January 2021

33 www.drivesncontrols.com January 2021 VARIABLE SPEED-DRIVES n In the spring of 2016, MVG tested the capabilities of the few available matrix converter contenders in its own simulation facility. Among its requirements was a flying start capability to ensure synchronised start- up after automatic deactivation. The electrical components also had to be able to operate year-round in temperatures that could fluctuate widely. One of the systems tested was Yaskawa’s U1000 matrix converter and it ticked all of MVG’s boxes. Launched in 2014, the efficient, regenerative inverter is designed to power induction or permanent magnet motors, with or without speed sensors. It spans power ratings from 2.2–500kW and is capable of direct regeneration without needing any DC bus capacitors. It avoids the need for extra regenerative devices and is designed to deliver ten years of maintenance-free, continuous operation. A built-in SIL3 STO input helps to ensure safety. Although the regenerative energy can be fed back into the electricity network to power other loads, such as lighting, this was not the main reason that MVG chose matrix converters for its escalator application. A more important attraction was that the technology removed the need for braking resistors, greatly simplifying cooling and ventilation. Another attraction was that the converter was able to maintain grid quality during regeneration. The line currents are nearly sinusoidal in both motor and regenerative mode, and harmonics are minimised. This reduces losses in network components, such as transformers, cables and lines, and improves efficiency. Furthermore, it reduces potential interference with other components, helping to avoid downtime, as well as removing the need for complicated procedures to identify the cause of any failures. Integrated EMC filters avoid the need for external components such as DC reactors or LC filters. The matrix converters can save up to 50% of the space needed for conventional drives with regeneration. After testing the matrix converters at subway stations where space is extremely limited, some of the converters are being duct-mounted on the side walls of control cabinets with cooling modules on the outside. They are connected to the MVG control system, allowing their operating data to be monitored in real time. n MVG is mounting the space-saving matrix converters on the side walls of escalator control cabinets S RUWFHO(URI V\ODQ$GQD I ,QIRORJLF 'HVLJQ RUPHUO\ ERWK JHQHUDO SXUSRVH HOHFWURPDJQHWLF G J VFLWHQJDP HUDZWR6VL I I,Q RO\WLFD (XURSH SURYLGH DQG PRWRU VSHFLILF I HVLJQ VR WZDUH Ð Õ Í Ö Ó Ö Î Ð Ê Ë Ì Ú Ð Î Õ ÐÕÊÌ ¯´²³ U6H YLFHV LQFOXGH VRIWZD PRWRU SURWRW\SHV DQG PR ZZZ LQIRORJLF UH WUDLQLQJ FRQVXOWLQJ WRU SURGXFWLRQ IDFLOLWLHV GHVLJQ FR XN a leading m ble changea inter ing Italian b refof Assembly Cen The only Hy s acturer nuf s ld’ ro with the w xes uilt gearbo tre in the UK o-mec dr .co.uk rew .beta-po www .co.u rew sales@beta-po Stock eW See 0161 432 9995 W 24 / k 7 Deliver eW Call today for an immediate quote rvice