Title :
Power calibrator using switched mode voltage source
Author :
Zajec, Peter ; Nastran, Janez
Author_Institution :
Fac. of Electr. Eng., Lyubljana, Slovenia
fDate :
8/1/2000 12:00:00 AM
Abstract :
The paper is focused on a sophisticated switched mode power supply with a pure sinusoidal output voltage waveform with frequency (40-65 Hz) and voltage range (30-500 V). In order to cope with stringent voltage (10.2%) and distortion constraint (THD<0.7%) in a modern calibration system, traditional inverter design with an output LC filter is upgraded with a feedback-feedforward control principle. The paper presents the voltage source topology, analyzes its steady-state response and gives its comprehensive evaluation. Using a simple sensor that is capable to detect a small voltage asymmetry at the presence of a high AC component (500 VRMS), the parasitic DC component is limited below 5 mV. Experimental results demonstrate exceptional voltage accuracy (<0.2%) and low total harmonic distortion (THD)
Keywords :
active networks; calibration; circuit feedback; feedforward; harmonic distortion; invertors; power meters; reference circuits; switched mode power supplies; voltage control; watthour meters; 30 to 500 V; 40 to 65 Hz; LC filter; PI controller; SMPS; active voltage wave shaping; bridge invertor; current control loop; distortion constraint; feedback-feedforward control principle; low total harmonic distortion; parasitic DC component; phase correction; power calibrator; reference circuit; sample and hold circuit; single phase calibrator; sinusoidal output voltage waveform; small voltage asymmetry; steady-state response; switched mode voltage source; voltage accuracy; voltage constraint; voltage control loop; voltage source topology; Calibration; Control systems; Filters; Frequency; Inverters; Steady-state; Switched-mode power supply; Topology; Total harmonic distortion; Voltage control;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
