1. Electrical System Design and Basic Control with Simulink
IEEE student board – IEEE PELS/IAS joint chapter
Author: Elisabeth Vandeventer

2. Outline Introduction to the project
Development of a simple wind turbine model
Presentation of the load and grid models
Interconnection of the network elements
Implementation of secondary source and storage
Assignment

3. Introduction to the project
Experimental network for isolated village
100 households, cold climate; 𝑃 𝑙𝑜𝑎𝑑 =33.8𝑘𝑊, 𝑃 𝑙𝑜𝑎𝑑 =90.9𝑘𝑊
Windy area, river nearby
Your goal:
Design a control system to regulate the power flow in the network and make it stand-alone
Your power sources:
Primary: 60kW wind turbine
Secondary: hydropower turbine located on the river
Storage: battery bank

4. Simple wind turbine model
60kW wind turbine
Power curve from provider
Steady-state values  need to make it dynamic
Addition of inertia time constant:
𝐻=2.63× 𝐷 0.12
Final model

5. Load model Dynamic three-phase load Input: PQ
Connect to the three phase grid

6. Infinite grid representation
Three phase, 230Vrms line-to-line
Ideal representation:

7. Interconnection of the blocks
Use of an idealistic converter: use source output power as input and transforms it into 3 phase current waveforms

8. Power flow Primary source uncontrollable
Infinite grid needs to provide power
System is not stand-alone!
Need addition of:
Controllable secondary source: hydropower turbine
Electricity storage: battery bank

9. Hydropower turbine Mathematical model: 𝑃=𝜂𝜌𝑄𝑔ℎ
Addition of inertia time constant 𝐻 𝑡𝑢𝑟𝑏𝑖𝑛𝑒 , maximum power output (saturation) and valve control
Output power sent to ideal converter for connection to the grid
Controlled through the use of the valve

10. Battery bank Available in SimPowerSystems library
Charged/discharged with CCS
Monitoring State Of Charge for control
Use 𝑃=𝑉×𝐼 to send to converter and connect to the grid

11. Assignment – goal
Your goal: (close to) no exchanged power with the grid
𝑃 𝑠𝑜𝑢𝑟𝑐𝑒𝑠 – 𝑃 𝑙𝑜𝑎𝑑 ± 𝑃 𝑠𝑡𝑜𝑟𝑎𝑔𝑒 ≈ 0
How to achieve that:
Resize the secondary source and battery bank
Write a clever control scheme that will handle the power flow

12. Assignment – input and outputs
Inputs to the model:
Load profile
Wind profile
Constant water flow
Quantities to visualize:
Wind power
Hydro power
Load consumption
Battery SOC
Power exchange with the grid

13. Assignment – control signals
Wind power  uncontrollable
Hydropower turbine
Monitor: output power
Control with: valve opening
Battery:
Monitor: state of charge
Control with: power to inject/draw
Infinite grid: power exchange occurs automatically to ensure power balance (nothing to do)

14. Assignment – sources parameters
Wind turbine:
Battery bank
Spec sheet: NPS 60-24
Type: lead-acid
Inertia time constant: 𝐻=2.63× 𝐷 0.12
𝑉 𝑛𝑜𝑚 =24𝑉
Initial SOC: 50%
Hydropower turbine:
Min/max SOC: 15-95%
𝜂=0.95
Response time: 1s
𝜌=1000 𝑘𝑔/ 𝑚 3
Discharge currents: [ ]
𝑔=9.81 𝑚/𝑠
ℎ=20 𝑚
Rated capacity: 16kAh
𝑃 𝑚𝑎𝑥 =30𝑘𝑊
Warning: parameters in red might need to change
GOOD LUCK!