Patents Assigned to Kraftelektronik AB
  • Patent number: 6373723
    Abstract: The method of invention relates to a method and device for generating voltage peaks in an electrostatic precipitator via generation of current pulse, where each voltage peak is generated by a group of current pulses. A device according to the invention comprises a first and a second means for converting alternating current to direct current, and also so first means for converting direct current to alternating current, and the first means for converting direct current to alternating current comprises a resonance converter.
    Type: Grant
    Filed: December 11, 2000
    Date of Patent: April 16, 2002
    Assignee: Kraftelektronik AB
    Inventors: Bernt Wallgren, Andreas Wramdemark
  • Patent number: 4713093
    Abstract: An electrostatic dust precipitator comprises a separation filter (5) having emitter and collector electrodes (4,6), means (1-3) for maintaining a substantially constant d.c. voltage between the electrodes (4,6) during operation of the precipitator, and pulse-generating means (1-3, 7-11) for generating at a given frequency in the order of 30-500 Hz voltage pulses or voltage pulse trains which are superimposed on the d.c. voltage and which are of short duration in relation to the aforesaid frequency. The pulse-generating means (1-3, 7-11) includes capacitive and inductive elements (7,8) which together with the capacitance of the separation filter (5) form an electrical oscillation circuit, and a switching device (9) which is incorporated in said circuit and which is periodically actuatable by a control means (11) for activation of the oscillation circuit (5,7,8). The pulse-generating means (1-3, 7-11) further includes a known voltage-controlled frequency converter (1) which is arranged to generate an a.c.
    Type: Grant
    Filed: July 8, 1986
    Date of Patent: December 15, 1987
    Assignee: Kraftelektronik AB
    Inventor: Curt Hansson
  • Patent number: 4600877
    Abstract: In a transformer having a primary winding which is connectable to an a.c. voltage source via switch means which opens and closes at a controllable frequency, there is connected in parallel with the primary or secondary winding of the transformer a circuit which for at least a part of the time during which the switch means opens maintains magnetization of the transformer in a direction opposite to the direction of the magnetization caused by the subsequent closing of the switch means.
    Type: Grant
    Filed: September 19, 1984
    Date of Patent: July 15, 1986
    Assignee: Kraftelektronik AB
    Inventor: Rolf Soderholm