to meet the load and Also, simultaneous operation for the same load.

REFERENCES:

  1. Huil J, Bakhshai A, Jain PK. A hybrid wind-solar energy system: A new rectifier stage topology. 2010 25th Annual IEEE Proceedings of Applied Power Electronics Conference and Exposition (APEC); 2010 Feb 21–25. p. 156–61.
  2. Kim SK, Jeon JH, Cho CH, Ahn JB, Kwon SH. Dynamic modeling and control of a grid-connected hybrid genera­tion system with versatile power transfer. IEEE Transactions on Industrial Electronics. 2008 Apr; 55(4):1677–88.
  3. Ezhilarasan S, Palanivel P, Sambath S. Design and devel­opment of energy management system for DG source allocation in a micro grid with energy storage system. Indian Journal of Science and Technology. 2015 Jun; 8(13):58252.
  4. Patel MR. Wind and solar power systems design analysis and operation. 2nd ed. Taylor and Francis Group Publishing Co. 2006; 30(3):265–6.
  5. Chen YM, Liu YC, Hung SC, Cheng CS. Multi-input inverter for grid-connected hybrid PV/wind power system. IEEE Transactions on Power Electronics. 2007 May; 22(3):1070–7.

 

Digital Simulation of the Generalized Unified Power Flow Controller System with 60-Pulse GTO-Based Voltage Source Converter

 

ABSTRACT:

The Generalized Unified Power Flow Controller (GUPFC) is a Voltage Source Converter (VSC) based Flexible AC Transmission System (FACTS) controller for shunt and series compensation among the multiline transmission systems of a substation. The paper proposes a full model comprising of 60-pulse Gate Turn-Off thyristor VSC that is constructed becomes the GUPFC in digital simulation system and investigates the dynamic operation of control scheme for shunt and two series VSC for active and reactive power compensation and voltage stabilization of the electric grid network. The complete digital simulation of the shunt VSC operating as a Static Synchronous Compensator (STATCOM) controlling voltage at bus and two series VSC operating as a Static Synchronous Series Capacitor (SSSC) controlling injected voltage, while keeping injected voltage in quadrature with current within the power system is performed in the MATLAB/Simulink environment using the Power System Block set (PSB). The GUPFC, control system scheme and the electric grid network are modeled by specific electric blocks from the power system block set. The controllers for the shunt VSC and two series VSCs are presented in this paper based on the decoupled current control strategy. The performance of GUPFC scheme connected to the 500-kV grid is evaluated. The proposed GUPFC controller scheme is fully validated by digital simulation.

KEYWORDS:

60-Pulse GTO Thyristor Model VSC, UPFC, GUPFC,Active and Reactive Compensation, Voltage Stability

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

UPFC with 60-Pulse GTO-Based Voltage Source Converter

Figure 1. Three-bus system with the GUPFC at bus B5 and B2

EXPECTED SIMULATION RESULTS:

2

 Figure 2. Sixty-pulse VSC output voltage

3

Figure 3. Simulated results of the GUPFC .shunt converter operation for DC voltage with Qref = 0.3pu; 0.5 pu

4

Figure 4. Simulated results of the GUPFC series converter operation Pref=8.7pu; 10pu, Qref=-0.6pu; 0.7pu

5

Figure 5. Simulated results of the GUPFC series converter operation Pref=7.7pu; 9.0pu, Qref=-0.5pu; 0.9pu

6

Figure 6. Digital simulation results for the decoupled current controller schemes for the shunt VSC in a weak power system

 CONCLUSION:

The paper presents and proposes a novel full 60-pulse GTO voltage source converter that it constructed becomes GUPFC FACTS devices. It comprises the full 60-pulse VSC-cascade models connected to the grid network through the coupling transformer. These full descriptive digital models are validated for voltage stabilization, active and reactive compensation and dynamically power flow control using three decoupled current control strategies. The control strategies implement decoupled current control switching technique to ensure accountability, minimum oscillatory behavior, minimum inherent phase locked loop time delay as well as system instability reduced impact due to a weak interconnected ac system and ensures full dynamic regulation of the bus voltage (VB), the series voltage injected and the dc link voltage Vdc. The 60-pulse VSC generates less harmonic distortion and reduces power quality problems in comparison to other converters such as (6,12,24 and 36) pulse. In the synchronous reference frame, a complete model of a GUPFC has been presented and control circuits for the shunt and two series converters have been described. The simulated results presented confirm that the performance of the proposed GUPFC is satisfactory for active and reactive power flow control and independent shunt reactive compensation.

