1. Dr Mark Davies Team Leader System Performance WG B4.62 Connection of Windfarms to Weak AC networks

2. Experiences with low SCR connections 1. SVCs on long radial feeder 2. LCC HVDC with very low SCR (near 1 !!) 3. LCC HVDC with WTG interaction 4. VSC HVDC with WTG interaction 5. WTG with SCR < default requirement

3. Item 1: Risk - Understand & Define Generators that require a minimum SCR (e.g. HVDC or WTGs) by implication also create some system degradation.

4. Item 1 : Risk – Managing it How can the system impact: be measured extreme effects be mitigated and a fair system of management be applied?

5. Item 2: Technical – The Challenges 1. Make WTG synchronisation performance closer to that of synchronous generators 2. Make WTGs behave more like synchronous voltage sources

6. Item 2: Technical – Improvements ? Due to their large ratings HVDC systems often operate with low SCR. Can WTG systems leverage off the experiences of these related power conversion devices? Two areas of synergy are: 1. (re)synchronisation performance - (PLL delays) 2. fault current limitation