PV Ni-MH Battery System (AC Out) All Rights Reserved Copyright (C) Bee Technologies Corporation 2013 1 Design Kit
Jul 04, 2015
PV Ni-MH Battery System (AC Out)
All Rights Reserved Copyright (C) Bee Technologies Corporation 2013 1
Design Kit
Contents
Slide #
1. Nickel - Metal Hydride Battery
1.1 Ni-MH Battery Specification.................................................................................
1.2 Discharge Time Characteristics...........................................................................
1.3 Battery Voltage vs. SOC Discharge Characteristics.............................................
1.4 Charge Time Characteristics................................................................................
1.5 Battery Voltage vs. SOC Charge Characteristics.................................................
2. Solar Cells
2.1 Solar Cells Specification......................................................................................
2.2 Output Characteristics vs. Incident Solar Radiation.............................................
3. Solar Cell Battery Charger.........................................................................................
3.1 Concept of Simulation PV Ni-MH Battery Charger Circuit....................................
3.2 PV Ni-MH Battery Charger Circuit........................................................................
3.3 Charging Time Characteristics vs. Weather Condition.........................................
3.4 Concept of Simulation PV Ni-MH Battery Charger Circuit + Constant Current.....
3.5 Constant Current PV Ni-MH Battery Charger Circuit............................................
3.6 Charging Time Characteristics vs. Weather Condition + Constant Current..........
4. Simulation PV Ni-MH Battery System in 24hr.
4.1 Concept of Simulation PV Ni-MH Battery System in 24hr....................................
4.2 Short-Circuit Current vs. Time (24hr.)..................................................................
4.3 PV-Battery System Simulation Circuit..................................................................
4.3 PV-Battery System Simulation Result..................................................................
Simulations index............................................................................................................
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17-18
19
20
21-26
27
2 All Rights Reserved Copyright (C) Bee Technologies Corporation 2013
KAWAZAKI’s Ni-MH Batteries : Gigacell (10-180)
• Rated Voltage ..................12 [V]
• Capacity............................177 [Ah] (Approximately)
• Energy Capacity................2.1 [kWh]
• Max Output........................48 [kW]
• Rated Charge................ 0.2C5 [A] ( SoC=100% )
1.1 Ni-MH Battery Specification
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10 Ni-MH cells are
in series.
1.2 Discharge Time Characteristics
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Batteries Pack Model Parameters
NS (number of batteries in series) = 1 Unit (10 Ni-MH cells)
C (capacity) = 177 Ah
SOC1 (initial state of charge) = 1 (100%)
TSCALE (time scale) , simulation : real time
1 : 3600s or
1s : 1h
Discharge Rate : 0.2C(35.4A), 0.5C(88.5A), 1C(177A) and 2C(354A)
TSCALE=3600
means “Time Scale”
(Simulation time :
Real time) is 1:3600
Time
0s 1.0s 2.0s 3.0s 4.0s 5.0s 6.0s
V(HI)
7V
8V
9V
10V
11V
12V
13V
14V
15V
16V
17V
0.2C ( 35.4A )
0.5C ( 88.5A )
1C ( 177A ) 2C ( 354A )
0
Hi
0
0
C1
1n
IN-
OUT+
OUT-
IN+
G1
limit(V(%IN+, %IN-)/0.1m, 0, rate*CAh )GVALUE
PARAMETERS:
rate = 0.2CAh = 177
+ -U1GIGACELL_10-180
TSCALE = 3600
SOC1 = 1NS = 1
1.3 Battery Voltage vs. SOC Discharge Characteristics
• VBAT vs. SOC Discharge Characteristics are compared between measurement data and simulation
data.
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Measurement Simulation
10 Ni-MH cells are in series for
total rated current 12V (Each
cell have 1.2V rated voltage).
