PV Lead Acid Battery System Simulation using PSpice or LTspice

1. Design Kit
PV Lead-Acid Battery System
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 1

2. Contents
Slide #
1. Lead-Acid Battery
1.1 Lead-Acid Battery Specification........................................................................... 3
1.2 Discharge Time Characteristics........................................................................... 4
1.3 Charge Time Characteristics................................................................................ 5
2. Solar Cells
2.1 Solar Cells Specification...................................................................................... 6
2.2 Output Characteristics vs. Incident Solar Radiation............................................. 7
3. Solar Cell Battery Charger......................................................................................... 8
3.1 Concept of Simulation PV Lead-Acid Battery Charger Circuit.............................. 9
3.2 PV Lead-Acid Battery Charger Circuit.................................................................. 10
3.3 Charging Time Characteristics vs. Weather Condition......................................... 11
3.4 Concept of Simulation PV Lead-Acid Battery Charger Circuit + Constant
Current................................................................................................................. 12
3.5 Constant Current PV Lead-Acid Battery Charger Circuit...................................... 13
3.6 Charging Time Characteristics vs. Weather Condition + Constant Current.......... 14
4. Simulation PV Lead-Acid Battery System in 24hr.
4.1 Concept of Simulation PV Lead-Acid Battery System in 24hr.............................. 15
4.2 Short-Circuit Current vs. Time (24hr.).................................................................. 16
4.3 PV-Battery System Simulation Circuit.................................................................. 17
4.4 PV-Battery System Simulation Result.................................................................. 18-23
Simulations index............................................................................................................ 24
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 2

