JP2711897B2 - Power supply for traveling wave tube - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling wave tube power supply, and more particularly to a traveling wave tube power supply having a current measuring function at a floating potential point.

[Conventional technology]

A traveling wave tube used in a microwave band amplifier needs to supply a high voltage with respect to a cathode to each electrode, that is, a collector, an anode, and a helix, in addition to heating a filament. These three types of high-voltage power supplies must be independently set and stabilized.
In this case, the helix is grounded and the cathode has a floating potential, and the collector is also applied with a voltage with the cathode as a reference point. In order to protect the traveling wave tube and control its output, it must also have a function of measuring the current of each electrode. To control the microwave band output of a traveling wave tube, it is necessary to measure the collector current. However, since the collector is at the floating potential point of the high voltage as described above, the current measuring means must also be performed in a state of floating charging to the high voltage. Further, when a tube having a plurality of collector electrodes is used in order to improve the amplification factor of the traveling wave tube, it is necessary to measure the currents of the plurality of collectors in a state of floating charging to a high voltage. Therefore, a power supply device for a traveling wave tube has a large number of inverters, a rectifier, and a current measuring function provided with insulating means, and when combined with these insulating means, it becomes a huge component.

[Problems to be solved by the invention]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a traveling wave tube power supply device that has a simple and economical insulation configuration while independently controlling the power output to each electrode and having a current measurement function.

[Means for solving the problem]

SUMMARY OF THE INVENTION In order to solve such problems, the present invention relates to a traveling wave tube for supplying power in a state in which the helix is grounded and the cathode is floatingly charged, the traveling wave tube having a cathode, a first collector, a second collector, an anode and a helix. A power supply device, wherein a first rectifier circuit, a second rectifier circuit, and a third rectifier circuit of a bridge type are driven via an insulating transformer supplied from a single AC power supply, and the first rectifier is driven by a first rectifier. One of the output terminals of the circuit is connected to the cathode, the other is connected to the second collector, one of the output terminals of the second rectifier circuit is connected to the cathode, the other is connected to the first collector, and the output terminal of the third rectifier circuit is connected to the first collector. One of the output terminals is connected to the cathode, the other is connected to the anode and the helix via a power control circuit, and two sets of primary windings are connected to one of the AC input side lines of the first rectifier circuit. To the first container It proposes a traveling-wave tube power supply apparatus characterized by measuring the inductor current and the current of the sum of the second collector current. The present invention also proposes a means for selecting the diode of the first rectifier circuit so that one arm has twice the current capacity.

〔Example〕

FIG. 1 shows an embodiment of the present invention. Inverter 1 generates a high-frequency alternating current of about 50 kHz, and applies a high-frequency high voltage to secondary winding 202 of transformer 2 via transformer 2. This 2
One end of the secondary winding 202 is first connected via a primary winding 501 of the current transformer 5 to a bridge-type rectifier circuit 6 including diodes 601 to 605.
The other end of the secondary winding 202 is connected to one input terminal 608 of the bridge-type rectifier circuit 6 via the other primary winding 502 of the current transformer 5. You. The negative output terminal 609 of the bridge type rectifier circuit 6 is the cathode terminal 10
And the positive output terminal 607 is connected to the second collector terminal 11. A reset resistor 504 is connected in parallel with the secondary winding 503 of the current transformer 5. Further, it is connected to a smoothing capacitor 506 and terminals 507 and 508 via a diode 505.

The secondary winding 202 of the transformer 2 is also connected to input terminals 305 and 306 of the voltage doubler rectifier circuit 3. The voltage doubler rectifier circuit 3 includes diodes 301 and 303 and capacitors 302 and 304. The negative output terminal 308 of the voltage doubler rectifier circuit 3 is connected to the cathode terminal 10, and the positive output terminal 307 is connected to the first collector terminal 1
Connected to 2.

Further, the secondary winding 202 of the transformer 2 is also connected to the input terminals 409, 410 of the quadruple voltage rectifier circuit 4. The quadruple voltage rectifier circuit 4 includes diodes 401, 403, 406, 407 and capacitors 402, 404, 405, 4
08 and the negative output terminal of the 4x rectifier circuit 4.
411 is connected to the cathode terminal 10, and the positive output terminal 412 is connected to the ground via the power control circuit 8. The power control circuit 8 is configured by connecting six field effect transistors 801 to 806 in series, and controls the potential between the cathode terminal 10 and the helix terminal 14.