7
8
9
10
11
12
13
14
15
16
17
0 0.2 0.4 0.6 0.8 1
Ba
tte
ry V
olt
ag
e (
V)
SOC (%)
0.2C, Dch 2.0C, Dch 5.0C, Dch 8.0C, Dch 11C, Dch
Time
0s 1.0s 2.0s 3.0s 4.0s 5.0s
V(HI)
7V
8V
9V
10V
11V
12V
13V
14V
15V
16V
17V
1.4 Charge Time Characteristics
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Batteries Pack Model Parameters
NS (number of batteries in series) = 1 Unit (10 Ni-MH cells)
C (capacity) = 177 Ah
SOC1 (initial state of charge) = 1 (100%)
TSCALE (time scale) , simulation : real time
1 : 3600s or
1s : 1h
Charge Rate : 0.2C(35.4A), 0.5C(88.5A), and 1C(177A)
TSCALE=3600
means “Time Scale”
(Simulation time :
Real time) is 1:3600
0.2C ( 35.4A )
1C ( 177A )
0.5C ( 88.5A )
PARAMETERS:
rate = 0.2CAh = 177
IN-
OUT+
OUT-
IN+
G1
Limit(V(%IN+, %IN-)/0.1m, 0, rate*CAh ) GVALUE
0
Vin18Vdc
0
0
C1
1n + -U1GIGACELL_10-180
TSCALE = 3600
SOC1 = 0NS = 1
HiHi
7
8
9
10
11
12
13
14
15
16
17
0 0.2 0.4 0.6 0.8 1
Ba
tte
ry V
olt
ag
e (
V)
SOC (%)
0.2C, Ch 2.0C, Ch 3.0C, Ch 5.0C, Ch
1.5 Battery Voltage vs. SOC Charge Characteristics
• VBAT vs. SOC Charge Characteristics are compared between measurement data and simulation
data.
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Measurement Simulation
Suntech’s photovoltaic module : STP140D-12/TEA
• Maximum power (Pmax)............140[W]
• Voltage at Pmax (Vmp).............17.6[V]
• Current at Pmax (Imp)...............7.95[A]
• Short-circuit current (Isc)...........8.33[A]
• Open-circuit voltage(Voc)..........22.4[V]
2.1 Solar Cells Specification
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1482m
m
V_V1
0V 5V 10V 15V 20V 25V
V(V1:+)*I(Isense)
0W
50W
100W
150W
SEL>>
I(Isense)
0A
2A
4A
6A
8A
10A
2.2 Output Characteristics vs. Incident Solar Radiation
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Parameter, SOL is added as
normalized incident radiation,
where SOL=1 for AM1.5
conditions
SOL=1
SOL=0.5
SOL=0.16
SOL=1
SOL=0.5
SOL=0.16
Curr
ent
(A)
Pow
er
(W)
Voltage (V)
STP140D-12/TEA Output Characteristics vs. Incident Solar Radiation
+U1STP140D-12TEASOL = 1
Time
0s 1.0s 2.0s 3.0s 4.0s 5.0s
V(HI)
7V
8V
9V
10V
11V
12V
13V
14V
15V
16V
17V
3. Solar Cell Battery Charger
• Solar Cell charges the Ni-MH battery pack (STP140D-12/TEA) 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.
• Gigacell 10-180 (Ni-MH Battery)
– Charging time is approximately 5 hours with charging rate 0.2C or 35.4A
– Voltage during charging with 0.2C is between 11.8 to 14.2 V
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11.8 V
14.2 V
0.2C or 35.4A
3.1 Concept of Simulation PV Ni-MH Battery Charger Circuit
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Ni-MH Battery Photovoltaic
Module
Over Voltage
Protection Circuit
14.01V Clamp Circuit
Gigacell 10-180 (Kawasaki)
DC12V (10 cells)
177Ah
STP140D-12/TEA (Suntech)
10 panels (parallel)
Vmp=17.6V
Pmax=1.4kW
Short circuit current ISC
depends on condition: SOL
3.2 PV Ni-MH Battery Charger Circuit
• 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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0 0 0 0
0 0 0 0
DMOD
D1
Voch14.01dc
0
0
Hi
0
C1
1n
PARAMETERS:
sol = 1
pv
+ -
U1GIGACELL_10-180TSCALE = 3600
SOC1 = 0NS = 1
+U2
STP140D-12TEASOL = {sol}
0
+U3
+U4
+U7
+U8
+U9
+U10
+U11
0
+U5
+U6
Time
0s 1s 2s 3s 4s 5s 6s 7s 8s 9s 10s
V(X_U1.SOC)
0V
0.25V
0.50V
0.75V
1.00V
3.3 Charging Time Characteristics vs. Weather Condition
• Simulation result shows the charging time for sol = 1, 0.5, and 0.16.
