In the present work, a typical 400 KV double circuit transmissionline tower is considered, for optimizing the structure with respect to yield strength of the tower member as variable parameters. The tower is to be modelled and analyzed using STAAD.Pro V8i structural analysis software to obtain the optimum design of towers. The tower configuration is shown in table1 and figure 1. As per the guide lines of KPTCL , table 2 lists the details of some parameters typical to a 400kv double circuit suspension type tower and table 3 lists the details of some parameters of conductor and ground wire .Loads and Load combinations criteria on the ground wire, conductor and on the tower are found using IS:802 (Part 1/Sec 1)-1995
________________________________________________________________________________________________________ Abstract - The Transmissionlinetowers are one of the important life line structures in the distribution of power from the source to the various places for several purposes. The tower is designed for the wind zone V carrying 132 KV DC. Tower is modeled using constant parameters such as height, bracing system, angle sections, base widths, wind zone, common clearances, span, conductor and ground wire specifications. The loads are calculated using IS: 802(1995). After completing the analysis, the study is done with respect to deflections, stresses, axial forces, slenderness effect, critical sections and weight of tower. Using STAAD PRO v8i analysis and design of tower has been carried out as a three dimensional structure. Then, the tower members are designed.
Commonly used types of foundations in the transmissionline in permafrost regions are listed in this paper. Moreover, different types of foundations applicable for different frozen soil conditions are summarized. The fundamental principles of the selection of the type of tower foundation in permafrost regions are also listed. Except for making plans on the direction of lines in advance and escaping harmful geological areas, a careful surveying of frozen soil in the field is conducted initially. The purpose is to confirm the characteristics of permafrost. The appropriate tower foundation vis-à-vis the special properties of frozen soil must be selected and detailed. The application of proper design principles is necessary to determine the best foundation type.
This paper presents the design of a dual band branch line hybrid coupler(BLHC) with different power division ratios at two bands. In the proposed design, transmission lines of the BLHC are transformed to 𝜋𝜋 - type equivalent circuits which represent different impedances and λ/4 electrical length at two frequency bands. In order to verify the proposed method, a dual band coupler with different power division ratios is designed for 0.9 GHz and 2 GHz applications. The desired power division ratios are 1:1 and 1:3 at the two operating frequency bands. The measured results show excellent performance with an insertion loss of less than 0.33 dB, a return loss of less than － 18.07 dB, and good isolation characteristics.
The above named line is a short medium –voltage overhead transmissionline, being approximately 75 km long at 50Hz and 33KV in tension (SHEPHERED et al., 1970). This 150mm2 (Wolf) aluminium-conductors – steel – reinforced line has a resistance and a reactance of approximately 0.19 ohm/km and 0.34ohm/km at 50Hz and 200c, as determine from Tables. For short lines, of course, the shunt capacitance will normally be neglected, and the equivalent circuit of the line will then consist of a resistance in series with an inductive reactance .
Power line channel is a very harsh electronic communication media which poses a num- ber of challenges to communication system design. First, it is frequency selective due to signal reflections and transmissions caused by impedance mismatches at transmis- sion line discontinuities. Although physical behaviours of reflections and transmissions are well studied in transmissionline theory, statistical behaviours are not well charac- terised. Second, it exhibits high attenuation and strong low-pass behaviours which limit not only network coverage but also usable frequency bands. These two problems exist because transmission lines are not designed for transmissions of high frequency signals. Normally, due to complex network topologies and thin cables, indoor power line chan- nels present higher attenuation than outdoor channels. Third, it may be time-varying because of different kinds of network variations including change of topology, variation of loads and fluctuation of cable parameters. This is usually true for indoor power line channels due to the time-varying behaviour of electronic appliances. Apart from these, PLC systems are further impaired by coloured background noise and complex impul- sive noise. Therefore, extensive studies on channel characterisation and modelling are necessary for efficient utilisation of the channel.
sections were added to the conventional one. In , a dual frequency WPD was proposed using open ended stubs; unfortunately, a parallel combination of lumped resistor, capacitor and inductor was used in the design. In , a dual band WPD using planar artificial transmission lines was presented. Nevertheless, the existence of lumped elements (resistor, inductor, and capacitor) and design complexity is a major drawback of this kind of miniaturization. In [6, 7], dual-frequency Wilkinson power dividers were introduced. However, a parallel com- bination of a resistor, inductor, and capacitor was used for isolation between the two output ports. In , a dual band unequal Wilkinson power divider without reactive components was introduced in which open stubs were added to the conventional structure to achieve a dual band operation. In our paper here, a dual band compact WPD is designed and fabricated using non-uniform transmission lines (NTLs) theory . The design of NTLs is based on simple transmissionline theory as presented in the next section. Moreover, two lumped resistors are only used, without any capacitors or inductors.
