In this paper, two fiber Bragg gratings (FBGs) sensors, which are based on different palladium (Pd) coatings ratios, was proposed to detect the dissolved hydrogen gas content in transformer oil. The FBG samples were prepared using a physical vapor deposition technique. Two samples were prepared with different Pd coating compositions. The first sample was coated with 100% Pd (Pd100), and the second sample was coated with mixture of Pd chromium (Pd58Cr42) that has a ratio of 58:42. Pd100 sensor showed faster response to dissolved hydrogen than the Pd58Cr42 sensor. In addition, the Pd100 sensor exerted higher strain at lower dissolved hydrogen content to the FBG compared with the Pd58Cr42 sensor. The Pd100 sensor has higher sensitivity, and the response range is limited to lower hydrogen content. This paper has showed the potential of using alloy like chromium to the Pd metal to enhance the dissolved hydrogen detection range.

Fiber Bragg Gratings Hydrogen Sensor for Monitoring the Degradation of Transformer Oil

Solution-controlled hydrogel coated materials for oil/water separation have been successfully fabricated. The as-prepared mesh can switch between superhydrophilicity/underwater superoleophobicity and superhydrophobicity/superoleophilicity through self-assembly and dis-assembly pathways. The PDMAEMA hydrogel coated mesh is firstly prepared via photo induced free radical polymerization. A facile monolayer electrostatic self-assembly method was involved by immersing the hydrogel coated mesh in an ethanol solution of stearic acid for a few minutes. The stearic acid modified mesh converts to superhydrophobicity/superoleophilicity. More importantly, the mesh can return to the original state swiftly after the dis-assembly of the monolayer by immersion in a NaOH aqueous solution. The unique superiority of this material is that the transition of wettability can be achieved in situ, so that oil and water can pass through the mesh in sequence through the control of the NaOH solution. Therefore, the as-prepared meshes have great potential in practical applications dealing with both water-rich and oil-rich oil/water mixture separation with high separation efficiency (>99.3%). The synthetic method is simple, time saving and cost saving.

A novel solution-controlled hydrogel coated mesh for oil/water separation based on monolayer electrostatic self-assembly

Distribution network experiences distinct changes from low to high load level every day. Electrical power losses in distribution systems correspond to about 70 percent of the total losses in electrical power systems. One of the most severe problems faced is power loss during the operation of transformer. Transformer plays a vital role in transmission and distribution system. There are many problems associated with power loss in transformer but this paper mainly focuses on efficient cooling system designed for overcoming heating and insulation losses. With the implementation of smart grid and smart cities, the traditional control mode of transformer's cooling system cannot meet the new demand. Ideally PLC is used for online monitoring and data recording. In our paper, we have proposed an intelligent cooling system based on Programmable Logic Controller (PLC) which eradicates the problem of manual transformer cooling control system by automatically switching between the cooling banks. The cooling system in our paper comprises of three cooling banks, each having a fan and a pump. At a time, two out of three cooling banks will be operating. In case of failure of any one of the operating banks, the third bank will automatically switch on in place of the faulty bank. Hence third bank will continue to operate until faulty bank is repaired. This switching between cooling banks is PLC controlled and thus eradicates the errors caused by human intervention. Along with this, continuous monitoring and data recording is simultaneously done. We have also focused upon proper utilization of standby bank by means of periodic switching. PLC logic is used for controlling all the components which are involved in the protection of transformer and also using the component only when needed eradicates the wastage of power and unnecessary operations. Human Machine Interface (HMI) can also be used for complete visualization of the process in the control room.

Intelligent PLC based transformer cooling control system

The main purpose of this work is to design and implement a PLC-based control system framework for the beer fermentation process. Firstly, the technological process of beer brewing production is analyzed briefly. Furthermore, the details of the control demand for beer fermentation process are introduced as well. On the basis of actual beer production projects in breweries, this paper investigate automation system and intelligent algorithms applied in the beer fermentation process. More specifically, it discusses the design and implementation of a proposed platform to remotely monitor and control SIMATIC PLC-based beer brewing production processes by using the industrial Ethernet network. Then, a set of integrated automatic control system for beer fermentation process and corresponding human machine interface (HMI) platform are developed using Wonderware InTouch configuration software successfully. In summary, it is a valuable exploration and attempt to apply automation technology to the beer fermentation process. This work has very obvious practical significance to the traditional beer production industry.

