- Digital phase converter
A digital phase converter creates a three phase power supply from a single phase supply. A digital signal processor (DSP) is used to control power electronic devices to generate a third voltage, which along with the single-voltage from the supply creates a balanced three-phase power supply.
In one type of digital phase converter the input rectifier consists of IGBTs in series with inductors. The IGBTs are controlled by software in the DSP to draw current from the single-phase line in a sinusoidal fashion, charging capacitors on a constant voltage DC bus. Because the incoming current is sinusoidal, there are no significant harmonics generated back onto the line as there are with the rectifiers found in most VFDs. Thecontrolled rectifier input allows power factor correction.
The output inverter consists of IGBTs that draw on the power of the DC bus to create an AC voltage. A voltage created by power switching devices like IGBTs is not sinusoidal. It is a pulse-width modulated (PWM) waveform very high in harmonic distortion. This PWM voltage is then passed through an inductor/capacitor filter system that produces a sine wave voltage with less than 3% total harmonic distortion (standards for computer grade power allow up to 5% THD). By contrast, VFDs generate a PWM voltage that limits their versatility and makes them unsuitable for many applications. Software in the DSP continually monitors and adjusts this generated voltage to produce a balanced three-phase output at all times. It also provides protective functions by shutting down in case of utility over-voltage and under-voltage or a fault. With the ability to adjust to changing conditions and maintain voltage balance, a digital phase converter can safely and efficiently operate virtually any type of three-phase equipment or any number of multiple loads.
The solid state design results in a relatively small package with no moving parts except for small cooling fans. The converters operate at 95-98% efficiency. When the converter is energized with no load, it consumes very little power.
- RadioWorld Magazine featured article: Harris Impressed by Phase Technologies PT355 by Terry Cockerill, 12.31.2009 http://www.rwonline.com/article/92406
- Wine Business Monthly featured article: What's Cool: Digital Phase Converters November 15, 2008 http://www.winebusiness.com/wbm/?go=getArticle&dataId=59858
- January/February 2008 Vineyard & Winery Management Magazine Featured article "The Digital Converter; A New Way to Generate Three-Phase Electricity for a Winery"] by Ben Guthrie. http://www.phaseperfect.com/files/vawmm_article0108.pdf
- United States Patent #6297971
Wikimedia Foundation. 2010.
Look at other dictionaries:
Digital down converter — In digital signal processing, a digital down converter (DDC) converts a digitized real signal centered at an intermediate frequency (IF) to a basebanded complex signal centered at zero frequency. In addition to downconversion, DDC’s typically… … Wikipedia
Phase converter — A phase converter is a device that converts power provided as single or multiple phases to a different number of phases.The majority of phase converters are used to produce three phase electrical power from a single phase source, thus allowing… … Wikipedia
Digital-to-analog converter — For digital television converter boxes, see digital television adapter. 8 channel digital to analog converter Cirrus Logic CS4382 as used in a soundcard. In electronics, a digital to analog converter (DAC or D to A) is a device that converts a… … Wikipedia
Phase-locked loop — PLL redirects here. For other uses, see PLL (disambiguation). A phase locked loop or phase lock loop (PLL) is a control system that generates an output signal whose phase is related to the phase of an input reference signal. It is an electronic… … Wikipedia
Digital signal processing — (DSP) is concerned with the representation of discrete time signals by a sequence of numbers or symbols and the processing of these signals. Digital signal processing and analog signal processing are subfields of signal processing. DSP includes… … Wikipedia
Digital darkroom — is the hardware, software and techniques used in digital photography that replace the darkroom equivalents, such as enlarging, cropping, dodging and burning, as well as processes that don t have a film equivalent. All photographs benefit from… … Wikipedia
Digital Negative — For the informal use of digital negative , see Raw image format. Digital Negative (DNG) Filename extension .dng Developed by Adobe Systems Initial release … Wikipedia
Digital protective relay — In electrical engineering of power systems, a digital protective relay uses a microcontroller with software based protection algorithms for the detection of electrical faults. Such relays are also termed as microprocessor type protective relays.… … Wikipedia
Digital single-lens reflex camera — Nikon D700 full frame (FX) digital SLR camera … Wikipedia
Digital camera — Digicam redirects here. For the military camouflauge method using micropatterns, see Military camouflage#Digital camouflauge. A digital camera (or digicam) is a camera that takes video or still photographs, or both, digitally by recording images… … Wikipedia