Guan Zhicheng's research while affiliated with Tsinghua University and other places

Publications (43)

Conference Paper
Composite insulators were extensively applied in outdoor insulation for the extraordinary performance of hydrophobicity and anti-aging property. Whereas HTV silicone rubber had low elastic modulus and the stiffness was not high enough to resist high speed wind. In northwest China there are many storm-wind areas where the designed wind velocity of t...
Conference Paper
During the pollution flashover process, streamer discharge is a very important stage before arc formed. In the paper measured the streamer propagates between two parallel plane electrodes by using three-electrode structure, and compared the characteristics of propagation while contamination with different ESDD and NSDD was brushed on the insulator...
Conference Paper
In order to evaluate the operating characteristics of RTV anti-pollution flashover coatings used in Guangdong Province, a series of experiments and tests were carried out on RTV coatings operating in different natural environments with operating periods ranging from 3 years to 8 years. The research results showed that the appearance of coatings wer...
Conference Paper
Defects of high-voltage transmission lines are often accompanied with corona discharge; and corona discharge would produce ultraviolet. Based on this principle, the UV imager can be used in detecting the defect. Electric field strength is the main factor affecting the corona discharge, which is determined by power-supply and experimental model. In...
Article
Icing problem is a very significant hidden danger that influences the safely work of insulators and transmission lines, especially in 2008 the icing caused very big disaster. Several surface treatments were used to prevent the ice formation, such as superhydropobic surface, electric heating coatings and photothermal type coatings. But these treatme...
Article
This paper descirbes leakage current characters and discharge phenomenon of outdoor insulators both in the lab and in the field. The results are hoped to be used for online monitoring of the contamination levels. The following contents are introduced in the paper: leakage current monitoring systems, relationships between leakage current and dischar...
Conference Paper
Pulsed electric field is a novel non-thermal process technology. It could be applied in the extraction of functional components from plant for its irreversible disintegration on plant cell membrane. PEF treatment caused an irreversible disintegration on the cellular membrane of raspberry cell and the extraction yield of anthocyanins from raspberry...
Article
High voltage equipments, especially polymer insulators may be getting into aging conditions due to the existence of corona discharge on the surface after a long term of running, which would accelerate the deterioration of the surface insulation performance, and even make equipments step into calamity ultimately. So it is significant to detect coron...
Article
Loose stator slot wedges could result in excessive vibration of the stator coils in large generators, which would accelerate the deterioration of the groundwall insulation and even eventually lead to catastrophic failure of large generators. So it is significant to detect loose slot wedges in stator slots to ensure generatorpsilas normal operation....
Conference Paper
HV outdoor insulating systems such as line and station insulators, surge arresters and bushings, using silicone rubber for outdoor insulation have become very popular. This paper presents the mechanical behavior and electrical behavior of silicone rubber blend with different fillers. Various loadings of alumina trihydrate (ATH) and silica are added...
Conference Paper
Contamination flashover is one of the most serious problems in power delivery system. Leakage current that flows over the surface of the contaminated insulators is considered the main causation of this problem and a lot of researches have been carried out to study the characters of it. But the relationships between leakage current characters and re...
Conference Paper
Using a high-speed camera, the fundamental behaviors of arcs on the surfaces of two types of 300 kN porcelain insulators were studied under DC voltages. The test results showed that it was quite easy for the arcs on porcelain insulator surfaces to levitate from insulator surfaces in high altitude areas (1970 m). The influence of angles, used for di...
Conference Paper
It has been investigated that the effect of relative humidity on statistical parameters of negative corona pulses at different air pressure conditions. A rod-plane electrode configuration has been used. The range of air pressure and relative humidity is 0.06 MPa~0.10 MPa and 30%~90% respectively. The variation of average amplitude and standard devi...
Article
Summary form only given. Nonthermal atmospheric plasma which can be produced by dielectric barrier discharge (DBD) has many applications in textile surface modification, which demands highly on the uniformity of the DBD. Based on the experimental setup in our laboratory, gas flow was found to be a very important factor to influence the state of the...
Conference Paper
To prepare uniform nanofibers from poly (ethylene oxide) (PEO), a voltage of 0 to 15 kV was applied to a distance of 15 cm to 30 cm between tip and ground collector. In this study, jet current and Taylor cone were used to express the electrospinning stability. It is showed that an electric current during electrospinning affects the fiber morphology...
Conference Paper
Electrospinning is a subjecting of a fluid jet to a high electric field process, by which polymer fibers with nano-scale diameters lower than 100 nm are formed. Significant progress has been made in this area throughout the past few years and this technology has been exploited to a wide range of applications. However, the efficiency is still very l...
Chapter
This chapter presents the influences of annealing method on the space charge properties in low-density polyethylene (LDPE). LDPE films are prepared by three kinds of annealing methods, which are different in cooling velocity. The crystallinity of the LDPE samples are measured and compared. Surfaces of samples are observed. Higher cooling velocity r...
