JP2769280B2 - Thyristor converter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thyristor converter having two functions of a single-phase full-wave rectification bridge system and a single-phase mixed rectification bridge system.

[0002]

2. Description of the Related Art FIG. 9 is a circuit diagram of a single-phase full-wave bridge rectifier showing an example of a conventional thyristor converter.
In FIG. 9, TH1 to TH4 are thyristors, U and V are AC input terminals, and P and N are DC output terminals. The AC input terminals U and V are connected to an intermediate point between the thyristors TH1 and TH2 and an intermediate point between the thyristors TH3 and TH4, respectively. The thyristors TH1 and TH3 are both connected to a DC output terminal P, and the thyristors TH2 and TH4 are both connected to a DC output terminal N. DC output terminals P,
A load, for example, a field winding LF of a DC motor DCM is connected between N. 20 is a thyristor TH1 to T
This is a control circuit for supplying a gate signal to the gate of H4. Each thyristor is fired and its phase is controlled by this gate signal. As a result, the thyristor converter 1
0 generates a variable DC output voltage at the DC output terminals P and N. Then, a DC voltage is supplied from the DC output terminals P and N to a DC load such as a field winding LF of the DC motor DCM. FIG. 10 is a circuit diagram of a single-phase mixed-bridge rectifier showing another example of the conventional thyristor converter. In FIG. 10, D1 and D2 are diodes, and the thyristors TH3 and TH4 of the device in FIG. 9 are replaced with diodes D1 and D2. FIG. 11 is an example of a control circuit for controlling a single-phase mixed-bridge rectifier circuit. The control circuit 20 converts the current flowing from the DC output terminal P to N to DC
Detect by CT. The comparator (CP) 10 is a DCC
The DC current detected at T is input via a resistor R11, and this input signal is compared with a set value input via resistors R13 and R12, and the comparison result is obtained via a gate pulse generator G or a thyristor via a pulse transformer. The thyristors are supplied to the gate terminals of TH1 and TH2 to fire and control the phase.

FIG. 12 is a waveform diagram during operation of the thyristor converter shown in FIG. 11A shows a waveform of an AC input voltage applied between input terminals U and V,
(B) is an output of the control circuit 20, which is the thyristors TH1 to T
The waveform of the thyristor gate signal applied to the gate of H4, (c) is the waveform of the DC output phase-controlled, and (d) is the waveform of the DC load current flowing through the load LF. FIG.
11 is a waveform chart showing the operation of the thyristor conversion device shown in FIG. 13A shows a waveform of an AC input voltage applied between input terminals U and V, and FIG.
A waveform of a gate signal applied to the gates of the thyristors TH1 and TH2 at an output of 0, (c) is a waveform of a phase-controlled DC output voltage, and (d) is a waveform of a DC load current Id flowing through the load LF. . FIG. 14 shows the relationship between the phase control angle α and the DC output voltage in each of the above methods.

Next, the operation of the thyristor converter according to the conventional example will be described. In FIG. 9, an AC voltage input from AC input terminals U and V ((a) of FIG. 12)
Is converted into a DC voltage by the phase control of the thyristors TH1 to TH4 and output from the DC output terminals P and N. This DC output voltage ((c) in FIG. 12) is supplied to the load LF, and a DC load current ((d) in FIG. 12) flows through the load LF. At this time, the thyristors TH1 to TH4 receive a gate signal having a phase as shown in FIG.

[0005]

Since the conventional thyristor conversion device is configured as described above, for example, in the case of a single-phase full-wave bridge type, as shown in FIG. DC output voltage Ed is positive 0.9 × Eac
From (V) to negative -0.9 x Eac (V). That is, in this case, power can be regenerated to the AC input side, and this is effective when, for example, it is desired to rapidly reduce the output current. However, as shown in FIG.
There is a disadvantage that the ripple of the DC output voltage increases, and as a result, the ripple rate of the DC load current Id also increases.
On the other hand, in the case of the single-phase mixed bridge type, the output voltage Ed changes from a positive 0.9 × Eac (V) to 0 due to the phase control angle α.
Can only change up to. That is, in this case, it is impossible to regenerate power to the AC input side. Therefore, there is a disadvantage that it is difficult to rapidly reduce the output current. However, as shown in FIG. 13C, there is an advantage that the ripple of the output voltage is small, and as a result, the ripple ratio of the output current is also small.
Thus, in applications requiring rapid current control, a single-phase full-wave bridge type, a device with a relatively slow current response or a device with a constant current control and a small current ripple ratio are required. In such applications, a single-phase mixed-bridge converter is used, and a conversion device is selected and used according to the application. For this reason, it is necessary to prepare and manufacture the above two types of devices, and there is a problem in that the number of parts increases, and the manufacturing management of the device becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has a single configuration to provide the function of either the single-phase full-wave bridge system or the single-phase mixed bridge system. An object of the present invention is to provide a thyristor conversion device that can be selectively used.