 REFERENCES:

[1] K. K. Sen, “SSSC-static synchronous series compensator. Theory, modeling and application”, IEEE Transactions on Power Delivery, Vol. 13, No. 1, pp. 241-246, January 1998.

[2] B. Fardanesh, B. Shperling, E. Uzunovic, and S. Zelingher, “Multi-Converter FACTS Devices: The Generalized Unified Power Flow Controller (GUPFC),” in IEEE 2000 PES Summer Meeting, Seattle, USA, July 2000.

[3] N. G. Hingorani and L. Gyugyi, “Understanding FACTS, Concepts and Technology of Flexible AC Transmission Systems. Pscataway, NJ: IEEE Press. 2000.

[4] X. P. Zang, “Advanced Modeling of the Multicontrol Func-tional Static Synchronous Series Compensator (SSSC) in Newton Power Flow” , IEEE Transactions on Power Systems, Vol. 20, No. 4, pp. 1410-1416, November 2005,

[5] A. H. Norouzi and A. M. Sharaf, Two Control Schemes to Enhance the Dynamic Performance of the Statcom and Sssc”, IEEE Transactions on Power Delivery, Vol. 20, No. 1, pp. 435-442, January 2005.

 

 

A Two-Level, 48-Pulse Voltage Source Converter for HVDC Systems

ABSTRACT

This paper deals with an analysis, modeling and control of a two level 48-pulse voltage source converter for High Voltage DC (HVDC) system. A set of two-level 6-pulse voltage source converters (VSCs) is used to form a 48-pulse converter operated at fundamental frequency switching (FFS). The performance of the VSC system is improved in terms of reduced harmonics level at FFS and THD (Total Harmonic Distribution) of voltage and current is achieved within the IEEE 519 standard. The performance of the VSC is studied in terms of required reactive power compensation, improved power factor and reduced harmonics distortion. Simulation results are presented for the designed two level multipulse converter to demonstrate its capability. The control algorithm is disused in detail for operating the converter at fundamental frequency switching.

 KEYWORDS

Two-Level Voltage Source Converter

HVDC Systems

Multipulse

Fundamental Frequency Switching

Harmonics.

 SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

1

Fig. 1 A 48-Pulse voltage source converter based HVDC system configuration

 EXPECTED SIMULATION RESULTS:

2

Fig. 2 Steady state performance of proposed 48-pulse voltage source converter

3 4

Fig. 3 Dynamic performance of proposed 48-pulse voltage source converter

 5 6

 Fig. 4 Waveforms and harmonic spectra of 48-pulse converter (a) supply voltage (b) supply current (c) converter voltage

 CONCLUSION

A 48-pulse two-level voltage source converter has been designed, modeled and controlled for back-to-back HVDC system. The transformer connections with appropriate phase shift have been used to realize a 48-pulse converter along with a control scheme using a set of two level six pulse converters. The operation of the designed converter configuration has been simulated and tested in steady sate and transient conditions which have demonstrated the quite satisfactory converter operation. The characteristic harmonics of the system has also improved by the proposed converter configuration.

 REFERENCES

[1] J. Arrillaga, Y. H. Liu and N. R. Waston, “Flexible Power Transmission, The HVDC Options,” John Wiley & Sons, Ltd, Chichester, UK, 2007.

[2] Gunnar Asplund Kjell Eriksson and kjell Svensson, “DC Transmission based on Voltage Source Converter,” in Proc. of CIGRE SC14 Colloquium in South Africa 1997, pp.1-8.

