JPH0767319A - Gate-power supplying circuit - Google Patents

Abstract

PURPOSE:To omit a high-withstand-voltage insulated converter by moving snubber energy stored in a first capacitor into a second capacitor through a reactor, and utilizing the energy when the switching element provided in a main circuit is turned OFF. CONSTITUTION:A free wheeling diode 4 and a DC balance resistor 5 are connected in parallel a self-extinguishing-type element (GTO) 1 constituting a power converter. One end of a first capacitor 6 is connected to the anode of the GTO 1, and the other end is connected to the anode of a diode 7. One end of a reactor 8 is connected to the anode of the first diode 7, and the other end is connected to the cathode of the GTO 1. One end of a second capacitor 9 and the cathode of the first diode 7 are connected. The other end of the second capacitor 9 is connected to the cathode of the GTO 1. A gate driving circuit 10 receives the supply of energy stored in the second capacitor 9 at the time of the switching operation of the GTO 1. Thus, the gate driving circuit 10 is operated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention utilizes switching operation of a self-arc-extinguishing element or the like to supply power from a main circuit to a gate drive circuit of the self-arc-extinguishing element or a control / protection circuit of a main circuit section. The present invention relates to a gate power supply circuit that supplies power and has a function as a snubber circuit for a self-extinguishing element.

[0002]

2. Description of the Related Art By applying a self-arc-extinguishing element to a power converter such as an inverter device, harmonics on the power supply side and load side are suppressed, the power supply power factor is improved, and the device is downsized, etc. The advantages of Until now, we have not been able to obtain self-extinguishing elements that can withstand high voltage and large current, but recently GT
Since it has become possible to manufacture a self-arc-extinguishing element suitable for high-voltage, high-current applications such as O, application of the self-arc-extinguishing element to the field of high power has become active.

One of the problems in applying a self-arc-extinguishing element such as a GTO to a high power field is a snubber problem. When the self-extinguishing element turns off the current, the element may be damaged unless it is kept below a certain value determined by the voltage rise rate of the element. Especially in the case of GTO, which is the most widely used in the high power field,
It is necessary to strictly limit the rate of voltage rise. Even if the element is not damaged, if the voltage increase rate at turn-off is large, the switching loss of the element increases, and the temperature of the switching element rises, resulting in a decrease in reliability. A snubber circuit is connected in parallel with the switching element to suppress the voltage rise rate of the element.

In many cases, an RDC snubber in which a snubber diode and a snubber capacitor are connected in series and a resistor is connected in parallel to the snubber diode is used as the snubber circuit. When the switching element turns off, the current that was flowing in the element is rectified once in the snubber circuit, and when the snubber capacitor is charged and the element voltage rises sufficiently, it is rectified in the other switching element. . The electric charge charged in the snubber capacitor is discharged through the snubber resistor while the GTO is turned on again, and the snubber energy is consumed by the snubber resistor.

The snubber power consumed by the snubber resistor is about several KW for one GTO, depending on the type of GTO and the switching frequency, and accounts for a considerable portion of the total loss of the power converter. Since the snubber capacitor occupies a large volume, the snubber circuit becomes an obstacle to downsizing the power converter.

Another problem in applying self-turn-off devices such as GTOs to high voltage applications is that of gate drive power supplies. In particular, in the case of GTO which is a switching element mainly used in the field of high power, it becomes a big problem. This is because the GTO is a current control element and has a small current amplification factor during turn-off, so a very large current, which is a fraction of the main circuit current, must be passed through the GTO gate. Further, even when the GTO is turned on, it is necessary to keep the current flowing in the gate in order to reduce the conduction loss. Therefore, the power consumption of the GTO gate drive circuit is
100 per GTO, depending on the GTO product type
It reaches more than w.

