Converter Fed Microgrids: Challenges

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Converter Fed Microgrids Challenges Solutions

• Presenter Charles Sao, PhD Candidate, ECE Dept.,
  U. of Toronto
• Contact Info cksao_at_ieee.org Supervisor Prof.
  Peter Lehn

Microgrids Power Network with Loads and DGs
that operate as a Single Controllable System.
Grid Connected Mode

• Current Mode Control Dynamic Current Control
• Synchronized to PCC Voltage Fast P and Q
  Control
• Grid Provides PCC Voltage and Frequency Control

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Microgrids Challenges

• Intentional
• Islanding Mode

• Identical Topology and Control as Grid Connected
  Mode
• Lose Control of PCC Voltage and Frequency
• PQ Supply does NOT equal Demand

Operate Like Conventional Gen?

• Voltage Source with Regulated Voltage Frequency
• Frequency Voltage Droop to Share Real
  Reactive Power
• No Dynamic Control of Current Risk Burn-out (or)
• Conventional P Q Control - Slow

3
Solution Results

• Identical Topology as Grid Connected Mode
• Regulates PCC Voltage and Frequency
• Fast Control of Current and Power to meet Demand

4
Load Sharing of 2 Converters
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Grid Connection Transient
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Islanding Transient
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Summary

• Project Summary
• Identical Controls in Island Grid Connected
  Modes
• Regulate V Freq., Manage P and Q
• Dynamic Current Control to Protect Converters

• Other Research Projects
• Autonomous Load Sharing of Voltage Source
  Converters
• Computing Lightning Exposure of Wind Turbines
  (with Dale Dolan)
• Benchmark System for Time Domain Simulation of
  D-STATCOMs

• Selected Industrial Projects (at BC Hydro)
• Stability study of the North Coast 500 kV Line
• Effect of non-linear loads on reactive power
  metering
• CEA Power Quality Survey Coordination in BC