With the rapid development of the society, electrical equipment is increasing day by day.
However, the end-user voltage is too low due to aging and development of power transmission and distribution facilities, as well as poor design and insufficient power supply, while the end-user voltage is often too high, which is unique as an unfixed time bomb for electric equipment, especially for high and new technology and precision equipment with strict voltage requirements.
Grid system as public power grid, the tens of thousands of all kinds of loads connected to the above, some of the larger sensibility, capacitive, such as switching power supply load not only won the electricity from the grid, and will in turn affect the power grid itself, deterioration or local networks of power supply quality, cause the mains voltage waveform distortion or frequency drift.
In addition, accidental natural and man-made accidents, such as earthquake, lightning strike, power transmission and transformation system circuit or short circuit, will endanger the normal supply of electricity, thus affecting the normal work of the load.
Unstable voltage will cause fatal injury or wrong operation of equipment, affect production, cause delivery delay, quality instability and other losses.
At the same time, the aging of equipment will be accelerated, the service life will be affected and even the accessories will be burned out, which will make the owners face the trouble of needing maintenance or need to update the equipment in a short time, thus wasting resources.
In serious cases, safety accidents even occur, causing incalculable losses.
According to the tests of power experts, the problems that often occur in the power grid and cause interference or damage to computers and precision instruments mainly include the following:
___________ surge (power surges) : refers to the output voltage RMS values higher than the 110% rating, and duration of one or several cycles.
Power surges are mainly caused by the sudden unloading of the grid of high voltage when large electrical equipment connected to it shuts down.
2. High voltage spike: voltage reaching a peak of 6,000 v and lasting from a millionth of a second to a half cycle (10ms).
This is mainly due to lightning strikes, arc discharges, static discharges, or switching operations of large electrical equipment.
Transient overvoltage: Pulse voltage up to 20000V but with a duration limit of one millionth to one thousandth of a second.
The main cause and possible damage is similar to the high pressure spike pulse, but the solution is different.
Voltage sag: A low voltage state where the effective value of the municipal voltage is between 80 and 85 percent of the rated value and lasts for one to several cycles.
Large equipment starting, large motor starting, or large power transformer access can cause this problem.
Electrical line noise: Means radio frequency interference (RFI) and electromagnetic interference (EFI) as well as various other high-frequency noise.
The operation of motors, the operation of relays, the operation of motor controllers, broadcast emission, microwave radiation, and electrical storms can all cause line-noise interference.
Pictures of frequency deviation: means a change of the commercial frequency beyond 3Hz or more.
This is mainly due to the unstable operation of emergency generators, or by frequency unstable power supply.
Therefore, the use of voltage regulator is essential for the use of electrical equipment, especially for the high and new technology and precision equipment with strict voltage requirements.