[0007]

As shown in FIG. 1, the thyristor conversion device according to the first invention has a gate terminal g3 of each thyristor in one of the series circuits A and B of the thyristor. , G4 (or g1, g2)
And phase control terminals 2a and 2b which are output terminals of the control circuit.
Are connected, and switches SA3 and SA4 are provided to switch between connecting the anodes a3 and a4 of each thyristor via a series circuit of a resistor and a diode.

As shown in FIG. 3, the thyristor converter according to the second invention has two thyristors TH2 between one of the DC output terminals P and N and both of the AC terminals U and V. , gate of each TH4 (or TH1, TH3)
The phase control terminals 2a and 2b, which are output terminals of the control circuit, are connected to the G terminals g2 and g4 (or g1 and g3) , or the thyristor TH is connected via a series circuit of a resistor and a diode.
2, anodes a2 , a of TH4 (or TH1, TH3)
4 (a1, a3) switch SA for switching whether to connect
2, SA4.

As shown in FIG. 5, the thyristor conversion device according to the third aspect of the present invention includes, in two series circuits of thyristors, each gate terminal g3 of two thyristors of any one series circuit. g4 (g1, g2) or two thyristors TH2, TH4 (TH1, TH2) between one of the DC output terminals and both AC input terminals U, V.
3) to each gate terminal g2, g4 (g1, g3)
Switches SA3 and SA4 are provided for switching between supplying a normal phase control signal 2m output from the control circuit and supplying a phase control signal 2n having a firing phase angle of 0 °.

In the thyristor converter according to the fourth aspect of the present invention, as shown in FIG. 6, a circuit for outputting a normal phase control signal includes a control transformer for obtaining control voltages having the same phase and opposite phase as the main circuit voltage. About 90 ° from the in-phase control voltage
A phase delay circuit for obtaining a phase voltage Ec of a phase delay, a comparator for comparing the phase voltage Ec with a control voltage Es for phase control, a differentiation circuit for differentiating an output of the comparator, and an output of the differentiation circuit And a circuit for outputting a phase control signal having a firing phase angle of 0 ° between the output terminal v of the control voltage having the opposite phase to the main circuit voltage and the terminal 2 of the switch. The ignition thyristor is provided with a lead circuit that obtains a phase lead current from a control voltage having a phase opposite to that of the main circuit voltage and supplies a gate current of the ignition thyristor.

In the thyristor converter according to the fifth aspect of the present invention, as shown in FIG. 8, a switch SA for selectively switching between connecting and not connecting a diode between the DC output terminals P and N is provided. Was.

[0012]

The thyristor converter according to the first aspect of the present invention
In a state where the device is stationary, the gates g3 and g4 (or g4) of the respective thyristors are switched by the switches SA3 and SA4.
1, g2) are connected to the phase control terminals 2a, 2b, which are output terminals of the control circuit, or the anodes a3, a4 of each thyristor are connected via a series circuit of a resistor and a diode. And it is used as a single-phase full-wave bridge or a single-phase mixed bridge depending on the application.

The thyristor conversion device according to the second aspect of the present invention provides the switching devices SA2 and SA4 while the device is stationary.
, Two thyristors TH2 between one of the DC output terminals P and N and the two AC input terminals U and V
Gate terminal g of each of TH4 (or TH1, TH3)
2, g4 (or g1, g3) are connected to the phase control terminals 2a, 2b, which are the output terminals of the control circuit, or the respective thyristors TH2, TH are connected via a series circuit of a resistor and a diode.
4 (or TH1, TH3) is switched between connecting the anodes a2 , a4 ( or a1, a3). The single-phase full-wave bridge is used as a single-phase mixed bridge depending on the application.

The thyristor conversion device according to the third aspect of the present invention provides the switching devices SA3 and SA4 while the device is stationary.
, Two gate terminals g3, g4 (g1, g2) or two of the thyristors of any one series circuit between one of the DC output terminals and the two AC input terminals U, V Thyristors TH2, TH4 (TH1, TH
3) to each gate terminal g2, g4 (g1, g3)
It switches between supplying the normal phase control signal 2m, which is the output of the control circuit, and supplying the phase control signal 2n having a firing phase angle of 0 °. And it is used as a single-phase full-wave bridge or a single-phase mixed bridge depending on the application.

