JPS61148916A - Intermitting circuit - Google Patents

Abstract

PURPOSE:To operate incorporatedly a thyristor and a transistor by utilizing a certain kind of characteristic of the transistor and the thyristor in a 3-terminal thyristor where transistors (TRs) are connected in cascade. CONSTITUTION:A TR is a current active element utilizing a leakage current of the base. On the other hand, the 3-terminal two-way thyristor TC is a voltage active switch element having a positive feedback operation. A switch SW is connected between a base terminal B of the TR and a gate G of the thyristor TC. Then the base B and the gate G are switched to apply a negative feedback capacity of the TR in matching with a switch voltage is fed from the gate G. Thus, the holding current of the thyristor TC is fed by the emitter current of the TR to intermit a DC voltage. Thus, the TR and the thyristor are operated incorporatedly.

Description

[Detailed description of the invention] By utilizing the special properties of certain types of transistors, the transistor and a three-terminal thyristor connected in cascade are operated in an integrated manner by the bias voltage of the transistor. circuit.

Conventionally, a three-terminal thyristor with transistors connected in series was used, but since it was not possible to operate the transistor and the thyristor in an integrated manner, for example, each was driven in synchronization. Therefore, there is a risk that the supply voltage source impedance and the thyristor may interfere with each other, and in order to obtain a stable thyristor holding current, delicate control is required, the circuit becomes complex, and the reliability exceeds a certain level. was not obtained.

The present invention has been made in view of the above-mentioned problems, and has been solved by utilizing the special properties of certain types of transistors. In other words, the transistor and the cascade-connected three-terminal thyristor are operated together using the bias voltage of the transistor, and the supply voltage source and the three-terminal thyristor are separated, making it possible to stably intermittent the supply voltage source. . From this, the above-mentioned problems were solved, a stable ON operating point and a predetermined OFF operating point were obtained, and advantages such as a unique new inverter function were obtained.

The details will be described below with reference to the drawings.

FIG. 1 shows one basic diagram of the invention.

The operation will be explained with reference to FIG.

The TR is a transistor (hereinafter simply referred to as a transistor) that has certain special properties and is a current active element. The terminals are collector (C) control type (base) (B),
It has an emitter (E). The TC is a three-terminal bidirectional thyristor (hereinafter simply referred to as a thyristor), typically a three-terminal thyristor, and is a voltage active element having a positive feedback action. The terminal has positive polarity (T2), control pole (gate) (G
) and a negative polarity terminal (T1), each of which is led out. The emitter terminal (E) and the positive polarity terminal (T2) are connected in cascade. A switch (SW) is connected between the base terminal (B), which is the control pole of the transistor (TR), and the gate terminal (G), which is the control pole of the three-terminal thyristor (TC).

And between the collector terminal (C) and the base terminal (B),
Connect a resistor (R1) (constituting a self-bias circuit). By connecting and configuring in this way, it is possible to make use of the special properties of a certain type of transistor (TR), and the following operation can be obtained.

The functions of the above transistor (TR) will be described in order.

For example, when a full-wave rectified commercial frequency voltage is applied to the collector terminal (C) and negative polarity terminal (■) with the switch (SW) open and the thyristor (TC) off, the base voltage will change. A voltage between the emitter and the negative terminal (E/T1) proportional to the size is supplied to the thyristor (TC). This is because the emitter terminal (E) is opened by turning off the thyristor (TC), which has a positive feedback action, so the base leakage current of the transistor (TR) acts, and the base voltage is applied. Thyristor (
TC) main circuit (T2/T1) voltage is supplied.

From this, the bias voltage of the transistor (TR) generated by opening and closing of the switch (SW) can be applied to the thyristor (T).
C) was made possible to trigger Trigalleon.

Next, the function of the switch (SW) will be described.

