Power Systems & Controls, Inc.

Rotary Frequency Converter

SERIES RFC

Guideform Specification

Rotary Frequency Converter Cut Sheet

System Description

The Series RFC rotary frequency converter is designed to supply a source of reliable 50 or 60/400 Hz power to critical loads. Output voltage and frequency are maintained within published specifications by internal control sources. Critical load power is protected from utility transients and brownouts under normal operation.

The RFC rotary frequency converter consists of a common shaft motor-generator (MG) set. The motor can be synchronous type or induction type (depending upon application) designed to meet the rated kVA requirements at the output. The generator is synchronous machine selected to meet the required output power and frequency.

A solid-state voltage regulator controls the generator output voltage providing ±0.5% steady-state regulation. When operated at rated motor speed, the frequency of the generator is controlled by the RPM of the motor. Thus, the output frequency will vary if the input frequency varies.

The PLC control logic for the RFC rotary frequency converter will monitor the input voltage to the motor, and in the event of long term power failure that results in an under-frequency situation or a brownout that results in an overload of the motor, the logic will disconnect the load from the generator and shut down the unit.

In normal operation, the RFC rotary frequency converter acts as a rotating filter against utility transients. In general, it is 100% effective for outages less than approximately ½ second.

The RFC rotary frequency converter is a common shaft two bearing Motor Generator set which uses high-efficient motor and a synchronous generator.  A precision voltage regulator maintains the output voltage ±0.5%. The absence of brushes and slip rings in both motor and generator allows for virtually maintenance free operation.

Design Features

All Series RFC Frequency Converters are designed for continuous, full load operation. Nevertheless, they remain very cost effective at lower load factors. The RFC is ideal for the testing and/or operation of European/Asian equipment or systems to be used in 50 Hz countries.

• Two bearing Motor-Generator Set
• Control and Fault monitoring
• Precision voltage regulator
• Analog metering and controls
• Input and output circuit breakers

Standard features and equipment

• Integrated free-standing metal enclosure with matching battery cabinet
• AC induction motor
• Brushless synchronous generator
• ±10% output voltage adjustment
• Over-frequency and over-frequency protection
• Over-voltage and under-voltage protection
• Sound and vibration enclosure
• Vertical Motor-Generator configuration for minimum footprint
• Battery float voltage automatically adjusts for low AC input voltages
• Superior motor starting capability
• Adjustable battery current limit
• Manually activated timed battery equalize function
• Air-conditioning not required
• Overload protection

Options

• Integrated Touch Screen Controls & Monitoring
• Remote monitor (analog or touch screen)
• Sound enclosure
• Exhaust duct adapter
• Building controls interface
• Special voltages
• Emergency power off interface
• Conduit box extension