[3] Y. H. Liu R. H. Zhang, J. Arrillaga and N. R. Watson, “An Overview of Self-Commutating Converters and their Application in Transmission and Distribution,” in Conf. IEEE/PES Trans. and Distr.Conf. & Exhibition, Asia and Pacific Dalian, China 2005.

[4] B. R. Anderson, L. Xu, P. Horton and P. Cartwright, “Topology for VSC Transmission,” IEE Power Engineering Journal, vol.16, no.3, pp142- 150, June 2002.

[5] G. D. Breuer and R. L. Hauth, “HVDC’s Increasing Poppularity”, IEEE Potentials, pp.18-21, May 1988.

A Two-Level 24-Pulse Voltage Source Converter with Fundamental Frequency Switching for HVDC System

 ABSTRACT

This paper manages the execution investigation of a two-level, 24-beat Voltage Source Converters (VSCs) for High Voltage DC (HVDC) framework for power quality enhancement. A two dimension VSC is utilized to understand a 24-beat converter with least exchanging misfortune by working it at fundamental recurrence exchanging (FFS). The execution of this converter is contemplated on different issues, for example, consistent state activity, dynamic conduct, responsive power pay, control factor amendment, and sounds mutilation. Reproduction results are exhibited for a two dimension 24-beat converter to show its ability.

 BLOCK DIAGRAM:

 1

 Fig. 1 A 24-Pulse voltage source converter based HVDC system Configuration

EXPECTED SIMULATION RESULTS

 2

Fig. 2 Synthesis of Stepped AC voltage waveform of 24-pulse VSC.

 

3

Fig. 3 Steady state performance of proposed 24-pulse voltage source Converter

4

Fig. 4 Dynamic performance of proposed 24-pulse voltage source converter

 

5

Fig. 5 Waveforms and harmonic spectra of 24-pulse covnerter i) supply voltage ii) supply current (iii) converter voltage

CONCLUSION

A two dimension, 24-beat voltage source converter has been structured and its execution has been approved for HVDC framework to enhance the power quality with major recurrence exchanging. Four indistinguishable transformers have been utilized for stage move and to understand a 24-beat converter alongside control conspire utilizing a two dimension voltage source converter topology. The enduring state and dynamic execution of the planned converter setup has been exhibited the very attractive task and found appropriate for HVDC framework. The trademark sounds of the converter framework has likewise enhanced by the proposed converter design with least exchanging misfortunes without utilizing additional sifting necessities contrasted with the ordinary 12-beat thyristor converter.

 

 

A New Control Strategy for Active and Reactive Power Control of Three-Level VSC Based HVDC System

ABSTRACT

This paper displays another control procedure no doubt and receptive power control of three-level multipulse voltage source converter based High Voltage DC (HVDC) transmission framework working at Fundamental Frequency Switching (FFS). A three-level voltage source converter replaces the regular two-level VSC and it is intended for the genuine and responsive power control is each of the four quadrants task. Another control strategy is produced for accomplishing the receptive power control by changing the beat width and by keeping the dc connect voltage consistent. The enduring state and dynamic exhibitions of HVDC framework interconnecting two unique frequencies arrange are shown for dynamic and responsive forces control. Complete quantities of transformers utilized in the framework are decreased in contrast with two dimension VSCs. The execution of the HVDC framework is likewise enhanced as far as decreased music level even at essential recurrence exchanging.

 

BLOCK DIAGRAM: 1

Fig. 1 A three-level 24-Pulse voltage source converter based HVDC system

 CONTROL SCHEME

2

Fig. 2 Control scheme of three-level VSC based HVDC system using dynamic dead angle (β) Control

EXPECTED SIMULATION RESULTS

3

Fig. 3 Performance of rectifier station during simultaneous real and reactive power control of three-level 24-pulse VSC based HVDC system

4

Fig. 4 Performance of inverter station during simultaneous real and reactive power control of three-level 24-pulse VSC based HVDC system

5

Fig. 5 Variation of angles (δ) and (β) values of three-level 24-pulse VSC based HVDC system during simultaneous real and reactive power control

