Safety distance and safety value of electromagnetic radiation of transformer
Writer： Hengfeng you electric Time：2023-04-14 views：times
According to the maintenance requirements of relevant distribution equipment, the maintenance scope of a 115kv distribution station transmission line is 10m outside the line. In other words, if the transmission line is 10m, the safety of electromagnetic induction radiation can be ensured. The total maintenance area of 225kv and 500kV substation engineering system software transmission lines is 15m and 20m respectively.
The electromagnetic energy frequency of power lines and machinery and equipment is 50Hz. The specific harm to the periphery is mainly caused by the extremely low frequency magnetic field with small kinetic energy and poor radiation characteristics according to the magnetic effect of current. The harm to the surrounding electromagnetic induction natural environment is ignored, let alone no harm to the body.
According to the international EMC specification, the frequency above 9000hz is called wireless communication frequency. In other words, a switching power supply with a frequency less than 9000hz can be considered as basically not transmitting radio waves due to the small amount of radiation. The 50 Hz DC is 180 times smaller than 9000hz, and its radiation power is small and does not harm people. Does the transformer radiate much to the pregnant mother.
On the basis of specific and accurate measurement, even for kv500 UHV transmission line, the radiation compressive strength is lower than 53db, and the radiation output power of the total area of the enterprise is equal to one thousandth of the compression strength of the radio wave radiation output power received by ordinary large city residents, which is naturally not easy to cause all harm to personal safety. Therefore, its radiation compressive strength is not as strong as that of household desktop computers and mobile phones. It can be basically ignored. It pays less attention to computers and mobile phones, so as to prevent less and less radiation.
Safety distance and safety value of electromagnetic radiation of transformer
1. Actual operating frequency
The core loss of transformer is closely related to the frequency, so it should be designed, manufactured and applied according to the application frequency. This kind of frequency is called the working frequency.
2. Maximum power
Under the required frequency and working voltage, the transformer can work for a long time without exceeding the required heating power.
3. Rated current
It refers to the working voltage allowed to be released on the transformer solenoid, and the standard value shall not be exceeded during operation.
4. Operating voltage ratio
It refers to the ratio of primary working voltage to secondary working voltage of transformer, and whether there is a difference between load working voltage ratio and load working voltage ratio. Does the high voltage transformer have radiation.
5. No load current high voltage tower transformer radiation.
There is still a certain current in the secondary lead of the transformer, which is called no-load current. No load current consists of magnetized current (caused by magnetic flux) and iron loss current (caused by transformer frame loss). For the hz50 output power transformer, the no-load current basis is equivalent to the magnetized current.
6. No load loss
It refers to the accurate measurement of output power loss during the secondary lead of transformer. The key loss is the loss of transformer core, followed by the loss caused by no-load current on the copper resistor of primary solenoid coil (copper loss), which is very small. Is there radiation in the distribution station.
7. High efficiency
It refers to the percentage of the ratio of secondary output power P2 to primary output power P1. Generally, the greater the maximum power of the transformer, the higher the efficiency. Is there a transformer in the room radiating.
8. Is there radiation in the 35kV transformer with grounding resistance.
It shows the dielectric strength energy between the electromagnetic coil of the transformer and between the electromagnetic coil and the iron core of the transformer. The height of grounding resistance is related to the characteristics, temperature and environmental humidity of common insulating layer materials.
