デザインキット・PV Li-Ion Battery Systemの解説書

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

2. Contents
Slide #
1. Lithium-Ion Batteries Pack
1.1 Lithium-Ion Batteries Pack Specification.............................................................. 3
1.2 Discharge Time Characteristics........................................................................... 4
1.3 Single Cell Discharge Characteristics.................................................................. 5
1.4 Charge Time Characteristics................................................................................ 6
2. Solar Cells
2.1 Solar Cells Specification...................................................................................... 7
2.2 Output Characteristics vs. Incident Solar Radiation............................................. 8
3. Solar Cell Battery Charger......................................................................................... 9
3.1 Concept of Simulation PV Li-Ion Battery Charger Circuit..................................... 10
3.2 PV Li-Ion Battery Charger Circuit........................................................................ 11
3.3 Charging Time Characteristics vs. Weather Condition......................................... 12
3.4 Concept of Simulation PV Li-Ion Battery Charger Circuit + Constant Current...... 13
3.5 Constant Current PV Li-Ion Battery Charger Circuit............................................. 14
3.6 Charging Time Characteristics vs. Weather Condition + Constant Current.......... 15
4. Simulation PV Li-Ion Battery System in 24hr.
4.1 Concept of Simulation PV Li-Ion Battery System in 24hr..................................... 16
4.2 Short-Circuit Current vs. Time (24hr.).................................................................. 17
4.3 PV-Battery System Simulation Circuit.................................................................. 18
4.3 PV-Battery System Simulation Result.................................................................. 19-23
Simulations index............................................................................................................ 24
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 2

3. 1.1 Lithium-Ion Batteries Pack Specification
BAYSUN’s Lithium-Ion Batteries Pack : Power Battery Plus (PBT-BAT-0001)
• Capacity............................65[Wh], 4400[mAh] (Approximately)
• Rated Current....................3[A]
• Input Voltage.......................20.5 [Vdc]
• Output Voltage....................12.8 ~ 16.4 [Vdc] ( 4 cells )
• Charging time......................5[hours] (Approximately)
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4. 1.2 Discharge Time Characteristics
D1
DMOD
PARAMETERS: Voch
rate = 1 16.8Vdc
CAh = 4400m 0
Hi
0.2C ( 880 mA ) 0
C1 U1
0.5C ( 2200 mA ) IN+ OUT+ 1n + - PBT-BAT-0001
IN- OUT-
G1 0 TSCALE = 3600
GVALUE SOC1 = 100
1C ( 4400 mA ) limit(V(%IN+, %IN-)/0.01, 0, rate*CAh )
TSCALE=3600
0 means time Scale
(Simulation time :
Batteries Pack Model Parameters Real time) is 1:3600
NS (number of batteries in series) = 4 cells
C (capacity) = 4400 mA
SOC1 (initial state of charge) = 100%
TSCALE (time scale) , simulation : real time
1 : 3600s or
1s : 1h
Discharge Rate : 0.2C(880mA), 0.5C(2200mA), and 1C(4400mA)
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5. 1.3 Single Cell Discharge Characteristics
Single cell
Measurement Simulation
4.50
0.2C ( 880mA )
0.5C ( 2200mA )
1.0C ( 4400mA )
4.00
VOLTAGE [V]
3.50
3.00
2.50
2.00
100 90 80 70 60 50 40 30 20 10 0 -10
SOC [%]
• Single cell discharge characteristics are compared between measurement data and simulation
data.
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6. 1.4 Charge Time Characteristics
SOC [%] D1
PARAMETERS:
rate = 0.2 DMOD
CAh = 4400m
G1 Voch
GVALUE 16.8Vdc
Limit(V(%IN+, %IN-)/0.1, 0, rate*CAh ) 0
Hi
OUT+
OUT-
C1 U1 0
1n + - PBT-BAT-0001
IN+
IN-
0 TSCALE = 3600
SOC1 = 0
Vin
20.5Vdc
Vbatt [V] ICharge [A] 0
Batteries Pack Model Parameters
NS (number of batteries in series) = 4 cells
C (capacity) = 4400 mA
SOC1 (initial state of charge) = 100%
TSCALE (time scale) , simulation : real time
1 : 3600s or
1s : 1h
Charger Adaptor
Input Voltage = 20.5 Vdc
Input Current = 880 mA(max.)
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7. 2.1 Solar Cells Specification
BP Solar’s photovoltaic module : SX330
• Maximum power (Pmax)..............30[W]
• Voltage at Pmax (Vmp).............16.8[V]
• Current at Pmax (Imp)...............1.78[A] 502mm
• Short-circuit current (Isc)...........1.94[A]
• Open-circuit voltage(Voc)...........21.0[V]
595mm
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8. 2.2 Output Characteristics vs. Incident Solar Radiation
SX330 Output Characteristics vs. Incident Solar Radiation
SOL=1
Current (A)
SOL=0.5
+
U1 SOL=0.16
SX330
SX330 SOL = 1
SOL=1
Power (W)
Parameter, SOL is added as SOL=0.5
normalized incident radiation,
where SOL=1 for AM1.5 SOL=0.16
conditions
Voltage (V)
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9. 3. Solar Cell Battery Charger
• Solar Cell charges the Li-ion batteries pack (PBT-BAT-001) 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 batteries pack charging voltage.
• PBT-BAT-0001 (Li-ion batteries pack)
– Charging time is approximately 5 hours with charging rate 0.2C or 880mA
– Voltage during charging with 0.2C is between 14.7 to 16.9 V
14.9 V
14.7 V
0.2C or 880mA
All Rights Reserved Copyright (C) Bee Technologies Corporation 2009 9

