Electricity + Control March 2017

DRIVES, MOTORS + SWITCHGEAR

Service-oriented Drive Deployments Improve VSD Driveline Uptime

Philippe Hampikian, Schneider-Electric

Variable Speed Drives (VSDs) were introduced to the market several years ago, and since then, they have proliferated across many industries.

D espite their popularity, much work still needs to be done to fully integrate these technologies in order to develop highly available manufacturing environments. This article explains howVSDs can be utilised as smart devices that help tomonitor system performance and also reveals how these devices can be converted to function as Service-oriented Drives (SODs). Today’s VSD phenomenon can be compared to the state of the automobile in the 1960s. Although many families owned a car dur- ing that era, car safety was not yet a high priority. Over the last 50 years, many automobile safety initiatives were gradually introduced on a number of different levels. As a result of these initiatives, in developed countries, the number of automobile-related deaths de- creased significantly. As with the automobile in the 1960s, even though VSDs have reached a certainmaturity level froman installed base perspective, the ways in which these devices are being implemented and maintained are still immature. This is a problem because users and purchasers of these devices are not leveraging the full energy consumption and equipment uptime benefits of the technology. Most VSDs are installed within a ‘chain’ of other electrome- chanical devices (such as transformers, circuit breakers, motors) or mechanical devices (motors, gear box, mechanical transmission).

Together these all form what we refer to as a ‘driveline’. However, the VSD stands out as being quite different from the rest of its partners in the driveline. VSDs are electronic devices and are the only ‘actors’ in the chain with embedded intelligence. This intelligence allows for the concept of the SOD to become a reality. The SOD concept allows these VSDs to minimise their own downtime and also allows them to be uti- lised as smart sensors for the entire driveline (monitoring, for instance, motor torque temperature,main voltage, and load energy consumption). Today, maintenance managers agree that, in most operations, maintenance practices are 60% reactive, 30% preventive and 10% predictive (see Figure 1 ). Reactive, or corrective maintenance, is a response to an unanticipated problem or emergency. Preventive maintenance implies the systematic inspection and detection of potential failures before they occur. Predictive maintenance is a type of preventive maintenance which estimates and projects equipment condition over time, utilising probability formulas to assess downtime risks. The SOD concept helps facilities managers and maintenance personnel to ‘move the needle’ more in the direction of the anticipa- tive behaviour (predictive) model.

Electricity+Control March ‘17

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