������Ƶ

In his oration, Prof. Umar emphasized that the sustainability of Indonesia’s power system doesn’t rely solely on the development of new infrastructure, but equally on the effective management of existing assets. Among these, high-voltage testing stands as a cornerstone in safeguarding equipment performance and ensuring reliability.

Challenges in Indonesia’s Power System

The use of electricity in Indonesia was first recorded in 1882, when it powered a Dutch-owned factory in Semarang. A few years later, in 1897, the first power plant was established in Batavia (now Jakarta). Following independence, on October 27, 1945, President Soekarno founded the Electricity and Gas Bureau, which later evolved into Perusahaan Listrik Negara (PLN), the state-owned company that remains the backbone of Indonesia’s electricity provision today.

This long journey has led to a remarkable increase in electrification, largely driven by the expansion of power infrastructure assets. By 2024, Indonesia’s electrification ratio reached 99.83%, signaling near-universal access to electricity. However, despite this achievement, major challenges remain—aging infrastructure, system complexity and dynamic loads, the integration of renewable energy, and demands for higher efficiency and reliability.

“The solution lies in optimizing power asset management,” said Prof. Umar.

Power Asset Management

As of June 2025, PLN manages electricity assets worth approximately IDR 1,796.64 trillion. This figure is not just a statistic but also a profound responsibility. Managing such a vast asset base means ensuring that every component, including spanning generation, transmission, and distribution functions reliably throughout its lifecycle, from planning and design, to installation, operation, maintenance, and eventual replacement.

Prof. Umar explained that asset management is a structured approach to decision making and implementation aimed at achieving an optimal balance between performance, cost, and risk. In the power sector, it plays a central role in maintaining infrastructure reliability, ensuring service quality, and managing risks associated with asset value. Effective asset management encompasses strategic planning, data driven decision making, lifecycle activities, asset data management, organizational capacity, and risk management.

The Role of High-Voltage Testing in Asset Management

The lifecycle of power equipment spans multiple stages, including planning, design, fabrication and testing, transportation, operation, maintenance, service-life evaluation, and replacement. At each stage, high-voltage testing is essential for validating equipment integrity and ensuring it meets performance standards.

High-voltage testing serves multiple functions: validating equipment through Factory Acceptance Tests (FAT) and Site Acceptance Tests (SAT), detecting early signs of failure, supporting remaining-life assessments and investment planning, and verifying post-refurbishment performance. Beyond reliability, such testing is also critical to ensuring safety for both infrastructure and personnel.

A major cause of premature equipment failure is partial discharge, a phenomenon triggered by particles or contaminants that cause localized electrical discharges. Left unaddressed, this can lead to breakdowns, generating electromagnetic waves, acoustic signals, and gas decomposition within insulating materials. Detecting partial discharge early is therefore vital to preventing equipment failure.

Development of a Partial Discharge Sensor

To address this challenge, Prof. Umar and his research team have developed a novel partial discharge sensor. The sensor offers several advantages: it is non-contact with high voltage, wide-bandwidth, low-cost, easy to fabricate, and highly sensitive. This high sensitivity enables it to capture partial discharge signals from a distance and provide detailed frequency spectrum mapping.

“This sensor can detect partial discharge phenomena from a significant distance away from high-voltage equipment,” he explained.

The research progressed systematically through design, fabrication, and laboratory as well as field testing. Field trials were conducted at a 150 kV substation to evaluate real-world performance. Key findings include:

The proposed UHF sensor effectively detected partial discharge signals at a distance of 30 cm from the Cable Sealing End (CSE), with double the sensitivity of conventional HFCT sensors.

The sensor successfully mapped discharge frequencies from 50 MHz to 1000 MHz, making it suitable for both medium- and high-voltage equipment.

Older CSEs displayed higher discharge magnitudes compared to newer ones, particularly on phase B, indicating aging degradation and the need for timely maintenance or replacement.

Applications of High-Voltage Testing in Asset Management

The application of high-voltage testing is central to ensuring both reliability and safety in power systems. Case studies on high-voltage cable sealing-ends, for instance, demonstrate that partial discharge can arise not only from aging but also from installation imperfections. This underscores the importance of post-installation monitoring.

Additionally, health index calculations based on high-voltage test results offer valuable insights for asset management. These indices help forecast overhaul needs and guide budget prioritization based on actual asset conditions and associated risks. Such methods support decision-making in transformer refurbishment and GIS overhauls, combining technical, financial, and risk assessments to create effective roadmaps.

Remaining-life assessment further enhances predictive capability, enabling more accurate failure forecasts and well-targeted mitigation strategies. Reliability- and risk-based maintenance (RCM and RBM) also provide systematic evaluations of transformers, circuit breakers, and protection systems, incorporating Failure Mode and Effects Analysis (FMEA) or Failure Mode, Effects, and Criticality Analysis (FMECA).

Prof. Umar also proposed a digital asset management framework that integrates condition monitoring and sensing data to strengthen high-voltage testing effectiveness. Rather than serving merely as an early warning tool, testing data is collected, analyzed, and simulated to support strategic decisions in both investment and maintenance. This approach elevates high-voltage testing into a comprehensive instrument for equipment validation, service-life calculation, investment planning, and system as well as personnel safety enhancement.