Manufacturing across borders

EES supplied an excitation system for a steam turbine generator at a UK power station after the previous system’s OEM withdrew technical support. The generator in question produces 120 MW of power with static excitation, so an enormous current is needed to flow in its rotor windings.

The excitation system consists of two cubicles: a high-power unit to manage the amperage and a low-power control panel. Designers separate the two so that operators and engineers can safely work on the control equipment while the high-power section continues to run.

While EES has the capability and facilities to assemble and test the voltage control cubicle in the UK, high-power testing requires a specially designed environment.

Cooperation across borders

Končar has valuable experience in designing and building high-power equipment required for static excitation systems utilised in power generation. Even so, it’s the ability to rigorously test the high-power cubicle on site before shipping it to the UK that is the most valuable asset to EES.

One of the reasons that EES chooses Končar, rather than a British company, is that the Croatian firm is the OEM for the excitation control system, including the low-power section built in Harrogate. EES is the only company to which Končar free issues this product, which reflects the technical trust between the two companies.

Customers have commented on the usefulness of the EES-Končar relationship; EES brings expert knowledge and experience in excitation engineering in situ with the technical backing of Končar as the OEM. This mitigates concerns about future troubleshooting, replacement parts and obsolescence.

The potential cost of obsolescence cannot be underestimated. The process of replacing an excitation control system of this size takes roughly 12 months. If a failure occurs on obsolete and unsupported equipment and the generator becomes unavailable, this can mean a huge loss of revenue. 

Consider a typical energy price of £70 per MWh; this could cost an operator up to £73m in lost income for continuous operation. 

There are challenges associated with this international approach, of course. Many meetings, design reviews and detailed conversations went into the planning of assembly and testing. Managing these interfaces was crucial to avoid any mistakes or project delays. 

Shipping intricately designed electronics is another potential obstacle. Končar engineers stripped back wiring on the high-power cubicle for transport, meaning some testing had to be redone in the UK. However, the Croatian facilities and expertise far outweigh this inconvenience.

Manufacturing for customers

One popular approach that manufacturers use, in parallel with strong relationships with specialist component providers, is incorporating standard control equipment. Bought from UK distributors and widely available, asset owners can easily access technical support and replace and maintain parts, such as relays or power supply units.

Similarly, electrical and electronics engineering firms shouldn’t let geographical borders be a barrier to delivering the best solutions for their customers. The more complex and technical the application, the more important it is to search for the right synergy and partnership first and work out the logistics afterward.

This isn’t always easy. Modern communications technology and engineering software enable this kind of international cooperation where it would have been less feasible even ten years ago.

In the case of the steam turbine generator, EES and Končar engineers used video conference calls and EPLAN, the electrical engineering CAD software, to stay on track. The ability to manage electrical schematics, parts lists and procurement from one program, and share editable files rather than PDFs, was invaluable for quick cooperation.

To ensure Europe’s energy security, knowledge sharing and cohesive technical developments will be more important than ever in the next decade. By establishing partnerships with international counterparts, electrical and electronic engineers can improve their offerings and deliver top value for customers.

Ryan Kavanagh is director at Excitation Engineering Services

To read more about EES’s pursuit of alternative solutions, read Ryan Kavanagh’s explainer on power system modelling for excitation system testing.