Monitoring Power Quality with NOJA Power Reclosers

Customers, and utility regulators, expect power quality. But in the past, power quality data and measurement devices were expensive.

Today, advanced network Intelligent Electronic Devices such as the NOJA Power OSM Recloser offer a suite of Power Quality (PQ) capabilities. These features are all included standard in the system, providing utilities with cost-effective eyes into PQ conditions on the distribution network.

The level of PQ information available is subject to the chosen NOJA Power Recloser Control. Here we explore some of the capabilities of each of the systems.

When using RC-02, RC-03, RC-10 or RC-15 Controls

These series of NOJA Power Recloser Controls share a common signal processing system, providing equivalent data resolution and capture.

All these recloser controllers offer the following PQ metrics:

• Voltage Sags and Swells monitoring
• Harmonic Profiling to the 15th Harmonic (900 Hz on a 60 Hz Network)
• Total Harmonic Distortion and Total Demand Distortion
• Interruptions monitoring
• Oscillography Capture at 1600 Hz

Engineers can capture this data from any NOJA Power OSM Installation with these controllers, and use the free NOJA Power PQS Power Quality Software application to analyse the data.

Data from these Recloser Controllers is captured in the standard COMTRADE or PQD formats, which can be remotely accessed via engineering access (if configured at the recloser).

These open standard formats allow NOJA Power data to be imported into other standards compliant PQ analysis software.

NOJA Power’s RC-20 Controller has significantly improved sampling rates, improving data capture resolution and dynamic range.

The RC-20 sampling rate is 256 samples per cycle, up from the 32 samples per cycle in the earlier generation products.

This expands the RC-20’s Harmonic range up to the 63rd harmonic, and improving the quality of oscillography captures.

The RC-20 also has additional data storage space and expandable memory to house the additional higher resolution data.

Lastly, the RC-20 also adds Synchrophasor Measurement capability, providing GPS timestamped vectors for point-to-point network parameter comparison and advanced network parameter analysis.

Next Steps

“With all of the invertor connected generation being connected to the grid today power quality monitoring is taking on a new and higher level of importance to maintain the reliability and quality of supply to customers,” says NOJA Power Group Managing Director Neil O’Sullivan.

“Our RC range of controls have extensive power quality functionality and our RC-20 control has power quality metering that normally meets utility requirements or power quality metering accuracy and can provide the solution embedded in the circuit breaker protection as an integrated solution. This makes it ideal for renewable energy connections to the grid.”

For utilities using current generation products, enabling the power quality features in NOJA Power’s OSM Recloser system is a simple, cost effective way to capture network performance data from the existing asset base.

It is also a key capability in using NOJA Power Reclosers to connect renewable energy and distributed generation sites.