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sol = 1.00
sol = 0.50
sol = 0.16
3.4 Concept of Simulation PV Ni-MH Battery Charger Circuit
+ Constant Current
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Ni-MH Battery Photovoltaic
Module
Over Voltage
Protection Circuit
14.01V Clamp Circuit
Gigacell 10-180 (Kawasaki)
DC12V (10 cells)
177Ah
STP140D-12/TEA
(Suntech)
10 panels (parallel)
Vmp=17.6V
Pmax=1.4kW
Constant
Current
Control
Circuit
Icharge=0.2C (35.4A)
Short circuit current ISC
depends on condition: SOL
3.5 Constant Current PV Ni-MH Battery Charger Circuit
• Input the battery capacity (Ah) and charging current rate (e.g. 0.2*CAh) in the
• “PARAMETERS: CAh = 177 and rate = 0.2 ” to set the charging current.
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0 00
0
0
00
PARAMETERS:
sol = 1
0
+U2
STP140D-12TEASOL = {sol}
0
+U3
+U4
+U7
+U8
+U9
+U10
+U11
0
+U5
+U6
pv
PARAMETERS:
rate = 0.2CAh = 177
IN-
OUT+
OUT-
IN+
G1
Limit(V(%IN+, %IN-)/0.1, 0, rate*CAh)GVALUE
DMOD
D1
Voch14.01dc
0
0
0
Hi
C1
1n
+ -
U1GIGACELL_10-180TSCALE = 3600
SOC1 = 0NS = 1
Time
0s 1s 2s 3s 4s 5s 6s 7s 8s 9s 10s
V(X_U1.SOC)
0V
0.25V
0.50V
0.75V
1.00V
3.6 Charging Time Characteristics vs. Weather Condition
(Constant Current)
• 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 (0.2C), battery can be fully
charged in about 5 hour.
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sol = 1.00
sol = 0.50
sol = 0.16
4.1 Concept of Simulation PV Ni-MH Battery System in 24hr.
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Ni-MH Battery Photovoltaic
Module
Over Voltage
Protection Circuit
14.01V Clamp Circuit
Gigacell 10-180 (Kawasaki)
DC12V (10 cells)
177Ah STP140D-12/TEA
(Suntech)
10 panels (parallel)
Vmp=17.6V
Pmax=1.4kW
Inverter
(DC/AC)
Vopen=11. 6(V)
Vclose= 13.8(V)
The model contains 24hr.
solar power data (example).
Load
VIN=8~16V
VOUT=100Vac, 50Hz
PLOAD=250W
Low-Voltage
Shutdown
Circuit
4.1 Concept of Simulation PV Ni-MH Battery System in 24hr.
(Reference)
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Kawasaki GigaCell website: http://www.khi.co.jp/gigacell/use/sun.html
4.2 Short-Circuit Current vs. Time (24hr.)
• Short-circuit current vs. time characteristics of photovoltaic module STP140D-12/TEA
for 24hours as the solar power profile (example) is included to the model.
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The model contains
24hr. solar power data
(example).
+ U1
STP140D-12TEA_24H_TS3600
Time
0s 1s 2s 3s 4s 5s 6s 7s 8s 9s 10s 12s 14s 16s 18s 20s 22s 24s
I(Isense)
0A
5A
10A
15A
PARAMETERS:
Pload = 250
0
OUT
abs(I(out))
EC
Rf ilt
10k
+ U2
STP140D-12TEA_24H_TS3600
+ U3+ U4
Ronof f 1
100dchth
+ U5
Low-Voltage Shutdown Circuit
Cf ilt8uIC = 0.01
+ U6
Irms
+ U7
Inverter (DC/AC)
DMOD
D1
Voch14.01Vdc
0
0
batt
+ U8
0
+ U9
0
+ U10
pv
+ U11
DMOD
D2
batt1+
-
+
-
S2S
VON = 0.7VOFF = 0.3
ROFF = 10MEGRON = 0.01m
0
0
C1
10n
Vac1
FREQ = 50VAMPL = 1.414VOFF = 0
0
1VAC
C3
100n
IN+
IN-
OUT+
OUT-
E2
IF( V(lctrl) > 0.25 ,Lopen ,Lclose) EVALUE
0
PARAMETERS:
Lopen = 11.6
Lclose = 13.8
IN+
IN-
OUT+
OUT-
E1
IF(V(batt1)>V(dchth),5,0)EVALUE
Conof f1nIC = 5
Ronof f100
Lctrl
PARAMETERS:
n = 1
0
OUT
IN+
IN-
OUT+
OUT-
EVout
IF( V(Irms)>V(Iomax), V(1VAC)*n*limit(V(%IN+, %IN-),7,17)*I(IN)/(V(Irms)+1u), V(1VAC)*100 )
EVALUE
out_ac
IN+
IN-
OUT+
OUT-
ecal_Iomax
n*V(%IN+, %IN-)*I(IN)/100EVALUE
Iomax
0
+ -
U1GIGACELL_10-180TSCALE = 3600
SOC1 = 1NS = 1
Conof f 1100n
IN-
OUT+
OUT-
IN+
G1
Limit( V(%IN+, %IN-)/0.1, 1m, 100*V(Irms)/(n*limit(V(%IN+, %IN-),8,16)) )
GVALUE
IN
Rload
{100*100/Pload}
0 00
0
0
00 0
0
4.3 PV-Battery System Simulation Circuit
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Solar cell model
with 24hr. solar
power data.