A bias voltage is supplied to the base terminal (B) and the gate terminal (G) by controlling the opening and closing of the switch (SW). That is, the bias voltage is applied to the main circuit (T2/T1) voltage of the thyristor (TC) using the leakage current of the base mentioned above, and the bias voltage is applied to the gate terminal (G
). At both these voltages, the bias voltage loop (B・E・G・S) of the transistor (TR)
W), the thyristor (TC) is triggered, and an on-current flows. Since the trigger mode is selected, a portion of the above-mentioned on-current flows to the gate terminal (G). That is, a base current proportional to the aforementioned bias voltage flows between the emitter (E) and the gate (G), and the transistor (T
R) is turned on. The emitter current corresponding to the base current flows following the on-state current of the thyristor (TC) described above, thereby supplying the holding current of the thyristor (TC). Due to the decrease in the bias voltage mentioned above, when the base current stops flowing, the emitter current becomes less than the holding current value of the thyristor (TC), and the thyristor (TC) has a positive feedback effect.
turns off. Therefore, the emitter terminal (E) is opened and the transistor (TR) is turned off. That is, the thyristor (TC) cuts off the negative feedback capacitance of the transistor, and by flowing the base current described above, an emitter current that is less than the holding current value is supplied, the thyristor (TC) is turned off, and the transistor (TR) is turned off. The supply voltage is
In this way, the thyristor (TC) cuts off the emitter current, which is converted into the output current of the transistor (TR), quite naturally, thereby stably intermittent the supply voltage source. Note that the output current is borne by the transistor (TR), and the output voltage is borne by the thyristor (TC). From this, the direct current amplification factor gain (hF
E) and the switch (SW) circuit, the thyristor (TC) can be turned on with the gate voltage current of the current vector within the region without mistry, the desired pace current will flow, and the variable output current can be adjusted. It was possible to obtain

FIG. 2 is a diagram of one embodiment.

R3 is a gate input limiting resistor, which forms a voltage dividing circuit with a stabilizing resistor (R2), and defines the output impedance with respect to the gate current. D1 is a protection diode, which is added as shown in FIG. 1 and connected as shown.

A bias voltage having a phase relationship between the main circuit voltage and the gate voltage is created by the resistor (R2) and the resistor (R3).

Utilizing this function, if the magnitude of the gate voltage is sequentially changed and the thyristor (TC) is turned on, the thyristor (TC) will turn on in proportion to the magnitude of the gate voltage under conditions considered to be due to the residual charge of the thyristor ) changes sequentially. That is, this change in the turning-on operating point, regardless of the supply voltage, allows a variable output voltage to be obtained. This makes it possible to obtain the desired variable voltage and current, and to obtain a variable frequency voltage and current output. For example, it is convenient for inductive loads that require starting current.
Generates completely unique inverter function.

Note that various circuits can be used for the switch (SW) and the resistor (R2) depending on the characteristics of the load and the trigger mode of the thyristor.

As mentioned above, by taking advantage of the special properties of certain transistors, we create a new current-voltage active element, obtain a series of predetermined operations following a stable on-operation point, and achieve a predetermined result. The off operating point was obtained. This prevents malfunctions and noise generation, separates the supply voltage source from the three-terminal thyristor, and stably connects and disconnects the supply voltage source. As a result, we have eliminated chattering, greatly reduced heat generation from loads, etc., and created a new inverter function. Therefore, it can be used in disassembly of power control, light control, etc. in addition to existing thyristor and transistor application fields.

[Brief explanation of drawings]

In the drawings, FIG. 1 shows one basic diagram of the invention. Second
The figure shows one example. In addition, in the symbol, TR is a transistor with certain special properties. TC is a three-terminal bidirectional thyristor, typically a three-terminal thyristor. R
1 is bias resistance. SW is a switch. R3 is a gate input limiting resistor. R2 is a stabilizing resistor.

Claims (1)

[Claims] (1) A transistor and a three-terminal thyristor are connected in cascade, and the bias voltage of the transistor generated by switching between the control terminal of the transistor and the control terminal of the three-terminal thyristor is used to control the cascade-connected three-terminal thyristor. An intermittent circuit characterized in that the transistor is turned on and the holding current of a three-terminal thyristor in cascade connection is supplied by turning on the transistor.