In the thyristor converter according to the fourth aspect of the present invention, a circuit for outputting a normal phase control signal includes a control transformer for obtaining a control voltage having the same phase and an opposite phase as a main circuit voltage;
A phase delay circuit for obtaining a phase voltage EC having a phase delay of about 90 ° from the in-phase control voltage, a comparator for comparing the phase voltage EC with a control voltage ES for phase control, and differentiating the output of the comparator A normal phase control signal 2n is output by a circuit including a differentiating circuit for performing the above operation and a pulse amplifier for amplifying the output of the above differentiating circuit. Alternatively, a phase advance current is obtained from a firing thyristor provided between an output terminal v of a control voltage having a phase opposite to the main circuit voltage and a terminal 2 of the switch, and a control voltage having a phase opposite to that of the main circuit voltage. A phase control signal 2m for setting the ignition phase angle to 0 ° is output by a circuit including a lead circuit for supplying a gate current of the arc thyristor. By switching and using these phase control signals, they are used as a single-phase full-wave bridge or a single-phase mixed bridge depending on the application.

In the thyristor converter according to the fifth aspect of the invention, when the device is stationary, the switch SA selectively switches between connecting and not connecting a diode between the two DC output terminals P and N. And it is used as a single-phase full-wave bridge or a single-phase mixed bridge depending on the application.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Embodiment 1 FIG. FIG. 1 is a circuit diagram of a thyristor conversion device according to Embodiment 1 of the present invention, and FIG. 2 is a waveform diagram showing the operation thereof. In FIG. 1, RA3, RA4 and DA3, DA4
Is a resistor and a diode, and SA3 and SA4 are switches. Each resistor RA3 and diode DA3 are connected in series, and one end on the resistor side is connected to the anode a3 of the thyristor TH3. The switch SA3 has a common terminal C and switching terminals 1 and 2, the common terminal C is connected to the gate terminal g3 of the thyristor TH3, and the switching terminal 1 is connected to the phase control terminal 2b.
And the switching terminal 2 is connected to the cathode side of the diode DA3. Similarly,
The resistor RA4 and the diode DA4 connected in series have one end on the resistance side connected to the anode a4. The switch SA4 has its common terminal C connected to the gate terminal g4 of the thyristor TH4, its switch terminal 1 connected to the control circuit 20 via the phase control terminal 2a, and its switch terminal 2 connected in series to the diode DA4. Is connected to the sword side. When used as a single-phase full-wave bridge type, the switches thyristors SA3 and SA4
Switch terminals SA3 and SA4 in the same condition when the switching terminals of
Is connected to the second side. In this manner, a thyristor converter having two functions, a single-phase full-wave bridge and a single-phase mixed bridge, can be provided.

Next, the operation of the apparatus according to the first embodiment will be described. For example, when the switches SA3 and SA4 are selected on the switching terminal 1 side, a gate signal to the thyristors TH3 and TH4 is given from the output of the control circuit 20, and the thyristors TH3 and TH4 are described in FIGS. 9 and 12 described above. The same phase control as described above is performed. That is, the thyristor converter 10 operates as a single-phase full-wave bridge type. When the switches SA3 and SA4 are selected on the switching terminal 2 side, the waveform of the operation shown in FIG. 2 is obtained. In this case, when the anode potentials of the thyristors TH3 and TH4 become positive,
That is, at time (c) and (a) in FIG. 2, a gate signal having a phase as shown in FIG. 2 (b) is applied to each gate of the thyristors TH3 and TH4 via the respective resistors and the diodes RA3, RA4 and DA3, DA4. And this results in
The thyristors TH3 and TH4 are energized at a phase angle of 0 °, and perform the same operation as a diode. As a result, a DC output voltage as shown in FIG. 2C is obtained, and the thyristor converter 10 operates as a single-phase mixed-bridge type.

