File Name: simulation and fault analysis of hvdc on matlab .zip
The system considered in this book is given in Fig. In this chapter, the steady-state and transient behavior of control schemes in normal and fault conditions a VSC-based HVDC connected to a grid is studied. It is that the control scheme that uses is vector control and hysteresis current control.
- ANALYSIS OF FAULTS ON MONOPOLAR HVDC TRANSMISSION LINE
- Simulation and Fault analysis of HVDC on MATLAB
- Simulation and analysis of faults in high voltage DC (HVDC) power transmission
ANALYSIS OF FAULTS ON MONOPOLAR HVDC TRANSMISSION LINE
Show all documents Modelling of Ultra High Voltage Transmission Line Faults Detection and Identification by Using Matlab Simulation The main advantage of the transform wave is that the analysis and detected be fine adjusted so that high frequency components and low frequency components can be detect and identified precisely.
Results obtained from the transmission line wavelet transforms are shown on the time domain and the frequency domain. The High transmission line wavelet transform has to be a change in detect and identified scale by the factor is called discrete wavelet transform . These faults canbe identified, analysis and classified has to used discrete wavelet transform. When during the fault are occurs, the grid voltage and grid currentundergoes transients waveform.
The transient waveform is identified and analysis by usingdiscrete wavelet transform and the different fault can be classified . After wavelet transform calculating the energy of highest waveform of fault associated to each phase and ground and thus the fault involving phase is identified. When different fault are occurred two or more conductors come in contact to each other or ground in three phase systems, for it is at such times that the electrical power system components are the greatest stresses from excessive currents.
When there a major fault which occurring on long transmission lines not only effects the all equipment and it also effect the electrical power quality. So, it is necessary to determine the types of fault and location of fault on the transmission line and clear the faults as soon as possible in order not to cause some damages. A flash over, lightning strikes to birds, wind, snow and ice load lead to short circuits. When the deformation of insulator materials are also to occurs a short circuit faults.
Thus it is essential to detect and analysis the fault quickly and separate the faulty part of the EHV transmission line. We find out the ground faults quickly they are more important for safety, economy and electric power quality. Now this transient wavelet or waveform based fault analysis, detect and compare the faults levels of wavelets of each phase and zero sequence currents and thus detecting and classifying the faults.
Figure 1 shows the block diagram of EHV transmission line fault . The ANN Based distance relay which can differentiate the fault conditions from normal operating conditions.
The Artificial neural network technique allowed us to analyse the performance of relay at various faulted condition and Produced a trip signal if a fault is generated and no trip Signal otherwise. In this paper feed forward neural network is developed in MATLAB using supervised training and delta learning rule for obtain the best Performance of the relay.
The simulation result shows that the proposed scheme is able to identify all the faults on transmission line with great selectivity, reliability and sensitivity. Control system was modelled and disturbances are set in to ascertain the performance of the system. The converters are pulse and are interconnected through km line and 0.
The harmonic filters act as a source of filter for AC and reactive power compensator for DC. Several tests were carried out and the result was used to check the waveform and variations of voltage and current obtained from variations of generator source voltage. Results presented demonstrated that controller performance in recovery of HVDC links from various disturbances is possible. Robot for High Voltage Transmission Line Inspection he inspection of high voltage transmission line is a very risky operation, as workers move on the lines several tens of meters above the ground, in very demanding and stressful conditions.
The helicopters are used as a way to improve safety and speed of inspection operations. Even though video shot from the cameras placed on the helicopters provides general information regarding the conditions of the lines, and most importantly the vegetation around the towers and lines, this method cannot provide details of the lines regarding scratches or minor faults or corrosion, these are early signs of problems that should be repaired before the lines are seriously damaged.
Generally EHV and UHV line will be longer enough to give Distance protection to clear any type of fault in the line with numerical relay within ms using scheme communication. But single phase faults can be high resistive in nature and frequent also.
Distance protection fails even if fault resistance is equal to load resistance. But delayed trip in kV and above systems is generally not a good practice because of higher voltages in healthy phases with HRF in one phase. This testing is carried out for a disturbance took place in a kV transmission line HRF where Distance protection failed to clear the fault instantaneously. The results obtained shows that that three phase test system model in presence of the STATCOM has been able to improve the voltage stability of the power system.
Fault Detection and Classification in Transmission Line by using Support Vector Machine Technique Consider there are two linearly separable classes, each containing two instances as shown in Fig.
Now there are many possible ways to select a hyperplane from given options. Note that for two dimensional example separation is done by a line and for multidimensional, it is a hyperplane. Here line is stated as hyperplane for generalization. All hyperplanes are eligible for classification of four instances into two classes. Most appropriate and accurate hyperplane must be selected so as to classify any other complicated instances.
Support Vectors are the data points or instances that lie closest to the hyperplane. In green hyperplane, both instances from different classes are closer to green hyperplane.
SVM focuses on large margin separation classification, therefore most accurate hyperplane according to SVM technique is dashed black hyperplane.
This hyperplane has maximum width from the instances of opposite classes. Among them, the Transmission lines are one of the most important parts of the system. Faults occur in transmission lines have high impact on the electrical power system.
The major fault in transmission line is single line to ground L-G fault, but, various types of faults also occur in transmission line , such as unsymmetrical faults which includes single line to ground L-G fault, double line to ground L-L-G fault and line to line L-L fault and symmetrical faults which are three phase fault.
So, the protection relays are needed to protect transmission lines from various types of faults. Overcurrent and earth fault relay is normally used to protect transmission lines, distribution lines, transformers and bus coupler etc. Moreover, these relays can be used as main or backup protection. The modeling of protection relays is required to determine the effects of network parameters and configurations on the operation of these relays. The study of test system is Paunglaung — Pyinmana High Voltage transmission line.
