Second Wind - Solutions - Paralleling Transformers with the Phaser

Paralleling Transformers with the Phaser^®

Parallel Transformers

Phasers^® and the PhaserMaster at the substation can make transformer paralleling a reliably safe practice, even in variable bus configurations. There are a few simpler ways to get more useful capacity from transformers than to strategically parallel them. For example, two 40 MVA transformers could not individually service two busses with 20 and 50 MVA loads, but they could if they were tied together.

The trouble is, most Load Tap Changer (LTC) controls are not designed for paralleling. LTC controls normally stabilize transformer output voltages by incrementing tap position to raise voltages if too low, decrementing if too high. Put two transformers in parallel and their LTC controllers will contend: one can increase taps in response to the other's decrease. This leads to VAR imbalances between the two transfomers that drive circulating currents, transformer heating, and subsequent losses. Useful transformer capacity is decreased, and VAR correction capacity is wasted on the transformers.

Replacinng the LTC controllers with networked-together Phasers and a low-cost PhaserMaster controller eliminates these problems. Unlike conventional LTC controllers, Phasers measure all the electrical variables necessary to both regulate voltage and quantify VAR imbalance and circulating currents. The PhaserMaster optimizes all of these using polled Phaser data and reconfigurable transformer nameplate and bus data. PhaserMaster issues tap up/tap down control commands to the LTCs via their Phasers, each of which is outfitted with one of several input/output (I/O) options.

A single PhaserMaster can regulate any number of transformer LTCs at a substation. It can infer which transformers are connected together by mounting bus ties using Phaser I/O, and operate the transformers optimally and without operator intervention.

Of course, the same Phasers can also extend substation SCADA down to the feeder and bus level. PhaserMaster can also provide local display, protocol translation for legacy RTU simulation, Ehternet connectivity, and more. The modularity and flexibility of the Second Wind solution allows as many variations as there are customer needs.


	Remote Wind Data Collection
	Power Performance Testing
	Integrating Met Data into Windfarm SCADA
	Autopilot Windfarm Control
	Forecasting Windfarm Production
	Windfarm Substation Monitoring
	Windfarm FAA Lights Monitoring
	Windfarm Output Curtailment
	Turbine Control and Monitoring with the Phaser
	Paralleling Transformers with the Phaser
	Measure Electrode Usage with the Phaser
	Translate Legacy Protocol with the Phaser
	Encoderless Tap Position Reporting


	Automatic Tap Changer Control of Paralleled Transformers (pdf)