JP2007189800A - Pulse power supply - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pulse power supply in which bouncing ripple current of an upstream power supply is reduced in order to enhance the performance of a radar. <P>SOLUTION: The pulse power supply comprises a constant current circuit 11, a DC/DC converter 12, and a choke coil 13 and a capacitor 14 connected in series therewith. When an output load feeds a pulse current, a current exceeding the limit current of the constant current circuit 11 is supplied from the capacitor 14 in addition to the current supplied from the constant current circuit 11 at the input section. When the output load is turned off, the capacitor 14 is charged from the constant current circuit 11. Bouncing ripple current to the input voltage can be limited by a capacitor 14 of small capacity because of the constant current circuit 11. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates generally to pulse power supplies, and more particularly to a pulse power supply apparatus that applies a pulse voltage to a radar transmission / reception module.

  Conventionally, when a radar device is connected to a pulse power supply as a load, a load current flows at the repetition frequency used by the radar, so that a ripple occurs in the voltage of the connected pulse power supply and further ripples to the upstream primary power supply device. May return, causing high-frequency loss of the primary power supply and waveform distortion of transmission and reception. The return of the ripple to the primary power supply device is called a bounce ripple current. This bounce ripple current is several kHz at high frequencies.

  Conventionally, in order to solve such a problem of the bounce ripple current, a filter composed of an expensive transformer and a large-sized low-impedance large-capacitance capacitor has been arranged in the power supply to reduce the influence of the ripple. However, when such a power supply is used, there is a drawback that the pulse power supply device is enlarged.

As a technique for preventing a ripple current from being generated at the time of transmission / reception of a radar apparatus, as disclosed in Patent Document 1, there is a technique in which power is supplied from a large-capacity capacitor by switching with a switch at the time of transmission / reception of the radar apparatus. However, as described above, it is necessary to prepare a capacitor having a low impedance and a large capacity, which is not suitable for cost reduction and miniaturization. Also, placing a capacitor with a large capacity was not an essential solution.
Japanese Patent No. 2726356

  The present invention has been made in view of the problems of the conventional pulse power supply device as described above, and an object of the present invention is to provide a pulse power supply device that has a small rebound ripple current to the upstream power supply device. is there.

  In order to solve the above problem, according to claim 1 of the present invention, a constant current source, a DC / DC converter, a choke coil, and a capacitor are provided, and the constant current source and the DC / DC converter include: The choke coil is connected in series, and the capacitor is connected in parallel to the input of the DC / DC converter. The current corresponding to the power consumption of the load connected to the DC / DC converter is There is provided a pulse power supply device characterized in that a constant current source is passed through the DC / DC converter.

  According to a second aspect of the present invention, a constant current circuit connected to a DC power source having a voltage fluctuation, a DC / DC converter connected to the constant current circuit and supplying a pulse current to a load, and the DC A choke coil connected in series between the DC / DC converter and the constant current circuit, and a capacitor connected in parallel to the input of the DC / DC converter, the output current of the constant current circuit is the load The pulse power supply apparatus is characterized in that an average current corresponding to the magnitude of the power consumption supplied to is supplied to the DC / DC converter.

  According to the present invention, since the output pulse current returns to the input side is greatly reduced, a high-performance pulse power supply device that is small and inexpensive and that does not allow a high-frequency ripple current to flow through the input voltage source can be realized.

  Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 shows a circuit configuration of a pulse power supply device according to an embodiment of the present invention. The pulse power supply circuit of this embodiment includes a constant current circuit 11, a DC / DC converter 12, a choke coil 13 connected in series therebetween, and a capacitor 14 connected in parallel.

  A DC power source 21 having a voltage variation is connected to the input side of the constant current circuit 11. The constant current circuit 11 connected to the DC power supply 21 forms a chopper circuit with a constant current limit. The capacitor 22 connected in parallel to the DC power supply 21 and the + side of the DC power supply 21 are connected to the input section. A choke coil 25 connected on the opposite side to the anode of the switch 23 and the rectifier diode 24, and a capacitor 26 connected at one end to the cathode side of the rectifier diode 24, on the opposite side of the capacitor 22 and the switch circuit 23. Both terminals are commonly connected to the negative side of the DC power supply 21 on the input side.

  A capacitor 14 is connected in parallel to the DC power source 21 on the opposite side terminal of the choke coil 13 and the choke coil 25 on the positive side of the output side capacitor 26 of the constant current circuit 11 to form a filter circuit.

  Further, a DC / DC converter 12 is connected to the subsequent stage of the capacitor 14. This DC / DC converter 12 is constituted by a bridge type DC / DC converter, and is connected to a switch section constituted by four switches 27, 28, 29, 30 and a middle point of the switches 27, 28 and 29, 30. A full-wave rectifier circuit composed of diodes 32, 33, 34, and 35 is connected to the primary side and the secondary side of the transformer 31. A capacitor 37 is connected in parallel to the + terminal of the full-wave rectifier circuit and to the terminal opposite to the choke coil 36. A load 38 for supplying a pulse current is connected to both ends of the capacitor 37.

