How to Select the Solution for Power Quality Issues

Poor power quality can lead to significant costs. Not only can it result in power losses, but damaged equipment can be even more expensive, especially if it causes manufacturing downtime.

Often, power quality issues aren’t immediately obvious to the untrained eye.

Common problems like low power factor, voltage imbalances, inrush-induced sags, and harmonics can lead to hefty utility penalties and costly equipment damage if not addressed.

By tackling these power quality challenges, you can avoid extra charges on your electricity bill and protect your electrical equipment. Recognizing the most common symptoms and knowing how to troubleshoot them is the first step in resolving these costly problems.

Common Power Quality Problems

Power quality issues are often caused by two main factors: voltage anomalies and harmonic distortion. These issues can lead to equipment failure and increased operational costs. Here’s a quick overview of common problems:

1. Voltage Dips or Sags

Voltage dips, or sags, are responsible for most power quality issues. They occur when voltage drops below 90% of normal for a short time. Common symptoms include dimming lights, equipment shutdowns, and data loss in electronics. To troubleshoot, monitor the load where symptoms occur, and check the time correlation between equipment failure and voltage dips. Use digital meters or power quality analyzers for accurate measurements.

2. Voltage Swells or Surges

Voltage swells happen when the system voltage increases briefly. They may cause equipment failure, especially power supplies in electronics. To detect swells, monitor voltage trends over time, and compare failure rates across equipment connected to different circuits.

3. Voltage Transients

Transients are brief voltage spikes, often caused by lightning or equipment switching. These can damage electronics and motors. Monitor at the load and track any operational failures to identify the source.

4. Voltage Interruptions

Interruptions last 2-5 seconds or more and cause equipment to stop. Monitoring is key to linking interruptions with operational failures, especially in unattended equipment.

5. Voltage Unbalance

Voltage unbalance occurs when one phase in a three-phase system is overloaded, causing overheating and potential motor damage. It can be detected with a power quality analyzer to ensure the voltage variation doesn’t exceed 2%.

6. Harmonics

Harmonics are unwanted frequencies that disrupt normal power flow. They cause overheating in conductors and transformers and can lead to efficiency losses in motors. Regular monitoring is essential to detect and address harmonics.

Selecting the solution:

Identify the Power Quality Problem: The first step is to analyze the electrical system to pinpoint the issue and identify potential causes. This includes performing on-site measurements and examining voltage and current waveforms to detect harmonics, voltage fluctuations, and other power quality issues.

Assess the Impact: Next, evaluate how the power quality problem affects operations. This involves estimating the costs associated with downtime, production losses, equipment damage, and increased energy consumption due to the problem.

Define Quantitative Objectives: Based on the analysis, set clear, measurable goals for resolving the issue. These objectives might include improving power factor, reducing harmonic distortion, stabilizing voltage, or minimizing downtime and equipment damage.

Identify Possible Solutions: Explore potential solutions, which could include a combination of passive and active harmonic filters, voltage regulators, capacitor banks, and other equipment designed to address specific power quality issues.

Evaluate Each Solution: Evaluate each potential solution based on the objectives defined in Step 3. This assessment should take into account both internal and external factors:

• Internal: Cost, technological effectiveness, and compatibility with existing systems.
• External: Available space, installation conditions (e.g., altitude, contamination, humidity, temperature), and ease of connection.

Select the Best Solution: After evaluating each option, choose the best solution or combination of solutions. The chosen solution should meet the defined objectives while being cost-effective and feasible for implementation.

Implement the Solution: Finally, implement the selected solution. This may involve installing new equipment, modifying existing systems, or adjusting the internal distribution network. After installation, monitor the solution to ensure it effectively resolves the power quality problem.

YT Electric is the biggest OEM manufacturer of low-voltage AHF and SVG with more than 15 years' experience. All products hold certifications for ISO9001, CE, and CQC standards, and type test reports support them.

Contact us for expert guidance:

For more information on how our Active Harmonic Filter and Static Var Generator improve power quality: sales@ytelect.com

Keywords: electronic equipment, active filters, power failure, lightning strikes, control system, large loads, neutral conductors, distribution systems, uninterruptible power supply, power factor correction capacitor