smooth the plates are stuck together at the edges but the rest of each plate is continuing to move, so the rocks along the edges are distorted (what we call "strain"). As the motion continues, the strain builds up to the point where the rock can’t withstand any more bending. With a lurch, the rock breaks and the two sides move. An earthquake is the shaking that radiates out from the breaking rock. Unfortunately, timing of this natural phenomenon cannot be predicted scientifically. Historical records reveal the tendency of earthquakes to revisit regions after an interval of time. This random time interval is called RETURN PERIOD. This is the basis of the seismic conation. There are four zones in the country and they are denoted as II, III, IV and V. Zone I which existed in the earlier versions of the code, has been upgraded to Zone II or higher. The higher the zone, the more vulnerable is that region to a major earthquake. The size of an earthquake is measured by the strain energy released along the fault. It is expressed as MAGNITUDE. The commonly used scale for expressing the magnitude is the Richter scale. Every unit increase in magnitude implies an increase of about 31 times the energy. Dynamic analysis may be performed either by the Time History Method or by the Response Spectrum Method. For cases where a more refined design analysis is desired, response spectra are used as the means for determining lateral forces. A Response spectrum for a particular earthquake shows in a relatively simple way the dynamic characteristics of a given earthquake.
; The detection system collects the current added to the insulator through the current sensor. The CPU can analyze and calculate the resistance value of the insulator, and transmit the final detection result to the robot processing core STM32 through RS232. In this way, the resistance value of insulator string can be transmitted to the ground control terminal in real time. If the low value insulator is detected, zero value alarm can also be carried out, which is convenient for operation and maintenance personnel to handle. Due to the complex electromagnetic environment of UHVDC transmission lines and various leakage currents on insulators, it is necessary to filter clutter.
There are studies regarding ZigBee's performance based on theory and simulations such as [35, 36]. Hameed et al. in  put forward a scheduling scheme for guaranteed time slots for real-time applications, and in  Zeghdoud et al. obtained optimal throughput for different clear channel assessment modes in the presence of IEEE 802.11 interference. On the other hand, studies that examine transmission reliability for off the shelf ZigBee devices are scarce. Ilyas and Radha in  is one such study that investigated the error process in IEEE 802.15.4 devices for indoor and outdoor environments. Using transmission data, they collected and modelled the channel using the bit error rate (BER) probability density function and correlation coefficient. Industry is interested in the performance of ZigBee in different applications, such as in vehicles and in industrial settings like [38, 39] by General Motors, and General Electric and Sensicast Systems, respectively. These studies combined with this chapter's experimental results for several environments will give researchers an excellent foundation for ZigBee's ability to optimally perform in many real-time applications.
Flexible AC transmission system (FACTS) is a technology, which is based on power electronic devices, used to enhance the existing transmission capabilities in order to make the transmission system flexible and independent operation. The FACTS technology is a promising technology to achieve complete deregulation of Power System i.e. Generation, Transmission and Distribution as complete individual units. The loading capability of transmission system can also be enhanced nearer to the thermal limits without affecting the stability. Complete close-loop smooth control of reactive power can be achieved using shunt connected FACTS devices. Static VAR Compensator (SVC) is one of the shunt connected FACTS device, which can be utilized for the purpose of reactive power compensation. Intelligent FACTS devices make them adaptable and hence it is emerging in the present state of art. This paper attempts to design and simulate the Fuzzy logic control of firing angle for SVC in order to achieve better, smooth and adaptive control of reactive power. The design, modeling and simulations are carried out for λ /8 Transmissionline and the compensation is placed at the receiving end (load end).
Abstract—A new design of a wideband Wilkinson power divider using double-sided parallel strip line technique is presented in this paper. To obtain a good isolation value, the proposed design was integrated with three isolation resistors. The proposed power divider is designed for a wide range of frequencies between 2 GHz to 6 GHz with all the ports matched to 50 Ω. The conventional quarter wavelength arms are divided into three different widths to ensure wideband capabilities. Moreover, the novelty of the proposed design is illustrated from the double-sided parallel-strip line technique where proposed design is using similar structure at both the top and bottom layers to ensure balance of transmission. All dimensions for the transmissionline section were optimized to achieve wideband operation and were integrated with a lumped element. This design can be used as a double- sided feeder for a microstrip antenna.