Design and implementation of control system for beer fermentation process based on SIMATIC PLC

Two-dimensional evaluation model of electrical equipment based on combined weighting and rating algorithm

Aiming at the problems of the traditional transformer cooler's control system, the paper developed the intelligent control system of the transformer cooling based on the DCS dual PLC. The DCS and dual PLC's redundancy, the intelligent motor controller, the system's centralized monitoring platform, and the environmental control system achieve the monitoring, controlling and remote status monitoring for the transformer cooling system, and improve the reliability and adaptability of the transformer cooling system. They can be suitable for the intelligent electricity grid. The technology is in the leading domestic level because of innovation in the high-performance distributed bus, the integrated design of three-phase solid state relay and magnetic latching relay and the PLC cooling mode using semiconductor refrigeration.

Intelligent Control System of Transformer Cooling Based on DCS and Dual PLC

Aiming at the subjective limitations of the traditional condition monitoring and evaluation methods for the power transformer, the condition assessment method of the transformer state based on the dynamic gray target theory is used to evaluate and diagnose the operating condition and the fault mode of the transformer. The probabilistic reasoning mechanism based on the distance measurement is constructed, and the electrical testing data and the oil chromatography analysis data are fused. That improves the credibility of the transformer's condition evaluation and fault diagnosis. The transformer's condition assessment simulation system is developed to achieve the measurement control of the transformer's partial discharge, the measurement control of the core's grounding current, the measurement control of the gas and micro-water in oil, and the measurement control of the oil temperature. On this basis, the evaluation results can accurately reflect the health state in the functional units of the transformer and the overall, so as to predict and prevent the faults, arrange reasonably the maintenance planning and focus.

Research on Condition Monitoring and Evaluation Method of Power Transformer

The detection and fault identification of the partial discharge is the important aspect for the monitoring of the power equipment. For the lacks of the traditional detection methods, this paper analyzed the UHF signal characteristic parameters of the power equipment’s partial discharge, and developed the UHF detection system of the partial discharge. The A/D technology of the gain equalization and quantization in the different bands is studied, and the fault diagnosis strategy of the partial discharge based on the UHF and AE is proposed. On the premise to ensure the integrity of the partial discharge signals, the acquisition, amplification, analysis and storage of the partial discharge signal is realized. The case-based reasoning technology determines the fault type and fault degree of the partial discharge to make the accurate judgment for the operational state of the equipment and improve the intelligence level and the operational reliability for the state diagnosis of the power equipment. DOI : http://dx.doi.org/10.11591/telkomnika.v12i2.4327

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Study on Monitoring System for Partial Discharge of Electrical Equipment

From the physical characteristics of the partial discharge, this paper analyzed the UHF signal’s characteristic parameters for the partial discharge of the power transmission equipment, used synthetically the detecting technology which combines the ultra high frequency (UHF) and the acoustic emission (AE), and established the online monitoring system for the partial discharge of the power equipment. On the premise ensuring the integrity of the partial discharge signal, the acquisition, amplification, analysis and storage of the partial discharge signal are implemented. The case-based reasoning technology determines the fault type and fault degree of the partial discharge to make the accurate judgment for the operational state of the equipment and improve the intelligence level and the operational reliability for the state diagnosis of the power equipment. The structural optimization design of the power transformer makes the no-load loss down by 50%, and the load loss down by 15%. That improves greatly the mechanical and electrical properties of the transformer.

Study on the Online Detecting Technology for Partial Discharge of Power Equipment with Mechanical Properties

The detection and fault identification of the partial discharge is the important aspect for the monitoring of the power equipment. For the lacks of the traditional detection methods, this paper analyzed the UHF signal characteristic parameters of the power equipment’s partial discharge, and developed the UHF detection system of the partial discharge. The A/D technology of the gain equalization and quantization in the different bands is studied, and the fault diagnosis strategy of the partial discharge based on the UHF and AE is proposed. On the premise to ensure the integrity of the partial discharge signals, the acquisition, amplification, analysis and storage of the partial discharge signal is realized. The case-based reasoning technology determines the fault type and fault degree of the partial discharge to make the accurate judgment for the operational state of the equipment and improve the intelligence level and the operational reliability for the state diagnosis of the power equipment.

Dong Xie

Papers

Intelligent Control System of Transformer Cooling Based on DCS and Dual PLC

Research on Condition Monitoring and Evaluation Method of Power Transformer

Study on Monitoring System for Partial Discharge of Electrical Equipment

Study on the Online Detecting Technology for Partial Discharge of Power Equipment with Mechanical Properties

On-Line UHF Monitoring System of Partial Discharge for Electrical Equipment