Proteus Based Simulation of PV Inverter for Rural Electrical Service

www.ijmer.com

International Journal of Modern Engineering Research (IJMER) Vol.3, Issue.2, March-April. 2013 pp-1212-1219 ISSN: 2249-6645

Proteus Based Simulation of PV Inverter for Rural Electrical Service Mohammed Shoaib, 1 Prof V. Nagaraj2 1

2

Department Of Electrical &Electronics engineering, Assoc.Prof. (Senior Scale), Manipal Institute of Technology, Manipal University, Manipal, India

Abstract: In many remote or underdeveloped areas, direct access to an electric grid is impossible and a photovoltaic inverter system would make life much simpler and more convenient. With this in mind, this paper aims to design, and simulate PV inverter in proteus professional software. This inverter system could be used as backup power during outages, battery charging, or for typical household applications for rural especially. The principle is to adapt the output voltage of the solar module to the battery by using the technique of pulse width modulation (PWM). The sinusoidal pulse width modulated (PWM) waveform is generated from inverter in laboratory by 16 bit microprocessor through program developed using a novel technique of direct modulation strategy .The key features of the system are a true 50Hz, 230Vsinusoidal voltage output, a wide input range, and a power output of up to 350 watts. The overall goal is to design this system while minimizing component costs.. In addition, inverters in the lower price range typically lack most of the features. solar home lighting systems mostly comprises of solar panel, solar charger, battery & a inverter, The main motivation of this paper or the uniqueness of this project is to combine both the solar charger as well as inverter together to ATMEGA 32 RISC based which works up to 16MIBS which reduces the cost as well as the system becomes compact.

Keywords: Pv, Pwm, Mcu, Proteus, Dpwm, Pwm Charger. I. Introduction India s off-grid solar (PV) market has three major segments: captive power plants (where the majority of generation is consumed at the source), telecom towers, and rural electrification. The market potential for these PV segments has created an off grid solar market in India. India like other developing countries has made tremendous progress in producing energy in agriculture sectors. However, it lags behind in meeting the entire energy demand in remote rural and its nearby suburban or urban areas. As a result, our country is facing acute shortage of power especially in those village areas where utility grids are either not available or its further extension is not possible due to costly affair. Even in the sub-urban or urban area of these villages where utility grids are available, only 20% electricity is available for end users and so they lack such basics of human need as lighting, irrigation, communication, primary health care facility, safe drinking water, education etc. Renewable energy is the only feasible option to electrify these villages and its surrounding areas. Along with increases of demand for the new energy, and the key technologies of use new energy sources is how to integrate new energy into electrical energy. In this paper high computing speed, low-power single chip MCU ATMEGA 32 is used as the control chip, improve the inverter efficiency. This article also describes the structure of the inverter, control methods, focuses on software design and finally summarized. The primary function of a charge controller in a stand-alone PV system is to maintain the battery at highest possible state of charge while protecting it from overcharge by the array and from over discharge by the loads [1]. Although some PV systems can be effectively designed without the use of charge control, any system that has unpredictable loads, user intervention, optimized or undersized battery storage (to minimize initial cost) typically requires a battery charge controller. The algorithm or control strategy of a battery charge controller determines the effectiveness of battery charging and PV array utilization, and ultimately the ability of the system to meet the load demands. Additional features such as temperature compensation, alarms, meters, remote voltage sense loads and special algorithms can enhance the ability of a charge controller to maintain the health and extend the lifetime of a battery, as well as providing an indication of operational status to the system caretaker. Important functions of battery charge controllers and system controls are to [2]:  Prevent Battery Overcharge: to limit the energy supplied to the battery by the PV array when the battery becomes fully charged.  Prevent Battery Over discharge: to disconnect the battery from electrical loads when the battery reaches low state of charge.  Provide Load Control Functions: to automatically connect and disconnect an electrical load at a specified time, for example operating a lighting load from sunset to sunrise.  A series charge controller or series regulator disables further current flow into batteries when they are full. A shunt charge controller or shunt regulator diverts excess electricity to an auxiliary or "shunt" load, such as an electric water heater, when batteries are full.

www.ijmer.com

1212 | Page

www.ijmer.com


Simple charge controllers stop charging a battery when they exceed a set high voltage level, and re-enable charging when battery voltage drops back below that level. Pulse width modulation (PWM) [2] and maximum power point tracker (MPPT) technologies are more electronically sophisticated, adjusting charging rates depending on the battery's level, to allow charging closer to its maximum capacity. Charge controllers may also monitor battery temperature to prevent overheating. Some charge controller systems also display data; transmit data to remote displays, and data logging to track electric flow over time [4].

