It introduces a series of models, such as an analysis of interaction between the power grid and the communication network, differential protection in smart distribution systems, data flow for VLAN-based communication. This book provides a comprehensive introduction to different elements of smart city infrastructure - smart energy, smart water, smart health, and smart transportation - and how they work independently and together.
Theoretical development and practical applications are presented, along with related standards, recommended practices, and professional guidelines. Throughout the book,. The goal of this conference is. The latest edition features a new chapter on implementation and operation of an integrated smart grid with updates to multiple chapters throughout the text.
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This book consists of the identification, characterization, and modeling of electromagnetic interferences in substations for the deployment of wireless sensor networks. The authors present in chapter 3 the measurement setup to record sequences of impulsive noise samples in the ISM band of interest. The setup can measure substation impulsive noise, in. The 12 full papers presented together with 3 short papers were carefully reviewed and selected from 32 submissions.
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The chapters are organized into five parts: Architecture and Design, Energy Switching and. Home Iec Based Smart Substations. Gas-puffer breaker interruptor — from the stationary assembly, the SF6 gas in the closed.
Compressing Main contacts the gas increases its dielectric strength. Eventually, separate Gas the moving contact assembly moves so far that the comnpressing arcing contact fingers separate, and an arc forms in chamber Figure When the arcing fingers separate, the compres- sion chamber opens, and thehigh-pressure gas Arcing contacts still meet flows through the arc to the low pressure areas of the interruptor.
The dielectric strength of the high-pressure gas weakens the arc. As the gas flows Figure Gas-puffer breaker interruptor — through the arc, the arc is lengthened and cooled, main contacts open. Arc Figure Gas-puffer breaker interruptor - arcing contacts open. Figure is an illustration of typical time-travel traces. The time-travel test is typically performed for several types of breaker operations.
Transducer and timing rod on an oil circuit breaker. Contact Resistance Test Resistance in the closed contacts of a circuit breaker can have a number of causes, including arcing deposits, a loose or incomplete connection, or pitting from repetitive arcing.
Contact resistance creates heat that can reduce the life of the contacts and possibly even lead to breaker failure. The purpose of contact resistance testing is to detect unacceptably high contact resistance levels Figure Time-travel traces. In principle, the test is performed by passing a direct current through the closed contacts of the breaker and measuring the voltage drop across the contacts Figure The test instrument uses the current and voltage values to calculate and display the contact resistance.
If the contact resistance exceeds an acceptable limit, the contacts may have to be cleaned or replaced. Performing a contact resistance test. The purpose of insulation resistance testing is to detect unacceptably low levels of insulation resis- tance before poor or weakened insulation results in failure.
Performing an insulation resistance Then, leakage current is measured either to test. The capacitor banks offset the excessive demand for inductive power, and thus bring the power factor closer to unity.
Excessive demand for non-working capacitive power also results in a lower power factor than desirable. In this case, instead of increasing power output to meet the demand for capacitive power, the utility can improve the power factor by using shunt reactors. The shunt reactors offset the excessive demand for capacitive power.
Figure Figure Clearing Capacitor Banks The main steps for safely clearing a capacitor bank for maintenance are similar to the steps taken to clear any other device in a substation. These steps include de-energizing, isolating, testing for dead, and grounding. However, a capacitor bank is different from other devices in a substation in that it stores an electrical charge even after the bank has been separated from its source of energy.
Because of this ability to store a charge, some special safety Figure De-Energizing and Isolating a Capacitor Bank A capacitor bank is de-energized by electrically Capacitor separating the bank from its source of energy. In this example, the capacitor bank is de-energized by opening the circuit breaker. A capacitor bank is isolated by physically separating the bank from its source of energy. As Circuit breaker illustrated in Figure , the capacitor bank in this example is isolated by opening the three single- Figure Substation capacitor bank.
Opening these switches provides a visible break between the source of energy and the capacitor bank. The actual switching devices that are operated and the sequence in which they are operated vary with the design of the substation. This is done by opening the regulator source and load disconnect Source Load disconnect switches.
The disconnect switch that is opened switch disconnect switch first depends on the design of the system and on company procedures. The specific procedure for switching a regulator out of service may vary.
For example, the type of switch shown in Figures and enables Figure Regulator bypass switch closed. The switch in this example is made up of two bars. When the switch is closed, Source Load one bar connects the source circuit to the source circuit circuit lead of the regulator. The other bar connects the Bars load lead of the regulator to the load circuit. The separated by insulators two bars are separated by insulators. By opening the switch, three switching operations are completed in one action.
The first operation Regulator Regulator is bypassing the regulator. When the switch is source lead load lead opened, a spring operated plate Figure moves into the space where the switch was. The Figure Disconnect switch. Load circuit contact For the second operation, the regulator is isolated from the source circuit. When the switch is opened, there is a visible separation between the source circuit and the regulator source lead. For the third operation, the regulator is isolated Plate Source circuit from the load circuit.
When the switch is opened, contact there is a visible separation between the regulator load lead and the load circuit. Disconnect switch opened. Physically Disconnecting the Regulator Generally, single-phase regulators in a substation are grouped in three-phase banks, as shown in Figure To remove one of the regulators, all three units must be taken out of service. After the regulators have been switched out of service, they are tagged, tested for dead, and grounded according to company procedures.