3. 1.1 Lead-Acid battery Specification
GS YUASA’s Lead-Acid : MSE-100-6
• Nominal Voltage................ 6.0 [Vdc]
• Capacity............................ 100[Ah]@C10, 65[Ah]@C1
• Rated Charge.................... 0.1C10A
• Input Voltage...................... 6.69 [Vdc]
• Charging time..................... 24 [hours] @0.1C10A
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4. 1.2 Discharge Time Characteristics
6.6V
PARAMETERS:
Idch = {Rate*CxAh}
CxAh = 100
0.25C (25A) Rate = 0.1
Hi
OUT+ IN+
6.0V OUT- IN-
0.1C (10A) U1
PLUS G1
R3 C1 GVALUE
MINUS limit(V(%IN+, %IN-)/1m,0,Idch)
1G 10n
MSE-100-6
TSCALE = 3600
NS = 1
SOC1 = 1
5.4V TSCALE=3600
1C (100A) 0 0 0 0
means time Scale
(Simulation time :
Battery Model Parameters Real time) is 1:3600
0.6C (60A)
NS (number of batteries in unit) = 1 cell
4.8V C (capacity) = 100[Ah]@C10
SOC1 (initial state of charge) = “1” (100%)
TSCALE (time scale) , simulation : real time
1 : 3600s or
1s : 1h
Discharge Rate : 0.1C(10A), 0.25C(25A) , 0.6C(60A), and 1C(100A)
4.2V
10ms 100ms 1.0s 10s 100s
V(HI)
Time
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5. 1.3 Charge Time Characteristics
SOC [%] Vbatt [V] C10A
140V 7.8V 210mA PARAMETERS:
1 2 3 CxAh = 100
Ich = {0.1*CxAh}
120V 7.5V 180mA Hi
IN- OUT-
IN+ OUT+ U1
G1
GVALUE PLUS
100V 7.2V 150mA R3 C1
limit(V(%IN+, %IN-)/0.1m,0,Ich) MINUS 10n
1G
V2 MSE-100-6
6.69 TSCALE = 3600
80V 6.9V 120mA NS = 1
SOC1 = 0
60V 6.6V 90mA 0 0 0 0
Battery Model Parameters
40V 6.3V 60mA NS (number of batteries in series) = 1 cell
C (capacity) = 100[Ah]@C10
SOC1 (initial state of charge) = “1” (100%)
20V 6.0V 30mA
TSCALE (time scale) , simulation : real time
1 : 3600s or
1s : 1h
>>
0V 5.7V 0A
0s 4s 8s 12s 16s 20s 24s Charging Time
1 V(X_U1.1)*100 2 V(HI) 3 I(G1)/100
Time
Input Voltage = 6.69 Vdc
Input Current = 10 A @0.1C10
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6. 2.1 Solar Cells Specification
BP Solar’s photovoltaic module : BP365TS 456mm
• Maximum power (Pmax)..............65[W]
• Voltage at Pmax (Vmp)...............8.7[V]
• Current at Pmax (Imp)................7.5[A]
• Short-circuit current (Isc)............8.1[A]
1513mm
• Open-circuit voltage(Voc)...........11.0[V]
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7. 2.2 Output Characteristics vs. Incident Solar Radiation
BP365TS Output Characteristics vs. Incident Solar Radiation
10A
SOL=1
8A
Current (A)
6A
SOL=0.5
4A
+ U2
2A SOL=0.16
BP365TS
SOL = 1 0A
I(sense)
BP365TS 100W
80W
Power (W)
SOL=1
60W
Parameter, SOL is added as
40W
normalized incident radiation, SOL=0.5
where SOL=1 for AM1.5 20W
conditions SOL=0.16
SEL>>
0W
0V 2V 4V 6V 8V 10V 12V 14V
I(sense)* V(sense:+)
V_V1
Voltage (V)
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8. 3. Solar Cell Battery Charger
• Solar Cell charges the Lead-Acid Battery (MSE-100-6) with direct connect technique.
Choose the solar cell that is able to provide current at charging rate or more with the
maximum power voltage (Vmp) nears the battery charging voltage.
• MSE-100-6
– Charging time is approximately 24 hours with charging rate 0.1C or 10A
– Voltage during charging with 0.1C is between 5.93 to 6.69 V
140V 7.8V 210mA
1 2 3
0.1C or 10A
120V 7.5V 180mA
100V 7.2V 150mA
80V 6.9V 120mA
6.69 V
60V 6.6V 90mA
40V 6.3V 60mA
20V 6.0V
5.93 V
>>
0V 5.7V 0A
0s 4s 8s 12s 16s 20s 24s
1 V(X_U1.1)*100 2 V(HI) 3 I(G1)/100
Time
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9. 3.1 Concept of Simulation PV Lead-Acid Battery
Charger Circuit
Input voltage + VF(D1)
6.69V+0.6V=7.29V
Over Voltage
Protection Circuit
Short circuit current ISC
depends on condition: SOL
7.29V Clamp Circuit
Photovoltaic Lead-Acid
Module Battery
BP 365TS (BP Solar)*3panels MSE-100-6 (GS YUASA)
Vmp(system)=Vmp(panel)=8.7V DC6.0V
Imp=22.5A (7.5A3) 100[Ah]@C10, 65[Ah]@C1
Pmax=195W (65W  3)
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10. 3.2 PV Lead-Acid Battery Charger Circuit
D1
DMOD
Voch
7.29Vdc
pv 0
pv Hi
PARAMETERS:
sol = 1
C1 0
pv pv pv 1n U1
PLUS
MINUS
MSE-100-6
+ U2 + U3 + U4
BP365TS BP365TS BP365TS 0
SOL = {sol} SOL = {sol} SOL = {sol} TSCALE = 3600
BP365TS BP365TS BP365TS SOC1 = 0
0 0 0
• Input value between 0-1 in the “PARAMETERS: sol = ” to set the normalized incident
radiation, where SOL=1 for AM1.5 conditions.
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 10

