Protective actions for the correctness and accuracy of energy measurement increasingly demanding

With the continuous development of EHV power system and electricity market mechanisms to expand the introduction of protective actions for the correctness and accuracy of energy measurement increasingly high demand, and thus the transformer accurate performance also made more Voltage stabilizer . Meanwhile, the scientific and technological development and the actual project needs, there are many new transformer specifications and products. To accommodate this situation, China Electric Power Planning and Design Association organize the preparation of the "current transformers and voltage Electric transformer and Calculation Guide." Performance on the transformer selection and parameter calculations made ​​provisions to regulate power engineering design work. This article will focus on the application of protective current transformer problem as a rough introduction. Protective current transformer air circuit breaker selection principle characteristics and type of protection not only in the normal operation of the current transformer requires a certain accuracy, and more importantly, in the case of short-circuit fault in a circuit which can power transformer spread changes to the secondary circuit, and the error does not exceed the specified value, in order to ensure correct operation of protective devices.

Electromagnetic radiation is still in people's awareness and research stage

Electromagnetic radiation is nearly four decades was only a new awareness of environmental pollution, electromagnetic radiation is now still in the stage of awareness and research. Due to its invisible, intangible, difficult to detect, it is easy to arouse people's concerns. In addition, some reports on electric transformer radiation is not an objective, lack of science, leading to unnecessary misunderstandings and panic. Generally speaking, it is determined whether the living environment of electromagnetic Voltage stabilizer, electromagnetic radiation intensity should be the main radiation direction, with the radiation source distance, duration and other aspects to consider. Therefore, electromagnetic protection while enhancing the electromagnetic power transformers should also be taken to a scientific attitude, objective analysis seriously, must not others, and is not responsible for the blind exaggerated, causing confusion in people's understanding. Of course, with the level of development of science and technology, electromagnetic pollution and endanger people's awareness will gradually deep, many answers will eventually be lifted.

Radio and television are using electromagnetic waves to carry

Radio and television are using electromagnetic waves to carry. In radio, the people have the sound signals into electrical signals, and the signals from the high frequency oscillation wave propagation with the air circuit breaker space. In another location, people use the receiver receives these electromagnetic waves, which in turn signals back into sound signal, which is the general process of radio. In the TV, in power transformers as the radio signal as in sound processing, but also the image of the light signals into electrical signals, and these are joined together by two signals with high frequency oscillation wave propagation to the surrounding space, the television receiver Voltage stabilizer signals will be one of the electromagnetic wave and then back into sound signals and optical signals to display a screen of a television and voice from the loudspeaker.

Not have any impact of electromagnetic radiation on the human body

In fact, not just any electromagnetic radiation on the human body has an impact, as long as the intensity is not, there is air circuit breaker to the human body. As for the market to sell the products anti-electromagnetic radiation, mostly without any effect, we should not be deceived. Remember, electromagnetic shielding method only with circuit breakers or metal plate, or on the use of thick concrete or soil to absorb. If you can not shield strength of strong Circuit breaker waves, so you will not be affected only way to stay away from the radiation source, because of the intensity of electromagnetic waves and is inversely proportional to the square of the distance, that is twice the distance of the original, the intensity is reduced to the original quarter.

Reduce the adverse effects of electromagnetic waves, it is necessary to develop self-protection

Reduce the adverse effects of electromagnetic waves, we must cultivate the habit of self-protection. General Electric Co has sold "electromagnetic test pen", you can easily measure the intensity of mcb circuit breaker waves, as long as more than the standard warning is issued, the user should be kept away until the warning disappears analyte. To detect electrical circuit breakers radiation or electric transformer waves, you can also take a more convenient way is to use home and small can receive AM (amplitude modulation) radio channels open after no broadcast channels tune in place, and to be close to the measured TV, refrigerator, microwave oven and other appliances or computer, if you find the radio noise that came abruptly, indicating that the appliance is surrounded by a strong electromagnetic radiation. After going some distance, the noise will restore the original small amount of noise;

No electromagnetic wave propagation medium, with the frequency of electromagnetic waves in different media at different speeds

Transverse electromagnetic waves. Electromagnetic field, the electric field and perpendicular to the traveling direction of the three. Amplitude in the vertical direction along the propagation direction for the alternating cycle, the intensity is inversely proportional to the square of the distance, the wave energy to drive itself, the energy power anywhere proportional to the square of the amplitude. Is equal to the speed of light c (3 × 10 ^ 8m / s). In the space propagation of electric meter waves, the nearest electric (magnetic field) strength in the same direction, the magnitude of the maximum distance between two points, that is, the wavelength of the electromagnetic wave λ, the number of changes per second is the electromagnetic frequency f. The relationship between the formula by c = λf. No electromagnetic wave propagation medium, with the frequency of electromagnetic waves in different media at different speeds. Different frequencies of Circuit breaker waves, propagate in the same medium, the higher the frequency the greater the refractive index, the smaller the speed. And the electromagnetic wave only in a homogeneous medium to the same along a straight line, if the same kind of medium is uneven, the electromagnetic wave in which the refractive index is not the same, in such a medium is transmitted along the curve. Air circuit breaker media occurs when the refraction, reflection, diffraction, scattering, and absorption, etc. Propagation of electromagnetic waves propagate along the surface of the ground wave propagation in the air as well as from the air waves and sky. The longer the wavelength the less the attenuation, the longer the wavelength of electromagnetic waves are also more likely to continue to spread around obstacles. Mechanical waves and electromagnetic waves can happen refraction, reflection, diffraction, interference, because all the waves have volatility. Diffraction, refraction, reflection, interference belong volatility.

Electromagnetic wave frequency is low, mainly through the conductor will be delivered tangible

Electromagnetic wave frequency is low, mainly borrowed from the conductor to transfer tangible. The reason is that the low frequency circuit breakers, the magnetic interaction between the change is slow, almost all of the energy return of the original circuit without the energy radiated out; air circuit breaker high frequency which can be transmitted in free space, can also be bound in tangible conducting in vivo delivery. In free space mcb circuit breaker because the high frequency oscillations, the magnetic interaction becomes very fast, not all return to their original energy of the oscillator circuit, so electric, magnetic as the periodic variation of electric and magnetic fields in the form of electromagnetic waves into space spread out, no medium can pass out energy, which is a kind of radiation. For example, the distance between the Sun and the Earth is very far away, but when outdoors, we can still feel the warm sun light and heat, which is like a "phenomenon of electromagnetic radiation by the radiation energy transfer," the same principle.