Chapter
This chapter presents the influences of annealing method on the space charge properties in low-density polyethylene (LDPE). LDPE films are prepared by three kinds of annealing methods, which are different in cooling velocity. The crystallinity of the LDPE samples are measured and compared. Surfaces of samples are observed. Higher cooling velocity r...
Conference Paper
Room temperature vulcanized (RTV) silicone rubber (SIR) coatings are used increasingly on outdoor HV porcelain and glass insulators and bushings when subjected to heavy pollution. An important property of the RTV-SIR coating is its ability to restore the hydrophobicity of the surface after a layer of contamination has built up on it, and thus conti...
Conference Paper
The 750 kV alternating voltage of transmission lines plan to be built in the northwest of China, where the altitude is from 1800 m to 2800 m, and the climate is very serious. In the design of the lines, we contrast the ability against the pollution flashover of the post insulators. For three types of typical high intensity, big diameter post insula...
Conference Paper
In this paper, model of composite insulators were designed to study distortion, movement of the water droplets when discharging occurs on the shed surface of composite insulators applied with uniformity electric field. The distortion and movements of single and multiple water droplets on the surface of insulator in ac and dc electric fields were st...
Conference Paper
The room temperature vulcanizing (RTV) silicone rubber coating on the surface of insulator may increase the flashover voltage of contaminated insulators, which is designed to replace greasing and cleaning of insulators. The RTV silicone rubber coatings have been used in China to prevent pollution flashover of insulators due to their long service li...
Conference Paper
The lightning electromagnetic environments of planned Zhongguancun Software Park near transmission lines, including electrical field, magnetic field and grounding potential rise, are assessed by numerical analysis. From this analysis, we can conclude that the lightning strike is a serious threaten to the software park, protective countermeasures sh...
Conference Paper
The electromagnetic coupling between the control cable with metal shielding sheath and metal conductor of grounding grids in the substation of a power system threatens the safe operation of an electronic system connected with the control cable. In order to simplifying the electromagnetic coupling analysis of this system, the core-sheath model of a...
Conference Paper
The use of room temperature vulcanized (RTV) silicone rubber (SIR) coatings for improving the contamination performance of existing ceramic insulation has become popular. RTV SIR coatings work on the principle of providing a high surface resistance even in the presence of moisture and contamination, hence, limiting the leakage current to harmless l...
Conference Paper
The loss of surface hydrophobicity of room temperature vulcanized (RTV) silicone rubber (SIR) due to immersion in acid, alkali and saline solutions has been studied as a function of immersion time and concentration. The loss and recovery of the hydrophobicity is correlated with the solute and the absorption of water during immersion and its subsequ...
Article
In this paper, results of a survey, intended to evaluate the hydrophobicity status of SIR insulators in various polluted areas, is firstly reviewed. Following the investigation, mechanisms related to hydrophobicity transfer and recovery of SIR insulator were studied in depth. It was found that the hydrophobicity transfer or recovery is actually an...
Conference Paper
The usage of silicone rubber insulators in various contaminated areas has increasesd prominently and still keeps rising. In the case of China, more than 90% of the 800000 composite insulators are operating in heavy or medium pollution environments. As the exposure time in the field is prolonged, the change of hydrophobicity and the build-up of poll...
Article
More and more high voltage transmission lines make use of rubber housed ZnO arresters in series with another air gap (for example, the insulator gap) as lighting protection elements. Many test results of ZnO arresters protection performance show that this insulation arrangement is suitable for practical lines according to results based on only simp...
Article
This paper analyzes the different discharge processes occurring at normal temperatures and high temperatures. The theoretical results show that the net charges in the streamer channel at normal temperatures are zero, but they are positive at high temperatures so that the advancing field is reinforced more than that at normal temperatures. Therefore...
Conference Paper
In this paper, the pollution regularity versus time and various weather conditions and the distribution of contamination on the surface of a porcelain insulator is discussed in detail using a partial surface conductivity method. The results illustrate that the self-cleaning ability of rain has a notable influence on the contamination of each kind o...
Conference Paper
Chang-Fang compact line is the first 500 kV compact line in China. Phase to phase composite spacer is one of the key elements of this compact line. There are two special technical requirements, mechanical characteristics and electrical behavior, in the design of the spacer. In this paper, the mathematics model about the conductor movement system an...
Conference Paper
Wet tests, dry tests and artificial pollution tests were carried out to investigate the influence of shed profile and shed arrangement on the outdoor insulation performance of polymeric insulators. The sample insulators characterized almost the same insulation distance but prominently different shed diameter and shed space, therefore various leakag...
Conference Paper
Considering various contaminated environments in the field, research on the hydrophobicity transfer properties of different pollutants is necessary for the proper selection and maintenance of polymeric insulators. In the paper, hydrophobicity of SR polluted by several kinds of pollutants such as kieselguhr, kaolin, Tonoko, metal oxides and inorgani...