The proposed model was tested for single line to ground L-G fault and three phase fault witha fault resistance 0. To avoid this problem we want to investigate performance of zig zag transformer as DC injector in main AC system.
The saturation of transformer due to flow of dc current can be avoided by using zigzag connected winding at both ends.
The windings of zigzag transformer are differentially connected. The fluxes produced by the dc current flowing through each winding of the core of a zigzag transformer have equal magnitude and opposite in direction and hence cancel each other so that the net dc flux becomes zero. Thus, the saturation of the core due to dc current is removed. It is shown that the detection performance becomes better when increases However, when turns to 48, the performance detection declines.
Therefore, should be relatively small while using this technique for a given number of samples. Therefore, choosing a proper temporal smoothing factor for a given number of samples is important. Figure 3 shows the performance comparison of the optimal- detection technique, the MED detection and energy detection. In MED detection , 4 receiving antennas are used for sensing in the radio environment while the optimal detector has a temporal smoothing factor of In this proposed work, one additional output value was used, so as to find the fault location is determined concurrently with the fault type.
We use minimum training input and output sets to train the network for every fault in each standard. Also a separate network was trained for each fault. The epoch max should be sufficiently large to. Low Frequency Induction Simulation of Power Transmission Lines and Pipelines: A Comparative Study A comparative study of the Carson, Ametani and Lucca mutual impedance approximations used for the computation of induced open circuit potential on pipelines is presented.
The study also affirms a strong relationship between the induced open circuit volt- age profile produced by Lucca and Ametani formula for the different power line configurations studied.
Although this can somewhat be noticed in the formulae. The sta- tistical analysis results presented revealed a strong rela- tionship between the Lucca and Ametani approximation, even for the different power line configurations. There- fore, care must be taken in selecting a mutual impedance formulation when computing the induced potential on metallic pipelines. This is to avoid overestimation or underestimation of the induced voltage. Also, measure- ments can be made if possible to support the results of any computational approximations used.
Due to the long distance transmission of the generated power the power system becomes complex. That is why HVDC transmission system used for long distance carriage of power. During transmission of HVDC system protection and security of the system is compulsory in order to minimize the overall losses.
This review paper discusses the protection of HVDC line based on transient energy and transient power. The fault which is occurred on the system reflected on three main parts of the system. Using modified traveling wave algorithm the transient parameters are determined and the type and location of fault can be detected. The objective of the training process is to adjust all ANN weights and biases to obtain minimal deviations between the target and calculated ANN outputs in relation to the mean value of all input samples.
Once the training process is completed the results of training must be checked, first using the samples used in training and then new samples not used in training.
To implement a neural network, the following steps must be taken, selection of a suitable network architecture; selection of the learning rule best suited to the network established; training of the neural network; checking of network behaviour. Fault location approach using ANN The basic points of the procedure used to implement neural network in the fault location process in single, two-terminal transmission lines. Measuring of Voltage signal is done on the bus B2 of the given test system.
Voltage signal is decomposed using Stockwell transform. From fig. Hence, the detection of LLG fault is done effectively with the help of proposed fault index which is based on the median. This paper compares the two different inverters and it is to be suggested that PWM inverter is best suited as per THD analysis. Distance relay protecting series compensated line has limitation with metal oxide varistor MOV operation, high resistance fault, prefault system condition and shunt capacitance.
In this paper, a novel technique for the protection of transmission lines for line with fixed series compensation connected at one end using local measurement is proposed. The proposed system uses Discrete Wavelet Transform DWT which is widely used in recent times for power system protection. DWT is used here to extract the unseen factors from the fault signals by performing decomposition at different levels.
The spot of faults is carried out by obtaining the local fault information and remote location fault information along with the transmission line length. The system is independent of any statistical system data and has negligible fault resistance.
Test system is modelled in EMTP and fault signals are generated to test the reliability of the algorithm. The projected system promises the result by detecting, classifying and locating all the ten faults possible in the transmission line of the power system. A variety of fault cases and simulation results are introduced to show the effectiveness of such algorithm.
Simulation and Fault analysis of HVDC on MATLAB
Skip to search form Skip to main content You are currently offline. Some features of the site may not work correctly. DOI: Karthikeyan and Yew Ming Yeap and A. Karthikeyan , Yew Ming Yeap , A. Modern civilization depends heavily on the consumption of electrical energy for industrial, commercial, agricultural, domestic and social purposes.
The modern High Voltage Direct Current HVDC transmission technology depends on the development of power electronics based on the semiconductor devices. This paper represents a simple model of HVDC transmission system in which the converter and filter have been designed to increase stability of power transmission. Using this model, current - voltage C-V characteristics have been simulated for steady state condition. It has also been studied for different fault conditions. With the proposed strategy the HVDC system can provide useful and economical way to transmit electric power over the long distance, thereby improving the bulk transmission of electric power and power system stability. Open Journal Systems.
Simulation and analysis of faults in high voltage DC (HVDC) power transmission
Functioning of complex HVDC transmission system converter can be obtained by analytical modeling. Developing countries like India and China with their ambitious power capacity enhancement program are installing more HVDC systems for long distance transmission. More can be obtained from huge investments in complex HVDC systems if operation and maintenance personnel have deeper understanding about the functioning of these systems. The model also helps in understanding the role and importance of AC filters.
Documentation Help Center. The rectifier and the inverter are pulse converters using two 6-pulse thyristor bridges connected in series. The rectifier and the inverter are interconnected through a km distributed parameter line and two 0.