Through five core mechanisms, namely, double conversion architecture, power frequency isolation, harmonic suppression, wide-range voltage stabilization and zero switching, power frequency on-line UPS realizes deep purification of power in complex industrial power grids and provides nearly ideal pure sine wave power supply for loads.
First, the double transformation online architecture: isolating pollution from the source
This is the core guarantee of power purity. The load is powered by inverter 100% of the time and completely decoupled from the mains.
Commercial power mode: commercial power → rectifier (AC→DC)→ DC bus → inverter (DC→AC)→ load. All interferences (harmonics, surges and noises) of the commercial power are completely blocked in the rectification link, and the inverter outputs a brand-new pure sine wave without interference.
Battery mode: When the commercial power is interrupted/abnormal, the battery directly supplies power to the DC bus, the inverter continuously outputs, and the switching is seamless for 0ms, so the load is not perceived, and the continuity and purity of power supply are not affected.
Core value: completely isolate all interference on the power grid side, with extremely high output voltage/frequency accuracy (voltage stabilization 1% ~ 3%, frequency stabilization 0.1%) and waveform distortion rate (THD)<2%.
Second, the power frequency isolation transformer: electrical isolation+deep immunity.
Built-in power frequency isolation transformer is the key to distinguish power frequency machine from high frequency machine, which provides triple purification ability:
Electrical total isolation: cut off the electrical connection between the commercial power and the load, and block the ground potential circulation, common-mode interference and lightning surge conduction path.
Zero-ground voltage control: effectively suppress the zero-ground voltage (which can be reduced to < 1V), and solve the equipment misoperation and data error caused by zero-ground drift in industrial field.
Harmonic and spike suppression: filter out high-frequency noise, voltage spike and pulse interference, improve the purity of output waveform, and enhance the load impact resistance.
Third, harmonic control: reduce power grid pollution and improve input quality.
Harmonic (mainly 3rd, 5th and 7th order) of industrial power grid is the main pollution source, and power frequency UPS is suppressed by multistage technology:
12-pulse rectifier: phase-shifting transformer+double 6-pulse rectifier bridge, input current THD<10% (traditional 6-pulse > 30%), greatly reducing the harmonic feedback to the power grid.
Active filter (APF): Medium and high power models have built-in APF, which can dynamically compensate 3rd to 50th harmonics, increase the power factor to above 0.95, and reduce power grid pollution and electricity fines.
Input EMI/RFI filtering: the front-end multi-stage EMI filter filters out high-frequency conduction and radiation interference, which conforms to industrial electromagnetic compatibility standards.
4. Wide-range voltage stabilization and dynamic regulation: adapting to the fluctuation of industrial power grid.
The voltage of industrial power grid fluctuates violently (20% ~ 30%), and the power frequency UPS ensures the pure output through wide input and accurate voltage stabilization;
Ultra-wide input range: the three-phase model supports 280 V ~ 475 V (25%) and the single-phase model supports 165V~275V, so it can adapt to the harsh power grid without additional voltage regulator.
Fast dynamic response: fully digital DSP control, voltage regulation response < 20ms, dealing with instantaneous shocks such as motor start-up and sudden load change, and the output voltage has no obvious fluctuation.
Frequency synchronization and phase locking: automatically track the mains frequency (45~65Hz), switch to the internal crystal oscillator reference when it is abnormal, and the output frequency is absolutely stable.
V. Bypass and protection mechanism: Balance purity and reliability.
Static bypass+isolation: When UPS fails/overloads, the static switch < 4ms cuts the bypass, and the bypass is output through the isolation transformer, which still retains the anti-interference ability.
Multi-level protection: Built-in surge absorption (TVSS), over-voltage/under-voltage, over-current, short-circuit, overheating protection, blocking abnormal energy impact and protecting the load and UPS itself.
Intelligent battery management: automatic switching between floating charge and even charge, temperature compensation, to ensure that the battery can provide stable DC energy at any time and ensure the purity of inverter output.
