公开(公告)号：DK135920B

公开(公告)日：1977-07-11

申请号：DK25169

申请日：1969-01-17

Applicant: DANFOSS AS

Inventor： JENSEN A

IPC: H02P7/62

公开(公告)号：DK541076A

公开(公告)日：1977-06-04

申请号：DK541076

申请日：1976-12-02

Applicant: DANFOSS AS

Inventor： JENSEN A

IPC: H02M7/527 ,  H02P

Abstract: The invention relates to a method and apparatus for controlling an inverted rectifier having a constant DC supply voltage and adjustable frequency and amplitude of the fundamental oscillation of the output voltage. The rectifier is for an AC motor and the phase voltage is at least partly formed by width-modulated pulses and the voltage-time area of the pulse series is increased to eliminate an inadequate pulse spacing. Switching elements in the rectifier require a certain switching time and care must thus be taken to ensure that certain minimum pulse widths or pulse spacings must be observed to avoid short circuiting in the rectifier. Also to be avoided is pulse bridging which leads to a sudden increase in the voltage-time area and thus to a leap in the amplitude of the fundamental oscillation of the output voltage. The effects of this, e.g. in the magnetization of a connected motor, are undesirable. In accordance with the invention the increase in the voltage-time area is partially compensated by a reduction in the widths of at least some of the remaining pulses. Every time the voltage-time area is suddenly increased, the width of other impulses is reduced by way of compensation. The entire voltage-time area is therefore not suddenly increased, so that a substantially continuous voltage control can be achieved. If the remaining pulses have a smaller width after the compensation, the spacing therebetween is increased and the following switching-over becomes delayed. In a preferred embodiment each phase voltage consists of six sections of which the third and fourth are unmodulated, the second and fifth are occupied by wider impulses, and the first and sixth are occupied by narrower impulses, and switching-over to unmodulated operation takes place in the second and fifth or first and sixth sections and the reduction in impulse widths takes place in the respective remaining sections. This form of phase voltage gives a linked voltage that has extremely few higher harmonics. This switching-over produces between the normal operation and the maximum voltage, at which the entire half-wave consists of a through-going voltage block, at least one intermediate stage in which regulation is possible without the impulse spacings becoming too small.

公开(公告)号：SE360957C

公开(公告)日：1975-11-20

申请号：SE84769

申请日：1969-01-22

Applicant: DANFOSS AS

Inventor： JENSEN A

IPC: H02P27/04 ,  H02P27/06

公开(公告)号：DK130099C

公开(公告)日：1975-06-02

申请号：DK104869

申请日：1969-02-26

Applicant: DANFOSS AS

Inventor： JENSEN A

IPC: H02P27/06 ,  H02P7/00 ,  H02P27/08 ,  H02P13/20

公开(公告)号：SE333761B

公开(公告)日：1971-03-29

申请号：SE656165

申请日：1965-05-19

Applicant: DANFOSS AS

Inventor： JENSEN A

IPC: C21C5/28 ,  C21C5/38 ,  F23N5/08 ,  H03K17/72 ,  H01H47/22

Abstract: 1,075,317. Thyristor switching circuits. DANFOSS A.S. May 13, 1965 [May 22, 1964], No. 20249/65. Heading H3T. [Also in Divisions Cl and G4] An A.C. switching circuit comprises an element 11 rendered conductive by ultra-violet radiation, temperature or pressure and fed from an A.C. source U-O by a voltage multiplier 7, 8. When the voltage across A-O is sufficient, element 11 conducts to discharge capacitor 8 through the element 11 and fire a device 9 which remains conducting until the voltage across it falls to a predetermined level. The current through device 9 energizes relay 4. In a modification, Fig. 2 (not shown), the cathode of device 9 is connected to the anode of the rectifier 7 and the relay 4 and capacitor 5 are connected in parallel in one of the leads 3, thereby reducing the number of conductors in cable 6 to two. The switching circuit may be used in a burner control system.

