Solid insulating materials can be classified into two main categories: organic and inorganic. There are a large number of solid inorganic insulants available, including the following: • ALUMINA: produced by heating aluminum hydroxide or oxyhydroxide; it is widely used as a filler for ceramic insulators. Further heating yields the corundum
Year: 2015
The effective resistance offered by a conductor to high frequencies is considerably greater than the ohmic resistance measured with direct currents (dc). This is because of an action known as the skin effect, which causes the currents to be concentrated in certain parts of the conductor and leaves the remainder
A typical modern power system is a high-order multivariable process whose dynamic response is influenced by a wide array of devices with different characteristics and response rates. Stability is a condition of equilibrium between opposing forces. Depending on the network topology, system operating condition and the form of disturbance, different
“Power system stability is the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance, with most system variables bounded so that practically the entire system remains intact”. The definition applies to an interconnected
The term alternative energy is referred to the energy produced in an environmentally friendly way (different from conventional means, i.e., through fossil-fuel power plants, nuclear power plants and hydropower plants). Alternative energy considered in this dissertation is either renewable or with high energy conversion efficiency. There is a broad range
The five major factors that contribute to the renewed interest in distributed generation (DG) system: Electricity market liberalization Developments in DG technologies Increased customer demand for highly reliable electricity. Environmental concerns. Constraints on the construction of new transmission lines. ADVANTAGES OF DISTRIBUTED GENERATION SYSTEMS: UTILITY PERSPECTIVE: On-site power supply avoids
Distributed Generation (DG) also called as site generation, dispersed generation, embedded generation, decentralized generation, decentralized energy or distributed energy, generates electricity from the many small energy sources. In recent years, micro electric power systems such as photovoltaic generation systems, wind generators and micro gas turbines, etc., have increased with the
Main features of power MOSFETs are: a) MOS type FETs are basically majority carrier devices; consequently, they differ greatly from bipolar transistors which are minority carrier devices. b) MOS type FETs are not current controlled devices as are bipolar transistors. They are voltage controlled devices and are controlled by the
The circuit, shown below, uses a UJT to trigger a SCR. The UJT is used to more accurately trigger the SCR. When the source voltage exceeds 20V, the zener diode (DZ) will begin to conduct, applying a DC voltage across the base connections of the UJT. At the same time,
GTO being a monolithic p-n-p-n structure just like a thryistor its basic operating principle can be explained in a manner similar to that of a thyristor. In particular, the p-n-p-n structure of a GTO can be though of consisting of one p-n-p and one n-p-n transistor connected in the regenerative
