Development of control and power electronics schemes for a smart
micro grid with high penetration of PV generation and electric
vehicles
University of Northumbria Newcastle (UNN)
Forecasting – Markov chain
 Take historical data let’s say 5 years and then use it to predict.
 Divide the data in different transition/chunks
 e.g. if irradiance is between 0 to 1000 (divide it in to states)
 0 to 100, 100 to 200, … , 800 to 1000 (let’s say 10 states)
 more states↑ more accuracy↑
 Count the number of transitions between these states, e.g.
 State 1 to 2: how many times
 State 2 to 1: how many times, and so on.
 Find probability matrix (Pm)
 Each state transition/ transition of specific state to all the states
 A specific time period is defined while creating probability matrix (such as min, hr, day) – system training
 Take an initial guess (e.g, irradiance at the current day) and find the prediction of next hr or couple of hours as:
𝐼𝑅 𝑛 = 𝐼𝑅𝑜 𝑃𝑚 𝑛 ; n is number of hr after which prediction is required
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Forecasting – Markov chain
Training based on previous data
Analyze data
Define states based on analyzed data
Data
Data
2
1
5
2
6
states
Sort data to states
Data
States
2
1
5
2
3
6
2
7
4
7
3
8
5
8
3
9
6
9
3
7
7
7
3
6
8
6
2
5
9
5
2
3
State 1
State 2
State 3
Find probability matrix
𝑇1→1
𝑇1→𝑎𝑙𝑙
𝑇2→1
𝑃𝑚 =
𝑇2→𝑎𝑙𝑙
𝑇3→1
𝑇1→𝑎𝑙𝑙
𝑃𝑚 =
0
1
0
3
0
4
1
1
2
3
1
4
𝑇1→2
𝑇1→𝑎𝑙𝑙
𝑇2→2
𝑇1→𝑎𝑙𝑙
𝑇3→2
𝑇1→𝑎𝑙𝑙
0
1
1
3
3
4
0
=0
0
𝑇1→3
𝑇1→𝑎𝑙𝑙
𝑇2→3
𝑇1→𝑎𝑙𝑙
𝑇3→3
𝑇1→𝑎𝑙𝑙
1
0.666
0.25
0
0.333
0.75
MG – Development
 The link between basytec and its own software reading over
CAN is developed.
 The link between dSPACE and Basytec is still under process
 The dspace sending or receiving is not running as expected
– New CAN bus adapter arrived to send or recieve known
signal and test the working of dSPACE
 One, we are able to read send signal using dSPACE, next
step would be sending commands from dSPACE and
reading inside Basytec.
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MG – Development
5
MG – smart charger
 Main Specification:
 Input AC 230V
 Output DC 26,5V/29,2V/30,4V
 Over-voltage protection
 Protection reverse polarity
 LED indicator of charging status
 Active cooling - fan
 BMS option - connector for connect to the BMS (Battery
Management System)
 Small size and low weight
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MG – smart charger – BMS support
Brown connected
to GND
OFF
Blue connected to LOW
GND
Common GND
GND
1.Full charging 20 A
2.Slow charging 5A
3.Stop charging 0A
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By connecting the brown wire to GND,
the charger switches off
By connecting the Blue wire to GND,
the charger switches from high current
to low current.
By connecting both brown and blue
wire to GND, the charger switches off
also. Therefore it is possible to stop low
charging by using brown wire.
MG – smart charger – BMS support
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Smart charger – within dSPACE
Factor considered by control unit:
User requirements (waiting time for charging and
next journey length)
The user provide information about their stay and
the length of next journey. Based on that a target
SOC is set and together with measured SOC, target
C-rate is determined.
Grid voltage conditions
The lower and upper grid voltage limits are
defined in order to staying within the assigned grid
limits (such as for UK 400/230 V, the limits are
0.94 p.u. (min) and 1.1 p.u. (max).
PV system measurements
Monitoring the output of generation from PV and
generate the charging signal.
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Thanks for your attention
Q&A session
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