公开(公告)号：DK111529B

公开(公告)日：1968-09-09

申请号：DK632865

申请日：1965-12-09

Applicant: DANFOSS AS

Inventor： JENSEN A

IPC: H01C7/04 ,  H01L45/00 ,  H03K17/70

Abstract: 1,065,930. Semi-conductor devices. DANFOSS A.S. Dec. 16, 1965 [Dec. 22, 1964], No. 53473/65. Heading H1K. A switching device comprises a semi-conductor element 1 having a negative temperature coefficient of electrical resistance and a pair of electrodes 2, 3 in contact with opposite faces of the semi-conductor element 1, the thickness of the semi-conductor element being reduced in a selected region (e.g. by means of a recess 6) so that when a voltage is applied between the electrodes a channel 8 of high electrical conductivity is formed in the selected region.

公开(公告)号：SE302992B

公开(公告)日：1968-08-12

申请号：SE1625866

申请日：1966-11-28

Applicant: DANFOSS AS

Inventor： JENSEN A

IPC: H01H37/52 ,  H01H61/02 ,  H01H61/00 ,  H01H61/013 ,  H01H61/04

Abstract: 1,130,660. Control of A.C. motors. DANFOSS A.S. 16 Nov., 1966 [7 Dec., 1965], No. 51292/66. Heading H2J. [Also in Division H1] In a thermal bi-metal switch having contacts 4, 5, Fig. 1, mounted on the bi-metal through which the current to be cut off is passed to heat the bi-metal and open the contacts 4, 5, the contacts are maintained open by the passage of current through a resistive film 8 on an adhesive insulating strip 9 attached to the bi-metal and electrically connected across the open contacts. The switch may be adjusted by a screw (not shown) engaging one of the bimetallic elements. The film 8 may be of colloidal graphite mixed with epoxy resin and is electrically connected to the bi-metal at points 13, 14 of colloidal silver mixed with the epoxy resin. The conductivity of the insulating strip 9 may be increased at the intermediate connecting region 12 by a short-circuiting metal layer. A further insulating or reflecting layer may be attached to the film 8 to reduce heat losses. The switch may be used in series with an auxiliary winding for starting a single-phase asynchronous A.C. motor.

公开(公告)号：GB1075317A

公开(公告)日：1967-07-12

申请号：GB2024965

申请日：1965-05-13

Applicant: DANFOSS AS

Inventor： JENSEN A

IPC: C21C5/28 ,  C21C5/38 ,  F23N5/08 ,  H03K17/72

Abstract: 1,075,317. Thyristor switching circuits. DANFOSS A.S. May 13, 1965 [May 22, 1964], No. 20249/65. Heading H3T. [Also in Divisions Cl and G4] An A.C. switching circuit comprises an element 11 rendered conductive by ultra-violet radiation, temperature or pressure and fed from an A.C. source U-O by a voltage multiplier 7, 8. When the voltage across A-O is sufficient, element 11 conducts to discharge capacitor 8 through the element 11 and fire a device 9 which remains conducting until the voltage across it falls to a predetermined level. The current through device 9 energizes relay 4. In a modification, Fig. 2 (not shown), the cathode of device 9 is connected to the anode of the rectifier 7 and the relay 4 and capacitor 5 are connected in parallel in one of the leads 3, thereby reducing the number of conductors in cable 6 to two. The switching circuit may be used in a burner control system.

公开(公告)号：NL6506205A

公开(公告)日：1965-11-23

申请号：NL6506205

申请日：1965-05-14

Applicant: DANFOSS AS

Inventor： JENSEN A

IPC: C21C5/28 ,  C21C5/38 ,  F23N5/08 ,  H03K17/72

Abstract: 1,075,317. Thyristor switching circuits. DANFOSS A.S. May 13, 1965 [May 22, 1964], No. 20249/65. Heading H3T. [Also in Divisions Cl and G4] An A.C. switching circuit comprises an element 11 rendered conductive by ultra-violet radiation, temperature or pressure and fed from an A.C. source U-O by a voltage multiplier 7, 8. When the voltage across A-O is sufficient, element 11 conducts to discharge capacitor 8 through the element 11 and fire a device 9 which remains conducting until the voltage across it falls to a predetermined level. The current through device 9 energizes relay 4. In a modification, Fig. 2 (not shown), the cathode of device 9 is connected to the anode of the rectifier 7 and the relay 4 and capacitor 5 are connected in parallel in one of the leads 3, thereby reducing the number of conductors in cable 6 to two. The switching circuit may be used in a burner control system.