10. 3.1 Concept of Simulation PV Li-Ion Battery Charger Circuit
Over Voltage
Protection Circuit
Short circuit current ISC
depends on condition: SOL
16.8V Clamp Circuit
Photovoltaic Lithium-Ion
Module Batteries Pack
SX 330 (BP Solar) PBT-BAT-0001 (BAYSUN)
Vmp=16.8V DC12.8～16.4V (4 cells)
Pmax=30W 4400mAh
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11. 3.2 PV Li-Ion Battery Charger Circuit
D1
PARAMETERS:
DMOD
sol = 1
Voch
16.8Vdc
pv 0
Hi
+ C1 U1 0
U2 1n + - PBT-BAT-0001
SX330
SX330 SOL = {sol}
0 TSCALE = 3600
SOC1 = 0
0
• Input value between 0-1 in the “PARAMETERS: sol = ” to set the normalized incident
radiation, where SOL=1 for AM1.5 conditions.
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12. 3.3 Charging Time Characteristics vs. Weather Condition
sol = 1.00
sol = 0.50
sol = 0.16
• Simulation result shows the charging time for sol = 1, 0.5, and 0.16.
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13. 3.4 Concept of Simulation PV Li-Ion Battery Charger Circuit
+ Constant Current
Over Voltage
Protection Circuit
Short circuit current ISC
depends on condition: SOL
16.8V Clamp Circuit
Constant
Photovoltaic Current Lithium-Ion
Module Control Batteries Pack
Circuit
SX 330 (BP Solar) Icharge=0.2C (880mA) PBT-BAT-0001 (BAYSUN)
Vmp=16.8V DC12.8～16.4V (4 cells)
Pmax=30W 4400mAh
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14. 3.5 Constant Current PV Li-Ion Battery Charger Circuit
D1
PARAMETERS: PARAMETERS:
DMOD
sol = 1 rate = 0.2
CAh = 4400m
Voch
16.8Vdc
pv 0
Hi
OUT+
OUT-
+ C1 U1 0
U2 1n + - PBT-BAT-0001
SX330
IN+
IN-
SX330 SOL = {sol}
0 TSCALE = 3600
G1 SOC1 = 0
GVALUE
0 Limit(V(%IN+, %IN-)/0.1, 0, rate*CAh)
• Input the battery capacity (Ah) and charging current rate (e.g. 0.2*CAh) in the
• “PARAMETERS: CAh = 4400m and rate = 0.2 ” to set the charging current.
All Rights Reserved Copyright (C) Bee Technologies Corporation 2009 14

