ATLANTA, August 11, 2008 -- Siemens Energy & Automation, Inc. announced its Siemens Robicon Perfect Harmony Drives? have reached a technical milestone with the introduction of a 8 MW Variable Frequency Drive (VFD) that operates with an output frequency of 500 Hz making it the world’s largest high speed VFD.

This milestone is just the latest for the series of high-speed Siemens Robicon Perfect Harmony drives. While the basic VFD topologies have been limited to output frequencies in the 120 to 200 Hz range, Siemens has already manufactured and installed drives that operate at frequencies between 315 and 400 Hz.

The Siemens Robicon Perfect Harmony power-cell based multilevel arrangement provides a unique topology that allows operation up to 500 Hz, regardless of the VFD power rating. Tests on the VFD control were set to operate the motor in encoderless vector control with 920 Hz IGBT switching frequency, resulting in an effective switching frequency of 9.2 kHz and a sample frequency of 9.2 kHz. This test drive demonstrated very high quality waveform to the motor with low harmonic distortion.

An integrated consistency check establishes the validity of the configuration and reduces the possibility of errors even before the network has been installed. A reporting function quickly creates offers, provides mounting instructions for installation personnel and documents the system for acceptance testing and troubleshooting.

This latest VFD will be used to drive permanent-magnetic motors, such as those found in natural gas processing and transportation applications that require high-speed compression.  Siemens is one of the few companies to design a VFD that can operate with these physically smaller, more efficient permanent-magnetic motors.

“Siemens has been an engineering pioneer for over a century. This latest breakthrough demonstrates our commitment to developing new technologies to increase productivity and energy efficiency for our customers,” says Anne Cooney, Vice President of the Power Conversion Division, Siemens Energy & Automation.

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About Siemens
Siemens Energy & Automation, Inc. is one of Siemens’ operating companies in the U.S. Headquartered in the Atlanta suburb of Alpharetta, Ga., Siemens Energy & Automation, Inc. manufactures and markets one of the world’s broadest ranges of electrical and electronic products, systems and services to industrial and construction market customers. Its technologies range from circuit protection and energy management systems to process control, industrial software and totally integrated automation solutions. The company also has expertise in systems integration, technical services and turnkey industrial systems.

Siemens AG (NYSE: SI) is a global powerhouse in electronics and electrical engineering, and operates in the industry, energy and healthcare sectors.  For more than 160 years, Siemens has built a reputation for leading-edge innovation and the quality of its products, services and solutions.  With nearly 400,000 employees in 190 countries, Siemens reported worldwide sales of $96.6 billion in fiscal 2007.  With its U.S. corporate headquarters in New York City, Siemens in the USA reported sales of $19.8 billion and employs approximately 70,000 people throughout all 50 states and Puerto Rico.