Since the GTO gate drive circuit is directly connected to the GTO cathode and gate to be driven, it is electrically placed at the same potential as the GTO cathode to be driven. When the GTOs are connected in series, the gate drive circuits of the respective GTOs are placed at different potentials, so the power supplies of the respective gate drive circuits must also have different potentials. That is, the power supplies of the gate driving circuit must be insulated from each other for each GTO.

For that purpose, an example of a GTO gate drive circuit which has been conventionally used is shown in FIG. FIG. 9 shows one GTO constituting the power conversion circuit and a circuit associated therewith.

In FIG. 9, GTO 1 is a main switching element, and diode 4 is a freewheeling diode, which serves as a main circuit current path in a regenerative mode. The resistor 5 is a DC balance resistor, and has a function of balancing the DC sharing voltage of each of the GTOs connected in series so as not to be affected by slight variations in the characteristics of the GTOs. The diode 2, the capacitor 3 and the resistor 17 form a snubber circuit of the GTO 1 to suppress the rate of voltage rise of the GTO 1 and suppress the loss of the GTO at turn-off.

The gate of GTO1 is a gate drive circuit 10
Driven by. The ON / OFF signal of the gate is transmitted as an optical signal by the optical fiber 11 and converted into an electric signal by an optical receiving module (not shown) in the gate drive circuit 10. Since an optical signal is used, isolation for each GTO 1 is automatically achieved for the gate on / off signal. The gate drive circuit 10 is powered by the isolation transformer 13
The high frequency power supplied from the high frequency AC power supply 14 via the rectifier 12 is rectified by the rectifier 12 to obtain DC power. The high frequency AC power supply 14 is placed in a low potential part and is commonly used by each GTO 1, and the potential difference between the GTOs 1 is insulated by the insulation transformer 14 facing each GTO 1.

[0011]

However, there is a big problem in applying the prior art to a converter in which a large number of GTOs are connected in series and the DC bus voltage exceeds several tens of KV. That is, in order to send high frequency power from the low potential portion through the insulation transformer 13, a high voltage of several tens KV can be insulated.
This is because a large number of insulation transformers 13 having extremely high withstand voltage are required. Such an insulating transformer 13 not only requires a large space, but also becomes extremely expensive.

Further, the snubber circuit has a large loss, and the snubber capacitor requires a large space. For the above reasons, in terms of space and cost, the prior art has a problem in connecting a large number of GTOs in series and applying them to high voltage applications.

Therefore, an object of the present invention is to eliminate the insulating transformer and obtain the electric power supplied to the gate drive circuit of the self-arc-extinguishing element from the snubber energy of the main circuit. To provide.

[0014]

In order to achieve the above object, a gate power supply device according to claim (1) of the present invention is connected in parallel with a switching element constituting a power conversion circuit. A series circuit including a first capacitor, a first diode and a second capacitor, a connection point between the first capacitor and the first diode, the second capacitor and the switching element. It further comprises a reactor connected between a connection point of the switching element and and the connection point thereof, and supplies the energy stored in the second capacitor to a gate drive circuit of the switching element or the like.

The gate power supply circuit according to claim (2) of the present invention includes a first capacitor and a first diode which are connected in parallel to a switching element which constitutes a power conversion device. And a series circuit including a second capacitor,
A series circuit of a reactor and a second diode connected between a connection point between the first capacitor and the first diode and a connection point between the second capacitor and the switching element; And a third capacitor connected in parallel to the second capacitor, and supplying the energy stored in the third capacitor to a gate drive circuit of the switching element or the like. To do.

Further, a gate power supply circuit according to claim (3) of the present invention includes a first capacitor and a first capacitor which are connected in parallel to a switching element which constitutes a power conversion device.
Between a series circuit composed of a diode and a second capacitor, and a connection point between the first capacitor and the first diode and a connection point between the second capacitor and the switching element. Connected reactor and second dio-
And a series circuit with a battery, and the energy stored in the second capacitor is supplied to a gate drive circuit of the switching element and the like.