CONCLUSION

Another control technique for three-level 24-beat voltage source converter setup has been intended for HVDC framework. The execution of this 24-beat VSC based HVDC framework utilizing the control technique has been exhibited in dynamic power control in bidirectional, free control of the receptive power and power quality enhancement. Another powerful dead point (β) control has been presented for three-level voltage source converter working at crucial recurrence exchanging. In this control the HVDC framework activity is effectively exhibited and furthermore an examination of (β) esteem for different responsive power necessity and symphonious execution has been completed in detail. In this way, the determination of converter task locale is progressively adaptable as indicated by the necessity of the responsive power and power quality.

A Novel High StepUp DC DC Converter Based on Integrating Coupled Inductor and Switched-Capacitor Techniques for Renewable Energy Applications

ABSTRACT

In this paper, a novel high development up dc/dc converter is shown for maintainable power source applications. The proposed structure involves a coupled inductor and two voltage multiplier cells, in order to get high development up voltage gain. Likewise, two capacitors are charged in the midst of the kill time frame, using the essentialness set away in the coupled inductor which manufactures the voltage trade gain. The essentialness set away in the spillage inductance is reused with the use of a dormant fasten circuit. The voltage load on the basic power switch is furthermore diminished in the proposed topology. Thusly, a key influence switch with low resistance RDS(ON) can be used to diminish the conduction incidents. The action rule and the tireless state examinations are discussed inside and out. To check the execution of the showed converter, a 300-W lab demonstrate circuit is completed. The results affirm the speculative examinations and the practicability of the showed high development up converter.

 CIRCUIT DIAGRAM:

image017

Fig. 1. Circuit configuration of the presented high-step-up converter.

SIMULATION RESULTS:

 image018 image019 image020 image021 image022 image023 image024

Fig. 2. Simulation results under load 300 W.

 CONCLUSION

This paper demonstrates another high-advance up dc/dc converter for maintainable power source applications. The suggested converter is fitting for DG systems reliant on practical power sources, which require high-advance up voltage trade gain. The essentialness set away in the spillage inductance is reused to upgrade the execution of the showed converter. In addition, voltage load on the essential power switch is diminished. In like manner, a switch with a low on-state obstacle can be picked. The continuing state errand of the converter has been dismembered in detail. Moreover, the limit condition has been procured. Finally, a hardware show is executed which changes over the 40-V input voltage into 400-V yield voltage. The results exhibit the credibility of the presented converter.

A Multi-Input Bridgeless Resonant AC-DC Converter for Electromagnetic Energy Harvesting

ABSTRACT

In this paper, a novel high development up dc/dc converter is shown for reasonable power source applications. The proposed structure includes a coupled inductor and two voltage multiplier cells, in order to get high development up voltage gain. In addition, two capacitors are charged in the midst of the kill time frame, using the essentialness set away in the coupled inductor which assembles the voltage trade gain. The imperativeness set away in the spillage inductance is reused with the usage of an inactive catch circuit. The voltage load on the key power switch is also diminished in the proposed topology. In this manner, an essential influence switch with low restriction RDS(ON) can be used to diminish the conduction adversities. The action rule and the persevering state examinations are discussed by and large. To check the execution of the showed converter, a 300-W lab demonstrate circuit is completed. The results favor the speculative examinations and the practicability of the displayed high development up converter.

 BLOCK DIAGRAM:

image001

image002

Fig. 1. Multi-channel EMR generators and PEI system: (a) conventional PEI; and (b) proposed multi-input PEI.

CIRCUIT DIAGRAM:

image003

Fig. 2. Illustrative scheme of the proposed multi-input converter (v(i)emf: EMF of #i reed; r(i)EMR: coil resistance; L(i)EMR: self-inductance; i(i)EMR: reed terminal current; v(i)EMR: reed terminal voltage; C(i)r1= C(i)r2: resonant capacitors; Lr: resonant inductor; Q(i)r1, Q(i)r2: MOSFETs; Dr: output diode; Co: output capacitor).

