Title :
High power harmonic-free AC to DC rectification
Author :
Limpaecher, R. ; Rodriguez, R. ; Bush, M. ; Vinacco, K. ; Gatewood, M.
Author_Institution :
DC Transformation Inc., Beverly, MA, USA
Abstract :
The Sequential Discharge Rectification (SDR) system is a regulated high power AC to DC converter, producing a DC output with no VAr and harmonics generation. The technology is based on the property of resonance circuits, thereby permitting the use of soft switching and self commutating low dI/dt solid states devices. The switching characteristics permit the utilization of less expensive thyristors available in high voltage, high current and high power ratings. The new circuit topology allows the energy extraction from any phase to be proportional to the square of the instantaneous line voltage. The energy extraction, performed at constant intervals, will load the AC line to the desired power level over the entire AC cycle. Since the load which the SDR technique imposes on the multiple phase inputs is equivalent to a resistive load, it produces no VAr and harmonic distortions that must be filtered out. The rectification approach of this invention includes about the same number of components as a conventional bridge rectification approach. The low dI/dt permits the utilization of high voltage high power thyristors for megawatt power applications. Test data are presented for a 144 kW AC to DC demonstration system producing a dual low ripple DC output of ±260 VDC. The output can be regulated, its fault current protected, with a turn-on and turnoff of about 2-3 msec and complies with the harmonic requirements imposed by the IEEE 519-1992 and IEC 555-2 specifications
Keywords :
AC-DC power convertors; commutation; rectifying circuits; resonant power convertors; switching circuits; thyristor convertors; 144 kW; 2 to 3 ms; 260 V; AC to DC converter; IEC 555-2; IEEE 519-1992; SDR technique; Sequential Discharge Rectification system; circuit topology; dual low ripple DC output; energy extraction; harmonic-free AC to DC rectification; high current; high power; high power ratings; high voltage; instantaneous line voltage; multiple phase inputs; rectification approach; resistive load; resonance circuits; self commutating low dI/dt solid states devices; soft switching; switching characteristics; thyristors; DC-DC power converters; Frequency conversion; Power harmonic filters; RLC circuits; Reactive power; Resonance; Solid state circuits; Switching circuits; Thyristors; Voltage;
Conference_Titel :
Power Modulator Symposium, 1996., Twenty-Second International
Conference_Location :
Boca Raton, FL
Print_ISBN :
0-7803-3076-5
DOI :
10.1109/MODSYM.1996.564489