JPH08320348A - Simulation circuit of self-arc-extinguishing device with communication diode - Google Patents

Abstract

PURPOSE: To improve the characteristic of the simulation circuit, of a self-are- extinguishing device with a commutation diode, which is used in an analog simulator. CONSTITUTION: A simulation circuit 20 is constituted of an N-MOSFET 21 with a built-in diode, of an amplifier 22, of a comparator 23, of an inverter element 24 and of an OR element 25. The source of the MOSFET 21 is used as a reference voltage. When a drain-to-source voltage is positive, the MOSFET 21 is turned on and off on the basis of an on-off instruction to be input to the OR element 25. When the drain-to-source voltage is negative, a positive bias is given to the gate of the MOSFET 21, and the MOSFET 21 is set to a conduction state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an analog simulator for analyzing the behavior of a power system to which, for example, a semiconductor power conversion circuit is connected as a load device, and more particularly to a self-commutation diode-equipped self-conversion diode used in a semiconductor power conversion circuit. The present invention relates to a simulation circuit of an arc extinguishing type device.

[0002]

2. Description of the Related Art When a semiconductor power conversion circuit is incorporated in an analog simulator, it is necessary to idealize and simulate a power semiconductor device used in the semiconductor power conversion circuit. For example, the forward voltage drop of a power semiconductor device is made as small as possible, the operation of this power semiconductor device is simulated by a circuit using standardized electronic components on the market, and the operating voltage of this simulation circuit is set to a few. It is desired that the voltage can be incorporated into an analog simulator as a voltage of several tens of volts.

FIG. 2 is a circuit diagram showing a conventional example of a simulation circuit of this type of self-turn-off device with a commutation diode. In FIG. 2, 1 is a variable voltage DC power source, 2 is a simulation circuit of a self-arc-extinguishing device with a commutation diode (hereinafter simply referred to as simulation circuit 2), and 3 is a load. The simulation circuit 2 includes an operational amplifier 4, a transistor 5, a diode 6, a positive side DC power supply 7 of the operational amplifier 4, and a negative side DC power supply 8 of the operational amplifier 4.

The operation of the simulation circuit of FIG. 2 will be described below.
When there is a potential difference between the DC power supply 1 and the load 3 in the direction in which a current flows from C to E between the terminals C and E in FIG. 2, the output of the operational amplifier 4 becomes positive and the diode 6 becomes non-conductive, and the terminal C- There is no electrical connection between E. In this state, when an ON / OFF command is input from the outside to the B terminal shown in the figure, the transistor 5 becomes conductive based on this ON command, and the feedback from the terminal E causes the operational amplifier 4 to operate as a voltage follower. Direct current power supply 1 is established between terminals C and E.
Is applied to the load 3 as it is. At this time, the operating state of the self-turn-off device is simulated.

Further, when there is a potential difference between the DC power supply 1 and the load 3 in the direction in which a current flows from E to C between the terminals C and E in FIG. 2, the diode 6 conducts, and the operational amplifier 4 is fed back from the terminal E. Acts as a voltage follower,
The voltage of the DC power supply 1 is applied to the load 3 as it is. At this time, the operating state of the commutation diode is simulated.

[0006]

According to the above-mentioned conventional simulation circuit of the self-arc-extinguishing device with a commutation diode, due to the slew rate and frequency characteristics of the operational amplifier 4, a response delay occurs when the simulation circuit is operated at a high speed. There was a problem that occurred. Further, when the instantaneous value of the variable-voltage DC power supply 1 exceeds the voltage of the positive-side DC power supply 7 or the negative-side DC power supply 8, the simulation circuit may operate abnormally.

An object of the present invention is to provide a simulation circuit for a self-turn-off device with a commutation diode that solves the above problems.

