Low-carbon development (or low-carbon economy) is
gradually becoming a global trend, which is widely regarded as the only way for
human development in the future. After the "Copenhagen Conference",
the Chinese government has issued a series of "low-carbon"
environmental protection policy measures, which was jokingly called "China’s
low-carbon first year" in 2010. With the change of policy and consumption
environment, "Green UPS" and "Green UPS technology" have
become the strategic heights of the leading UPS market, lead-free production,
DSP technology, IGBT rectifier technology, APFC technology and so on have been
greatly developed and applied, which is very obvious in the HP9330 series UPS
model of Solder Company.
The real green "low-carbon" UPS
power supply is characterized by small harmonic current, small harmonic
pollution to power grid, high efficiency of UPS operation and reduction of
The ideal UPS should show pure resistance
to the power grid, that is to say, the best power factor of UPS is 1, so it has
no pollution to the power grid. But the reality is that most UPS generally use
50Hz low-frequency thyristor rectifier, which produces a lot of harmonic
feedback pollution to the power grid. The problem facing all users is to
control harmonic pollution, just like we control chemical plants. Like sewage
discharge, harmonics cause great harm.
The main harmonic hazards are as follows:
1. Make the motor produce additional loss,
heat, pulsating torque and noise. The utility model can heat the coil of the
power transformer, accelerate the aging of the insulation, shorten the service
life, and cause additional loss and noise.
2. It interferes with circuit breaker,
leakage protector, relay and other protection and automatic control devices,
resulting in misoperation.
3. Shorten the service life of lighting
4. The measurement error of ammeter,
voltmeter, power meter and electric energy meter is caused.
5. Generate electrostatic interference and
electromagnetic interference to adjacent communication lines.
6. Cause series / parallel resonance of
electrostatic compensation capacitor of distribution system.
7. Increase the power distribution line
loss, heat generation, shorten the insulation life, and even cause short
circuit and fire.
8. Due to harmonics, the sudden change of
voltage will cause damage to electronic equipment and malfunction, which will
affect the normal operation of computer programs. It will cause data loss, even
damage hardware, cause building automation, fire alarm system, security system
malfunction, or even unable to work.
At present, the main ways to control the
harmonic pollution of ups in the market are: 6 pulse rectifier + input filter;
12 pulse rectifier; 12 pulse rectifier + input filter; active filter. All these
ways have a common disadvantage, that is, pollution first and then control.
Because the structure of SCR rectifier is adopted by UPS, it will inevitably
cause harmonic pollution, and then users are forced to spend more. If UPS
doesn't produce or rarely produces harmonic pollution, users don't need to
spend money on it.