Our custom 3.3 kV slip-ring rotor solution for the High Lift Pump Station (HLPS) at Coppermills Water Treatment Works in London impressed the jury.
Tailor-made replacement: Why only a slip-ring motor solution was feasible
At the heart of our AEMT Awards entry is a project that is exceptional in several respects: the replacement of ten seven-ton 3.3 kV slip-ring rotor motors at a high-lift pump station of a major UK water utility. The existing installation had become increasingly prone to failures – a critical issue, as it supplies drinking water to millions of people across Greater London. Meanwhile, plans for a completely new station are already underway in approximately ten years. The challenge was therefore to deliver a cost-effective and technically reliable interim solution that extends the life of the existing infrastructure.
Many OEMs proposed a conversion to squirrel-cage motors combined with complex VFD systems. However, such a solution would have required extensive structural modifications, additional transformers, large-scale switchgear, and major alterations to the building and electrical infrastructure. In addition to high investment costs, long installation times and additional risks for plant availability would have arisen.
Our engineers therefore deliberately opted for a modern slip-ring rotor solution, fully compatible with the existing installation and capable of using the current starting and control equipment. The concept proved not only technically sound but also significantly more economical and sustainable:
- No structural modifications to the pump station required
- Faster implementation compared to VFD solutions
- Significant cost savings
- 5 % higher efficiency than the old machines
- Expected service life of at least 25 years
- Design takes into account future extreme ambient temperatures
Close collaboration between our motor engineers, the UK team, and the operator’s project team ensured that the large-scale project was completed on budget and on schedule – a decisive contribution to supply security and a prime example of how well-engineered solutions can mitigate multi-million-pound plant risks.
Technical implementation: Precision under high voltage
Our engineers specifically designed the motor solution to meet the requirements of the pump station. The motors feature a robust construction for 3.3 kV slip-ring rotors, engineered for continuous high-load operation, and a customized design precisely adapted to the existing foundation dimensions, connection points, and installation space.
For maximum operational reliability, the motors are equipped with optimized cooling, both air- and water-cooled, in accordance with IC611 and IC81W standards. The design also allows seamless integration into the existing control and starting systems, while production is optimized for flexibility and rapid availability, supported by in-house stock.
The motors were subsequently extensively tested in our Hennigsdorf test facility under real load conditions, finely adjusted, and only delivered after successful acceptance. This approach ensures high reliability and minimizes unplanned downtime, even under demanding operational conditions.
Value for the pump station operator
The new motor solution extends the operational lifespan of the pump station by an additional ten years, increases overall plant efficiency, and simplifies both maintenance and operation, while simultaneously protecting the operator’s investment. By avoiding the implementation of VFD solutions, not only were significant costs saved, but the project timeline was also considerably shortened.
