Westinghouse Parts Business MG Set Control Power Cabinets

June 1, 2023, 11:37AMSponsored ContentWestinghouse Parts Business
Next Generation MG Control Power Cabinets Installed

Westinghouse Parts Business (WPB) is proud of the first next generation Motor Generator (MG) Set System fully operational at Palo Verde Generating Station. The team completed a first-of-a-kind (FOAK) implementation and installation at the power plant operated by Arizona Public Service (APS), including the next generation MG Control Power Cabinets and new MG Sets. Additionally, Westinghouse installed the new ARCH (Advanced Rod Control Hybrid) system. These systems were installed in a single outage providing additional synergies and cost savings to operations.

ARCH Cabinets Installed

The original MG Set Control Power Cabinets are obsolete and no longer supported. WPB Electrical Engineering looked at researching and developing a product to take the robust switching methodology of the original system and combine it with improvements identified in the AP1000® technology design to develop a replacement system. Our engineering team, working with an outside defense industry firm, developed the new system as a direct replacement that maintains the original auctioneering switching technology and adds in new Man-Machine Interface with additional data capture with output to the plant Distributed Control System (DCS).

Customers can replace the MG Control Power Cabinets with or without replacing the MG Sets. With new MG Sets, features not available at original plant construction can be added and monitored, such as MG vibration and temperature. The use of the next generation rod drive power supply (RDPS), which consists of two MG sets and a new design control cabinet, provided the significant advantage of allowing one MG to be offline for maintenance while the other is powering ARCH. This redundancy allows much more flexibility and single fault tolerance than the original system. Additionally, the new system uses modern components, and provides a significant upgrade in control, indication and maintenance.

Customers may also elect to install this system at the time that they upgrade their Rod Control System from the original analog system with the new Westinghouse ARCH System. APS chose to perform both replacement scopes at the same time. The MG Control Power Cabinet and the Motor Generator can be installed with or without upgrading the Rod Control System.

On Thursday November 10, 2022, the Palo Verde Unit 3 output breakers were closed. This was a complex upgrade to two systems that required integration of Westinghouse I&C and electrical engineering design teams, as well as close coordination with the APS design and installation teams. Walt Drzal, Westinghouse Parts Business Electrical Fulfillment Manager, commented “This extraordinarily complex first-of-a-kind installation included both the MG Set System and the new ARCH System. The Palo Verde Unit 3 installation was the culmination of a 3+ year effort to design, build, integrate and install a major system upgrade for our client. The success of this effort was due to the hardwork and dedication of numerous individuals from Westinghouse, partnering with APS to ensure a successful installation and start-up.”

Productivity and Efficiency

The ARCH system provides real-time capture of all rod steps, eliminating the need to establish modification packages to monitor potential issues in the Control Element Drive Mechanisms (CEDM). The digital system provides advanced monitoring of rod steps to place the CEDM in double hold in the event of system faults to prevent a dropped rod. The MG Control Power Cabinets replace aging and high-maintenance rotating machinery with a modern design. This design includes advanced diagnostic capabilities, modern easily replaceable components and is sized to continue to operate the rod control system normally in the event of partial system failure.


ARCH and MG Control Power Cabinets implementation used a standard design with components tailored as needed for the site installation. These components, such as graphics, operation modes and installation specifics, were implemented with oversight from all impacted parties. This cooperation between operations, maintenance, engineering and Westinghouse allowed for a final product that embraces the standard component philosophy to allow for replication across sites, while addressing the needs specific to Palo Verde.

Westinghouse is excited to be working with the industry on solving this issue. For more information on Westinghouse Parts Solutions visit, www.info.westinghousenuclear.com/westinghouse-parts-business.

Related Articles

Vogtle-4 enters commercial operation

April 29, 2024, 9:32AMNuclear News

Unit 4 at Georgia Power’s Plant Vogtle has entered commercial operation, the company announced today. The new unit can produce enough electricity to power an estimated 500,000 homes and...

Buyers Guide celebrates 55 years

March 15, 2024, 7:00AMNuclear News

The newest edition of the Nuclear News Buyers Guide will be out soon, marking the 55th year of the most comprehensive goods and services publication in the nuclear industry. The American...