Case Study | Power Distribution


Designing a VFD Line Sync System for Weil Group Helium Processing that could successfully integrate into an E-House.

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Arctic Sands Thermal Industries contacted T&T Power Group on behalf of Weil Group Resources, a developer of global energy and resource projects, to supply power solutions for a large helium processing facility in Saskatchewan.

This new $10 million facility, completed in April 2016 by the Weil Group, supplies refined industrial-grade helium to North American markets. This state-of-the-art facility purifies inert gas from existing wells to a “Grade A” industrial helium, producing over 40 million cubic feet of helium per year. Saskatchewan is excited to welcome the revival of the helium industry through this project, an industry that has been inactive in the province for 50 years.

“At 600V, no other manufacturer/packager offered a proven system for VFD start - synchronize and bypass run.” -Mike Keevill, Artic Sands Thermal Industries



Our client required a custom Variable Frequency Drive (VFD) solution delivered within a set time frame to be successfully integrated into an E-House with its space restrictions and other limitations.


T&T Power Group designed and built a VFD Line Sync system within a short eight week time frame, including delivering the product to Calgary for integration into an E-House.

Challenges for Weil Group's helium project included:

  • Lync syncing and shut-off, which facilitate heat dissipation within the E-House and eliminate the need for additional air conditioning units.
  • Building a system within the space restrictions of the E-House.
  • Keeping harmonic disturbances within the range of IEEE 519: the limits of the VFD running time and syncing to the line also limits the quantity and duration of harmonic disturbances.
  • Starting a high load torque system was not feasible: the site utility power system located at the end of the transmission line was extremely weak (X/R ~ 1). High starting torques on a weak system can lead to power dip and sag, which can adversely affect other plant equipment on the distribution systems.

Challenges aside, our team was able to design a solution whereby a Vacon VFD running a Line Sync application, starts the 675 HP reciprocating compressor under VFD control until it is at line frequency and then switches on a contactor to run directly from the line.

Once the unit is up to line frequency, the Danfoss VACON NXP VFD is able to make small adjustments to the internal frequency reference so that the line voltage angle and VFD voltage angle are within set limits. At this point the VFD is disconnected from the motor and the motor is directly connected to the line with no noticeable power disturbance.