Powerful Starting Converter for the Anshan Steel Plant in China

Challenge

The Anshan steel plant is the third largest in China. In order to keep its blast furnaces running each blower must move huge quan- tities of air – and more precisely 460,000 m²/h. As it is generally the case for blast furnaces, the blowers are only started every four to eight weeks after the blast furnace has been inspected. When starting, the huge drive must be carefully ramped-up in a controlled fashion in order to avoid dangerous electrical or mechanical load peaks.

Solution

The blast furnace blowers are equipped with rugged 42 MW synchronous motors and medium-voltage drive converters. Using these starting converters, the motor can be started from standstill in between one and two minutes and then connected to the line supply. The transition is bumpless – and the starting converter ensures that the start is especially safe and reliable. If a start attempt is unsuccessful – for example due to a brief voltage dip while starting – then a new start attempt can be immediately made without incurring any damage.

Advantages

Less wear and longer lifetime of the components
With over 99% a significantly higher quota of successful starts
Harmonized, almost maintenance-free motor-drive converter system
Maximum plant availability