Furthermore, a game according to claim (4) of the present invention.
The power supply circuit includes a series circuit including a first capacitor, a first diode, and a second capacitor that are connected in parallel to a switching element that constitutes the power conversion device, and the first capacitor. A reactor connected between a connection point between the second capacitor and the first diode and a connection point between the second capacitor and the switching element, and a resistor connected in parallel with the second capacitor. And supplying energy stored in the second capacitor to a gate drive circuit of the switching element and the like. The gate power supply circuit according to claim (5) of the present invention comprises a first capacitor, a first diode, and a second capacitor which are connected in parallel to a switching element which constitutes a power conversion device. A series circuit including a capacitor, a reactor connected between a connection point between the first capacitor and the first diode, and a connection point between the second capacitor and the switching element, A series circuit of a resistor and a semiconductor switching element connected in parallel to the second capacitor is provided, and energy stored in the second capacitor is supplied to a gate drive circuit of the switching element, In addition, the semiconductor switch is turned on / off according to the voltage of the second capacitor.

[0018]

In the invention according to claim (1), the current flowing through the switching element when the switching element is turned off is a snubber circuit including a first capacitor, a first diode and a second capacitor. The snubber energy stored in the first capacitor while the switching element is off is converted to the second capacitor via the reactor while the switching element voltage increase rate is suppressed. Then, the energy is supplied to the gate drive circuit or the like connected in parallel to the second capacitor.

In the invention according to claim (2), the current flowing through the switching element when the switching element is turned off is a snubber circuit including a first capacitor, a first diode and a second capacitor. The snubber energy stored in the first capacitor while the switching element is off is converted to the second capacitor via the reactor while the switching element voltage increase rate is suppressed. Then, the energy is supplied to the gate drive circuit and the like connected in parallel to the third capacitor via the third capacitor.

In the invention according to claim (3), the current flowing through the switching element when the switching element is turned off is a snubber circuit including a first capacitor, a first diode and a second capacitor. The snubber energy stored in the first capacitor while the switching element is off is converted to the second capacitor via the reactor while the switching element voltage increase rate is suppressed. Then, the energy is supplied to the gate drive circuit or the like connected in parallel to the second capacitor, but the second diode connected in series to the reactor causes the current of the reactor while the switching element is on. The vibration of can be eliminated.

In the invention according to claim (4), the current flowing through the switching element when the switching element is turned off is a snubber circuit including a first capacitor, a first diode and a second capacitor. The snubber energy stored in the first capacitor while the switching element is off is converted to the second capacitor via the reactor while the switching element voltage increase rate is suppressed. Then, energy is supplied to the gate drive circuit and the like connected in parallel to the second capacitor, but most of the snubber energy is consumed by the resistor connected in parallel to the second capacitor, so gate drive is performed. The power supply voltage of the gate drive circuit or the like can be kept at a constant value regardless of the power consumption of the circuit or the like.

In the invention according to claim (5), the current flowing through the switching element when the switching element is turned off is a snubber circuit including a first capacitor, a first diode and a second capacitor. The snubber energy stored in the first capacitor while the switching element is off is converted to the second capacitor via the reactor while the switching element voltage increase rate is suppressed. And supplies energy to a gate drive circuit or the like connected in parallel to the second capacitor, but the second capacitor is connected by the resistor connected in parallel to the second capacitor via the second switching element. Because snubber energy is consumed according to the voltage of
The power supply voltage of the gate drive circuit and the like can be kept constant regardless of the operating conditions of the main circuit and some fluctuations of the gate drive circuit.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing an embodiment of the present invention, in which reference numeral 1 is a self-extinguishing element (hereinafter referred to as GTO1) which constitutes a power conversion device. -Connect the battery 4 and the DC balance resistor 5 in parallel with the GTO 1. One end of the first capacitor 6 is GT
It is connected to the node of O1 and the other end is connected to the node of the first diode 7. One end of the reactor 8 is connected to the anode of the first diode 7, and the other end is connected to the cathode of the GTO 1.
Connect to the computer. One end of the second capacitor 9 is connected to the cathode of the first diode 7, and the other end of the second capacitor 9 is connected to the cathode of the GTO 1. Gate drive circuit 1
0 operates by receiving the energy stored in the second capacitor 9 during the switching operation of the GTO 1.