Conference Paper
The conductor-conductor gap is a practical operation parameter in transmission lines. In the past, the insulation distance between conductors was determined only by a simple impulse voltage. But for compact lines, a more precise model of sparkover characteristics should be studied in detail. In this paper, the influence of a pre-stressing AC and fl...
Article
The development of composite insulators in China dates back to the early 1970's. In the 1990's they have become widely used in China. At present, up to 600000 composite insulators are operating on 35 to 500 kV ac overhead transmission lines. They are to be introduced into the 500 KV HVDC transmission schemes. In China all composite insulators in se...
Article
The development of composite insulators in China dates back to the early 1970's. In the 1990's they have become widely used in China. At present, up to 600000 composite insulators are operating on 35 to 500 kV ac overhead transmission lines. They are to be introduced into the ±500 kV HVDC transmission schemes. In China all composite insulators in s...
Conference Paper
Brittle fracture of composite insulators occurred in China makes it a subject of concerned for many people, and it is urgently necessary to put forward a test method on the resistance of FRP cores against stress corrosion. The brittle fracture caused by stress corrosion is simulated in two similar ways. The fracture modes are analyzed, and the meas...
Conference Paper
In this paper, three reasons for the excellent contamination-flashover resistance of SR composite insulators are put forward, and their reasonability are proved with the mathematical contamination flashover model
Conference Paper
There is a large area at high altitude in China where it is necessary to build high voltage transmission lines and substations. Studying the discharge characteristics of several important types of electrical field is a very important topic in the development and building of power systems in a high altitude area. In this paper a series of tests have...
Conference Paper
The leakage current of a polluted insulator not only depends on pollution degree and damped situation, but also depends on insulator shape, insulator string length, operation voltage etc. This paper studies the relationship between the leakage current and factors such as the pollution degree, the damped state of contamination, the shape of insulato...

Citations

... The composite insulator is an important component in the power system, which plays a crucial role in electrical insulation and mechanical support [1]. Silicone rubber (SR), due to its excellent mechanical and insulation properties, has become the main material of sheath and housing of composite insulators. ...
... Glass insulators are superior to porcelain insulators and there is no string breakage even under a blast circumstance, which greatly reduces the maintenance costs. However, during long-term operation, the glass insulators that may blast under severe weather conditions will increase the instability of the transmission lines [7,8]. Therefore, it's of great significance to detect the self-blast state of the glass insulators. ...
... Removing the aged RTV coatings is also a problem when maintaining insulators, Wang Xilin et.al. proposed a solution to this problem [9,10]. The application methods of coatings are mainly brushing, spraying and dipping [11]. ...
... Over time, the coating may lose its hydrophobic property and lead to flashover [10,11]. Amongst the family of polymeric insulating materials, RTV-SiR has shown superior hydrophobicity, leakage current suppression, temperature resistance, UV resistance, and high flame retardancy [12,13]. The RTV-SiR due to its molecular structure has the hybrid nature of rubber as well as inorganic nature [14]. ...
... Assuming usage of sensitive detectors, they are successfully applied for detecting PD and locating their source [19,20]. Another non-invasive method for PD detection is the optical method, which includes recording of visible light and UV radiation using specially developed detectors, video cameras or optical spectrophotometers [21][22][23][24][25][26][27][28][29][30]. All effects accompanying electrical discharges are the effect of energy transformation and are included in the power balance of this phenomenon. ...
... From the photographical records the actual spark length was estimated between 1.05 and 1.22 times longer than the gap length. As the investigated gap is very short in length, the significantly longer actual spark lengths could be attributed to possible surface charging related to intense partial discharge activity [13], [16], [17]. ...
... e insulator's condition could be classified by measuring the leakage current on the surface [1][2][3]. Many studies have been developed to predict the insulator leakage current by employing neural networks and meteorological data [4][5][6][7][8][9][10][11][12][13]. Zhicheng et al. have proved the strong correlation between leakage current and other meteorological data, such as humidity and rainfall. ...
... In 2008, Jia Zhidong, Gao Shengqiang, and others of Tsinghua University developed a portable detection system based on the theory of Digital Signal Processor (DSP) embedded system. In the test, it was found that it is more convenient to detect loose slot wedges than traditional detection methods [5]. In 2009, Peng Xiang, Jia Zhidong, and others used 300 MW of generator samples produced by the Beijing Steam Turbine Generator Company to build a model of the generator stator trough wedge structure. ...
... As previously referred, the LMW components penetrate into the surface pollution layer, changing its behavior from hydrophilic to hydrophobic. In fact, the LMW components are absorbed by the surface layer of soil, characterized by the higher surface energy than that of the material [31]. Specifically, the higher the energy difference between the pollution layer and the material, the stronger the LMW molecules absorption from the pollutants. ...
... The coefficient of correlation supports the statement, giving a value of −0.98. Several authors worldwide have investigated the high correlation between the magnitude of the leakage current and the weather [17,[25][26][27][28][29][30]. Once more, this relationship is confirmed. ...