Table of Contents
- 1 What should be the insulation level of the transformer?
- 2 What is the purpose of basic insulation level?
- 3 How is a transformer liquid insulating level determined?
- 4 What is insulation coordination?
- 5 What is insulation coordination explain?
- 6 What is insulation in construction?
- 7 What determines the insulation level of a series transformer?
- 8 What are the factors affecting the cost of a transformer?
What should be the insulation level of the transformer?
The impulse level of lines and equipment must be high enough for the arresters to provide protection but low enough to be economically practical….Basic insulation level, kV. (standard 1.5- × 40-μs wave)
| Basic insulation level, kV (standard 1.5- × 40-μs wave) | ||
|---|---|---|
| 5.0 | 60 | 75 |
| 8.7 | 75 | 95 |
| 15 | 95 | 110 |
| 23 | 110 | 150 |
What is the purpose of basic insulation level?
Definition: A design voltage level for electrical apparatus that refers to a short duration (1.2 x 50 microsecond) crest voltage and is used to measure the ability of an insulation system to withstand high surge voltage.
What are the factors affecting insulation coordination?
The requirement of insulations is determined by considering the following factors.
- Highest Power Frequency System Voltage.
- Temporary Power Frequency Overvoltages.
- Transient Overvoltage Surge.
- Withstand Levels of the equipment.
- 2 thoughts on “Insulation Co-ordination”
What are the insulating materials used in power transformer?
The solid insulation materials widely used in the transformer are paper, press- board, and transformer board, which are formed from the cellulose found in plants. Cellulose insulation with mineral oil has played a major role as the main insulation system for transformers for a very long time.
How is a transformer liquid insulating level determined?
The ‘insulation level’ of such designs is determined by a combination of the specified clearances and the ability to withstand, for one minute, the prescribed value of test voltage. This is accepted as equivalent to the power frequency and impulse voltage test philosophy.
What is insulation coordination?
Insulation coordination is the process of selecting the most cost-effective equipment dielectric strength and its application to avoid equipment insulation damage or affect continuity of service.
What is basic impulse level BIL?
Definition: A reference impulse (voltage) insulation strength expressed in terms of the peak value of the withstand voltage of a standard impulse voltage wave. It is used to express the ability of electrical equipment such as transformers to withstand certain levels.
What is insulation coordination of an apparatus?
What is insulation coordination explain?
Insulation co-ordination is the technique used to ensure that the electrical strengths of the various items of plant making up the transmission and distribution system and their associated protective devices are correlated to match the system characteristics and expected range of voltages.
What is insulation in construction?
Essentially, insulation is any material used to fill the spaces (including little gaps, crevices and hard-to-reach places behind walls, above ceilings, etc.) of your home to reduce heat flow by reflection and/or absorption.
Why insulation resistance test is taken in electrical installation?
An insulation resistance (IR) test measures the total resistance between any two points separated by electrical insulation. The test, therefore, determines how effective the dielectric (insulation) is in resisting the flow of electrical current.
What is insulation coordination and how it is achieved among substation equipments?
What determines the insulation level of a series transformer?
LI Peng, in Unified Power Flow Controller Technology and Application, 2017 The insulation level between the series transformer grid-side winding and the ground is not related to rated voltage, but rather to terminal insulation level. The insulation level is determined by the AC system.
What are the factors affecting the cost of a transformer?
The amount of insulation provided on any piece of apparatus and particularly the transformers constitutes quite an appreciable part of the cost. The standardizing bodies have had in mind to fix the basic insulation level or BIL as low as is commensurate with safety.
What is the Basic Insulation Level?
The minimum level is known as the Basic Insulation Level (BIL) that must be that of all of the components of a system. Figure 1a – Insulation coordination. Insulation values above this level for the lines and equipment in the system must be so coordinated that specific protective devices operate satisfactorily below that minimum level.
What is the effect of voltage on insulation insulation?
Insulation levels recommended for a number of voltage classes are listed in Table 1. As the operating voltages become higher, the effect of a surge voltage becomes less; hence, the ratio of the BIL to the voltage class decreases as the latter increases.