JP3171420B2 - Power supply for traveling wave tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device for a traveling wave tube,
In particular, the present invention relates to a traveling wave tube power supply device with reduced ripple.

[0002]

2. Description of the Related Art A traveling-wave tube used in an amplifier in a microwave band not only heats a filament but also needs to supply a high voltage with respect to a cathode to each electrode, that is, a collector, an anode, and a helix. These three types of high voltage power supplies must be independently set and stabilized in voltage.

In general, the helix electrode of a traveling-wave tube is grounded for the purpose of adjustment and protection, so that a high voltage for the helix is reflected and applied to the cathode. Therefore, the potential of the cathode is -5 kV to -10 kV with respect to the ground point.
The collector power, anode power, and filament power, which are floatingly charged at the high potential, are driven by a high frequency inverter via an insulating transformer.

In the power supply device for a traveling-wave tube configured as described above, since the high-frequency high-voltage circuit is floatingly charged, the floating high-frequency component flows to the ground through the floating capacitance and then loads. Return to the cathode potential of the power supply through the traveling wave tube. That is, the high frequency component is applied as an output ripple between the helix and the cathode of the traveling wave tube. Ripple of the power supply causes spurious emission of the traveling wave tube and is not preferable. Therefore, it is necessary to reduce the ripple.

In order to reduce the output ripple, there is a method of increasing the capacitance of a filter capacitor between output terminals. However, the capacitance of the capacitor unnecessarily supplies an instantaneous current to a traveling wave tube. It is not preferable because it works to increase the size and shortens the life of the tube. In addition, the volume of the high-voltage capacitor and the volume of its insulator are bulky and uneconomical.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to reduce inductive output ripple in a traveling wave tube power supply without increasing the capacitance of an output circuit.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a transformer driven by a high-frequency inverter, a first rectifier circuit connected to a secondary winding of the transformer. A cathode terminal and a collector terminal of a traveling wave tube connected to an output terminal of the first rectifier circuit, and a second rectifier circuit connected to a secondary winding of a transformer. One end of the output terminal of the circuit is connected to the cathode terminal of the traveling-wave tube, and the other end of the output terminal is connected to the helix of the traveling-wave tube.
The present invention proposes a power supply device for a traveling wave tube, wherein a lead wire of a next winding is covered with a shield member, and the shield member is connected to a cathode terminal of the traveling wave tube.

[0008]

The lead wire of the secondary winding of the transformer is covered with a shield, and this shield is connected to the cathode output terminal of the reference potential point. Since the capacitance is almost zero, the value of the high-frequency induced ripple of the output voltage is significantly reduced.

[0009]

FIG. 1 is a diagram showing a first embodiment of the present invention. The traveling wave tube power supply 8 includes a high frequency inverter 1, a transformer 3, and a high voltage generator 6. A high voltage circuit such as a rectifier circuit is accommodated in the high voltage generator 6, molded with silicone rubber 16, and the outer periphery is surrounded by a shield case 13.

Next, the structure will be described in detail. The high-frequency inverter 1 is connected to the primary winding 2 of the transformer 3 and has a frequency
High frequency of kHz is supplied. The secondary winding 4 of the transformer 3 is connected via lead wires 5 and 7 to a bridge rectifier circuit 17 composed of diodes 19, 21, 23 and 25. A capacitor 27 is connected in parallel to an output terminal of the bridge rectifier circuit 17, a positive output is connected to the terminal 31, and a negative output is connected to the terminal 29. The secondary winding of the transformer 3 is simultaneously connected to the capacitor 4
7, 49, 51, 53 and diodes 55, 57, 59, 61 are also connected to the multi-stage voltage doubler rectifier circuit 45. The negative output of the multistage voltage doubler rectifier circuit 45 is connected to the cathode output terminal 29 through the diode 21 in the bridge rectifier circuit 17, and the positive output is connected to the helix output terminal 33 via the diode 62. A capacitor 28 is connected between terminals 29 and 33.
Are connected to form a helical voltage ripple filter.

On the other hand, the traveling wave tube 43 comprises a filament 37, a cathode 39, a helix 36, and a collector 35. The filament 37 is supplied from an insulated power source (not shown), and the cathode 39 is connected to the cathode output terminal 29. ,helix
36 is connected to the helix output terminal 33, and the collector 36 is connected to the collector output terminal 31.

Here, the lead wires 5 and 7 of the secondary winding 4 of the transformer 3 are covered with a shield 9 and connected to a cathode output terminal 29 at a point 11. In the traveling wave tube power supply device 8 configured as described above, the high-frequency AC component that is induced from the secondary winding 4 of the transformer 3 and appears at the cathode output terminal 29 is, as shown in FIG. It is configured as an equivalent circuit that divides the AC source e by the floating capacitance Cs and the capacitance Co of the capacitor 28. In the embodiment shown in FIG. 1A, the stray capacitance Cs becomes almost zero due to the shield 9 connected to the cathode output terminal 29 serving as the reference potential point, so that the output ripple eo has an extremely small value.