Embodiment 2 FIG. FIG. 3 is a circuit diagram showing a configuration of a thyristor conversion device according to Embodiment 2 of the present invention, and FIG. 4 is a waveform diagram showing an operation of the device. The device according to the second embodiment includes switching devices SA2, S
A4 and the use of the resistors RA2 and RA4 and the diodes DA2 and DA4 connected in series are the same as those in the first embodiment, but the positions where these are used are different. That is, in the switches SA2 and SA4, the common terminal C is connected to the gate terminals g2 and g4 of the thyristors TH2 and TH4, the switching terminal 1 is connected to the control circuit 20 via the phase control terminals 2a and 2b, and the switching terminal 2 Are anodes of thyristors TH2 and TH4 via diodes and resistors connected in series
a2 and a4. When the switches SA2 and SA4 are set to the switching terminal 1 side in this device, the device operates as a single-phase full-wave bridge type. Further, the switching devices SA2 and SA
When the switching terminal 4 is on the switching terminal 2 side, the operation waveform is as shown in FIG. In this case, each thyristor TH2, TH4
At the time when the anode potential becomes positive, that is, (c) in FIG.
And at the time of (a), each resistor and diode RA2,
A gate signal as shown in FIG. 4B is applied to the gates of the thyristors TH2 and TH4 via RA4, DA2 and DA4, and the thyristors TH2 and TH4 have a phase angle of 0.
It is energized at ° and behaves like a diode. At this time, each thyristor is energized during the firing period of the thyristor shown in FIG. 4C, the thyristors TH3 and TH4 are energized simultaneously in the section from (A) to (B), and from (C) to (D). In the section, the thyristors TH1 and TH2 are simultaneously energized. As a result, the output voltage between the DC output terminals P and N is obtained as shown in FIG. 4D, and the thyristor converter 10 operates as a single-phase mixed bridge type. In this embodiment, an example in which the switching operation is performed on the thyristors TH2 and TH4 has been described. However, a similar switching operation may be performed on the two thyristors TH1 and TH3 connected to the DC output terminal P.

Embodiment 3 FIG. FIG. 5 is a circuit diagram showing a thyristor conversion device according to Embodiment 3 of the present invention. In the first and second embodiments, the switch is provided outside the control circuit. In the third embodiment, the switch is provided inside the control circuit to perform a switching operation. In the figure, P
T1 to PT4 are pulse transformers, the secondary windings of which are respectively thyristors TH1 to T4 at the high potential of the main circuit.
It is connected to the gate terminal of H4. The primary winding of the transformer is connected to the pulse generation circuit of the control circuit 20. That is, the pulse transformers PT1 and PT2
The primary winding of which is connected to the α controller 2A for performing normal phase angle control, also, the primary of the pulse transformer PT3, PT4
The winding is connected to the common terminal C of the switches SA3 and SA4. The switch terminal 1 of the switch SA3, SA4, through
It is connected to the α control unit 2A that supplies the normal phase control signals 2m and 2m, and the switching terminal 2 of the switch has α = 0 °.
Phase control signal 2n with a fixed phase angle, that to supply 2n alpha =
0 control unit 2B is connected. Switch SA3, SA4
Is selected on the switching terminal 1 side, the thyristor TH3
The gate signal of TH4 is provided as an output signal of the control circuit 2A, and these thyristors TH3 and TH4 perform the same phase control as that shown in FIG. That is, the thyristor converter 10 operates as a single-phase full-wave bridge type. When the switches SA3 and SA4 are selected on the switching terminal 2 side, the operation waveform as shown in FIG. 2 is obtained. In this case, at the time when the anode potentials of the thyristors TH3 and TH4 become positive, that is, at times (c) and (a) in FIG. 2, a gate signal from the control circuit 2B is applied to the gate terminal of each thyristor, and TH3 and TH4 are energized at a phase angle of 0 °, and perform the same operation as a diode.
As a result, the DC output voltage shown in FIG. 2C is obtained, and the thyristor converter 10 operates as a single-phase mixed-bridge type.

Embodiment 4 FIG. FIG. 6 is a circuit diagram showing a thyristor conversion device according to Embodiment 4 of the present invention, in which the control circuit units 2A and 2B of Embodiment 3 are embodied. In FIG. 6, the control circuit 20 includes an α control unit 2A,
α = 0 control unit 2B, switches SA3 and SA4, and pulse transformers PT1 to PT4. TR is a control transformer for obtaining a control voltage having the same phase u and opposite phase v as the main circuit voltage. In the α control unit 2A, R1 and C1 are a resistor and a capacitor, and the phase voltage Ec1 lags by about 90 ° from the control voltage of the same phase u or the phase voltage lags by about 90 ° from the control voltage of the opposite phase v. A phase delay circuit for obtaining the voltage Ec2 is formed. Es is a control voltage for phase control, and is input to comparators CP1 and CP2 for comparison with phase voltages Ec1 and Ec2. R2 and C2 are resistors and capacitors, and form a differentiating circuit for differentiating the outputs of the comparators CP1 and CP2.
Further, a resistor R3, a capacitor C3, a diode DS1,
DS2 and transistors TR1 and TR2 form a pulse amplifier that amplifies the output of the differentiating circuit. An α control unit 2A that obtains a normal phase control signal from these circuits is configured. Next, in the α = 0 control unit 2B, the firing thyristor TS4 is provided between the control voltage v of the opposite phase and the switching terminal 2 of the switch SA4, and the firing thyristor TS3 switches with the control voltage u of the same phase. It is provided between the terminal 2 of the device SA3. R4 and C4 are resistors and capacitors that obtain a phase lead current for the control voltage and form a lead circuit that provides a gate current to the gate of the firing thyristor with this current.