II. System Block Diagram 2.1Inverter Drive circuit and Filter circuit design.

Figure: 1 ATMega32 microcontroller: It acts as the heart of the system. It controls and monitors entire system. The main function of this microcontroller is to generate SPWM signals. These signals are given to Half-bridge switches to convert dc voltage to ac voltage. Microcontroller also takes care of the protection. It protects the load from over voltage, under voltage.This system includes a feedback network where at the output AC is converted to DC using bridge rectifier and is properly isolated using an npn based opto coupler and a voltage divider circuit which is fed back to adc module of MCU and output voltage is regulated by controlling the duty cycle of the DPWM. In the present work sinusoidal pulse width modulation (SPWM) technique is used to control the switches of the Halfe-bridge. This technique is widely used in inverter to digitize the power so that a sequence of voltage pulses can be generated by the on and off of the power switches. The pulse width modulation inverter has been the main choice in power electronics, because of its circuit simplicity and rugged control scheme. After analysis and comparison, the part of the contra variance use half-bridge inverter circuit, Inverter Bridge is composed of FET IRF3205, using 2n3906 and 2 Bc547 as a driver circuit. Single-chip generated PWM signal, go though 2n3906 to control the inverter switching devices IRF3205 the shutdown of conduction, then inverter can produce sine wave outputs. But the sine wave contains many high-order harmonic generation, required the LC filter circuit to be smooth, nonstandard high-order harmonic generation of sine wave. The size of capacitance and inductance values required theoretical calculations and the actual debugging to determine. In this design, we take C = 100uF, L = 40uH. 2.2 Pwm Control A software program has been developed to generate sinusoidal pulses for N numbers in a half cycle using direct modulation strategy (DPWM) whose widths are proportional to amplitude of sine wave at sampled points (Fig.2). Mathematically the pulse width and corresponding notch width are expressed by (1) and (2) respectively as: Pulse width (Pi) = K Pwm x 2 Sin (2i - 1) π / (2*N) . (1) Where, i = 1, 2, 3,…..N K = Voltage Factor (0 –1) P wm = ( D – G ) * 2 D = 180 / (2*N) G = Minimum Gap between pulses (say 1degree) at K=1 N = Number of PWM pulses in Half sine wave (180 degree i.e. = 10 ms) Notch width (Ti) = 2D - [1/2(Pi – 1 + Pi)]. (2)

www.ijmer.com

1213 | Page

www.ijmer.com


Figure 2: Programmable DPWM sinusoidal Modulated (N = 3 ) half sine wave of 50 Hz . Y axis = Amplitude (5V), X axis = Total time (T) in half cycle i.e 180 degree =10ms.

III. System Software Design 3.1proteus Introduction Proteus supports multiple mainstream microcontroller system simulation, such as 51 series, AVR series, PIC12 PIC16 series, PIC18 series, Z80 series, HC11 series, series, 68,000 series, etc. And provide software debugging function and its periphery connection device of RAM, ROM, keyboard, motor, LED, LCD, AD/DA, partial SPI device. With the development of science and technology, the computer simulation technology has become an important sector of many design method of early. It is designed to be flexible, results, the process of unity. It can make the design time is shortened, cost reduction, also can reduce the risk of engineering. Believe in microcontroller application of PROTEUS can also have extensive application. 3.2Target specifications 3.2.1 Inverter specifications. Frequency Efficiency Output Harmonics spwm Mobility Protection circuits

50 Hz +/- 2Hz >80 % 350 watts, 12VDC ~ 220 V +/- 5 <5 % Sine wave inverter Portable, microcontroller based yes Table1

3.2.2 Solar charge controller specification:  Prevents battery from being overcharged and damaged by the solar panel  Compatible with 12 volt battery bank  Overload, short circuit, and reverse polarity protected.  LED's indicate charging status. 3.3 Simulation Results 3.3.1 pv inverter simulation