11. 3.3 Charging Time Characteristics vs. Weather Condition
100V
80V
60V
40V
20V sol = 1.00
sol = 0.50
sol = 0.16
0V
0s 4s 8s 12s 16s 20s 24s
V(X_U1.1)*100
Time
• Simulation result shows the charging time for sol = 1, 0.5, and 0.16.
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 11

12. 3.4 Concept of Simulation PV Lead-Acid Battery Charger Circuit
+ Constant Current
Input voltage + VF(D1)
6.69V+0.6V=7.29V
Over Voltage
Protection Circuit
Short circuit current ISC
depends on condition: SOL
7.29V Clamp Circuit
Constant
Photovoltaic Current Lead-Acid
Module Control Battery
Circuit
BP 365TS (BP Solar)*3panels Icharge=0.1C (10A) MSE-100-6 (GS YUASA)
Vmp(system)=Vmp(panel)=8.7V DC6.0V
Imp=22.5A (7.5A3) 100[Ah]@C10, 65[Ah]@C1
Pmax=195W (65W  3)
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 12

13. 3.5 Constant Current PV Lead-Acid Battery Charger Circuit
PARAMETERS:
CxAh = 100 D1
Ich = {0.1*CxAh} DMOD Voch
7.29Vdc
pv 0
pv Hi
PARAMETERS:
OUT+
OUT-
sol = 1
C1 0
pv pv pv 1n U1
PLUS
MINUS
MSE-100-6
IN+
IN-
+ U2 + U3 + U4
BP365TS BP365TS BP365TS 0
SOL = {sol} SOL = {sol} SOL = {sol} G1 TSCALE = 3600
BP365TS BP365TS BP365TS GVALUE SOC1 = 0
0 0 0
Vmp(system)=Vmp(panel)=8.7V
Imp=22.5A
Pmax=195W
• Input the battery capacity (Ah) and charging current rate (e.g. 0.1*CxAh) in the
• “PARAMETERS: CxAh = 100 and rate = 0.1 ” to set the charging current.
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 13

14. 3.6 Charging Time Characteristics vs. Weather Condition
(Constant Current)
100V
80V
60V
40V
20V sol = 1.00
sol = 0.50
sol = 0.16
0V
0s 2s 4s 6s 8s 10s 12s 14s 16s 18s 20s 22s 24s
V(X_U1.1)*100
Time
• Simulation result shows the charging time for sol = 1, 0.5, and 0.16. If PV can
generate current more than the constant charge rate (0.1), battery can be fully
charged in about 9.364 hour.
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 14

15. 4.1 Concept of Simulation PV Lead-Acid Battery System in 24hr.
Input voltage + VF(D1)
6.69V+0.6V=7.29V Over Voltage
The model contains 24hr. Protection Circuit
solar power data (example).
7.29V Clamp Circuit
Photovoltaic Lead-Acid
Module Battery
Low-Voltage MSE-100-6 (GS YUASA)
BP 365TS (BP Solar)*3panels Shutdown DC6.0V
Vmp(system)=Vmp(panel)=8.7V Circuit 100[Ah]@C10, 65[Ah]@C1
Imp=22.5A (7.5A3)
Pmax=195W (65W  3) Vopen= (V)
Vclose= (V)
DC/DC
DC Load
Converter
VIN=4.5~9.0V VLOAD = 3.3V
VOUT=3.3V ILOAD  18A
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 15

16. 4.2 Short-Circuit Current vs. Time (24hr.)
The model contains
25A 24hr. solar power data
(example).
20A
pv
15A
pv pv pv
+ U2 + U3 + U4
10A
BP365TS BP365TS BP365TS
5A
0 0 0
0A
BP365TS_24H_TS3600
0s 4s 8s 12s 16s 20s 24s
I(sense)
Time
• Short-circuit current vs. time characteristics of photovoltaic module BP365TS for
24hours as the solar power profile (example) is included to the model.
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 16