[0008]

The present invention relates to a simulation circuit of a self-arc-extinguishing device with a commutation diode used in an analog simulator. The first invention is an N-channel MOS type electric field effect incorporating a diode. The potential of the transistor and the source of the field effect transistor is used as a reference potential, and when the value obtained by amplifying the voltage between the drain and the source is negative with respect to the reference potential, an ON signal is given to the gate of the field effect transistor to amplify And a control circuit that gives an on / off signal to the gate of the field effect transistor based on an on / off command to the self-arc-extinguishing device that is input from the outside. Prepare

According to a second aspect of the present invention, in the simulation circuit, an N-channel MOS field effect transistor having a built-in diode, a current transformer connected to a drain terminal or a source terminal of the field effect transistor, and a current transformer of the current transformer. When a current is flowing from the source terminal to the drain terminal of the field effect transistor, an ON signal is given to the gate of the field effect transistor, and when the current of the current transformer is not flowing in the direction, an external signal is applied from the outside. A control circuit for applying an on / off signal to the gate of the field effect transistor based on an on / off command to the self-extinguishing device input.

[0010]

According to the present invention, by positively biasing the gate-source voltage V _GS of an N-channel MOS type field effect transistor having a built-in diode, the current of the field effect transistor flows in the same direction in both directions, and a normal diode is used. The action is to reduce the forward voltage drop.

Further, the field effect transistor can reduce a forward voltage drop, has a high-speed switching characteristic, and has a high withstand voltage characteristic.

[0012]

1 is a circuit diagram of a simulation circuit of a self-turn-off device with a commutation diode showing a first embodiment of the present invention. In FIG. 1, 1 is a variable voltage direct current power source,
Reference numeral 20 is a simulation circuit 20 of a self-turn-off device with a commutation diode (hereinafter, simply referred to as simulation circuit 20), and 3 is a load.

The simulation circuit 20 has a built-in diode N
Channel MOS field effect transistor 21 (hereinafter,
(Referred to simply as field effect transistor 21) and amplifier 2
2, a comparator 23, an inverter element 24, an OR element 25, a positive side DC power source 26 of the amplifier 22 and the comparator 23, a negative side DC power source 27 of the amplifier 22 and the comparator 23, an inverter element 24 not shown, It is composed of a power source for the element 25.

The operation of the simulation circuit 20 will be described below. When there is a potential difference between the DC power supply 1 and the load 3 in the direction in which a current flows from C to E between the terminals C and E in FIG. 1, assuming that the source terminal of the field effect transistor 21 is the reference potential, the output of the amplifier 22 is the reference potential. It becomes positive with respect to the potential, the output of the comparator 23 becomes high level, and the inverter element 2
The output of 4 is low level, the output of the OR element 25 is also low level, and the terminals C and E are not conductive. In this state, when an ON / OFF command is input to the B terminal shown in the figure from the outside, the output of the OR element 25 becomes high level based on this ON command, and the gate-source voltage V _GS of the field effect transistor 21 is changed. Since the bias is positively applied, the field effect transistor 21 becomes conductive. At this time, the operating state of the self-turn-off device is simulated.

Further, when there is a potential difference between the DC power supply 1 and the load 3 in the direction in which a current flows from E to C between the terminals C and E in FIG. 1, the output of the amplifier 22 becomes negative with respect to the reference potential, and the comparator The output of 23 becomes low level,
The output of the inverter element 24 becomes high level, the output of the OR element 25 also becomes high level, and the terminals C and E are in a conductive state. At this time, the operating state of the commutation diode is simulated.

FIG. 3 is a circuit configuration diagram of a simulation circuit of a self-turn-off device with a commutation diode showing a second embodiment of the present invention. Components having the same functions as those in FIG. are doing. That is, in FIG. 3, the field effect transistor 2 is included in the simulation circuit 30 (hereinafter, simply referred to as simulation circuit 30) of the self-arc-extinguishing device with a commutation diode.
Current transformer 31 connected to the source terminal of No. 1 and current transformer 31
Resistor 32 connected in parallel with the secondary winding of
A comparator 23, an inverter element 24, an OR element 25, an amplifier 33 and a positive side DC power source 26 of the comparator 23, an amplifier 33 and a negative side DC power source 27 of the comparator 23, an inverter element 24 and an OR element not shown. 25 power supplies.

