Primary Networks Power Quality Analysis (PNPQA)
|Funding mechanism||Network Innovation Allowance (NIA)|
|Duration||Mar 2018 - Mar 2021|
|Research area||Network Monitoring|
The objectives of this project are to:
- Understand the power quality / harmonics impact of LCTs throughout primary networks in a systematic way;
- Understand the behaviour of PQ monitoring transducers in a systematic way;
- Automate power quality / harmonics data retrieval and analysis processes;
- Develop a decision support tool for modelling and forecasting harmonic / PQ effects
The harmonic content of waveforms and power quality (such as flicker, voltage sags and swells, voltage unbalance) within the primary network is not routinely monitored at present. However, WPD is now required to publish harmonic data in order to facilitate LCT connections.
In addition, there is uncertainty that power quality (PQ) monitors are giving an accurate reflection of power quality and harmonics in different levels of the distribution network. This uncertainty arises from the transducers providing inputs to the monitors, rather than the monitors themselves.
The impact of power electronic devices on the harmonics and power quality of primary networks is currently uncertain. As more and more low carbon technologies (LCTs) are connected with power electronic inverters, the effects on the network, moving forwards, are increasingly unclear. In some situations, the interaction of devices may be constructive and reduce harmonic / power quality issues. In other situations, the devices may interact in a more destructive way. There is also uncertainty surrounding the localisation of harmonic / power quality issues and whether these issues will become more widespread.
Existing business practices use snapshots of PQ data for analysis (for example, a week of data is used to represent the entire year of network operation). The major drawback with this approach is that the data captured during the short monitoring period may not be truly representative of the worst-case network operating conditions, seen during other times of the year. In addition, current business practices are labour-intensive in terms of retrieving data from site and analysing the data. Moreover, current techniques do not give WPD full visibility of power quality / harmonics away from the LCT points of connection.
This project will build on existing best practice, overcoming the limitations outlined above, and evaluate how harmonics and power quality can be monitored and analysed in a cost-effective way across wide areas of the network. The core method for this project shall achieve this by: 1) installing communicating power quality monitors throughout two areas of primary network, and 2) through developing a system that automates power quality data retrieval and analysis tasks. The two areas of primary network will be selected so that comparisons can be made: one area will be chosen with a high penetration of LCTs, whereas the other area will be chosen with a low penetration of LCTs.
The core method is supported by several other activities:
- Investigation of transducer characteristics for harmonics detection;
- Selection of two contrasting areas for trial power quality monitor installations;
- Creation and use of detailed models of the two areas for power quality and harmonics analysis;
- Quantification of the harmonic contributions of different types of power electronic devices.