Electric motors keep tunnel air breathable

Edited by the Engineeringtalk editorial team Jun 18, 2008

Variable speed control through drives enables the ventilation requirements to be precisely met by fan speed and the installation was designed for minimal noise pollution for local residents

Energy efficiency and speed control are essential for effective road tunnel ventilation and Elta Fans selected eight electric motor, drive and control panel packages from WEG Electric Motors (UK) to power ventilation units in the new 1.8km twin tunnels on the A3 Portsmouth London road.

"Health and safety and local environmental considerations mean that proper ventilation and particulate air filtering are required during the tunnelling and lining operations as construction progresses", said Simon Plummer, Project Engineer for Elta Fans.

"Variable speed control through drives enables the ventilation requirements to be precisely met by fan speed and the installation was designed for minimal noise pollution for local residents".

"WEG's package of motors, drives and control panels enables us to achieve the performance we require with excellent energy efficiency".

"With WEG built motors, carefully integrated with WEG drives specifically designed to match the motor characteristics and bespoke control panels, we can provide a highly competitive and efficient package from one source, with excellent availability", said Nick Price, Key Account Manager for WEG (UK) .

"It enables WEG to work together with customers to deliver exactly what they require".

The complete WEG package at the heart of the ventilation system comprises 480V AC high-efficiency induction motors ranging from 160kW to 45kW, with AC inverter drives and associated control panels.

Driving 1.4m diameter contra-rotating fans designed and manufactured by Elta Fans, the ventilation units will meet air handling requirements of up to 132m3/s.

The A3 tunnel project, managed by civil engineers Balfour Beatty Civil Engineering Limited for the Highways Agency, provides a bypass for Hindhead Surrey.

The project connects the two sections of dual carriageway between Portsmouth and London, relieving a well-known traffic bottleneck.

The project is scheduled for completion in 2011 and will help provide better infrastructure access in the South of England during the 2012 London Olympics.