Liquid-cooled drives: How they work and where to use them
Most drives are air-cooled, but liquid-cooled variants can provide greater power densities in smaller spaces for some applications, as Liam Blackshaw, ABB’s UK product manager for LV drives, explains.
Over their lifetime, drives can produce significant amounts of heat, which needs to be dealt with using some form of cooling. There are two main ways of doing this. The traditional method is air cooling, which uses cabinet fans to provide ventilation. This is fine for many applications, but in particularly dirty environments, it can cause a problem because dust and debris in the ambient air can be drawn into the air intake, and damage components. Even with a cabinet filter in place, there is still a chance that small particles can enter the cabinet and cause problems.
The second approach is to use a liquid coolant to transfer heat away from the drive. Because it is a closed system, there is no risk of contaminants entering a liquid-cooled drive and causing problems. It also allows higher protection classes.
Liquid has a far greater heat-carrying capacity – some 3,500 times greater – than that of air. A typical 6MW drive can produce up to 150kW of waste heat while operating, so improved cooling can help significantly with drive system design. Specifically, it can allow more compact designs, or greater power densities in an existing footprint, making it ideal for installations where space is at a premium – particularly in dirty and dusty environments. The reduced need for a cabinet fan and filter system to cool a liquid-cooled drive also means that it can run much more quietly than a fan-cooled equivalent.
Liquid-cooled systems generally cost more upfront, but this typically more than evens out over the lifetime of the drive through improved efficiency and lower maintenance requirements because of the improved heat dissipation.
For marine and offshore environments, much of the liquid cooling infrastructure required – for example, heat exchangers and pipework – may already be in place.
In mines and other dusty environments, liquid cooling can save vast amounts of time and cost during installation by avoiding the need for extensive clean air provision.
For applications where space-saving, durability, low maintenance or silent operation are high priorities, a liquid-cooled drive can often be the most cost-effective option.
To find out more about ABB’s liquid-cooled ACS880LC drive, visit: https://new.abb.com/drives/low-voltage-ac/industrial-drives/acs880-liquid-cooled-drives
