Qingshan Shan

Estimation of Impulsive Noise in an Electricity Substation

Measurements of impulsive noise in a 400/275/132-kV electricity substation are presented. The measurements are made with three antennas having overlapping bands covering the range 100 MHz-6 GHz. This range includes those bands relevant to modern wireless local area network and wireless personal area network technologies (e.g., IEEE 802.11a/b/g and IEEE 802.15.1/4), which, if proved to be sufficiently robust in the presence of impulsive noise, could play a useful role in substation monitoring and control. Impulsive events are extracted from the measured data using the wavelet packet transform, and the statistical distributions of pulse rate, pulse amplitude, pulse duration, and pulse rise time are presented. An unexpected quasi-periodic component of the noise is observed.

Vulnerability of Zigbee to impulsive noise in electricity substations

The vulnerability of Zigbee technology to noise in an electricity substation environment is assessed. Substation noise obtained from a measurement campaign is modelled as a Symmetric α-Stable process. The parameters of the model are estimated from the measurements and the resulting model is used to investigate the likely BER performance of Zigbee technology deployed in a substation.

Performance of Zigbee in Electricity Supply Substations

A study to assess the impact of partial discharge on the performance of ZigBee equipment in high voltage electricity supply substations is described. The character of partial discharge and ZigBee technology are both briefly reviewed. A field trial system developed for deployment in a 400 kV air insulted substation is described in detail and some preliminary proof-of-system results are presented.

Laboratory Assessment of WLAN Performance Degradation in the Presence of Impulsive Noise

A laboratory test to assess the impact of impulsive noise on the performance of WLAN equipment is described. The test is put in the context of a larger programme of work to assess the performance and reliability of wireless equipment subject to partial discharge noise in high voltage electricity supply substations. The character of partial discharge and WLAN technology are briefly reviewed. The laboratory test methodology is reported and some preliminary results are presented. A related forthcoming field-trial for tests of WLAN equipment in a 275/400 kV air-insulated substation is briefly described.

TEM horn antenna for detection of impulsive noise

A TEM half-horn antenna has been designed and constructed for the detection impulsive noise. The particular application of interest is the recording of partial discharge and/or sferic radiation in a 400 kV electricity transmission substation. The characteristics and performance of the half-horn are presented. Laboratory verification of the antennas utility for the detection partial discharge has been carried out using a partial discharge simulator.

Performance simulations of WLAN and Zigbee in electricity substation impulsive noise environments

A physical layer performance evaluation of WLAN (IEEE 802.11b) and Zigbee (IEEE 802.15.4) receivers in the presence of impulsive noise is presented. Broadband impulsive noise is modeled as a Symmetric Alpha-Stable process. The parameters of the impulsive noise model are estimated from data recorded from an electricity transmission substation (ETS). The results show that the performance degradation of the Zigbee receiver is small whilst the WLAN receiver may suffer more significant degradation.

ZigBee performance in 400 kv air insulated power substation

An experimental assessment of the impact of the electromagnetic environment of a 400 kV substation on the performance of ZigBee equipment is described. The experimental assessment includes a pragmatic field trial and a laboratory test. The laboratory test, in which all external noise and interference are excluded, is used as a control. A simple set of metrics are used to compare the performance of ZigBee equipment deployed in the substation with that deployed in a controlled laboratory environment. The results based on more than 1.6 Gbit of transmitted data show no significant adverse impact of the substation electromagnetic environment on the performance of ZigBee equipment.