Although not shown, the outer periphery of the shield 9 is covered with an insulating tube to reinforce insulation between the shield 9 and the through-hole 15 and to provide a space between the shield 9 and peripheral components. Reinforce insulation.

[0014]

Second Embodiment FIG. 2 shows a second embodiment of the present invention.
In FIG. 2, elements with the same reference numerals as those in FIG. 1 correspond to elements with the same reference numerals. Regarding the difference between the second embodiment and the first embodiment, first, a first collector 35 and a second collector 34 are provided as the collector electrodes of the traveling wave tube 43.
Two sets of power supplies are provided for these two sets of collector electrodes. (That is, the secondary winding 4 of the transformer 3 is provided with the intermediate tap 12.)

First, as a power source for the first collector 35, the secondary winding 4 of the transformer 3 is connected to the rectifier circuit 18 via the lead wires 5 and 7. Rectifier circuit 18 is composed of diodes 75 and 77
And a double-wave voltage rectifier circuit composed of capacitors 83 and 85. The negative output of the rectifier circuit 18 is connected to the cathode terminal 29, and the positive output is connected to the first collector terminal 31.

Next, as a power source of the second collector 34, the lead 5 and the lead 5 are connected through the intermediate tap 12 of the secondary winding 4 of the transformer 3.
14 and connected to the rectifier circuit 20. The rectifier circuit 20 is a double-wave voltage rectifier circuit composed of diodes 71 and 73 and capacitors 79 and 81. The negative output of the rectifier circuit 20 is connected to the cathode terminal 29, and the positive output is connected to the second collector terminal 30.

Here, the leads 5, 7, and 14 from the secondary winding 4 of the transformer 3 are covered with a shield 9, and the lead 5 is connected at points 10 and 11 on the shield 9. Use as part of the leader line. Then, the shield 9 is connected to the cathode output terminal 29.

In the second embodiment constructed as described above, the cathode output terminal whose shield 9 is the reference potential point is also provided.
Since the floating capacitance Cs becomes almost zero by being connected to 29, the output ripple eo becomes an extremely small value.

In the above-described embodiment, the insulating medium of the high-voltage generating section 6 is not limited to silicon rubber.
A thermoplastic resin such as an insulating oil, an insulating gas, or an epoxy resin can be used. Further, the present invention is not limited to a power supply for a traveling wave tube, and can be used as a power supply for another electron tube having electrodes floatingly charged at a high voltage.

[0020]

As described above, the present invention has the features as described above, so that the output ripple can be reduced in the traveling wave tube power supply device without increasing the capacitance of the output capacitor. Therefore, it is economical, the energy stored between the output terminals is small, and unnecessary rush current value to the traveling wave tube is limited, which is effective for preventing deterioration of the tube.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a traveling wave tube power supply device according to the present invention.

FIG. 2 shows a traveling wave tube power supply device according to a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... High frequency inverter 3 ... Transformer 5 ... Lead wire 6 ... High voltage generator 7 ... Lead wire 8 ... Power supply device for traveling wave tube 9 ... Shield 12 ... Middle tap 13 ... Shield case 14 ... Lead wire
16 ... Silicon rubber 17 ... Bridge rectifier circuit 19,21,23,25 ... Diode 27 ... Capacitor 29 ... Cathode output terminal 31 ... (First) collector output terminal 33 ... Helix output terminal 34 ... Second collector 35 ... (First ) Collector 36 ... Helix 37 ... Filament 39 ... Cathode 41 ... Ground 43 ... Traveling wave tube 45 ... Multistage voltage doubler rectifier 47,49,51,53 ... Capacitor 55,57,59,61,62 ... Diode 71,73 , 75,77… Diode 79,81,83,85… Capacitor Cs… Stray capacitance

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takashi Yamashita 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Mikio Yamasaki 1-1 1-1 Uchisaiwaicho, Chiyoda-ku, Tokyo No. 6 Inside Nippon Telegraph and Telephone Corporation (72) Nobuhiro Takahashi Investigator, Nippon Telegraph and Telephone Corporation Takashi Kimoto, 1-16-1 Uchisaiwai-cho, Chiyoda-ku, Tokyo (56) References JP-A-5-276754 (JP) , A) Fully open 1988-33389 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02M ^7/ 00-7/40 H01J 23/34 H02M 1/12

Claims (1)

(57) [Claims] 1. A transformer driven by a high-frequency inverter, a first rectifier circuit connected to a secondary winding of the transformer, and a traveling wave tube connected to an output terminal of the first rectifier circuit. And a second rectifier circuit connected to the secondary winding of the transformer.
In one embodiment, one end of the output terminal of the rectifier circuit is connected to the cathode terminal of the traveling wave tube, and the other end of the output terminal is connected to the helix of the traveling wave tube. A power supply device for a traveling wave tube, wherein a lead wire of a next winding is covered with a shield member, and the shield member is connected to a cathode terminal of the traveling wave tube.