The operation of the simulation circuit 30 will be described below. When the electric potential of the DC power supply 1 is lower than the electric potential of the load 3, a current flows from E to C between the terminals C and E in FIG. 3, and at this time, the current shown in FIG. When a voltage is generated and input to the amplifier 33, the resistance 3
The output of the amplifier 33 that amplifies the voltage across both ends of 2 becomes a negative potential, the output of the comparator 23 becomes low level, the output of the inverter element 24 becomes high level, the output of the OR element 25 also becomes high level, and the terminal CE There is continuity between the two. At this time, the operating state of the commutation diode is simulated.

When the potential of the DC power source 1 is higher than the potential of the load 3, the current in the primary winding of the current transformer 31 becomes zero. At this time, for example, a slight offset voltage (several millivolts or less) is applied to the input of the amplifier 33. ) Is provided so that the output of the amplifier 33 becomes a positive potential, and as a result, the comparator 2
3 becomes high level, the output of the inverter element 24 becomes low level, the output of the OR element 25 also becomes low level, and the terminals CE of FIG.
In this state, when an ON / OFF command is input to the B terminal shown in the figure from the outside, the output of the OR element 25 becomes high level based on this ON command, and the gate-source voltage V _GS of the field effect transistor 21 is changed. Since the bias is positively applied, the field effect transistor 21 becomes conductive. At this time, the operating state of the self-turn-off device is simulated.

For example, six sets of the above-mentioned simulation circuits 20 or 30 are used, and C is connected to the collector of the transistor, E is the emitter of the transistor, and B is the base terminal of the transistor, and three-phase bridge connection is made. As a result, the main circuit of the three-phase inverter circuit with the commutation diode can be simulated.

[0020]

According to the present invention, the N-channel MOS field effect transistor having a built-in diode can reduce the forward voltage drop, has a high-speed switching characteristic, and has a high withstand voltage characteristic. When the operating voltage of the analog simulator can be set in a wide range and further the forward voltage drop is desired to be reduced, the field effect transistors may be connected in parallel, and the circuit current can be easily increased.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of a simulation circuit of a self-turn-off device with a commutation diode showing a first embodiment of the present invention.

FIG. 2 is a circuit configuration diagram of a simulation circuit of a self-turn-off device with a commutation diode showing a conventional example.

FIG. 3 is a circuit configuration diagram of a simulation circuit of a self-turn-off device with a commutation diode showing a second embodiment of the present invention.

[Explanation of symbols]

1 DC power supply 2 Simulation circuit 3 Load 4 Operational amplifier 5 Transistor 6 Diode 7 Positive side DC power supply 8 Negative side DC power supply 20 Simulation circuit of self-turn-off device with commutation diode 21 N-channel MOS field effect transistor with built-in diode 22 Amplifier 23 Comparator 24 Inverter element 25 OR element 26 Positive side DC power source 27 Negative side DC power source 30 Simulated circuit of self-extinguishing type device with commutation diode 31 Current transformer 32 Resistance 33 Amplifier

Claims (2)

[Claims] 1. A simulation circuit of a self-arc-extinguishing device with a commutation diode used in an analog simulator, wherein an N-channel MOS type field effect transistor having a built-in diode and a source potential of the field effect transistor is used as a reference potential. When the amplified value of the drain-source voltage is negative with respect to the reference potential, an ON signal is given to the gate of the field effect transistor, and when the amplified value is positive with respect to the reference potential, externally A self-arc-extinguishing diode with a commutation diode, comprising: a control circuit for applying an ON / OFF signal to the gate of the field effect transistor based on an ON / OFF command input to the self-arc-extinguishing device. Device simulation circuit. 2. A simulation circuit of a self-extinguishing device with a commutation diode used in an analog simulator, wherein an N-channel MOS field effect transistor containing a diode and a drain terminal or a source terminal of the field effect transistor are connected. And a current of the current transformer flowing from the source terminal to the drain terminal of the field effect transistor, an ON signal is applied to the gate of the field effect transistor, Control circuit that gives an ON / OFF signal to the gate of the field effect transistor based on an ON / OFF command to the self-arc-extinguishing device that is input from the outside when the current does not flow in the direction. Circuit of self-extinguishing type device with commutation diode.