EXPERIMENTAL RESULTS:

image004

  •                                                             (a)
  • image005                                                                    (b)

Fig. 3. Experimental waveforms of power amplifiers: fin = 20 Hz; X-axis: 10 ms/div; Y-axis: (a) vemf = 3 Vrms; Ch1 = output voltage (Vo), 2.5 V/div; Ch2 = terminal voltage (vEMR) of reed #1, 10 V/div; Ch3 = input current (iEMR) of six reeds, 50 mA/div; and (b) vemf = 0.5 Vrms; Ch1 = output voltage (Vo), 0.5 V/div; Ch2 = terminal voltage (vEMR) of reed #1, 5 V/div; Ch3 = sum of the input currents (iEMR) of six reeds, 10 mA/div.

 image006                                                         (a)

image007

  •                                                           (b)

Fig. 4. Experimental waveforms of power amplifiers with step change: X-axis: 40 ms/div; Y-axis: (a) vemf = from 1 Vrms to 2 Vrms; Ch1 = output voltage (Vo), 1 V/div; Ch2 = terminal voltage (vEMR) of reed #1, 5 V/div; Ch3 = input current (iEMR) of six reeds, 50 mA/div; and (b) fin = from 20 Hz to 50 Hz; Ch1 = output voltage (Vo), 0.5 V/div; Ch2 = terminal voltage (vEMR) of reed #1, 5 V/div; Ch3 = input current (iEMR) of six reeds, 50 mA/div.

image008

(a)

image009

  •                                                                 (b)

Fig. 5. Experimental waveforms of EMR generators: X-axis: (a) 20 ms/div; (b) 100 ms/div; Y-axis: (a) constant wind speed; (b) wind speed step change; Ch1 = terminal voltage (vEMR) of reed #2, 5 V/div; Ch2 = output voltage (Vo), 1 V/div; Ch3 = terminal voltage (vEMR) of reed #1, 10 V/div; Ch4 = input current (iEMR) of reed #1, 10 mA/div.

 CONCLUSION

In this paper, a novel high advancement up dc/dc converter is appeared sensible power source applications.

The proposed structure incorporates a coupled inductor and two voltage multiplier cells, so as to get high improvement up voltage gain.

Moreover, two capacitors are charged amidst the kill time allotment, utilizing the vitality set away in the coupled inductor which collects the voltage exchange gain.

The significance set away in the spillage inductance is reused with the utilization of an inert catch circuit. The voltage stack on the key power switch is additionally reduced in the proposed topology. As such, a fundamental impact switch with low limitation RDS(ON) can be utilized to lessen the conduction misfortunes. The activity rule and the enduring state examinations are talked about all things considered. To check the execution of the indicated converter, a 300-W lab show circuit is finished. The outcomes support the theoretical examinations and the practicability of the showed high improvement up converter.

High-Efficiency MOSFET Transformerless Inverter for Non-isolated Microinverter Applications

ABSTRACT

Best in class low-control level metal– oxide– semiconductor field-affect transistor (MOSFET)- based transformerless photovoltaic (PV) inverters can achieve high capability by using latest super convergence MOSFETs. In any case, these MOSFET-based inverter topologies encounter the evil impacts of no less than one of these drawbacks: MOSFET disillusionment danger from body diode pivot recovery, extended conduction incidents as a result of more devices, or low magnetics use. By part the conventional MOSFET based stage leg with a streamlined inductor, this paper proposes a novel MOSFET-based stage leg plan to restrict these burdens. In light of the proposed stage leg structure, a high viability single-arrange

MOSFET

MOSFET transformerless inverter is shown for the PV microinverter applications. The pulsewidth change (PWM) direction and circuit undertaking rule are then portrayed. The ordinary mode and differential-mode voltage show is then displayed and analyzed for circuit structure. Exploratory outcomes of a 250Whardware model are seemed to show the advantages of the proposed transformerless inverter on non-isolated two-sort out PV microinverter application.

 BLOCK DIAGRAM:

image001

Fig. 1. Two-stage nonisolated PV microinverter.