  FIG. 2 shows waveforms of respective parts of the pulse power supply device according to the embodiment of the present invention shown in FIG. The operation of the above embodiment will be described with reference to FIG. Here, the current output from the DC power source 21 is Idc, the current output from the constant current circuit 11 is Ic, the input voltage of the DC / DC converter 12 is Vc, the input current is Io, and the output voltage of the DC / DC converter 12 is output. Is Eo, and its load current is Ip.

  FIG. 2A shows the state of the current Ip supplied from the DC / DC converter 12 to the load. It is assumed that a load having a pulse width Tp is repeated in the pulse period T. Naturally, the pulse power supply device needs a pulse response necessary for the radar device. At this time, the bridge type DC / DC converter 12 operates so that the output voltage becomes constant, and as shown in FIG. 2B, the input voltage Vc of the converter varies from V1 to V2.

  The input voltage control voltage of the DC / DC converter 12 is required to be wider than the range from the voltage value V1 to the voltage value V2 shown in FIG. Without the constant current circuit 11 as in the prior art, this voltage ripple may return to the upstream power supply. It is necessary to supply a large pulsed current to an RF element such as a radar. Conventionally, in order to reduce this ripple, a pulsed current is obtained by connecting a capacitor having a large capacity directly to the output of the DC power supply 21 in parallel. Was supplied from this capacitor, and the ripple of current was reduced by the simple principle that the capacitance was large.

  In the pulse power supply device of the present invention, by adding the constant current circuit 11 upstream of the DC / DC converter 12, when the output load flows a pulse current, in addition to the current supplied from the constant current circuit 11 of the input unit, The current exceeding the current limited by the constant current circuit 11 is supplied from the capacitor 14.

  For a current exceeding the current limited by the constant current circuit 11, the voltage Vc of the capacitor 14 decreases and fluctuates. When the output load is turned off, the capacitor 14 is charged from the constant current circuit 11. It can be seen that the voltage fluctuates between V1 and V2 depending on the load current (FIG. 2B).

  Next, the current setting of the constant current circuit 11 will be described. If the peak of the load current is Ip and the pulse width is Tp, the charge amount of one pulse is Q = Ip · Tp. Therefore, the average current is Iave = Ip · Tp / T.

In the circuit configuration shown in FIG. 1, energy input from the constant current circuit 11 to the DC / DC converter 12 is considered for one period T. Assuming that Ic flows during the load pulse width Tp and the capacitor 14 is charged from V1 to V2 when OFF, the following occurs.

The output energy of the bridge type DC / DC converter 12 is Iave · T + Wd (2)
Here, C is the capacitance of the capacitor 14 and Wd is the loss of the DC / DC converter.

  Since both sides are equal from the energy conservation law, the output current Ic of the constant current circuit 11 can be determined by setting the equations (1) and (2) equal. Assuming that Ic thus obtained is set in the constant current circuit 11, the converter current Io is as shown in FIG. 2 (c), and Ic is a current with low ripple as shown in FIG. 2 (d). Therefore, the output current Idc of the constant current circuit 11 is constant, and the bounce ripple current can be reduced.

  As can be understood from the equation (1), when C is reduced, the second term is reduced, but the first term can be increased. The bounce ripple current to the input voltage can be limited.

  According to the embodiment of the present invention described above, since the output pulse current is greatly reduced to the input side, it is small and inexpensive and has a high performance pulse power source that does not cause a high-frequency ripple current to flow through the input voltage source. A device can be realized.

  The present invention is not limited to the above-described embodiments, and can be variously modified and embodied without departing from the scope of the invention in the implementation stage. For example, in the above-described embodiment, a non-insulated step-up chopper type constant current source is used, but an insulating type DC / DC converter can also be used. In the above-described embodiment, the DC / DC converter connected in the subsequent stage has been described as an insulated bridge converter. However, a non-insulated bridge converter can also be used.

It is a circuit block diagram of the pulse power supply device in one Example of this invention. It is a figure explaining operation | movement of the pulse power supply device in one Example of this invention.

Explanation of symbols

11 ... constant current circuit,
12 ... DC / DC converter,
13 ... Choke coil,
14: Capacitor,
21 ... DC power supply,
22, 26, 37 ... capacitors,
23 ... switch,
24, 32, 33, 34, 35 ... diodes,
25, 36 ... choke coil,
27, 28, 29, 30 ... switch,
31 ... Trans,
33 ... Choke coil for rectifier circuit,
38 ... Load.

Claims (3)

A constant current source, a DC / DC converter, a choke coil, and a capacitor are provided.
The choke coil is connected in series between the constant current source and the DC / DC converter, the capacitor is connected in parallel to the input of the DC / DC converter, and the load is connected to the DC / DC converter. A current corresponding to the magnitude of the power consumption is caused to flow from the constant current source to the DC / DC converter. A constant current circuit connected to a DC power supply having a voltage variation;
A DC / DC converter connected to the constant current circuit and supplying a pulse current to the load;
A choke coil connected in series between the DC / DC converter and the constant current circuit;
A capacitor connected in parallel to the input of the DC / DC converter;
An output current of the constant current circuit is set so that an average current corresponding to a magnitude of power consumption supplied to the load is supplied to the DC / DC converter.   The pulse power supply device according to claim 1, wherein the DC / DC converter is a bridge type converter.

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