FIG. 7 is a waveform chart showing the operation of the circuit of FIG. FIG. 7C is a waveform showing the relationship between the control voltage ES and the phase voltage Ec1. These voltages are applied to the comparator CP
1 and the output of the comparator CP1 is:
The one shown in FIG. 7D is obtained. When the output of the comparator CP1 is input to a differentiating circuit including the resistor R2 and the capacitor C2, a differential waveform shown in FIG. 7E is output. This differential signal is input to a pulse amplifier including a resistor R3, a capacitor C3, a diode DS1, and a transistor TR1, and a pulse current (pulse amplified waveform) shown in FIG. 7F is applied to the primary winding of the pulse transformer PT1. Can be When the switch SA4 is selected on the switching terminal 1 side, this pulse current is also supplied to the pulse transformer PT4. As a result, the gate current of FIG. 7B is applied to the gate terminals of the thyristors TH1 and TH4. Further, the gate current of FIG. 7B whose phase is shifted by 180 ° is applied to the gate terminals of the thyristors TH2 and TH3 by the same circuit operation. As a result, the thyristor converter 10 operates as a single-phase full-wave bridge. When the switch SA4 is selected on the switching terminal 2 side in FIG. 6, the resistor R4 is connected to the gate terminal of the firing thyristor TS4.
AC power supply A from the advance circuit consisting of
The gate current ig4 shown in FIG. 7 (g), which is advanced by about 90 ° from the voltage of the C voltage, flows.
Are conducted, and the primary winding of the pulse transformer PT4 is
A pulse current shown in (h) is applied. As a result, the thyristor TH4 is energized at a phase angle of 0 °, and performs the same operation as the diode. Further, the gate current of FIG. 7 (h) whose phase is shifted by 180 ° is applied to the gate terminal of the thyristor TH3 by the same circuit operation. As a result, the thyristor converter 10 operates as a single-phase mixed-bridge type.

Embodiment 5 FIG. FIG. 8 is a circuit diagram showing a configuration of a thyristor conversion device according to Embodiment 5 of the present invention. In FIG. 8, DA is a diode provided between the DC output terminals P and N of the main circuit. When the switch SA is on the switch terminal 1 side, the diode DA is disconnected from the circuit,
The thyristor converter 10 operates as a single-phase full-wave bridge. When the switch SA is on the switching terminal 2 side, the diode DA is connected to the DC output circuit, and the thyristor converter 10 operates as a single-phase mixed bridge type.

[0024]

According to the first aspect of the present invention, in the single-phase full-wave rectifier bridge thyristor converter, each of the two thyristors in one of the series circuits is provided. Since the gate terminal can be connected to the phase control terminal, which is the output of the control circuit, or connected to the anode of each thyristor via a series circuit of a resistor and a diode, it can be selectively switched by a switch. With the configuration, there is an effect that the function of either the single-phase full-wave bridge system or the single-phase mixed bridge system can be easily selected and used.

According to the second aspect, a thyristor to be selected for operation by the same switch as described above is connected to the DC output terminal P and the AC input terminals U and V, or is connected to the DC output terminal N and the DC output terminal N. Since the range is broadened to those connected to the AC input terminals U and V, there is an effect that the degree of freedom for the hardware configuration can be increased in addition to the effect of the first invention.

According to the third aspect, the switching device provides
Normal phase control signal of control circuit or ignition phase angle of 0 °
Is switched and supplied to the gate terminal of the thyristor, so that the conventional main circuit configuration can be used as it is.