CIRCUIT DIAGRAM:

image002

Fig. 2. Proposed transformerless inverter topology with (a) separated magnetic and (b) integrated magnetics.

 EXPERIMENTAL RESULTS:

image003

Fig. 3. Output voltage and current waveforms.

image004

Fig. 4. PWM gate signals waveforms.

image005

Fig. 5. Inverter splitting inductor current waveform.

image006

Fig. 6. Waveforms of voltage between grid ground and DC ground (VEG ).

CONCLUSION

This paper proposes a MOSFET transformerless inverter with a novel MOSFET-based stage leg, which accomplishes:

1) high proficiency by utilizing super intersection MOSFETs and SiC diodes;

2) limited dangers from the MOSFET stage leg by part the MOSFET stage leg with streamlined inductor and limiting the di/dt from MOSFET body diode switch recuperation;

3) high magnetics use contrasted and past high proficiency MOSFET transformerless inverters in [21], [22], [25], which just have half magnetics use.

PWM

The proposed transformerless inverter has no dead-time necessity, basic PWM regulation for usage, and limited high-recurrence CMissue. A 250W hardware model has been planned, created, and tried in two-arrange nonisolated microinverter application. Exploratory outcomes exhibit that the proposed MOSFET transformerless inverter accomplishes 99.01% pinnacle effectiveness at full load condition and 98.8% CEC productivity and furthermore accomplishes around 98% attractive use. Because of the benefits of high effectiveness, low CM voltage, and enhanced attractive use, the proposed topology is alluring for two-organize nonisolated PV microinverter applications and transformerless string inverter applications.

 

A High Step-Up DC to DC Converter Under Alternating Phase Shift Control for Fuel Cell Power System

ABSTRACT

This paper researches a novel pulse width modulation (PWM) conspire for two-stage interleaved support converter with voltage multiplier for energy component control framework by consolidating substituting stage move (APS) control and conventional interleaving PWM control. The APS control is utilized to lessen the voltage weight on switches in light load while the customary interleaving control is utilized to keep better execution in substantial load. The limit condition for swapping among APS and conventional interleaving PWM control is inferred. In light of the previously mentioned examination, a full power run control joining APS and conventional interleaving control is proposed. Misfortune breakdown examination is likewise given to investigate the productivity of the converter. At long last, it is confirmed by test results.

BLOCK DIAGRAM:

image001

Fig. 1. Grid-connected power system based on fuel cell.

image002

Fig. 2. Main theoretical waveforms at boundary condition.

EXPERIMENTAL RESULTS:

 image003image004 image005 image006Fig.3 Experimental results at boundary condition with traditional interleaving control (L = 1158 μH, R = 2023 Ω, and D = 0.448). (a) CH1-S1 Driver Voltage, CH2 L1 Current, CH3-S1 Voltage Stress, CH4-Output Voltage, (b) CH1-S1 Driver Voltage, CH2 C1 Current, CH3-S1 Voltage Stress, CH4-OutputVoltage, (c) CH1-S1 DriverVoltage,CH2 D1 Current,CH3-S1 Voltage Stress, CH4-Output Voltage, (d) CH1-S1 Driver Voltage, CH2 DM1 Current, CH3-S1 Voltage Stress, CH4-Output Voltage.

image007

Fig. 4. Traditional interleaving control at nominal load (L = 1158 μH and R = 478 Ω).]

image008

Fig. 5. Traditional interleaving control in Zone A (L = 1158 μH and R = 1658 Ω).

CONCLUSION

The limit condition is determined after stage investigation in this paper. The limit condition arranges the working states into two zones, i.e., Zone An and Zone B. The conventional interleaving control is utilized in Zone A while APS control is utilized in Zone B. What’s more, the swapping capacity is accomplished by a rationale unit. With the proposed control plot, the converter can accomplish low voltage weight on switches in all power scope of the heap, which is confirmed by exploratory outcomes.

