Optimizing Semiconductor Production with Omniverter's AVC

The Situation and Problem

A solar cell manufacturer in Northern USA faced significant challenges in their production process. Specializing in transforming silicon ingots into thin wafers, operational disruptions due to wire breakage during thunderstorms led to considerable financial losses.

The manufacturer begins with cutting silicon ingots into "bricks" for slicing into wafers less than 2mm thick using a fine wire saw. This precision process, crucial for producing hundreds of wafers from each brick valued at thousands of dollars, depends on consistent wire tension. Variability can damage wafers, making them unusable, and wire breakages—up to 20 times a year, often during thunderstorms—result in significant losses. To mitigate risk, operations were halted when storms threatened, impacting productivity.

The Analysis and Diagnosis

Powered by a 35kV underground cable and stepped down to 480V for production, the facility's power quality meters, installed in collaboration with their utility, traced the operational disruptions to voltage sags. These sags, mostly single-phase events likely caused by lightning strikes, could lead to wire tension issues, damaging the wafers or breaking the wire.

The Solution

To address these challenges, Omniverter installed a 1600kVA Active Voltage Conditioner (AVC) on a line of 31 wire saws. Tailored to correct three-phase voltage sags from 70% and single-phase sags from 45% of nominal voltage, this AVC countered over 95% of the power quality events recorded. Additionally, it adjusted minor voltage fluctuations to maintain steady wire tension, crucial for the saws' accuracy.

The Impact and ROI

Post-installation, incidents of wire breakage due to voltage sags were eliminated, significantly enhancing productivity. The Plant Engineer confirmed the AVC's dramatic impact, noting that the investment recouped its costs in under a year.

Implementing Omniverter's AVC has markedly improved the manufacturer's operational efficiency and resource utilization, illustrating the value of precise power quality solutions in semiconductor fabrication. This initiative not only protected valuable assets but also stabilized production processes, highlighting a forward step in high-tech manufacturing.