Partial Discharge Detection and localization Using Software Defined Radio in the future smart grid

Partial discharge (PD) occurs if a high voltage is applied to insulation that contains voids. PD is one of the predominant factors to be controlled to ensure reliability and undisrupted functions of power generators, motors, Gas Insulated Switchgear (GIS) and grid connected power distribution equipment. PD can degrade insulation and if left untreated can cause catastrophic insulation failure. However, PD pulse monitoring and detection can save cost and life prior to plant failure. PD is detected using traditional methods such as galvanic contact methods or UHF PD detection methods. Recently, an alternative method for PD detection and monitoring using wireless technology has become possible. Software Defined Radio has opened new opportunities to detect and monitor PD activity. This research makes use of SDR technology for PD detection and monitoring. The main advantages of SDR technology are that it is cost-effective and it is relatively immune against environmental noise. This is because the noise at electrical power stations is from around a few KHz to a few MHz and this is well below the SDR frequency range and PD frequency band (50-800 MHz). However, noise or interference also exists in the PD frequency band. These interferences are narrow band and mainly from FM, TV broadcasting and mobile telephony signals whose frequencies are well known, thus these interferences can be possibly processed and removed. In this research two SDR products (Realtek software defined radio RTL-SDR/Universal software radio peripheral USRP N200) are used to detect PD signals emitted by a PD source that was located at a distance of 1 m in case of RTL-SDR device while in case of USRP N200 the PD source was located at a distance of 3 m. These PD signals once received by an SDR device are recorded and processed offline in order to localize the PD source. The detected PD signal was around 20 dB above background noise in case of the RTL-SDR device and 25 dB above background noise in case of using the USRP N200. Selecting the appropriate SDR device depends on factors such as high sensitivity and selectivity. Furthermore, although USRP N200 is more expensive than RTL-SDR dongles, USRP N200 was preferred over RTL-SDR as it demonstrates higher sensitivity and overall better results. PD detection using SDR devices was conducted in the frequency domain. These result were validated using a high-end costly device, i.e. spectrum analyzer. Generally, SDR devices demonstrate satisfactory results when compared to spectrum analyzers. Considering that spectrum analyzers cost around £10,000, while a USRP N200 SRD device costs less than £1000, SDR technology seems to be cost-effective. Following PD detection, PD localization was performed using USRP N200 results, and a localization algorithm based on Received Signal Strength (RSS) was adopted. The localization result was within a 1.3-meter accuracy and this can be considered as a relatively good result. In addition, and for the purpose of evaluating the proposed scheme, more experiments were conducted using another system that is based on radiometric sensors which is WSN PD system. The estimated error was 1m in case of using the SDR-USRP N200 system and 0.8 m in case of using the WSN PD system. Results of both systems were very satisfactory, although some results at the corners of the detection grid were not good and the error was higher than 3 meters due to the fact that the RSS algorithm performs poorly at corners. These experiments were used to validate both systems for PD detection and localization in industrial environments

Enhance productivity and net economic return by intercropping sunflower (Helianthus annus L.) with common beans (Phaseolus vulgaris L.) under drip irrigation

Intercropping represents ways of maximizing water use efficiency (WUE) for higher yields per unit of irrigation water applied. The field experiments were carried out at the Experimental Farm of Arab El- Awammer Research, Station, Assiut during the two successive growing summer seasons of 2017 and 2018, to study the effect of different irrigation regimes (120, 100 and 80% ETo) and intercropping systems (sole sunflower, sole common bean and intercropping sunflower and common bean) for enhanced productivity and net economic return under drip irrigation. Irrigation with 120% ETo treatment gave higher yield and its compounds and oil % compared to 100 and 80% ETo treatments for sunflower and common bean. The highest stem, head diameters and 100-seed weight and seed and oil yield produced with sole sunflower as compared with intercropping of sunflower with common bean which had the lowest values in both growing seasons. The highest values of IWUE (0.723 and 0.704 kg/m3) were obtained at intercropping under irrigation with 100% ETo. Values of land equivalent ratio of various intercropping systems were larger than one in the intercropping systems. Sunflower + common bean cropping system produced higher values of net return than sole sunflower and sole common bean. The highest net return (2709 US$/ha) were obtained when irrigated sunflower + common bean intercropping system with 120$/ha) were obtained when irrigated sole sunflower with 80% ETo treatment in the first season. DOI: http://dx.doi.org/10.5281/zenodo.376327

STR-862: APPLICATION OF 4D AND 5D BIM IN COLD-FORMED STEEL RESIDENTIAL BUILDINGS

Traditional residential building systems are not sufficient to produce the required number of housing units needed every year to solve the current housing problem in many countries. To meet such a challenge, it is necessary to explore the latest construction technologies, and to create innovative building systems that have the potential to bring high-performance affordable housing within reach of new markets. Light (cold-formed) steel (CFS) framing systems have proven to be a worthy alternative to traditional systems. Recent advances in the application of Building Information Modeling (BIM) into the Architecture-Engineering-Construction industries present an additional mean to further enhance the efficiency of CFS projects. This paper presents a BIM based integrated approach for project scheduling and cost estimating of cold formed steel residential buildings. The approach integrates the basic 3D BIM model with the construction management tools used for project scheduling and cost estimation to produce a 4D BIM and 5D BIM models that can be used to enhance the project efficiency in both the design and construction phases. The developed models facilitate communication among all project participants and support project management in effectively planning on-site construction activities. A case study is presented to demonstrate the methodology

An Efficient Algorithm for Partial Discharge Localization in High-Voltage Systems Using Received Signal Strength

The term partial discharge (PD) refers to a partial bridging of insulating material between electrodes that sustain an electric field in high-voltage (HV) systems. Long-term PD activity can lead to catastrophic failures of HV systems resulting in economic, energy and even human life losses. Such failures and losses can be avoided by continuously monitoring PD activity. Existing techniques used for PD localization including time of arrival (TOA) and time difference of arrival (TDOA), are complicated and expensive because they require time synchronization. In this paper, a novel received signal strength (RSS) based localization algorithm is proposed. The reason that RSS is favoured in this research is that it does not require clock synchronization and it only requires the energy of the received signal rather than the PD pulse itself. A comparison was made between RSS based algorithms including a proposed algorithm, the ratio and search and the least squares algorithm to locate a PD source for nine different positions. The performance of the algorithms was evaluated by using two field scenarios based on seven and eight receiving nodes, respectively. The mean localization error calculated for two-field-trial scenarios show, respectively, 1.80 m and 1.76 m for the proposed algorithm for all nine positions, which is the lowest of the three algorithms

Partial discharge detection and localization : using software defined radio

Partial Discharge (PD) occurs when insulation containing voids is subjected to high voltage (HV). If left untreated PD can degrade insulation until, eventually, catastrophic insulation failure occurs. The detection of PD current pulses, however, can allow incipient insulation faults to be identified, located and repaired prior to plant failure. Traditionally PD is detected using galvanic contact methods or capacitive/inductive coupling sensors. This article discusses the use of Software Defined Radio (SDR) for PD detection and localization, and presents proof of principle experimental results that suggest SDR can provide a simple and reliable solution for PD-based monitoring of HV insulation integrity