Quartzelec’s New Excitation Control Systems Provide James Cropper with Enhanced Operational Performance

British master papermakers James Cropper turned to Quartzelec to design and deliver a viable and cost-effective replacement for an ‘obsolete’ 50-year old steam turbine generator control panel.

Obsolete and failing control equipment is increasingly putting vital rotating plant at risk and with limited alternatives available from ‘traditional’ OEMs, Quartzelec, because of its experience and design flexibility, is frequently being approached to design, implement and support a range of Automatic Voltage Regulation, excitation control, protection and synchronising equipment.

Having previously delivered various maintenance and support services, initial customer contact in respect to this project was in late 2016, when Quartzelec was tasked with developing this upgrade. This entailed scoping the project, preparing new drawings, full system fabrication and build prior to detailed testing which included dynamic AVR testing using Quartzelec’s newly uprated in-house test capabilities, followed by installation and commissioning completed in late February.

The new generator protection system within the control panel delivers modern standards of equipment protection; replacing the old electro-mechanical relays, previously located in a separate circuit breaker cubicle.  The new control panel incorporates a dual channel DECS 250 based excitation system, P343 generator protection, new synchronisers, a field switch and a Human-Machine Interface to provide operators with the necessary operational feedback, along with automated data logging for easy operation and fault finding. The new excitation control solution also automatically maintains a fixed power factor at a set value while operating under varying loads and voltages.

“The new design developed by Quartzelec uses modern components to deliver increased functionality, performance and reliability whilst remaining true to the original control philosophy,” explained Alan McBirnie, James Cropper’s project manager.

“The previous system only had a manual synchronisation facility for connecting to the network; the new one has provision for either automatic or manual synchronisation, so a true upgrade in performance was also part of the package.  Operator safety and ease of operation were high on our list of requirements and these have been met by replacement of the old manually operated field switch with a modern equivalent which is operated automatically via logic circuits.”

Quartzelec has subsequently provided equipment to upgrade the gas turbine generator control panel, replacing another legacy system, and this will be installed and commissioned during the next scheduled plant shutdown this summer.

Project manager Peter Stuchbury added: “The number of skilled companies now supporting legacy assets like this are dwindling, leaving us perfectly placed, with our long heritage and skilled engineering workforce, to identify, customise and implement a control system upgrade path and provide 24-hour service and spares support. In many instances, the type of solutions we deliver would not be available from traditional OEMs, particularly when a new and sometimes ‘unconventional’ design and fabrication approach is needed to achieve the required solution.

“Being able to specify and incorporate products from a choice of suppliers means we are not being restricted by standard products or solutions. It is essential to ensure that a practical and robust policy is in place for all rotating plant, ultimately minimising the risk of potential failure caused by obsolete control equipment.”

As a leading independent company, Quartzelec initially qualifies what equipment is already in use and then designs a replacement component or upgrade path that suits individual applications based on modern ‘commercial-off -the-shelf’ (COTS) parts. Other bespoke elements are manufactured, as required.  These are supplied in a configuration to suit site specific requirements and can incorporate: individual components; back plate mounted equipment; and a new generator control panel that includes protection and synchronising equipment. These systems are typically pre‑configured and tested before delivery; ready for installation and commissioning by the Quartzelec site team.

Suitable for single and dual channel redundant applications, a range of system architectures are available to satisfy all customer requirements.  Each new compact, modern excitation system offers many benefits including communication and data logging facilities and compatibility with current standards. Quartzelec’s engineering and site support expertise can also be tailored to meet customer requirements and is supported by the appropriate certification. This flexibility of design also ensures minimum site disruption, limits machine downtime, significantly extends the operational effectiveness of the existing equipment and is cost effective.

Stuchbury concluded: “Being able to develop and implement critical excitation control systems and retrofit them to applications means that we are able to provide our worldwide customers with enhanced performance, protection and life extension across a broad range of generator sizes and manufacturers. We typically offer significantly more than that which is available via a traditional OEM. Our system configurations are flexible while remaining competitive within the market and customers are benefiting from the through‑life and life‑extension capabilities and system architectures that Quartzelec makes available.”

Success at Quartzelec

In 2017 Quartzelec celebrated ten years of OEM independence and 100 years of heritage, building its reputation as a cost-effective provider of electrical engineering services. Key to this was strong leadership, a dedicated and knowledgeable 600 plus workforce and a positive ‘can do’ approach that enabled the business to achieve a £63.4m turnover with continual global growth. Commenting on this, Quartzelec MD Daniel Laval concluded: “The past ten years has given us the opportunity to flourish and truly establish ourselves as the competent partner of choice for reliable, responsive and cost effective independent support solutions and we are now consolidating plans to grow the business further over the coming decade and beyond.”

Quartzelec designs, manufactures, repairs, refurbishes and rewinds project-critical motors and generators with state-of-the-art production facilities, an extensive library of design drawings and a full design department and has the ability to work on any OEM‑manufactured machine and/or equipment. It also has a rapidly expanding UK electrical contracting business that delivers both mechanical and electrical installation and maintenance services for an ever-growing portfolio of prestigious projects.

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