1. Hybrid Control of DG to Mitigate Voltage Variation
Aristides Kiprakis
Dr Robin Wallace
University of Edinburgh, UK

2. Automatic Voltage / Power Factor Control (AVPFC)
Active exchange between constant voltage and constant Power Factor (PF) modes
Operates in a defined voltage / PF envelope
Increases exported energy
min disconnection period from over-voltage
Can provide voltage support
Low cost implementation

3. Research Updates - I Combined AVPFC & Voltage Regulator (VR)
major increase in allowable generator capacity
VR under MVAr flow control mode rather than Line Voltage Rise Compensation mode
Developed controller operating at continuous PF that increases exported energy
Fuzzy controller observes the terminal voltage and adjusts the PF set-point accordingly

4. Research Updates - II
DG capacity was further increased by applying similar fuzzy controller to governor
Can also be combined with a Voltage Regulator to increase DG capacity even more

5. Technology Availability
Developed several potential solutions
Proof of Concept models being built to prove feasibility
However…
generator manufacturers must implement them
plant developers must use them and, ultimately,
DNOs need to allow their use in the network

6. CIRED 2003
This work is part of a larger ongoing programme at the University of Edinburgh
Papers presented at CIRED
Intelligent generator control
Domestic CHP
Optimal accommodation of DG