A series circuit of the power control circuit 7 and the resistor 712 is connected between the cathode terminal 10 and the power control circuit 8, and an anode terminal 13 is connected to an interconnection point between these. The power control circuit 7 includes ten field effect transistors 701 to 710, and the field effect transistor 710 is insulated and driven by the optical coupling element 711.

The power supply device configured as described above has the inverter 1
Four kinds of DC high voltage outputs can be obtained with one high-frequency source from the cathode terminal 10 as a reference. First, a voltage of 2 kV is generated between the cathode terminal 10 and the second collector terminal 11. Then, a voltage of 4 kV, which is twice the first collector voltage, is generated at the first collector terminal 12 with reference to the cathode terminal 10. Further, a DC high voltage of about 7 kV is applied between the cathode terminal 10 and the helix terminal 14 which is grounded. Therefore, the potential of the cathode terminal 10 is floatingly charged to -7 kV. A part of the potential of the cathode terminal 10 is divided and controlled by the power control circuit 7 and the resistor 712, and is supplied to the anode terminal 13. Here, when each current is expressed as follows, the cathode current Ik is expressed by the following equation.

Anode current: Ia Cathode current: Ik Helix current: Ih First collector current: Ic1 Second collector current: Ic2 Ik = Ic1 + Ic2 + Ia + Ih where the anode current Ia and the helix current Ih are the first collector current Ic1 and the second collector current Since these values are so small that they can be ignored compared to Ic2, if these values are ignored, the equation is approximated as follows.

Ik ≒ Ic1 + Ic2 ... The current I501 of the primary winding 501 of the current transformer 5 when the diode 505 conducts is I501 = 1/2 · Ic2 ... The primary current of the current transformer 5 when the diode 505 conducts. The current I502 of the winding 502 is I502 = 1/2 · Ic2 + Ic1. Therefore, if the turn ratio of each winding is 1, the current I505 flowing in the diode 505 is I505 = I501 + I502 = Ic1 + Ic2 ≒ Ik. Is approximately equal to the cathode current Ik. This is smoothed by the capacitor 506, and a signal substantially equal to the cathode current Ik is generated at the terminals 507 and 508.

The diodes 604 and 605 of the bridge rectifier circuit 6 are connected in parallel with each other and have twice the current capacity of the other arms. The current of the voltage doubler rectifier circuit 3 joins this arm, and the current of the other arm flows twice as much as that of the other arm.

〔The invention's effect〕

Since the present invention has the above-described features, it is possible to measure the current of a plurality of collectors of a traveling-wave tube while floatingly charged to a high voltage, and to measure the current while isolating the DC current. Works with a single container. The AC current transformer has a simpler configuration than the DC current transformer, and is suitable when floating charging is performed at a high voltage. Further, since a single transformer is used to insulate while supplying an alternating current for driving a rectifier circuit floatingly charged to a high voltage, the number of insulation points is minimized, and reliability and safety are further improved. Furthermore, by combining the two floatingly charged rectifier circuits as in the present invention, the capacity of the diode of the high voltage rectifier circuit can be economically selected.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a traveling wave tube power supply device according to the present invention. DESCRIPTION OF SYMBOLS 1 ... Inverter 2 ... Transformer 3 ... Voltage doubler rectifier circuit 4 ... Quadruple voltage rectifier circuit 5 ... Current transformer 6 ... Bridge type rectifier circuit 7 ... Power control circuit 8 ... Power control circuit 10 ... Cathode terminal 11 ... 2nd collector Terminal 12: First collector terminal 13: Anode terminal 14: Helix terminal

Claims (2)

(57) [Claims] 1. A traveling wave tube power supply device for supplying power to a traveling wave tube having a cathode, a first collector, a second collector, an anode, and a helix while grounding the helix and floatingly charging the cathode. Driving a first rectifier circuit, a second rectifier circuit, and a third rectifier circuit of a bridge type through an isolation transformer supplied with power from a single AC power supply; One is connected to the cathode and the other is connected to the second collector,
One of the output terminals of the rectifier circuit is connected to the cathode, the other is connected to the first collector, one of the output terminals of the third rectifier circuit is connected to the cathode, and the other is connected to the anode and the power supply circuit via a power control circuit. Connected to a helix, and two sets of primary windings are connected to a single current transformer on both of the lines on the AC input side of the first rectifier circuit so that the first collector current and the second
A power supply device for a traveling-wave tube, which measures a sum of collector currents. 2. The traveling-wave tube power supply device according to claim 1, wherein a diode of said first rectifier circuit is selected to have twice the current capacity of one arm.