Real-Time calculation of common power quality indices on Linux RT-Patch

Abstract

Use of Linux with real-time capabilities is a common study in control systems and data processing due to programmer-friendly libraries, huge community support and free software. Real-time Linux with low-cost single board computers (SBCs) present a powerful evaluation environment for developers and researchers today. In this paper, a power signal processing application using Linux RT-Patch is realized. To evaluate the application, both real-time and non-real-time versions tested on single board computers Beaglebone Black and Raspberry Pi 3. Under load conditions, the non-real-time version of the application failed on Beaglebone Black by exceeding the real-time dead-line time of 20 ms consecutively. Raspberry Pi 3 succeeded even with non-real-time operation under load conditions. For both computers, the real-time version of the applications succeeded with a mean processing time under 10 ms. According to processing times, real-time operation brings a great performance enhancement particularly on Beaglebone Black with single core ARM processor. The measurement results show that the proposed system can be used for smart power metering and power signal acquisition purposes.

Keywords

• Harmonics Detection
• Real-Time Operating System
• RT-Patch
• Single Board Computer

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