Communication plays a significant role in any generation. And this generation is widely using wireless communication which is supported by communication towers spread across the nations. As usage of cells is increasing very rapidly, few towers are installed at the higher elevation and few are installed at the tall structures or apartments for proper communication. As cities have scarcity of land and lack of open free spaces, there are many more towers which will be installed on the existing buildings for good service. Even though research says there is little effect of radiation around the tower, there is another effect which is not seen currently as a great threat and that is the effect of building response because of telecommunication tower installation on building rooftop.
Recently, the advent of the new ferrites and amorphous glasses has revived an interest in magnetic pulse compression circuits (MPC)^ although their basic design has changed little over the years. They are capable of operating at repetition-rates of lOkHz and efficiencies of 85%3,4 ^nd are frequently used in laser discharge circuits, e.g. the Lambda EGM Series. They can also be scaled to high voltages. For example, the lOOkV modulator by Stockton^ called RAMESES I uses a magnetic switch to produce a 200ns pulse for a IQ coaxial water transmissionline and Comet^, the 6 MV 400 I/pulse accelerator uses one to generate a 23ns risetime pulse into a 2.16Q load. The problem with magnetic switches is that they cannot be used to produce output pulses with lisetimes less than a few tens of nanoseconds because there is still a significant amount of inductance present in a saturated magnetic switch.
IV. R ATE -3/2 N ON -O RTHOGONAL STB C ODE As was pointed out in section II, the 3-phase power line channel provides isolation between the transmission paths. Therefore, the inherent spatial orthogonality of this channel allows us to remove the restrictions imposed in the transmission matrix by the theory of orthogonal designs . In particular, it is now possible to trade off bandwidth for signal-to-noise-ratio. In other words, we are able to increase the symbol rate by reducing the achievable diversity order. In order to do this, however, the space-time block code has to be based on a non- orthogonal design. Consequently, in this section we present a new real non-orthogonal space-time block code with rate 3/2 and diversity order of 2. For a 4x3 transmission matrix like the one in (5), this is the maximum rate that can be achieved without completely losing the diversity gain provided by an STBC scheme. Denoting the new code by N r ( 3 ) , its transmission matrix is expressed by
It was always recognized that ac power transmission over long lines was primarily limited by the series reactive impedance of the line. Series capacitive compensation was introduced decades ago to reduce a portion of the reactive line impedance and thereby increase the power transmittable capacity of the line. Subsequently, within the FACTS initiative, it has been demonstrated that variable series compensation is highly effective in both controlling power flow in the line and in improving stability. Series Compensation (SC) in transmissionline introduces several problems like voltage and current inversion, sub-synchronous resonance (with mechanical system), ferro-resonance (with line inductance) and reaching problems (distance measurements). SC badly affects accuracy, selectivity and reliability of mho relay which leads to an unsecure power system. It is responsible for mal-operation of mho relays, particularly the reaching characteristic of the relay. In this project a new algorithm based on integrated impedance methodology is proposed to detect, locate and classify different types of faults in a series compensated EHV/UHV transmissionline.
Alhamdulillah, finally my project report entitled “Quality Function Deployment As Optimum Design Solution for TransmissionLine Project” is complete. Millions of gratitude to my Master Project Supervisor, Associate Professor Dr. Mohamad Ibrahim Mohamad for his patient, advice and assistance throughout the process of the project period..
The center frequencies of the two bands are 0.95 GHz and 2.2 GHz. When these two frequencies are used to design a dual-band Wilkinson power divider on a common substrate, the parameters of the power divider are calculated by using (2)–(5). The input impedance of each transformer section can be obtained as Z 1 = 98 . 34 Ω, Z 2 = 50 . 84 Ω and Z 3 = 54 . 38 Ω, and the length is calculated as θ 1 = θ 2 = θ 3 = 54 . 29 ◦ .
one of the important parts of the market rules . Successful competition at the generation level calls for a successful, fair and non-discriminatory open access for the transacting entities in the market. Evaluation of transmission services plays an important role to determine whether contribute transmission open access and allied services is economically favorable to both the wheeling usage and customers of transaction . Few years back, electricity transmission pricing was more of an academic interest, rather than practical use . This is because generation, transmission and distribution were vertically desegregated. The vertically integrated usages used to sell their power inside their region. Hence, the need for having a formal mechanism for pricing of transmission did not exist . The costs incurred by the vertically integrated utilities were recovered by embedding them in the electricity price billed to the consumers. However, in recent times, as a primary step towards reforms, generation and transmission businesses have been separated from each other in many countries transmission costs are used to charge the transaction of power flow . Engineering analysis determining the feasibility of supply and the cost of transmission services providing is only one of the many considerations in the overall process of pricing transmission services Apart from cost recovery, can the pricing provide any other information? Based on this, some principles of transmission pricing have been developed, which are discussed next .