Lopen value is load
shutdown voltage.
Lclose value is load
reconnect voltage
SOC1 value is initial
State Of Charge of
the battery, is set as
70% of full voltage.
250(W)
Load
Simulation at 500W load, change Pload from 250(W) to 500(W)
Time
0s 3s 6s 9s 12s 15s 18s 21s 24s
1 V(out_ac) 2 I(IN)
-200V
0V
200V1
15.0A
17.5A
20.0A2
SEL>>SEL>>
V(X_U1.SOC)
0V
1.0V
1 V(batt) 2 I(U1:PLUS)
12V
14V
16V1
-100A
0A
100A2
>>
I(PV)
0A
100A
4.3.1 Simulation Result (SOC1=1, 250W load)
• C1=10n IC=13.7
• Run to time: 24s (24hours in real world)
• Step size: 0.001s
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PV generated current
Battery current
Battery voltage
Battery SOC
Inverter input current
100VAC output
• .Options
• RELTOL=0.01
• ABSTOL=1.0u
• ITL4=1000
SOC1=1 (100%) Fully charged,
stop charging
Battery starts to supply current
when solar power drops.
PV module charge the battery
Charging
time
When battery is discharging , current I(U1:PLUS) is minus and when the battery is charging, the current is plus.
Time
0s 3s 6s 9s 12s 15s 18s 21s 24s
1 V(out_ac) 2 I(IN)
-200V
0V
200V1
15.0A
17.5A
20.0A2
SEL>>SEL>>
V(X_U1.SOC)
0V
1.0V
1 V(batt) 2 I(U1:PLUS)
10.0V
12.5V
15.0V1
>>
-100A
0A
100A2
(8.4725,13.800)
(6.9292,11.587)
I(PV)
0A
100A
4.3.2 Simulation Result (SOC1=0.7, 250W load)
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PV generated current
Battery current
Battery voltage
Battery SOC
DC/DC input current
DC output voltage
SOC1=0.7
V=Lopen V=Lclose
Shutdown
Reconnect
Fully charged,
stop charging
Battery starts to supply current
when solar power drops.
Charging
time
• Run to time: 24s (24hours in real world)
• Step size: 0.01s
• .Options
• RELTOL=0.01
• ABSTOL=1.0u
• ITL4=1000
Time
0s 3s 6s 9s 12s 15s 18s 21s 24s
1 V(out_ac) 2 I(IN)
-200V
0V
200V1
15.0A
17.5A
20.0A2
>>
V(X_U1.SOC)
0V
1.0V
1 V(batt) 2 I(U1:PLUS)
10.0V
12.5V
15.0V1
-100A
0A
100A2
SEL>>SEL>>
(8.3025,13.800)
(2.3577,11.587)
I(PV)
0A
100A
4.3.3 Simulation Result (SOC1=0.3, 250W load)
All Rights Reserved Copyright (C) Bee Technologies Corporation 2013 23
PV generated current
Battery current
Battery voltage
Battery SOC
DC/DC input current
DC output voltage
SOC1=0.7
V=Lopen
V=Lclose
Shutdown Reconnect
Fully charged,
stop charging
Battery starts to supply current
when solar power drops.
