New York Power Authority and Clean Path NY Order Four 400 MVA 345 kV Phase-Shifting Transformers to Manage Hudson Valley Loop Flows

To manage congested power flows on the 345 kV Hudson Valley transmission corridor and unlock upstate wind and solar delivery into New York City, NYPA and Cle...

New York Power Authority and Clean Path NY Order Four 400 MVA 345 kV Phase-Shifting Transformers to Manage Hudson Valley Loop Flows

To manage congested power flows on the 345 kV Hudson Valley transmission corridor and unlock upstate wind and solar delivery into New York City, NYPA and Clean Path NY have procured four 400 MVA 345/138 kV Phase-Shifting Transformers (PSTs).

Controlling Unscheduled Power Flow on Key Transmission Corridors

The Hudson Valley 345 kV network frequently suffers from inadvertent parallel loop flows originating from PJM and ISO New England, artificially constraining upstate New York renewable generation. Phase-Shifting Transformers (PSTs) insert a controlled phase angle between input and output voltages.

The four 400 MVA units feature high-speed on-load tap changers (OLTC) capable of adjusting phase shift across ±30 degrees in 1.5-degree increments under active load conditions.

Integration with the Clean Path NY 3,800 MW Renewable Corridor

Clean Path NY combines 3,800 MW of new solar and wind with a 175-mile underground/submarine HVDC line terminating at Rainey Substation in Queens. The new PSTs will balance parallel AC paths around Fraser and Leeds substations.

The first two PSTs will be delivered to Leeds Substation in late 2027, with final commissioning scheduled for early 2028 under New York’s Climate Leadership and Community Protection Act mandate.