Disadvantages And Disadvantages Of Hvc And DVC Power Transmission Line

The impact of the proposed sequences has been simulated for 0.4 modulation index with a 0.5 lagging power factor load (power factor angle 60°). The simulation setup consists of the following software: 1) MATLAB/Simulink – used to implement the modulation strategies and switching sequences, and 2) PSIM – used to simulate the T-NPC inverter running with an R-L load and to provide conduction and switching losses of each switch. The inverter switching pulses were generated within Simulink and were fed to PSIM through sim-coupler module which provides a link between PSIM and simulink for the purpose of co-simulation [29].

The electric field generated by the HVDC transmission line is a mixture of electrostatic field created by the line voltage and the field of space charge because the charge generated by corona line. Study of environmental influence of the electric field around the HVDC transmission line is occur in Canada and Russia have shown that discomfort to people who usually felt under the HVAC transmission line is not observed under HVDC line. This discomfort ascends from the release of the human spark to shrubs, grasses, and other plants. Although emissions also happen under the influence of an electric field of HVDC transmission line, the disposal is quite rare in contrast to emissions caused by rise HVAC transmission lines, which may amount to 100 departures per second. Subjective, the sensations felt by humans standing under HVDC overhead lines usually do not go beyond electrostatic stimulation of hair on the head of the movement. Such results suggest that the electrostatic field under HVDC transmission lines is limited and generally not harmful to humans. A study in Canada found

Multilevel inverters have ability to generate low switching frequency high quality output waveforms with several high voltages and higher power applications and the general structure of multilevel converter is synthesizes a sinusoidal voltage from several level of voltages. The multilevel inverter has overcome the limitations of conventional two level voltage converters. The advantages of multilevel inverter are higher power quality, lower switching losses, low electromagnetic interference and higher voltage capability.

IN RENEWABLE dc-supply systems, batteries area unit usually required to back-up power for electronic equipment. Their voltage levels are generally abundant under the dc-bus voltage. Bidirectional converters for charging/discharging the batteries area unit thus needed. For high-powered applications, bridge-type bidirectional converters have become a very important analysis topic over the past decade. For raising power level, a dual full-bridge configuration is sometimes adopted

This report aims to discuss the working of DC-AC converter for photovoltaic systems and how it has been implemented to convert renewable energy into usable power to be supplied to the load (power supply application).A topology of a two-stage DC-AC converter has been designed in which a boost converter and a full bridge inverter act as an interface between the photovoltaic (PV) array and the power supply applications. A controlled strategy called Maximum Power Point Tracking (MPPT) technique has been used for achieving maximum power output at the load. Various modes of operation of the converter and the inverter are also discussed. MATLAB Simulink environment has been used for designing the circuitry and to observe various waveforms related to the output.

The most frequently used voltages and wiring in the primary distribution system are listed in Table 1. Primary distribution, in low load density areas, is a radial system. This is economical but yields low reliability. In large cities, where the load density is very high, a primary cable network is used. The distribution substations are interconnected by the feeders (lines or cables). Circuit breakers (CBs) are installed at both ends of the feeder for short-circuit protection. The loads are connected directly to the feeders through fuses. The connection is similar to the one-line diagram of the high-voltage network shown in Fig. 1. The high cost of the network limits its application. A more economical and fairly reliable arrangement is the loop connection, when the main feeder is supplied from two independent distribution substations. These stations share the load. The problem with this connection is the circulating current that occurs when the two supply station voltages are different. The loop arrangement

In this paper a zero voltage switched active network (Fig. 1) used in combination with three-phase ac to dc diode rectifiers is presented. It is shown that by using proposed switching network in three-phase ac to dc boost converter, zero switching losses are obtained while maintaining a unity input power factor. Active network capacitor, Cs, diodes D7, and D8, maintain a zero voltage during turn-off of Q1, and Q2, Capacitor, Cs, discharges through the boost inductors of the circuit thus limiting the rate of rise of current during turn-on. Moreover, the advantage of the proposed active network is that it can maintain a zero voltage switching over the entire range of the duty cycle of the operation. Consequently, boost stage can be used directly to control the dc bus voltage by varying the duty cycle at Constant switching frequency. The resulting advantages include higher switching frequencies, and better efficiency. Finally the operation of the active switching network is verified experimentally on a prototype three-phase ac to dc converter.