The operation of the gate power supply circuit of FIG. 1 configured as described above will be described with reference to the piezoelectric current waveform shown in FIG. While the GTO1 is off, the first capacitor 6 is charged through the first diode 7 and the second capacitor 9 to the DC sharing voltage of the GTO1.

At time point A in FIG. 2, the GTO 1 starts turning on. From time A, the voltage VAK between the anode and cathode of GTO1 decreases, and along with this, the charge of the first capacitor 6 is discharged through the path of the first capacitor 6 → GTO1 → reactor 8 → first capacitor 6, The voltage VC6 of the first capacitor 6 begins to drop. First capacitor 6
Is discharged, the voltage of the first capacitor 6 becomes zero, and the current IL8 of the reactor 8 reaches the maximum value. Then, the current of the reactor 8 charges the first capacitor 6 in the opposite direction, and the time point B is reached. At time B, the voltage of the first capacitor 6 becomes equal to the voltage of the second capacitor 9, the first diode 7 starts to conduct, and the current ID7 of the first diode 7 rises. When the first diode 7 is turned on, the current of the reactor 8 is divided into the second capacitor 9 and the first capacitor 6. Second in this state
The current ratio between the capacitor 9 and the first capacitor 6 is equal to the capacitance ratio. The capacity of the second capacitor 9 is
In order to suppress the fluctuation of the supply voltage to the gate drive circuit 10, the value is set to be much larger than that of the first capacitor 6, so that most of the current of the reactor 8 flows into the second capacitor 9. That is, after time B, almost all the energy that the reactor 8 has flows into the second capacitor 9. At time point C, the current ID7 of the first diode 7 becomes zero.

At time point C, the first capacitor 6 is charged in the reverse direction. This energy is gradually consumed in the form of conduction loss of the GTO 1 while being vibratively exchanged with the reactor 8 after the time point C, and the GTO 1 is turned off at the time point D and the first capacitor is turned off. Vibration continues until 6 is recharged. The period from the time point D to the time point E is the turn-off period of the GTO1, and the current flowing in the GTO1 is commutated to the path of the first capacitor 6 → the first diode 7 → the second capacitor 9 and The capacitor 6 of 1 is charged. During this period, the voltage rise rate of the GTO 1 is suppressed by the first capacitor 6, so it can be seen that the first capacitor 6 functions as a snubber capacitor.

As described above, in the embodiment of FIG. 1, the first capacitor 6 acts as a snubber capacitor, and the snubber energy stored in the first capacitor 6 is passed through the reactor 8 to the second capacitor 9 Then, it is used as a power source for the gate drive circuit 10.

As described above, in the embodiment shown in FIG.
, The first diode 7, and the second capacitor 9 operate as a snubber circuit of the GTO 1. On the other hand, the voltage of the second capacitor 9 has a ripple component that fluctuates according to the switching operation of the GTO 1. Therefore, it is necessary to use a large-capacity capacitor for the second capacitor 9 in order to suppress the ripple. However, if a large-capacity capacitor is used as the second capacitor 9, the operation of this snubber circuit will be hindered. An electrolytic capacitor generally used as a large-capacity capacitor has a relatively large parasitic inductance component inside the capacitor. When an electrolytic capacitor is used as the second capacitor 9, the parasitic inductance hinders the commutation from the GTO 1 to the shunaba circuit when the GTO 1 is turned off, and a spike-like jump appears in the voltage of the GTO 1.
Such a voltage spike causes the GTO 1 to be destroyed.

