Category: Case Studies

Solid-State Frequency Converter for a Floating Dry Dock.

In 2008, a large floating dry dock – containing motor loads for cranes, capstans, ballast pumps and fire pumps – was transported to the Grand Bahama Shipyard. The dry dock required 50 Hz power, while the Bahamas utilizes 60 Hz power.

To supply the 50 Hz power needed for the dry dock, two 1000 KVA Caterpillar diesel generators were required. A solid-state frequency converter running off the utility solved this problem.

The second challenge was designing, building and testing a solid-state frequency converter that was rated 2000 KVA and was capable of operating large inductive loads.

FCX engineered the converter to use low frequency-switching to reduce losses. An input voltage of 12.7 KV and an output voltage of 20 KV helped reduce wire costs between the converter and the dry dock.

Two units were manufactured by FCX and the dry dock was electrically divided down the middle. At that time, the dual units comprised the world’s largest solid-state frequency converter.

The two 2000 KVA units may be paralleled at a future date.

Powering F-35s Aboard Aircraft Carriers

Anticipating the deployment of F-35 airplanes aboard aircraft carriers, the U.S. Navy issued a requisition for development of a system to feed power to 400 Hz AC and 270 VCD aircraft with a minimum impact on the existing equipment and space.

FCX used its experience with the 400 Hz AC and 270 VDC high performance power supplies and, by cross utilizing a large portion of the existing 400 Hz system, provided a substantial savings in cost and space.

The actual 270 VDC addition is a small pod that can be mounted in out-of-the-way locations.

Engineering Complex Power Supply for F-22 Test Program

In the early 2000s, the engineering staff from Edwards Air Force Base (AFB) distributed an inquiry regarding a power supply for a 270 VDC military aircraft. FCX did not initially respond to the inquiry, however no viable solutions were presented by the 11 companies that did respond. The engineering staff from Edwards AFB approached FCX to review the specifications and provide a possible solution.

It was not a normal 270 VDC requirement as defined in MIL-STD-704; this required a fast, dynamic response with excellent voltage regulation.

FCX completed its unit and air shipped it to Lockheed Martin’s Vehicle System Simulator in Fort Worth, Texas. After passing stringent test parameters, the unit was subjected to undisclosed tests of a confidential nature, and passed. The FCX solution was cleared for the existing test program and non-disclosed future program requirements.

The same unit was then air shipped to Edwards AFB, installed and commissioned for the first F-22 of the test program.

Replacing Diesel Generators for the Patriot Missile System.

Patriot Missiles, the defensive anti-missile system designed by Raytheon, are installed around the world to protect cities subject to missile attack.

While utility power around the word is either 50 Hz or 60 Hz, the Patriot system incorporates several elements that require reliable 400 Hz power. Therefore, diesel generators are utilized.

Engine generator efficiency is poor, which increases the fuel demand. As operating hours increase, the rotating engines and generators require substantial maintenance.

FCX developed a special solid-state frequency converter, optimized to change the available utility power into the power required by the Patriot system. The FCX solution significantly reduced diesel fuel costs for Patriot Missile System installations worldwide.