JPS63136812A - Pulse generating device - Google Patents

Abstract

PURPOSE:To use the titled device to a modulator with high PRF(pulse repetitive frequency) by constituting an inductive circuit element with a parallel connection circuit of a coll which controls a first transition of a pulse current and a satura ble reactance which controls a discharge current in terms of time. CONSTITUTION:A DC current is supplied to a line type pulse generating device from a DC power source 1 through a series connection circuit consisting of a charging choke 2 and a diode 3 and a trigger pulse is given to a switching element 4 to be ON. By charges accumulated in the capacitor of a pulse forming circuit 5 and electromotive forces generated in the coil of the pulse forming circuit 5, the coil 8 and the saturable reactance 9, the current Ip is discharged in an opposite direction. And the discharge current Ip flows through the coil 8 until the saturable reactance 9 is saturated. By means of the current Ip and energy by the trigger, the switching element 4 increases the diffusing speed of a carrier and expands the connection area in a short time. At this time the saturable reactance is saturated and a high current flows and then the high-current which passes through the saturable reactance 9 becomes zero when electric energy supplied from the DC power source 1 is consumed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a line type pulse generator used in radar equipment, etc., and in particular, the current upper ratio (di/dt: i is The present invention relates to a line-type pulse generator that controls current (t is time) to optimally operate switching elements.

(Prior Art) Conventional line-type pulse generators are widely used as pulse generators for driving pulse modulation type transmitting tubes such as magnetrons, talistrons, and traveling wave tubes. Furthermore, although thyratrons have been used as switching elements, solid-state elements such as SCRs and transistors are increasingly being used due to problems such as longevity.

Generally, a thyratron uses a heater/reservoir application method, and since the electron emission rate of the cathode is fast, a large current increase rate (di,/dt) at the rising edge of the pulse current can be achieved. However, in the case of solid-state devices, when a trigger is applied due to the internal structure, it takes time for the carriers to diffuse and the conduction area to become sufficiently large, so the current increase rate (di/dt) at the rising edge of the pulse current must be set high. There is a drawback that there is no

As a method to solve these drawbacks, the method shown in Fig. 2 (a)
There is a method in which a coil is placed in series in the discharge circuit, as in the case of the pulse generator shown in Figure 3(a), and a saturable reactor is placed in series in the discharge circuit, as in the case of the pulse generator shown in Fig. 3(a). Methods such as adding .

(Problems to be Solved by the Invention) The pulse generator shown in FIG. 2(a) described above uses a method that uses the coil 8 to reduce the slope of the rising portion of the pulse current, that is, the current increase rate (di/dt). be. However, if the current increase rate (di/dt) is too low, there are the following drawbacks.

■The pulse width becomes wider, resulting in shorter pulses and higher PRF (
It cannot be used as a modulator for pulse repetition frequency).

■The fill section generates a lot of heat.

(2) It is necessary to set the pulse width of the pulse shaping circuit in consideration of the inductance of the filler 8.

The pulse generator shown in FIG. 3(a) uses a saturable reactor 9 to apply a trigger and, after carrier diffusion time has elapsed, saturate the coil capacitance and cause a pulse current to flow. It also has the following drawbacks:

■When the saturation characteristics are good (as shown in Fig. 3) The pulse current is generated after the carrier diffusion time and is not suitable for high PRF.

■If the saturation characteristics are poor (Fig. 3 ■) (2-1) A reactor with the characteristics of a saturable reactor as shown in can't flow.

(2-2) The amount of saturation reactor is large and heat generation is large.

(2-3) The saturation reactor is large and the pulse width is wide.

(Means for Solving the Problems) A pulse generator according to the present invention includes a two-terminal circuit consisting of an inductive circuit element, a pulse shaping circuit network, and a load connected in series, and a pulse generator connected in parallel to the two-terminal circuit. A DC power source supplies power to the two-terminal circuit, and when the switching element receives a transmission trigger and opens and closes, a pulse is generated in the closed circuit consisting of the two-terminal circuit and the switching element. A line-type pulse generator that generates a current, characterized in that the inductive circuit element consists of a parallel connection circuit of a coil that controls the rise of the pulse current and a saturable reactor that temporally controls the discharge current. .