FIG. 3 is a block diagram showing a second embodiment of the present invention made in consideration of this point. In the embodiment of FIG. 3, a third capacitor 16 is connected in parallel with the second capacitor 9 of the embodiment shown in FIG. 1, and a capacitor having a small parasitic capacitance but a small parasitic inductance is used as the second capacitor 9. A large-capacity capacitor is used as the third capacitor 16 even if the parasitic inductance is large. In this way, the series circuit of the first capacitor 6, the first diode 7, and the second capacitor 9 does not hinder the operation of the snubber circuit of the GTO 1 and is large. Since there is the third capacitor 16 having a capacitance, the ripple amount of the power supply voltage of the gate drive circuit can be suppressed to be small.

As shown in FIG. 4, the operation of the embodiment of FIG. 3 is almost the same as that of the embodiment of FIG. 1, but the embodiment of FIG. 1 is regarded as an ideal capacitor having no internal inductance component. In contrast to the second capacitor 9 described above, in the embodiment shown in FIG.
Capacitor 16 is connected. Therefore, the voltage VC9 of the second capacitor 9 oscillates with the switching operation of the GTO 1. Reactor 8 from time B to time C
Is a period during which the first capacitor 6, the second capacitor 9 and the third capacitor 16 are being charged by the current of 1), and during this period, between the second capacitor 9 and the third capacitor 16, This is because charges are exchanged via the parasitic inductance component inside the capacitor 1 of 3. This vibration continues for a while after time C,
The vibration energy is lost due to the resistance component inside the third capacitor 16, and eventually becomes a steady state. In the period after time D, the oscillation of the voltage VC9 of the second capacitor 9 appears for the same reason.

If the oscillating voltage of the second capacitor 9 is too large, the operation as a snubber circuit will be hindered.
As can be seen from FIG. 4, the vibration can be suppressed to the extent that there is no particular problem even with the component constants that are normally obtained. Also,
It is necessary to pay attention not only to selection of component constants but also to mounting. It is desirable that the first capacitor 6, the first diode 7, and the second capacitor 9 which operate as the snubber circuit of the GTO 1 are arranged close to the GTO 1 and the wiring is made as short as possible. This is to prevent the inductance due to the wiring from entering the snubber circuit. The third capacitor 16 and the reactor 8 do not participate in the operation as the snubber circuit so much, and thus such precautions are not necessary.

As can be seen from FIG. 2, in the first embodiment of the present invention, the voltage of the first capacitor 6 and the current of the reactor 8 are between the time point C and the time point D, that is, while the GTO 1 is on. Is vibrating. Depending on the application, this vibration may be a problem. FIG. 5 is a block diagram showing a third embodiment of the present invention made in consideration of this point.
In the embodiment of FIG. 5, a second diode 15 having the illustrated polarity is connected in series to the reactor 8 of the embodiment shown in FIG.

The operation of the third embodiment shown in FIG. 5 will be described below with reference to FIG. From time A to time C in FIG. 6, the same operation as in the embodiment of FIG. 3 is performed. After time C, the operation differs due to the action of the second diode 15. That is, although the first capacitor 6 is reversely charged, even if this electric charge tries to discharge through the reactor 8, the discharge is blocked by the second diode 15 which is serially connected to the reactor 8. Therefore, the reverse charge of the first capacitor 6 is maintained as it is until the time D when the GTO 1 starts to turn off again, and the oscillating current does not flow. After the time point D, when the current flowing to the GTO 1 flows through the first capacitor 6, the first diode 7 and the second capacitor 9 to recharge the first capacitor 6, the reverse charging charge Will flow into the second capacitor 9.

As described above, the snubber power of GTO1 is G
Depending on the type of TO1, it will be several KW per GTO. In the above description, all of the snubber power is explained to be consumed by the gate drive circuit, but actually, as described above, the power consumption of the gate drive circuit is 100%.
It is about W. In recent GTO elements, the value of the snubber capacitor tends to decrease, and the snubber power tends to decrease accordingly, but the snubber power is still much higher than the power consumption of the gate drive circuit. . Therefore, it is necessary to consume the surplus power that cannot be consumed by the gate drive circuit in some form.