Figure 3: (Schematic of Proposed PV Inverter with battery charger.) www.ijmer.com

1214 | Page

www.ijmer.com

International Journal of Modern Engineering Research (IJMER) Vol.3, Issue.2, March-April. 2013 pp-1212-1219 ISSN: 2249-6645 A

B

C

D

E

F

G

H

J

0

K

0

+12

U? 9 13 12

1 2 3 4 5 6 7 8

2

PA0/ADC0 PA1/ADC1 PA2/ADC2 PA3/ADC3 PA4/ADC4 PA5/ADC5 PA6/ADC6 PA7/ADC7 PB0/T0/XCK PB1/T1 PB2/AIN0/INT2 PB3/AIN1/OC0 PB4/SS PB5/MOSI PB6/MISO PB7/SCK

PC0/SCL PC1/SDA PC2/TCK PC3/TMS PC4/TDO PC5/TDI PC6/TOSC1 PC7/TOSC2 PD0/RXD PD1/TXD PD2/INT0 PD3/INT1 PD4/OC1B PD5/OC1A PD6/ICP1 PD7/OC2

AREF AVCC

22 23 24 25 26 27 28 29 14 15 16 17 18 19 20 21

R1

pulse 1 pulse2

12k

+12

+88.8

40 39 38 37 36 35 34 33

XTAL1 XTAL2

AC Volts

1

RESET

Q2

D1

2N3906

1N4007

12k

2N3906

feed back to MCU

2

32 30

TR?

R4

VCC

3

R8

1N4007

R6

TRAN-2P3S

100

ATMEGA32

1

Q3 D?

100

R2

3

R9

12k

12k

LCD? 4

TR?(P1)

M1

LM016L

M1(G)

IRF3205S

4

M2 Q4

D0 D1 D2 D3 D4 D5 D6 D7

RS RW E

VSS VDD VEE

M2(G)

BR1

RA(1)

Q1

R3(1) R3

BC547

R7 IRF3205S

10k

5

1k5

7 8 9 10 11 12 13 14

4 5 6

1 2 3

5

R5 10k

+5

RA

BC547

12k

1K

R10

L1

2W06G VCC

U1

6

L1(2)

1k5

1.2mh

1

RC

6

6

RC(2) v_out

1k

5 2

RB

L?

4

254

230V

OPTOCOUPLER-NPN

RD

7

7

100%

CL1 10u

CD 100uf

1k A

8

8

B C D

9

FILE NAME:

schematic for inverter.DSN

DESIGN TITLE:

3/26/2013 E:\mtech project\mtech\schematic for inverter.DSN 9

PATH:

E:\mtech project\mtech\schematic for inverter.DSN 1 of 1

DATE:

PAGE:

RLCD A

B

C

BY:

D

E

F

G

H

REV:

J

TIME: 11:01:50 PM

K

Fig4. (Schematic of inverter)

Fig5. (Pulse train drawing the mosfet T=20 ms, TON=10ms &TOFF=10ms)

Fig6. (Output voltage waveform as per simulated resultsVO=228 Volts ).

Fig7. (Current wave form as per simulated results IO=1.7 Amps). www.ijmer.com

1215 | Page

www.ijmer.com


3.4 simulation of PWM charge controller A

B

C

D

E

F

G

H

J

K

+5V +5V

FUSE

7805

+5V

LS?

30A

1

R4

LM016L

220

220

+12

D0

C1

C2

47uf

0.1uf

10k

C3 0.1uf

1

LED-GREEN

D2

D0 D1 D2 D3 D4 D5 D6 D7

RS RW E

VSS VDD VEE

3

R1

LED-YELLOW

GND GND

7 8 9 10 11 12 13 14

4 5 6

VO

D3

LED-RED

1 2 3

VI

1N4003

R3 BUZZER

1

0 C3(1) GND

LCD

7805

D1

2

0

Q1

R2

R5

2N2222 1k

1k

Q2

R6

2N2222

1k

GND

Q3

GND

2N2222 GND

2

2

RLCD1 1k

3

3 GND

+12

4

4

ATMEGA32 9 13 12

VCC

Q6

D4

2N3055

D4(K)

