Despite their differences, continuous-process industries share underlying characteristics: they maintain continuous operations in facilities that represent substantial start-up costs and time, but can be interrupted or disrupted by seemingly minor fluctuations in power quality. If the product stream is disrupted, lost productivity and lost product can create a large financial burden. Zum Beispiel, a voltage sag in a paper mill can waste a whole day of production and inflict a $250,000 Verlust, while a 5-cycle interruption at a glass manufacturing facility can cost a minimum of $200,000.
Duke Energy is one of the most proactive utilities in providing power quality solutions for its customers. The company’s Power Quality Group goes beyond the electric meter, right into its customers’ plants, to help eliminate power quality problems.
To document the interaction of power quality and process quality for continuous-process industries, Duke Energy and Clemson University developed a Webstand simulator in the Power Quality Lab of Clemson University in South Carolina. The Webstand, a portable, process-level power quality research tool, models the winding/unwinding (web) processes typical of the textile industry. The Webstand incorporates the Encore Series to monitor and model the interactions between power quality and process quality, enabling improvements to the system’s robustness without impacting the facility’s production. The Webstand was subjected to numerous dips of various magnitudes, durations and combination of phases. The resulting data provided the information necessary to:
- Determine sources of potential process interruptions
- Validate control system models
- Anticipate the correct output for a given duration based on the magnitude of a sag
- Anticipate the speed of degradation for system components
- Establish individual quality of process and quality of power supply requirements to maintain consistent product quality performance
Following the proof-of-concept, die Encore Series configuration used at the Clemson Power Quality Lab was expanded for installation at a thin-film extrusion plant that operates with an allowable downtime of 4 hours per year. The resulting system is capable of monitoring critical points throughout the system, including the various winders/unwinders, laminators, infeed and accumulator load cells, metering roll, chill roll, fire alarm system and electric supply distribution system. Überwachungsdaten können schnell erkennen, ob ein Fehler im Verteilungssystem oder innerhalb der Anlage aufgetreten ist und welche mögliche Ursache die Störung hat, zusammen mit der Korrelation des Effekts in der Produktionslinie.
Der Einsatz der Encore-Serie zur Qualitätsüberwachung von Prozessen trägt dazu bei, sicherzustellen, dass kritische Prozessanlagen ordnungsgemäß funktionieren, dass industrielle Prozesse nicht unterbrochen werden, und das Wichtigste, dass die Qualität des Endprodukts stets seinen Spezifikationen entspricht.
Quelle:
Dranetz
1000 Neue Durham Road, Edison, NJ 08818
Gebührenfrei: 800-372-6832
Telefon 732-287-3680