This point is taken into consideration in the fourth embodiment of the present invention shown in FIG. In the embodiment of FIG. 7, the resistor 23 is connected in parallel with the second capacitor 9. Second
Most of the snubber power supplied to the capacitor 9 is consumed by the resistor 23, and the remaining power is used by the gate drive circuit 10. Even if the power consumption of the gate drive circuit 10 fluctuates to some extent due to fluctuations in the constants on the gate drive circuit side, the power consumption of the resistor 23 is hardly affected, and thus the power supply of the gate drive circuit 10 The voltage hardly changes. However, when the operating conditions on the main circuit side such as the fluctuation of the DC bus voltage and the fluctuation of the switching frequency change, the snubber power supplied to the second capacitor 9 also changes. The fifth embodiment of the present invention shown in FIG. 8 is an embodiment for suppressing the power supply voltage of the gate drive circuit 10 to a constant value even in such a case.

In the fifth embodiment of the present invention shown in FIG. 8, a semiconductor switch 24 is connected in series with a resistor 23. When the voltage of the second capacitor 9 is too high, the semiconductor switch 24 is turned on, and when the voltage of the second capacitor 9 is too low, the semiconductor switch 24 is turned off.
With such a configuration, the voltage of the second capacitor 9 can take a substantially constant value regardless of the operating conditions on the main circuit side and the power consumption of the gate drive circuit. Although a transistor is shown as the semiconductor switch 24 in FIG. 8, the present invention does not limit the semiconductor switch 24 to a transistor, and other semiconductor switches such as GTO and MOSFET may be used.

In the above description, an example in which a GTO is used as a switching block constituting a power conversion device has been described, but the present invention is not limited to the case where the switching element is a GTO, and is a self-extinguishing type. It may be an element.

Further, in the above description, since the switching element is the GTO, 10 is the gate drive circuit. However, the present invention can be applied to the case where the switching element is a transistor etc. -Use a drive circuit, etc.

Furthermore, although the name of the present invention is a gate drive circuit, the present invention can be applied to the case where the switching element is a transistor or the like as described above, and the power supply circuit of the present invention is a gate drive circuit only. Since it can supply power to control / protection circuits of other high-voltage parts as well, the power supply target of the gate power supply circuit is a circuit that controls switching elements such as transistors or the like. Control and protection circuits for other high-voltage parts are also included.

[0040]

As described above, according to the gate power supply circuit according to the first aspect of the present invention, the first capacitor is provided when the switching element placed in the main circuit is turned off. The snubber energy stored in is transferred to the second capacitor via the reactor while the switching element is on, and the energy stored in the second capacitor is used. The high withstand voltage insulation transformer is unnecessary, and the power conversion circuit composed of self-extinguishing elements can be downsized and the cost can be reduced.

According to the gate power supply circuit of the second aspect of the present invention, in addition to the effect of the invention of the first aspect, the ripple of the power supply voltage of the gate drive circuit is obtained. Minutes can be suppressed.

Further, according to the gate power supply circuit of the present invention in accordance with claim (3), in addition to the effect of the invention according to claim (1), a reactor constituting the gate power supply circuit. It is possible to suppress the oscillating current flowing in

Furthermore, according to the gate power supply circuit of the present invention according to claim (4), in addition to the effect of the invention according to claim (1), the power consumption of the gate drive circuit is reduced. The power supply voltage of the gate drive circuit can be kept constant regardless of fluctuations.

Further, according to the gate power supply circuit of the present invention according to claim (5), in addition to the effect of the invention according to claim (1), the operating conditions of the main circuit and the gate drive are provided. The power supply voltage of the gate drive circuit can be kept constant regardless of fluctuations in power consumption of the circuit.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a gate power supply circuit of the present invention.