A High Step-Up Converter with Voltage-Multiplier Modules for Sustainable Energy Applications

ABSTRACT

This paper proposes a novel isolated high step-up converter for sustainable energy applications. Through an adjustable voltage-multiplier module, the proposed converter achieves a high step-up gain without utilizing either a large duty ratio or a high turns ratio. The voltage-multiplier modules are composed of coupled inductors and switched capacitors. Due to the passive lossless clamped performance, leakage energy is recycled, which alleviates a large voltage spike across the main switches and improves efficiency. Thus, power switches with low levels of voltage stress can be adopted for reducing conduction losses. In addition, the isolated topology of the proposed converter satisfies electrical-isolation and safety regulations. The proposed converter also possesses continuous and smooth input current, which decreases the conduction losses, lengthens life time of the input source, and constrains conducted electromagnetic-interference problems. Finally, a prototype circuit with 40 V input voltage, 380 V output, and 500 W maximum output power is operated to verify its performance. The maximum efficiency is 94.71 % at 200 W, and the full-load efficiency is 90.67 % at 500 W.

 KEYWORDS

  1. High Step-Up
  2. Voltage-Multiplier Module
  3. Isolated Converter

SOFTWARE: MATLAB/SIMULINK

BLOCK DIAGRAM:

image001

Fig. 1. Block diagram of a typically sustainable energy system.

CIRCUIT DIAGRAM:

image002

Fig. 2. Proposed isolated high step-up converter for sustainable e
nergy applications.

EXPERIMENTAL RESULTS:

image003

(a) Measured waveforms of vDS1, vDS2, iLin and iLk

image004

(b) Measured waveforms of vDc, vDr and iDr

image005

(C)Measured waveforms of vDf1, vDf2, iDf1 and iDf2

image006

(d) Measured waveforms of vDo, iDo and Vo

Fig.3 The experimental waveforms measured at a full load of 500 W.

CONCLUSION

This paper has presented the theoretical analysis of steady-state and experimental results for the proposed converter, which successfully demonstrates its performance. A prototype isolated converter has been successfully implemented with a high step-up ratio and high efficiency for sustainable energy applications. The presented circuit topology inherently makes the input current continuous and smooth, which decreases the conduction losses, lengthens the life time of the input source, and constrains conducted EMI problems. In addition, the lossless passive clamp function recycles the leakage energy and constrains/lowers the voltage spikes across the power switches. Meanwhile, the voltage stress on the power switch is restricted and is much lower than the output voltage Vo, which is 380 V. Furthermore, the full-load efficiency is 90.67% at Po =500 W, and the maximum efficiency is 94.71% at Po = 200 W. Thus, the proposed converter is suitable for renewable-energy applications that need high step-up conversion and have electrical-isolation requirements.

 REFERENCES

  1. Kefalas, and A. Kladas, “Analysis of transformers working under heavily saturated conditions in grid-connected renewable energy systems,” IEEE Trans. Ind. Electron., vol. 59, no. 5, pp. 2342–2350, May 2012

2. Jonghoon Kim, Jaemoon Lee, and B. H. Cho, “Equivalent circuit modeling of pem fuel cell degradation combined with a lfRC,” IEEE Trans. Ind. Electron., vol. 60, no. 11, pp. 5086–5094, Nov. 2013.

3. Prasanna U R, and Akshay K. Rathore, “Extended range zvs active-clamped current-fed full-bridge isolated dc/dc converter for fuel cell applications: analysis, design, and experimental results,” IEEE Trans. Ind. Electron., vol. 60, no. 7, pp. 2661–2672, July 2013.

4. Shih-Jen Cheng, Yu-Kang Lo, Huang-Jen Chiu, and Shu-Wei Kuo, “High-efficiency digital-controlled interleaved power converter for high-power pem fuel-cell applications,” IEEE Trans. Ind. Electron., vol. 60, no. 2, pp. 773–780, Feb. 2013.

5. Changzheng Zhang, Shaowu Du, and Qiaofu Chen, “A novel scheme suitable for high-voltage and large-capacity photovoltaic power stations,” IEEE Trans. Ind. Electron., vol. 60, no. 9, pp. 3775–3783, Sept. 2013.