According to the fourth aspect of the present invention, since the gate signal switch is included in the control circuit, the main circuit configuration has the effect that the conventional one can be used as it is, and the operation in the control circuit is not limited. The components or circuit elements connected to the switch are composed of versatile components such as a control transformer, a phase delay circuit consisting of a resistor and a capacitor, a differentiation circuit, a lead circuit, a small signal thyristor, a transistor, and the pulse transformer can be shared. Therefore, there is an effect that the manufacture of this device becomes easy.

According to the fifth aspect, in the single-phase full-wave rectifier bridge thyristor conversion circuit, the switching device
Since it is possible to selectively switch between connecting and not connecting the diode to the DC output terminal, there is an effect that a device with a small number of components can be manufactured.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a thyristor conversion device according to Embodiment 1 of the present invention.

FIG. 2 is a waveform chart for explaining the operation of the device of FIG.

FIG. 3 is a circuit diagram showing a thyristor conversion device according to Embodiment 2 of the present invention.

FIG. 4 is a diagram for explaining the operation of the device in FIG. 3;

FIG. 5 is a circuit diagram of a thyristor conversion device according to Embodiment 3 of the present invention.

FIG. 6 is a circuit diagram of a thyristor conversion device according to Embodiment 4 of the present invention.

FIG. 7 is a waveform chart for explaining the operation of the device of FIG. 6;

FIG. 8 is a circuit diagram of a thyristor conversion device according to Embodiment 5 of the present invention.

FIG. 9 is a circuit diagram showing a conventional thyristor conversion device.

FIG. 10 is a circuit diagram showing a conventional thyristor conversion device.

11 is a circuit diagram showing a control circuit of the device shown in FIG.

FIG. 12 is a waveform chart for explaining the operation of the device of FIG. 9;

FIG. 13 is a waveform chart for explaining the operation of the device of FIG. 10;

FIG. 14 is a diagram for explaining the operation of the apparatus shown in FIGS. 9 and 10;

[Explanation of symbols]

 Reference Signs List 10 thyristor conversion device 20 control circuit TH1 to TH4 thyristor D1, D2, DA diode AC AC power supply LF load SA, SA2 to 4 switch RA2 to 4 resistor PT1 to 4 pulse transformer

Claims (5)

(57) [Claims] A single-phase full-wave rectifier bridge-type thyristor conversion circuit having two sets of thyristor series circuits, wherein a control circuit is connected to each gate terminal of two thyristors of one of the series circuits. A thyristor conversion device provided with a switch for switching between connection of a phase control terminal, which is an output terminal of the thyristor, and connection of an anode of each thyristor via a series circuit of a resistor and a diode. 2. A circuit having a single-phase full-wave rectifier bridge-type thyristor conversion circuit having two sets of thyristor series circuits, wherein one of the DC output terminals P and N is connected to both AC input terminals U and V. A switch is provided to switch between connecting the phase control terminal, which is the output terminal of the control circuit, to each gate terminal of the two thyristors in between, or connecting the anode of each of the thyristors through a series circuit of a resistor and a diode. A thyristor converter. 3. A single-phase full-wave rectifier bridge type thyristor conversion circuit having two sets of thyristor series circuits, wherein the gate terminal or the DC output terminal of each of the two thyristors of any one series circuit is provided. A normal phase control signal, which is an output of the control circuit, is supplied to each gate terminal of two thyristors between one of them and both AC input terminals U and V, or a phase having a firing phase angle of 0 °. A thyristor conversion device comprising a switch for switching whether to supply a control signal. 4. A circuit for outputting a normal phase control signal,
A control transformer for obtaining a control voltage having the same phase and an opposite phase as the main circuit voltage, a phase delay circuit for obtaining a phase voltage Ec having a phase delay of about 90 ° from the control voltage having the same phase,
c, a comparator for comparing the control voltage Es for phase control, a differentiating circuit for differentiating the output of the comparator, and a pulse amplifier for amplifying the output of the differentiating circuit. A circuit for outputting a phase control signal to be controlled by an ignition thyristor provided between an output terminal of a control voltage having a phase opposite to that of the main circuit voltage and a terminal of the switch, and a control voltage having a phase opposite to that of the main circuit voltage. 4. The thyristor conversion device according to claim 3, wherein said thyristor conversion device comprises a lead circuit for obtaining a phase lead current and supplying a gate current of said firing thyristor. 5. A circuit having a single-phase full-wave rectifier bridge type thyristor conversion circuit having two sets of thyristor series circuits A and B, wherein a diode is connected or not connected between both DC output terminals P and N. A thyristor conversion device comprising a switching device for selectively switching.