Charging time
• Run to time: 24s (24hours in real world)
• Step size: 0.01s
• .Options
• RELTOL=0.01
• ABSTOL=1.0u
• ITL4=1000
4.3.4 Simulation Result (SOC1=0.07, 250W load)
All Rights Reserved Copyright (C) Bee Technologies Corporation 2013 24
PV generated current
Battery current
Battery voltage
Battery SOC
DC/DC input current
DC output voltage
SOC1=0.07
V=Lclose
Shutdown Reconnect
Fully charged,
stop charging
Battery starts to supply current
when solar power drops.
Charging time
• Run to time: 24s (24hours in real world)
• Step size: 0.01s
• .Options
• RELTOL=0.01
• ABSTOL=1.0u
• ITL4=1000
Time
0s 3s 6s 9s 12s 15s 18s 21s 24s
1 V(out_ac) 2 I(IN)
-200V
0V
200V1
15.0A
17.5A
20.0A2
>>
V(X_U1.SOC)
0V
1.0V
1 V(batt) 2 I(U1:PLUS)
10.0V
12.5V
15.0V1
-100A
0A
100A2
SEL>>SEL>>(8.3015,13.800)
I(PV)
0A
100A
Time
0s 3s 6s 9s 12s 15s 18s 21s 24s
1 V(out_ac) 2 I(IN)
-200V
0V
200V1
30A
35A
40A2
SEL>>SEL>>
V(X_U1.SOC)
0V
1.0V
1 V(batt) 2 I(U1:PLUS)
10.0V
12.5V
15.0V1
-100A
0A
100A2
>>
(22.476,11.575)
(8.2935,13.800)
(4.8181,11.600)
I(PV)
0A
100A
4.3.5 Simulation Result (SOC1=1, 500W load)
All Rights Reserved Copyright (C) Bee Technologies Corporation 2013 25
PV generated current
Battery current
Battery voltage
Battery SOC
DC/DC input current
DC output voltage
SOC1=100
Fully charged,
stop charging
Battery supplies current when solar
power drops.
Charging
time
Shutdown
V=Lopen
Shutdown
• C1=10n IC=13.7
• Run to time: 24s (24hours in real world)
• Step size: 0.001s
• .Options
• RELTOL=0.01
• ABSTOL=1.0u
• ITL4=1000
V=Lopen V=Lclose
Reconnected
4.3.4 Simulation Result (Example of Conclusion)
The simulation start from midnight(time=0). The system supplies DC load 250W.
• If initial SOC is 100%,
– this system will never shutdown.
• If initial SOC is 70%,
– this system will shutdown after 6.93 hours (about 6:56AM.).
– system load will reconnect again at 8:28AM.
• If initial SOC is 30%,
– this system will shutdown after 2.36 hours (about 2:21AM.).
– system load will reconnect again at 8:18AM.
• If initial SOC is 7%,
– this system will start shutdown.
– this system will reconnect again at 8:18AM (Morning).
• With the PV generated current profile, battery will fully charged in about 5.48 hours.
The simulation start from midnight(time=0). The system supplies DC load 500W.
• If initial SOC is 100%,
– this system will shutdown after 4.82 hours (about 4:49AM.).
– system load will reconnect again at 8:18AM.
– this system will shutdown again at 10:29PM.
• With the PV generated current profile, battery will fully charged in about 6.15 hours.
All Rights Reserved Copyright (C) Bee Technologies Corporation 2013 26
Simulations index
Simulations Folder name
1. PV Ni-MH Battery Charger Circuit..................................................
2. Constant Current PV Ni-MH Battery Charger Circuit.....................
3. PV-Battery System Simulation Circuit (SOC1=1, 250W)...............
4. PV-Battery System Simulation Circuit (SOC1=0.7, 250W)............
5. PV-Battery System Simulation Circuit (SOC1=0.3, 250W)............
6. PV-Battery System Simulation Circuit (SOC1=0.07, 250W)..........
7. PV-Battery System Simulation Circuit (SOC1=1, 500W)...............
charge-sol
charge-sol-const
sol_24h_soc100
sol_24h_soc70
sol_24h_soc30
sol_24h_soc7
sol_24h_soc100_500W
All Rights Reserved Copyright (C) Bee Technologies Corporation 2013 27