Power Quality is Vital in the Changing Commercial and Industrial Landscape

According to the EPRI (Electric Power Research Institute) 2022 Power Quality Tech Watch newsletter, the estimated annual cost of power quality events to all industrial sectors in the United States is $145 to 230 billion. A one-second outage among industrial and digital economy firms costs $1,477.

It's a common belief that these costs are mainly due to power outages. However, power quality is complex, with internal events such as voltage sags, transients and harmonics contributing to interruptions and downtime. This means utilities only tackle part of the problem despite heavy investments to ensure power reliability.

A Research Gate paper shows that 70% of power quality problems are caused by internal factors such as equipment operation and wiring. A paper by Rockwell Automation explains that power quality issues are largely untracked and take out processes as many as 20-30 times per year.

Given power quality’s impact and complexity, it is not surprising that a 2021 S&C study with Frost and Sullivan found that while utilities have spent considerable sums to modernize the grid, the reliability experience for Commercial and Industrial (C&I) customers had not improved.

Industry 4.0 spotlights power quality

The shift in loads from electro-mechanical to electronic and digital has increased power quality concerns across all types of businesses. While utilities focus on delivering power quality reliably to avoid interruptions, undetected power quality issues lurking within customers’ facilities contribute to plant downtime, equipment replacement, lost work, and missed shipments. In addition to outages, three common power quality problems include:

• Voltage sags
• Transients
• Harmonic distortion

Voltage sags – While these decreases in line voltage lasting at least half a cycle can be attributed to weather and faults on the utility side, a common cause is turning on large loads such as motors. An EPRI study cited by the Rockwell Automation paper found that industrial customers experience an average of 66 voltage sags annually, costing businesses nearly $60 billion.

Transients – Commonly referred to as surges, these sub-cycle disturbances in the AC waveform can be caused by lightning, poor grounding, and switching of inductive loads. Transients can damage sensitive electronic equipment.

Harmonic distortion – This distortion of current and voltage waveforms is caused by momentary on/off switching of loads caused by elevators, HVAC equipment, rectifiers, and welding machines. Harmonic distortion can lead to data corruption, excessive heat, and equipment failure.

Current power quality monitoring and mitigation solutions fall short

Power quality meters are the primary tool utilities use to help identify and characterize power quality disturbances, such as voltage sags and harmonic distortion. These meters typically provide data after the disturbances occur and can only monitor the specific points where they are installed.

Interpreting power quality meter data requires specialized expertise. Interfaces for these meters are generally not user-friendly, and customers usually receive information from utilities through scheduled reports, with no real-time awareness of power quality events or causes.

The humble distribution transformer has a lot to say about power quality

Distribution transformers reliably deliver power to customers around the clock. These silent devices can see power quality events since they are connected to secondary voltage and current on the customer side. Yet distribution transformers are not connected, creating a distribution infrastructure visibility gap.

With transformer connectivity, the secondary voltage and current could be monitored; sags could be traced to connections inside the facility, pinpointing wiring issues or discovering loads connected to a transformer at capacity.

For example, the transformer can detect voltage sags from starting and stopping large motors. Similarly, harmonic distortion can be observed by monitoring secondary current and voltage, enabling customers to locate and mitigate the causes.

Ideally, in addition to monitoring secondary current and voltage, the distribution transformer monitor would close the distribution visibility gap by watching the primary current to see events between the substation and the transformer while monitoring transformer health to prevent outages and increase lifespan.

The power of sensors, communications, and data science

At Ubicquia, we have developed an innovative approach to distribution transformer monitoring to close the visibility gap where 92% of outages occur. Our UbiGrid DTM+ (Distribution Transformer Monitor) platform combines advanced sensor technology, fast and secure LTE communications, and machine learning, providing a cost-effective alternative to current power quality monitoring solutions.

What sets the DTM+ apart from traditional power quality monitoring is its ability to see upstream to the substation, downstream to the customer, and into the transformer and deliver real-time insights and information with our open and user-friendly UbiVu Analytics platform.

With a sampling rate of 130 times per cycle, the DTM+ detects and quickly alerts utilities and customers of voltage sags, transients, and harmonics. By knowing which circuits are connected to the transformer, customers can locate the event's cause.

For example, one of our utility customers discovered that a persistent outage with one of their large industrial customers was caused by a large motor starting up on a circuit wired to a transformer at capacity. Working together with the customer, the issue was quickly resolved by wiring the motor to an underutilized transformer.

Just as importantly, utilities can be alerted to events upstream that could cause outages, such as faults and tree or branch strikes, along with indications of transformer conditions that can cause failures, such as overload, internal faults, and oil leaks.

The UbiGrid DTM+ and UbiVu provide a comprehensive approach to power quality management, helping to reduce outages, secure transformer health, and spot problems such as voltage sags, transients, and harmonic distortion.

Power Quality is imperative for our digital economy 

As the power demand continues to surge, driven by the rapid expansion of data centers and the resurgence of domestic manufacturing, power quality emerges as a paramount concern for utilities and their commercial and industrial (C&I) customers. The Federal Energy Regulatory Commission's (FERC) revised load growth forecast underscores the urgency of this issue, with investments soaring to unprecedented levels.

Distribution transformer monitoring emerges as a crucial tool, empowering utilities and C&I customers with the insights needed to identify and address power quality issues quickly. By leveraging these technologies, we not only mitigate risks and save costs but also pave the way for sustained economic growth and innovation.