FIG. 2 is an operation waveform diagram for explaining the operation of the gate power supply circuit shown in FIG.

FIG. 3 is a configuration diagram showing a second embodiment of a gate power supply circuit of the present invention.

FIG. 4 is an operation waveform diagram for explaining the operation of the gate power supply circuit shown in FIG.

FIG. 5 is a configuration diagram showing a third embodiment of a gate power supply circuit of the present invention.

FIG. 6 is an operation waveform diagram for explaining the operation of the gate power supply circuit shown in FIG.

FIG. 7 is a configuration diagram showing a fourth embodiment of a gate power supply circuit of the present invention.

FIG. 8 is a configuration diagram showing a fifth embodiment of a gate power supply circuit of the present invention.

FIG. 9 is a configuration diagram of a conventional gate power supply circuit.

[Explanation of symbols]

 1 ... Self-extinguishing element, 2 ... Snubber diode, 3 ... Snubber capacitor, 4 ... Freewheeling diode, 5 ... DC balance resistance, 6 ... First capacitor, 7 ...... First diode, 8 ...... Reactor, 9 ・ ・ ・ Second capacitor, 10 ・ ・ ・ Gate drive circuit, 11 ・ ・ ・ Optical fiber, 12 ・ ・ ・ Rectifier, 13 ・ ・ ・ Insulation transformer, 14 ...... High frequency AC power supply, 15 ...... Second diode, 16 ...... Third capacitor, 17 ...... Snubber resistance, 23 ...... Resistance, 24 ...... Switching element,

Claims (5)

[Claims] 1. A first capacitor and a first capacitor which are connected in parallel to a switching element constituting a power conversion device.
A series circuit consisting of a diode and a second capacitor in that order, a connection point between the first capacitor and the first diode, and a connection point between the second capacitor and the switching element. A gate power supply circuit, comprising a reactor connected to the second capacitor, and supplying the energy stored in the second capacitor to a gate drive circuit of the switching element. 2. A first capacitor and a first capacitor which are connected in parallel to a switching element which constitutes a power conversion device.
A series circuit consisting of a diode and a second capacitor in that order, a connection point between the first capacitor and the first diode, and a connection point between the second capacitor and the switching element. And a third capacitor connected in parallel to the second capacitor, and the energy stored in the third capacitor is applied to a gate drive circuit of the switching element or the like. A gate power supply circuit characterized by supplying power. 3. A first capacitor and a first capacitor which are connected in parallel to a switching element which constitutes the power conversion device.
A series circuit consisting of a diode and a second capacitor in that order, a connection point between the first capacitor and the first diode, and a connection point between the second capacitor and the switching element. And the second dio connected to the
And a series circuit with a gate, and supplies the energy stored in the second capacitor to a gate drive circuit of the switching element and the like. 4. A first capacitor and a first capacitor which are connected in parallel to a switching element constituting the power conversion device.
Between a series circuit composed of a diode and a second capacitor, and a connection point between the first capacitor and the first diode and a connection point between the second capacitor and the switching element. A reactor connected to the second capacitor, and a resistor connected in parallel to the second capacitor, and supplying the energy stored in the second capacitor to a gate drive circuit of the switching element or the like. Gate power supply circuit characterized by: 5. A first capacitor and a first capacitor which are connected in parallel to a switching element which constitutes the power conversion device.
Between a series circuit composed of a diode and a second capacitor, and a connection point between the first capacitor and the first diode and a connection point between the second capacitor and the switching element. A series circuit including a connected reactor, a resistor connected in parallel to the second capacitor, and a semiconductor switching element is provided, and the energy stored in the second capacitor is transferred to the gate of the switching element.
A gate power supply circuit for supplying power to a gate drive circuit and the like, and turning on / off the semiconductor switch according to the voltage of the second capacitor.