17. 4.3 PV-Battery System Simulation Circuit
D1
Solar cell model
with 24hr. solar DMOD
Voch
power data. 7.29Vdc
pv 0
D2
batt
DMOD
+ U4 + U3 + U2 C1 0
BP365TS_24H_TS3600 Low-Voltage Shutdown Circuit 0.1n U1
PLUS
MINUS
MSE-100-6
VON = 0.7 0 TSCALE = 3600
E1 SOC1 = 0.7
RON = 10m Ronoff EVALUE
0 0 0 ROFF = 10MEG Ronoff1
Lctrl batt1
+ + OUT+ IN+
- - OUT- IN-
Conoff dchth SOC1 value is initial
S2 1n
0 OUT+ IN+ State Of Charge of
S IC = 5 Conoff1
OUT- IN-
PARAMETERS: E2 the battery, is set as
Lopen = 5.55 EVALUE
70% of full voltage.
Lclose = 6.35 0
DC/DC Converter 60W Load
Lopen value is load (3.3Vx18.181A).
shutdown voltage. PARAMETERS:
n=1 out_dc
Lclose value is load IN OUT
reconnect voltage G1 Iomax
E3 I1
IN+ OUT+ IN+ OUT+
OUT-
IN+ OUT+
OUT-
60W 18.181A
IN- OUT- IN- IN-
GVALUE ecal_Iomax EVALUE
EVALUE 0
0
0  Simulation at 100W load, change I1 from 18.181A to 30.303A
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 17

18. 4.3.1 Simulation Result (SOC1=100, IL=18.18A or 60W load)
20A
PV generated current
10A
0A
I(pv) PV module charge the battery
1 2 15A
7.0V
Battery voltage 5A
6.0V SEL>>
Battery current -15A
1 V(batt) 2 I(U1:PLUS)
100V
Battery SOC 50V SOC1=100%
0V
V(X_U1.1)*100
5.0V 30A
1 2
DC output voltage 20A
2.5V
DC/DC input current >>
0V 0A
0.1s 4.0s 8.0s 12.0s 16.0s 20.0s 24.0s
1 V(out_dc) 2 I(IN) Charging
time Time
• Run to time: 24s (24hours in real world)
• Step size: 0.01s
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 18