relationships.This new seven-level inverter is configured using a capacitor selection circuit and a full-bridge power converter, connected in cascade. The capacitor selection circuit converts the two output voltage sources of dc–dc power converter into a three-level dc voltage, and the full-bridge power converter further converts this three-level dc voltage into a seven-level ac voltage. In this way, the proposed solar power generation system generates a sinusoidal output current that is in phase with the utility voltage and is fed into the utility. The salient features of the proposed seven-level inverter are that only six power electronic switches are used, and only one power electronic switch is switched at high frequency at any time. A prototype is developed and tested to verify the performance of this proposed solar power generation system.

AC electrical energy in grid interactive PV system. To achieve direct medium-voltage which is present at grid without using bulky medium-voltage transformer ,cascaded multilevel converters are attracting more and

ABSTRACT: Power flow control in a long transmission line plays a vital role in electrical power system. This paper uses the shunt connected STATCOM for the control of voltage and power flow. The proposed device is used in different locations such as sending end, middle and receiving end of the transmission line. The PWM control is used to generate the firing pulses of the controller circuit. Simulation modeling of the system is carried out using MATLAB/SIMULINK. Based on a voltage-source converter, the STATCOM regulates system voltage by absorbing or generating reactive power. This paper deals with a cascaded multilevel converter model, which is a 48-pulse (three levels) GTO converter. The simulation studies are carried for sending end, middle and receiving end of the transmission line. The objective is to define the reactive power generated and voltage control at different locations (at sending end, middle, receiving end) of transmission line using STATCOM. KEYWORDS: FACTS device, STATCOM, SVC, PWM, MATLAB /Simulink.

Mokhtar Ali et al. [41] gave new technique which allows the use of lower voltage Rated Semiconductor .This improves the performance of the system. This technique use SEPIC as the practical driver. L.K. Wong et al. [42] gave that Conventional method like averaging and small signal linearization are enough and powerful for basic converts like buck and boost but for high order like SEPIC these are not sufficient so the Meson’s gain formula and signal flow graph help the manipulation. Mohammad Mahdavi et al. [43] introduced a new PFC converter that have reduced no of component that subsequently reduces conduction losses. This proposed converter is operating in discontinuous conduction mode and having only voltage control loop i.e. no current loop is required whereas conventional arrangement have Booth loop controls and also operates in continuous conduction Mode. M.S. Song et al. [44] gave that by providing a direct new way between input and output by using some Auxiliary diodes and switches in addition to the SEPIC converter provided a highly efficient step up and step down converter in continuous mode. Ashish Shrivastava et al. [45] gave PFC based LED driver for power factor correction in the ac system. This topology consists PFC SEPIC converter which is operating to drive LED lamp in the continuous conduction mode. In this

In the present era of advanced technologies, power electronics devices have wide applications. These devices are important for industrial and domestic uses but they generate the power quality problems [1-2].these problems are created on account of these devices

This project has been carried out at the department of the electrical engineering at S.V.I.T. Vasad. It has been great opportunity to work with this project and get knowledge about this area of the power electronics.

Fast charging is becoming the leading technology used to reenergize electric vehicles in 30 – 60 minutes. With the ownership of EVs doubling each year, the need to implement efficient, fast charging infrastructure is progressively increasing. There are two technical approaches to establish fast charging 1. via a high power, 3-phase AC connection from an AC charging post at the charging station to an on-board high power charger in the EV or 2. via a high power DC connection from a high power DC charger at the charging station directly to the terminals of the battery in the EV. In this section, we will review AC level 2, DC/AC level 3 charging stations to improve our knowledge and the design of our project.

Abstract— this paper presents a brief overview of standards for power electronics. All the standards presented in this paper are currently active and are approved by the Institute of Electrical and Electronics Engineer Standards Association (IEEE-SA) and American National Standards Institute (ANSI).