(Example) Embodiments of the present invention will be described with reference to the drawings.

FIG. 1(a) is a block circuit diagram showing one embodiment of the present invention, and FIG. 1(b) is a waveform diagram showing various signals of this embodiment. This embodiment is a two-terminal circuit in which a parallel connection circuit of a coil 8 and a saturable reactor 9, a pulse shaping circuit 5, and the primary side of a transformer 6 with a load 7 connected to the secondary side are connected in series. This is a line type pulse generator in which switching elements 4 are connected in parallel. A DC current is supplied from the DC current R1 to the line-type pulse generator through a series connection circuit of a charging choke 2 and a diode 3, and a trigger pulse is applied to the switching element 4 to turn it on, so that the capacitor of the pulse shaping circuit 5 is completely stored. charge and the fill and coil 8 of the pulse shaping circuit 5. Due to the electromotive force generated in the saturable reactor 9, the current Ip is discharged in the opposite direction. Thus, the discharge current Ip flows through the coil 8 until the saturable reactor 9 is saturated. With this current Ip and energy from the trigger, the switching element 4 increases the carrier diffusion rate and increases the conduction area in a short time, at which point the saturable reactor is saturated and a large current flows.
When the electrical energy supplied from the DC current fil is turned on, the large current passing through the saturable reactor 9 becomes zero.

The waveform of the current Ip in this case is as shown by the solid line in FIG. 1(b), and is a desired pulse waveform. The process will be explained below.

11ffl(a), when the coil 8 is removed and the device operates as a line type pulse generator having only the saturable reactor 9, the current waveform corresponding to the discharge current Ip is shown in FIG. 1(b). It can be shown by Similarly, in FIG. 1(a), when the saturable reactor 9 is removed and the device is operated as a line-type pulse generator having only the coil 8, the current waveform corresponding to the discharge current Ip is as shown in FIG. 1(b). ) is shown by the current waveform ■. By combining the current waveforms ■ and ■, the current waveform with the current flowing through the coil 8 as zero is the current waveform from the time when the saturated current starts flowing in the saturable reactor 9 until the next trigger pulse arrives. This is the solid line portion of the Ip current waveform in FIG. 1(b). In this way, the switching element 4 remains off until the next transmission trigger is received after the discharge current Ip becomes zero. Therefore, the load 7 is connected to the I of FIG. 1(b) via the transformer 6.
After the pulse current of the p current waveform is completely supplied, the above operation is repeated. In this way, the optimum value can be set for each device.
The saturation characteristics of the saturable reactor 9 and the value of the coil 8 are determined.

The present invention can solve problems such as abnormal heat generation, high PRF radar equipment, and pulse width selection, and the present invention can be easily applied to pulse generators.

(Effects of the Invention) As explained above, the present invention connects the parallel circuit of the coil 8 that controls the discharge current Ip and the saturable reactor 9 that saturates after the switching element 4 reaches a sufficient conduction area to the discharge circuit. The switching element 4 is inserted in series to operate the switching element 4 optimally. The present invention has such effects.

[Brief explanation of the drawing]

FIG. 1(a) is a block circuit diagram showing an embodiment of the pulse generator of the present invention, FIG. 1(b) is a waveform diagram of various signals in the embodiment of FIG. 1(a), and FIG. a), Figure 3 (
a) is a block circuit diagram of a conventional pulse generator, and FIGS. 2(b) and 3(b) are respectively shown in FIG. 2(a).
, is a waveform diagram of signals of various parts in the device of FIG. 3(a). 1. DC power supply, 2.
3... Diode, 4... Switching element, 5...
...Pulse shaping circuit, 6...Transformer, 7...Load,
8... Fill, 9... Saturable reactor.

Claims (1)

[Claims] A two-terminal circuit consisting of an inductive circuit element, a pulse shaping circuit network, and a load connected in series, and a switching element connected in parallel to the two-terminal circuit, and power is supplied to the two-terminal circuit from a DC power source. In the line type pulse generator, the inductive circuit element generates a pulse current in a closed circuit consisting of the two-terminal circuit and the switching element by opening and closing the switching element that receives a transmission trigger. 1. A pulse generator comprising a parallel-connected circuit of a coil that controls the rise of the current and a saturable reactor that temporally controls the discharge current.