15. 3.6 Charging Time Characteristics vs. Weather Condition
(Constant Current)
sol = 1.00
sol = 0.50
sol = 0.16
• 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 (0.2A), battery can be fully
charged in about 5 hour.
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16. 4.1 Concept of Simulation PV Li-Ion Battery System in 24hr.
Over Voltage
The model contains 24hr. Protection Circuit
solar power data (example).
16.8V Clamp Circuit
Photovoltaic Lithium-Ion
Module Batteries Pack
Low-Voltage PBT-BAT-0001 (BAYSUN)
SX 330 (BP Solar) Shutdown DC12.8～16.4V (4 cells)
Vmp=16.8V Circuit 4400mAh
Pmax=30W
Vopen= (V)
Vclose= (V)
DC/DC
DC Load
Converter
VIN=10~18V VIN = 5V
VOUT=5V IIN = 1.5A
All Rights Reserved Copyright (C) Bee Technologies Corporation 2009 16

17. 4.2 Short-Circuit Current vs. Time (24hr.)
The model contains
24hr. solar power data
(example).
+
U2
SX330 SX330_24H_TS3600
• Short-circuit current vs. time characteristics of photovoltaic module SX330 for 24hours
as the solar power profile (example) is included to the model.
All Rights Reserved Copyright (C) Bee Technologies Corporation 2009 17

