VersaBridge® Classic — medium-voltage variable frequency drive, 2.3–13.8 kV, 1500–40,000 hp

Description

VersaBridge® Classic is a medium-voltage variable frequency drive for motors from 1500 to 40,000 hp at voltages from 2.3 to 13.8 kV. The company began developing its own medium-voltage drive in 2009 and shipped the first VersaBridge in 2014; it now offers a complete variable-speed drive system, including incoming and outgoing switchgear, the medium-voltage drive and the motors. Its main industries are oil and gas, power generation, metals and mining. The patented design is a multilevel cascaded H-bridge: the output voltage is built by connecting single-phase IGBT cells in series, which gives an almost sinusoidal waveform, reduces harmonics and motor torque ripple even at low speeds, and practically removes limits on cable length. Line-side harmonics are so low that the drive is compatible with new and existing motors without an external filter and exceeds the requirements of IEEE-519. The power module electronics are hermetically sealed with a 50 kV dielectric barrier. The modular architecture of standard units (power cells (Cube), sections (Slice) and incoming sections (Mains)) allows the drive to be scaled to different powers with a minimum number of spare parts; the parts are universal for any voltage class and power rating, and the power cells are easy to remove for maintenance. Power cables can enter from the top, from the bottom or from both sides, and no inter-section cabling is needed on site. Each cell has isolating contactors: if a fault occurs, the damaged section is taken out of service and the drive restarts with a spinning-motor pickup. N+1 … N+N redundancy is available as an option to keep running at full power. The drive picks up a rotating load without torque, voltage or current surges, rides through a supply dip of up to five cycles without an external UPS, can start several motors in sequence and synchronously transfer them to the line and back. Communication with SCADA and DCS is via the standard Ethernet Modbus protocol. Applications: reciprocating and centrifugal compressors (example: a 6000 hp compressor at 4160 V), pumps, fans, conveyors, mills. Manufacturing location: Round Rock, Texas.

Technical specifications