To remove the regulator, its conductors are discon- nected from the regulator terminals. In Figure , one of the conductors has been marked Figure Three single-phase regulators.
For example, a distance relay in substation A can be set for a voltage-to-current ratio that would cause the relay to operate for a fault anywhere on the section of line between substations A and B.
With this setting, however, the relay might trip for a fault near substation B but between substations B and Figure Fault between substations B and C. C Figure This type of relay operation is undesirable, because the basic approach to trans- mission line protection is to isolate only the section of line in which a fault occurs. For a fault between substations B and C, a relay in substation B should open a breaker in substation B, and, possibly by transfer tripping, also open a breaker in substation C to isolate the fault.
If a distance relay in substation A operates, it would isolate the section of line between substations A and B, even though that section of line does not have to be isolated to remove the fault from the system. Zoned Protection To prevent undesirable operations, a distance relay Figure Zone 1 protection.
This protected section is typically sections referred to as Zone 1 Figure To protect line sections between substations, additional Zone 1 sections can be set up Figure Multiple Zone 1 protection. A common way to provide complete protection for line sections is to use a distance relay in each substation that provides Zone 1 protection in the opposite direction Figure This arrange- ment provides overlapping protection for each line section between substations.
Overlapping Zone 1 protection. For example, as illustrated in Figure , Zone 2 protection from substation A covers the line section between substations A and B, as well as part of the line section between substations B and C. Zone 3 protection from substation A covers the line sections between substations A and B, substa- tions B and C, and part of the line section beyond substation C. Zone 2 and Zone 3 protection from substation A.
For example, potential transformers Figure change, or transform, line voltage to a proportionally lower voltage for measurement. Another example of sensing equipment is a current transformer. Current transformers Figure transform line current to a proportionally lower current for measurement.
Current transformer. Measuring Equipment The signals from sensing equipment are typically sent to measuring equipment and control- ling equipment. Measuring equipment measures the signal provided by sensing equipment and indicates the value of the condition being sensed.
For example, a meter such as the ammeter shown in Figure indicates the value of current it receives from a current transformer. Another example of measuring equipment is a recording meter, such as the one shown in Figure A recording meter measures signals from sensing equipment and records the values of the signals over a period of time. Recording meter. Controlling Equipment Controlling equipment detects the signals it gets from sensing equipment, and, if a signal is different from a preset value, provides a signal that operates various other equipment.
An example of controlling equipment is an overcurrent relay, such as the one shown in Figure An over current relay detects current that it receives from a current transformer.
It will continue to supply the loads until alternating current is restored or until the battery is fully discharged. Cell Components and Electrochemical Action Substation battery maintenance and testing are more likely to be performed properly when the worker knows the construction of the battery cells, how the cells work, and what can go wrong with the cells and why. This section describes the components and electrochemical action of a typical lead-acid substation battery cell.
Components of a Lead-Acid Cell Battery cells used in substations are typically lead-acid cells. The external components of a typical lead-acid cell Figure include a container, which is often called a jar, positive and negative terminal posts, and a vent with a flame arrestor.
The flame arrestor shields explosive gases at the vent from external sparks or flames. The internal components include a liquid called an electrolyte, conductive lead-based plates, and non-conductive separators. The electrolyte is composed of sulfuric acid and water. Components of a lead-acid cell. Figure shows a cell that has been disas- sembled so that the plates and separators can be seen. The plates are arranged so that the negative plates and the positive plates alternate.
A cell always has one more negative plate than positive, and the plates at each end of the cell are negative. This is because each positive plate needs a negative plate on each side of it in order to function efficiently.
All the positive plates are mechanically and electri- cally linked together by a bus bar and connected to one of the terminal posts. The negative plates are Figure Disassembled lead-acid cell. The non-conductive separa- tors insulate the negative and positive plates from each other. The most widely used cell plate design is a type called the pasted plate, although there is a variety of other designs. The pasted plate uses porous lead compounds for the chemically active portions of the plate.
Plate grid and lead. To begin the cell replacement procedure, the jumpers are connected to cells 6 and 8 and to the new cell Figure One end of a jumper is connected to the negative terminal of cell 6, Bad cell and the other end of the jumper is connected to the positive terminal of the new cell. One end of a second jumper is connected to the positive Figure Typical cell arrangement - one bad terminal of cell 8, and the other end of that jumper cell.
The jumpers are connected to the terminal so Positive that they will not interfere with the removal and Negative reinstallation of the intercell connecting straps.
With the jumpers in place, the bad cell is then disconnected from the battery by removing the intercell connecting straps between cells 6 and 7 and between cells 7 and 8. Because the new cell is connected in parallel, no arcing occurs when the New cell intercell connecting straps are disconnected from the bad cell.
Jumper connections to bypass bad cell. Next, the bad cell is removed from the battery rack, and the new cell is put in its place Figure Once the new cell is in place, it is connected to the adjacent cells in the battery. The intercell connecting straps are reinstalled, connecting the negative terminal of cell 6 to the positive terminal of the new cell, and the positive terminal of cell 8 to the negative terminal of the new cell.
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