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公开(公告)号：SE339043B
公开(公告)日：1971-09-27
申请号：SE1157668
申请日：1968-08-28
Applicant: DANFOSS AS
Inventor： JENSEN A , PETERSEN T
Abstract: 1,250,195. D.C. to A.C. static inverters. DANFOSS A.S. 13 Aug., 1968 [29 Aug., 1967], No. 38615/68. Heading H2F. In a D.C./A.C. inverter, it is arranged that commutating capacitors C1, C2, Fig. 3, are always charged up before their associated load rectifiers ES2, ES4 are fired. Thyristors ES1, ES3 are first fired sequentially to charge up the commutating capacitors C1, C2, via R2 and R1 respectively, in preparation for subsequently effecting the turn-off of load current thyristors ES2, ES4. Thyristor ES2 is then fired and passes load current via a blocking diode E2 and choke L3 to an output point W. At the same time the charge on C1 is reversed by current flowing through ES2, diode El and a choke L1, and in addition ES1 is blocked. C2 also receives a supplementary charge, which will offset any leakage, by current flowing from L3 by way of diode E5 so long as thyristor ES3 remains conducting. ES1 is then fired whereby C1 discharges to turn off ES2. Thus a positive half wave of square waveform has been passed to the output phase terminal from the centre tap of L3. Immediately thereafter the load thyristor ES4 is fired and it passes, via diode E5, a negative half wave to the output terminal, a sequence as for ES2 being repeated. If the load is inductive, current continues to flow in the same direction after the conducting load thyristor is blocked. This current will flow through freewheel diodes E6 and E8 or E3, E 7 as the case may be, until it is reversed when the other load thyristor conducts. The firing pulse circuit as shown in Fig. 1, produces square waveforms b, b 1 in antiphase, from a null detector 1, which are differentiated at 4, 9 and fed to impulse transformers 10, 13 to produce firing pulses i 1 , i 2 for the quenching thyristors ES1, ES3. In addition, delayed pulses Z 1 , Z 2 to fire the load thyristors ES2, ES4 are derived from b, b 1 by first passing b, b 1 through delay circuits 5, 8 before differentiating at 6, 9.
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公开(公告)号：SE305024B
公开(公告)日：1968-10-14
申请号：SE1640665
申请日：1965-12-17
Applicant: DANFOSS AS
Inventor： JENSEN A
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.
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公开(公告)号：DK145650B
公开(公告)日：1983-01-10
申请号：DK60973
申请日：1973-02-06
Applicant: DANFOSS AS
Inventor： JENSEN A
Abstract: A three-phase inverter for producing a stepped voltage approximating to a sinusoidal form, and largely free of odd harmonics, wherein, for the purpose of producing each phase voltage a basic and two additional rectangular impulses are summed, the basic impulse being shortened in relation to a half-wave and occupying substantially the entire amplitude-time area of the phase voltage, and the additional impulses having a considerably smaller amplitude and shorter duration than the basic impulse. One of the additional impulses procedes and the other is superimposed on a basic impulse of the same polarity.
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公开(公告)号：DK140774C
公开(公告)日：1980-04-14
申请号：DK24869
申请日：1969-01-17
Applicant: DANFOSS AS
Inventor： PETERSEN T K , JENSEN A
IPC: H02K20060101 , H02M5/45 , H02P20060101 , H02P27/06 , H02P7/62 , H02P13/18
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公开(公告)号：DK135920C
公开(公告)日：1978-01-23
申请号：DK25169
申请日：1969-01-17
Applicant: DANFOSS AS
Inventor： JENSEN A
IPC: H02P7/62
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Patent Agency Ranking
公开(公告)号：DK541176A
公开(公告)日：1977-06-04
申请号：DK541176
申请日：1976-12-02
Applicant: DANFOSS AS
Inventor： JENSEN A
Abstract: The invention relates to a control unit for an inverted rectifier of the type having a constant DC voltage supply and a frequency settable by a frequency control signal. The main feature of the control unit relative to the invention hereof is the monitoring of the critical pulse spacings of the pulse generator output without the use of time-dependent elements. The control unit includes a voltage controlled oscillator for generating a triangular wave form controlled by a frequency control voltage. A variable width pulse generator is fed by the triangular wave form and is controlled by a pulse width control voltage. The control unit includes an analog computer for generating internally thereof a function which corresponds to the spacing of the pulses of the pulse generator. The computer includes an amplifier having a noninverting input for receiving a control signal which corresponds to the amplitude of the triangular wave form. The inverting input of the amplifier receives a combined signal corresponding to the frequency control voltage and the pulse width control voltage. The output of the computer is a digital signal which occurs when a critical predetermined value of the computer generated function is reached.
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公开(公告)号：NO135044C
公开(公告)日：1977-01-26
申请号：NO199072
申请日：1972-06-05
Applicant: DANFOSS AS
Inventor： JENSEN A
IPC: G01R17/02
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公开(公告)号：NO135044B
公开(公告)日：1976-10-18
申请号：NO199072
申请日：1972-06-05
Applicant: DANFOSS AS
Inventor： JENSEN A
IPC: G01R17/02
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公开(公告)号：DK131067B
公开(公告)日：1975-05-20
申请号：DK413168
申请日：1968-08-28
Applicant: DANFOSS AS
Inventor： JENSEN A
Abstract: 1,175,029. Control of A.C. motors. DANFOSS A.S. 20 Aug., 1968 [29 Aug., 1967], No. 39715/68. Heading H2J. [Also in Division H3] A three-phase oscillator has three identical units, each producing a trapezoidal waveform (a, Fig. 4, not shown), having three straight sections (12, 13, 14) per half-wave, each section being of 60 electrical degrees duration. The units are connected in a ring (Fig. 1, not shown) successive outputs (T, S, R) being shifted 240 degrees backwards (Fig. 2, not shown). Each unit (Fig. 5, not shown) consists of a square-wave generator (4) in which complementary transistors (Trl, Tr2) are either both on or both off, and change state when the input trapezoidal waveform (a) passes through zero, to produce a square wave (b). The magnitude of (b) is varied by applying variable D.C. bias levels (+B, -B) to diodes (E2, E3); and the resulting square wave (c) is integrated in an integrator (6) which includes two seriesopposed Zener diodes across the integrating capacitor to limit the amplitude (13) of the resulting sawtooth. For a given limit amplitude, and with the 60-degree duration for each part of the waveform, which is required to maintain oscillation. in the ring, variation of the slope of the trapezoidal waveform varies its frequency. The slope is varied by changing the square-wave amplitude by adjusting the bias levels (+B, -B). In an asynchronous motor control circuit, Fig. 6, the motor 15 is driven by positive and negative supply voltages 16, 17 supplied alternately by switches 19, 20 which are operated alternately by the trapezoidal output of one unit 22 of the above generator. The frequency of the output R is varied in dependence on the value of the supply voltages 16, 17, controlled at 18, by means of potentiometers 23, 24 and 25, 26. Alternatively (Fig. 7, not shown), an external D.C. signal (B) varies the frequency and the supply voltages (27, 28) are varied by the unit (22). These circuits provide a given relationship between frequency and amplitude of the motor drive voltages to maintain constant torque with speed variation.
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公开(公告)号：CA934817A
公开(公告)日：1973-10-02
申请号：CA44849
申请日：1969-03-06
Applicant: DANFOSS AS
Inventor： JENSEN A
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