18. 4.3 PV-Battery System Simulation Circuit
Solar cell model D1
with 24hr. solar Set initial battery
DMOD
power data. voltage, IC=16.4, for
convergence aid. Voch
16.8Vdc
pv 0
D2
batt
DMOD
C1
+ 100n U1 0
Low-Voltage Shutdown Circuit IC = 16.4 + - PBT-BAT-0001
U2
SX330 SX330_24H_TS3600
VON = 0.7 0 TSCALE = 3600
VOFF = 0.3 E1 SOC1 = 70
RON = 0.01 Ronof f EVALUE
0 ROFF = 10MEG 100 IF(V(batt1)>V(dchth),5,0) Ronof f 1
+ +
Lctrl batt1
OUT+ IN+
C3
- -
Conof f
OUT- IN- dchth 100
10n
S2 1n
SOC1 value is initial
0 OUT+ IN+
S IC = 5
OUT- IN-
Conof f 1
100n
State Of Charge of
PARAMETERS: E2 the battery, is set as
Lopen = 14 EVALUE
IF( V(lctrl) > 0.25 ,Lopen ,Lclose) 70% of full voltage.
Lclose = 15.2 0
Lopen value is load DC/DC Converter 7.5W Load
shutdown voltage. (5Vx1.5A).
PARAMETERS:
Lclose value is load n=1 out_dc
reconnect voltage IN OUT
G1 Iomax I1
E3
IN+ OUT+ 1.5Adc
IN+ OUT+ IN+ OUT+
IN- OUT- IN- OUT- IN- OUT-
GVALUE ecal_Iomax EVALUE
EVALUE IF( I(OUT)-V(Iomax) > 0 ,n*V(%IN+, %IN-)*I(IN)/(I(OUT)+1u), 5 )
0
n*V(%IN+, %IN-)*I(IN)/5
Limit( V(%IN+, %IN-)/0.1, 1m, 5*I(out)/(n*limit(V(%IN+, %IN-),10,25)) )
0
0  Simulation at 15W load, change I1 from 1.5A to 3A
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19. 4.3.1 Simulation Result (SOC1=100)
PV generated current
PV module charge the battery
Battery voltage
Battery current
Battery supplies current when solar
power drops.
Battery SOC SOC1=100 Fully charged,
stop charging
DC output voltage
DC/DC input current
Charging
time
• C1: IC=16.4
• Run to time: 24s (24hours in real world) • .Options ITL4=1000
• Step size: 0.01s
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20. 4.3.2 Simulation Result (SOC1=70)
PV generated current
PV module charge the battery
V=Lopen
Battery voltage
Battery current V=Lclose
Battery supplies current when solar
power drops.
SOC1=70
Battery SOC Fully charged,
stop charging
DC output voltage Shutdown
DC/DC input current
Reconnect
Charging
time
• C1: IC=16.4
• Run to time: 24s (24hours in real world)
• .Options ITL4=1000
• Step size: 0.01s
• SKIPBP
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21. 4.3.3 Simulation Result (SOC1=30)
PV generated current
PV module charge the battery
Battery voltage V=Lopen
Battery current V=Lclose
Battery supplies current when solar
power drops.
Battery SOC Fully charged,
SOC1=30 stop charging
DC output voltage
Shutdown
DC/DC input current
Reconnect
Charging time
• C1: IC=15
• Run to time: 24s (24hours in real world)
• .Options ITL4=1000
• Step size: 0.01s
• Total job time = 2s
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22. 4.3.4 Simulation Result (SOC1=10)
PV generated current
PV module charge the battery
Battery voltage
Battery current V=Lclose
Battery supplies current when solar
power drops.
Battery SOC Fully charged,
SOC1=10 stop charging
DC output voltage
Shutdown
DC/DC input current
Reconnect
Charging time
• C1: IC=14.4
• Run to time: 24s (24hours in real world) • .Options RELTOL=0.01
• Step size: 0.01s • .Options ITL4=1000
• SKIPBP
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23. 4.3.5 Simulation Result (SOC1=100, IL=3A or 15W load)
PV generated current
PV module charge the battery
V=Lopen
Battery voltage V=Lopen
Battery current
Battery supplies current when solar
power drops.
Battery SOC SOC1=100 Fully charged,
stop charging
DC output voltage Shutdown
Shutdown
DC/DC input current
Charging
time
• C1: IC=16.4
• Run to time: 24s (24hours in real world) • .Options ITL4=1000
• Step size: 0.001s
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24. 4.3.4 Simulation Result (Example of Conclusion)
The simulation start from midnight(time=0). The system supplies DC load 7.5W.
• If initial SOC is 100%,
– this system will never shutdown.
• If initial SOC is 70%,
– this system will shutdown after 5.185 hours (about 5:11AM.).
– system load will reconnect again at 7:40AM (Morning).
• If initial SOC is 30%,
– this system will shutdown after 1.633 hours (about 1:38AM.).
– system load will reconnect again at 7:37AM (Morning).
• If initial SOC is 10%,
– this system will start shutdown.
– this system will reconnect again at 7:37AM (Morning).
• With the PV generated current profile, battery will fully charged in about 4.25 hours.
The simulation start from midnight(time=0). The system supplies DC load 15W.
• If initial SOC is 100%,
– this system will shutdown after 3.897 hours (about 3:54AM.).
– system load will reconnect again at 7:37AM (Morning).
– this system will shutdown again at 8:28 PM (Night).
• With the PV generated current profile, battery will fully charged in about 5.5 hours.
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25. Simulations index
Simulations Folder name
1. PV Li-Ion Battery Charger Circuit................................................... charge-sol
2. Constant Current PV Li-Ion Battery Charger Circuit...................... charge-sol-const
3. PV-Battery System Simulation Circuit (SOC1=100)....................... sol_24h_soc100
4. PV-Battery System Simulation Circuit (SOC1=70)......................... sol_24h_soc70
5. PV-Battery System Simulation Circuit (SOC1=30)......................... sol_24h_soc30
6. PV-Battery System Simulation Circuit (SOC1=10)......................... sol_24h_soc10
7. PV-Battery System Simulation Circuit (SOC1=100, 15W)............. sol_24h_soc100_15W
All Rights Reserved Copyright (C) Bee Technologies Corporation 2010 25