40 39 38 37 36 35 34 33

+

5

1N4007

SOLAR TERMINAL 1 2

1 2 3 4 5 6 7 8

Q5

6

2N2222

R7 4.7K

SOLAR POT(3)

RESET

PC0/SCL PC1/SDA PC2/TCK PC3/TMS PC4/TDO PC5/TDI PC6/TOSC1 PC7/TOSC2

XTAL1 XTAL2 PA0/ADC0 PA1/ADC1 PA2/ADC2 PA3/ADC3 PA4/ADC4 PA5/ADC5 PA6/ADC6 PA7/ADC7

PD0/RXD PD1/TXD PD2/INT0 PD3/INT1 PD4/OC1B PD5/OC1A PD6/ICP1 PD7/OC2

PB0/T0/XCK PB1/T1 PB2/AIN0/INT2 PB3/AIN1/OC0 PB4/SS PB5/MOSI PB6/MISO PB7/SCK

RLYS/B

22 23 24 25 26 27 28 29

12V

5

14 15 16 17 18 19 20 21

Q7

RLY S/B

2N2222 1K

6 AREF AVCC

32 30

CENTER TAPPED 1

ATMEGA32

D5

DC CAP(1)

R9 1k

1N4007

C4 SOLAR POT0.1uf

7

7

DUTY POT(2)

15%

10K

DC CAP DUTY POT 1000u

Q4 11%

R8

2N2222

10k

R10

1k

4.7K

8

8 DUTY POT(3)

C5 BATTERY POT 0.1uf

GND

2 1

14%

10K

GND

9

FILE NAME:

schematic.pdf1.DSN

DESIGN TITLE:

3/22/2013 E:\mtech project\mtech\charger3\schematic.pdf1.DSN

PATH:

E:\mtech project\mtech\charger3\schematic.pdf1.DSN 1 of 1

BY:

A

B

C

D

E

DATE:

PAGE:

BATTERY TERMINAL

F

G

H

REV:

J

9

TIME: 10:37:46 AM

K

Figure 8(schematic of pwm based charge controller) Solar Charge controller is a device, which controls the battery charging from solar cell and also controls the battery drain by load. The simple Solar Charge controller checks the battery whether it requires charging and if yes it checks the availability of solar power and starts charging the battery. Whenever controller found that the battery has reached the full charging voltage lavels, it then stops the charging from solar cell. On the other hand, when it found no solar power available then it assumes that it is night time and switch on the load. It keeps on the load until the battery reached to its minimum voltage levels to prevent the battery dip-discharge. Simultaneously Charge controller also gives the indications like battery dip-discharge, load on, charging on etc OPERATION OF SYSTEM: Pulse Width Modulation (PWM) is the most effective means to achieve constant voltage battery charging by switching the solar system controller‟s power devices. When in PWM regulation, the current from the solar array tapers according to the battery‟s condition and recharging needs. In the fig 8 solar charge is controlled by controlling the duty cycle ,such that an optimum 13.75 volts is fed to battery for charging purpose.2N3055 NPN power transistor , Packaged in a TO-3 case style, it is a 15 amp, 60 volt is used as switching device Initially 50 %duty cycle is fed in MCU using PORT C0. As the solar voltage is unregulated the voltage is controlled by adjusting the duty cycle .Two reference voltage is fed in MCU, whenever solar voltage is < reference voltage V1 (>> Pwm), similarly vice versa. 3.4 Simulation Results for PV Charger The proposed charge controller is simulated by using Proreus ISIS 7 Professional for five cases listed in table 1 and the simulation results shown in figures 8-12. Test no 1 2 3 4

Solar voltage 18 16 10 17

Battery voltage 11.0 11.0 12.0 13.5 Table 2

Duty cycle% 96% 99% 35% 0%

3.4.1Algorithm for Charge Controller As microcontroller software works as sequential basis, it will perform these steps Sequentially. 1. Power On, RESET 2. Define Input / Output of the ports 3. Setup ADC for measurement 4. Start ADC Module 5. Measure ADC2, ADC3, ADC4, ADC5. ADC2 for „Solar Voltage‟, ADC3 for „Battery High Set‟, ADC4 for „Battery Low Set‟ and ADC5 for „Battery Voltage‟ 6. If „Battery Voltage‟ < „Battery High Set‟ and „Solar Voltage‟ > „Battery Voltage‟ then www.ijmer.com

