Real-time control-type dynamic voltage regulator (DVR)

Fast and real-time correction of voltage sag/swell to ensure voltage stabilityVoltage sag problem solution

With the rapid growth of modern power industry and the significant changes in the electrical load structure in the system, the dependence of social production and officing on electronic equipment is growing rapidly, in which voltage sag becomes a major problem. According to EPRI's authoritative data, more than 92% of power quality events are related to voltage sag and swell, and other power quality events account for less than 8%. Voltage sag has been identified by many international research institutions as the most-frequently occurred event in the power system. Therefore, voltage sag (swell) protection for sensitive equipment is particularly important.

Comprehensive control benefits of voltage sag

  • Ensure that the load terminal voltage is good and the loss caused by the voltage sag event can be reduced.
  • Prevent the loss of equipment failure and avoid waste of raw materials and damage to equipment by controlling the voltage sag and swell.
  • Avoid equipment from consumption of inferior power, reduce factory maintenance costs, and ensure product quality.
  • Avoid accidents caused by data and control system disorder due to voltage sag.
  • Save the cost of maintenance and battery replacement for users, and eliminate the disposal of used batteries and avoid environmental pollution.
  • No harmonic injection into the grid, no additional filtering equipment investment required for traditional UPS

Application industry

KLD-DVR dynamic voltage regulator has been widely used for precision equipment protection in industry occasions e.g. industrial, mining, semiconductor, hospital, finance, subway, rail transit, infrastructure, commercial centers, oil and gas exploration, telecommunications, airport or port and large logistics facilities, as well as data centers.

Applications case

Case on precise equipment protection of a hospital

Load profile

Sophisticated medical equipment in hospitals, such as CT machines, X-ray machines, MRI nuclear magnetic resonance, etc., have high requirements on power quality. Lack of power factor, harmonic interference, and sudden voltage changes may result in severe consequences.

Treatment Measures

The treatment measures are to install a KLD-DVR dynamic voltage regulator for the MRI NMR front end.

Dynamic voltage regulator treatment effect

The front part is the grid supply voltage waveform, and the rear waveform is the output waveform after KLD-DVR compensation. As clearly seen from the comparison of treatment effect, the voltage waveform is almost sinusoidal after inputting KLD-DVR, and the voltage value is basically stable at about 220V. The power quality is brought under thorough control. After installing KLD-DVR, the MRI NMR operation becomes normal. When the power grid suddenly loses power, the output voltage is quickly switched to inverter output. The output is free of power loss, and the switching time is 0ms to enable seamless switching. The switching moment is as shown in the figure below.