19. 4.3.2 Simulation Result (SOC1=70, IL=18.18A or 60W load)
20A
PV generated current
10A
0A
I(pv) PV module charge the battery
V=Lopen
7.0V
1 2 20A (6.9550,5.5528)
Battery voltage
6.0V V=Lclose
Battery current SEL>> (9.584,6.3500)
5.0V -20A
1 V(batt) 2 I(U1:PLUS)
100V
(100.000m,69.972)
Fully charged,
Battery SOC 50V stop charging
SOC1=70%
0V
V(X_U1.1)*100
5.0V 30A Shutdown
1 2
DC output voltage 20A
2.5V
DC/DC input current >> Reconnect
0V 0A
0.1s 4.0s 8.0s 12.0s 16.0s 20.0s 24.0s
1 V(out_dc) 2 I(IN)
Charging Time
time
• Run to time: 24s (24hours in real world)
• .Options ITL4=30
• Step size: 0.01s
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20. 4.3.3 Simulation Result (SOC1=30, IL=18.18A or 60W load)
20A
PV generated current
10A
0A
I(pv) PV module charge the battery
7.0V
1 2 20A
Battery voltage (2.4428,5.5551)
6.0V V=Lclose
Battery current SEL>> (9.1927,6.3500)
V=Lopen
5.0V -20A
1 V(batt) 2 I(U1:PLUS)
100V
(100.000m,30.192) Fully charged,
Battery SOC 50V stop charging
SOC1=30
0V
V(X_U1.1)*100
5.0V 30A
1 2
DC output voltage 20A
Shutdown
2.5V Reconnect
DC/DC input current
>>
0V 0A
0.1s 4.0s 8.0s 12.0s 16.0s 20.0s 24.0s
1 V(out_dc) 2 I(IN) Charging time
Time
• Run to time: 24s (24hours in real world)
• Step size: 0.01s
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21. 4.3.4 Simulation Result (SOC1=10, IL=18.18A or 60W load)
20A
PV generated current
10A
0A
I(pv) PV module charge the battery
V=Lopen
7.0V
1 2 20A
Battery voltage (1.1208,5.5500)
6.0V
Battery current V=Lclose (9.4924,6.3500)
SEL>>
5.0V -20A
1 V(batt) 2 I(U1:PLUS)
100V
SOC1=10
Battery SOC 50V Fully charged,
(100.000u,10.999)
stop charging
0V
V(X_U1.1)*100
5.0V 30A
1 2 Shutdown
DC output voltage 20A
2.5V Reconnect
DC/DC input current
>>
0V 0A
0s 4s 8s 12s 16s 20s 24s
1 V(out_dc) 2 I(IN) Charging time
Time
• Run to time: 24s (24hours in real world)
• Step size: 0.01s
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22. 4.3.5 Simulation Result (SOC1=100, IL=30.30A or 100W load)
20A
PV generated current
10A
0A
I(pv) PV module charge the battery
V=Lclose
7.0V
1 2 20A
Battery voltage (4.8471,5.5500)
(19.118,5.5500)
6.0V
Battery current (7.7024,6.3500)
SEL>>
V=Lopen
5.0V -20A
1 V(batt) 2 I(U1:PLUS) V=Lopen
100V
(10.000m,100.000)
Battery SOC 50V
SOC1=100
0V
V(X_U1.1)*100
5.0V 30A
1 2 Shutdown
DC output voltage 20A Shutdown
2.5V
DC/DC input current >> Reconnect
0V 0A
0s 4s 8s 12s 16s 20s 24s
1 V(out_dc) 2 I(IN)
Charging
time Time
• Run to time: 24s (24hours in real world)
• .Options ITL4=30
• Step size: 0.01s
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23. 4.4 Simulation Result (Example of Conclusion)
The simulation start from midnight(time=0). The system supplies DC load 60W.
• If initial SOC is 100%,
– this system will never shutdown.
• If initial SOC is 70%,
– this system will shutdown after 6.955 hours (about 6:57AM.).
– system load will reconnect again at 9:35AM (Morning).
– With the PV Panel generated current profile, battery will fully charged in about 4.36 hours.
• If initial SOC is 30%,
– this system will shutdown after 2.443 hours (about 2:27AM.).
– system load will reconnect again at 9:12AM (Morning).
– With the PV Panel generated current profile, battery will fully charged in about 4.20 hours.
• If initial SOC is 10%,
– this system will shutdown after 1.121 hours (about 1:07AM.).
– this system will reconnect again at 9:30AM (Morning).
• With the PV Panel generated current profile, battery will fully charged in about 4.14 hours.
The simulation start from midnight(time=0). The system supplies DC load 100W.
• If initial SOC is 100%,
– this system will shutdown after 4.847 hours (about 4:51AM.).
– system load will reconnect again at 7:42AM (Morning).
– this system will shutdown again at 7:07PM (Night).
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24. Simulations index
Simulations Folder name
1. PV Lead-Acid Battery Charger Circuit............................................ charge-sol
2. Constant Current PV Lead-Acid Battery Charger Circuit............... charge-sol-const
3. PV-Battery System Simulation Circuit (SOC1=100, 60W)............. sol_24h_soc100_60W
4. PV-Battery System Simulation Circuit (SOC1=70, 60W)............... sol_24h_soc70_60W
5. PV-Battery System Simulation Circuit (SOC1=30, 60W)............... sol_24h_soc30_60W
6. PV-Battery System Simulation Circuit (SOC1=10, 60W)............... sol_24h_soc10_60W
7. PV-Battery System Simulation Circuit (SOC1=100, 100W)........... sol_24h_soc100_100W
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 24