1216 | Page

www.ijmer.com


a. Switch ON Battery Charging b. Switch ON Charging LED c. Switch OFF Battery High LED 7. If „Battery Voltage‟ > or = „Battery High Set‟ then a. Switch OFF Battery Charging b. Switch OFF Charging LED c. Switch ON Battery High LED 8. If „Solar Voltage‟ < „Battery Voltage‟ then a. Switch OFF Battery Charging b. Switch OFF Charging LED c. Switch ON Load 9. If „Battery Voltage‟ < or = „Battery Low Set‟ then a. Switch OFF Load b. Switch ON Battery Low LED 10. If „Battery Voltage‟ > „Battery Low Set‟ then a. Switch OFF battery Low LED 11. Go to Step 5.

Figure: 9. (the above schematic refers to step no 6 of the algorithm).

Figure: 10. Simulation Result for Test number 1(channel c represents the output of the MCU PWM signal)

Figure: 11. Simulation Result for Test number 2(channel c represents the output of the MCU PWM signal). www.ijmer.com

1217 | Page

www.ijmer.com


Figure: 12. Simulation Result for Test number 3(channel crepresents the output of the MCU PWM signal)

Figure: 13. Simulation Result for Test number 4(channel crepresents the output of the MCU PWM signal)

Figure13. (The above schematic refers to step no9 of the algorithm)

Figure14. (The above graph shows switching on; of the relay once battery reaches its low set point).

www.ijmer.com

1218 | Page

www.ijmer.com


IV. Conclusion The article is being simulated in the Proteus software, the hardware must be tested accordingly, Proteus not only make many MCU visualize, but also can visualize many MCU examples. Which is 80–90 % similar to real operating device? The above system does not require carrier signal or a comparator circuit as usually require in conventional triangular PWM generator circuit and thus reduces the cost as well as complexity in producing PWM base drive signals.

V. Acknowledgment The authors pay their sincere gratitude to the Mr I.B rao the MD of power one Microsystems & the Management of Power one Microsystems ,Bangalore for funding this technical work.. The author also extends their heartily thanks to R&D Engineer Mr M. M. Venkateswaran & Mr Valache Siddalingappa, for their valuable time and effort for scrutinizing the design of the project.

References [1] [2] [3] [4] [5] [6]

G.J. Vander et al, “150W Inverter – an optimal design for use in solar home system”, International Symposium on Industrial Electronics, Proceedings ofISIE, 1998, Vol. 1, pp 57-62. B. Lindgrin, “A 110 W inverter for photovoltaic application”, Published in International Journal of Renewable Energy Engineering, April 2002. S. Martínez, M. Castro, R. Antoranz, and F. Aldana, “Off-line uninterruptible power supply with zero transfer time using integrated magnetics,” IEEE Trans. Ind. Electron, vol. 36, no. 3, pp. 441–445, Aug. 1989. M. T. Tsai and C. H. Liu, “Design and implementation of a cost-effective quasi line-interactive UPS with novel topology,” IEEE Trans. Power Electron., vol. 18, no. 4, pp. 1002–1011, Jul 2003 Adel Nasiri, Zhong Nie, Stoyan B. Bekiarov, and Ali Emadi, “ An On-Line UPS System With Power Factor Correction and Electric Isolation Using BIFRED Converter” IEEE transaction on Industrial Electronics, vol, 55.no.2,pp. 722 - 730 ,February 2008. Ross, J., Markvart, T., and He, W.: „Modelling Battery charger Regulation for a Stand-alone Photovoltaic System‟ , Sol. Energy, 2000, 69, (3), pp. 181–190

ABOUT THE AUTHORS MD SHOAIB has obtained his B.Tech degree in EEE from New Horizon College of engineering and currently pursuing his MTECH in power electronics system and control in Manipal University .His area of interest is power converters and embedded systems.

V.NAGARAJ has has obtained his ME in power systems from Mysore university, and He has 34years of teaching experience. He has published 2 research papers at national level. His area of teaching is Applications of soft computing systems to power Systems

www.ijmer.com

1219 | Page

Proteus Based Simulation of PV Inverter for Rural Electrical Service

Recommend Documents