CN111579981B - A circuit and method for simulating the on-off voltage of a converter valve - Google Patents

Abstract

The invention discloses a circuit and a method for simulating the turn-on and turn-off voltage of a converter valve, wherein the circuit comprises: the circuit comprises a thyristor, an inductor, a switch component, a first capacitor and a second capacitor, wherein the anode of the thyristor is externally connected with the anode of a direct-current power supply; the cathode of the thyristor is connected with one end of an inductor, and the other end of the inductor is respectively connected with one end of a switch component and one end of a second capacitor; the other end of the switch assembly is connected with one end of the first capacitor, and the switch assembly is used for controlling the first capacitor to be connected to or quit the circuit for simulating the on-off voltage of the converter valve; the other end of the first capacitor and the other end of the second capacitor are connected with the negative electrode of the direct-current power supply; the two ends of the second capacitor are externally connected with a valve test article to be tested. The invention can meet the output requirement that the on-voltage is different from the off-voltage when the simulation converter valve engineering actually operates, has simple circuit structure and lower cost, and is beneficial to the research on the on-off characteristics of the valve and the performance test and the optimized model selection of each component in the valve.

Description

A circuit and method for simulating the on-off voltage of a converter valve

technical field

The invention relates to the field of operation test of an ultra-high pressure converter valve, in particular to a circuit and a method for simulating the on-off voltage of a converter valve.

Background technique

The core components of modern high-power power electronic devices are unidirectional and bidirectional UHV converter valves. UHV converter valves utilize the switching characteristics of internal thyristors to complete their functions as "high voltage switches" and become the most widely used power electronics. device. The technical indicators and technical level of the UHV converter valve largely determine the technical indicators and level of the DC project, so it is necessary to test the electrical performance of the UHV converter valve.

In order to verify the operating performance of the UHV converter valve, it is necessary to simulate the voltage waveform in actual engineering, and for the test of the on-off characteristics of the UHV converter valve, the focus is to construct the voltage when the valve is turned on or off. At present, the main test method is the synthetic full-condition test method, which can be further subdivided into the combined test method of oscillatory boost and DC current source, the combined test method of direct boost and DC current source, and the combined test method of oscillatory boost and AC current source . The turn-on voltage of the UHV converter valve in the actual operation of the project is different from the turn-off voltage, but the test device used in the existing synthetic full-condition test method can only output the forward and reverse voltages of the same magnitude, which cannot meet the requirements of special conditions. The turn-on voltage of the high-voltage converter valve is different from the output requirements of the turn-off voltage, that is, it is impossible to simulate the voltage of the UHV converter valve when it is turned on or off, and thus it is impossible to determine the turn-on and turn-off characteristics of the valve test product under engineering operating conditions. carry out testing.

SUMMARY OF THE INVENTION

Therefore, the technical problem to be solved by the present invention is to overcome the fact that the test device in the prior art cannot simulate the voltage of the UHV converter valve when it is turned on or off, and thus cannot be used to turn on and off the valve test product under engineering operating conditions. Therefore, a circuit and method for simulating the on-off voltage of a converter valve are provided.

To achieve the above object, the present invention provides the following technical solutions:

In a first aspect, an embodiment of the present invention provides a circuit for simulating the on-off voltage of a converter valve, including: a thyristor, an inductor, a switch component, a first capacitor and a second capacitor, wherein the anode of the thyristor is connected to an external DC power source. positive pole; the cathode of the thyristor is connected to one end of the inductor, and the other end of the inductor is connected to one end of the switch component and one end of the second capacitor respectively; the other end of the switch component is connected to the first One end of a capacitor is connected, and the switch component is used to control the first capacitor to access or exit the circuit that simulates the on-off voltage of the commutator valve; the other end of the first capacitor and the second capacitor The other end is connected to the negative pole of the DC power supply; the two ends of the second capacitor are outside the test valve sample.

In one embodiment, the switch assembly includes a first switch assembly and a second switch assembly, the first switch assembly is connected in series with the second switch assembly.

In one embodiment, the first switch assembly and the second switch assembly each include: one or more press-fit units, the press-fit units include: an IGBT device and a diode in anti-parallel with the IGBT device, and The on-current directions of the IGBT devices in the first switch assembly and the IGBT devices in the second switch assembly are opposite.

In one embodiment, when there are multiple press-fitting units, each of the press-fitting units is connected in series.

In a second aspect, an embodiment of the present invention provides a method for simulating the on-off voltage of a converter valve, which is applied to the circuit for simulating the on-off voltage of a converter valve described in the first aspect of the embodiment of the present invention, including: The valve test product is connected to the circuit that simulates the on-off voltage of the converter valve; the thyristor is triggered to turn on, and the switch assembly is controlled to connect the first capacitor to the circuit that simulates the on-off voltage of the converter valve, When the external DC power supply charges the first capacitor and the second capacitor to the preset turn-on voltage of the valve test product to be tested, the thyristor is triggered to turn off; the turn-on process of the valve test product to be tested: control The action of the switch assembly triggers the opening of the valve sample to be tested, so that the first capacitor and the second capacitor discharge to the valve sample to be tested at the same time; the shut-off process of the valve sample to be tested: through The switch component controls the time when the first capacitor exits the circuit that simulates the on-off voltage of the converter valve, so that the valve test product to be tested reversely charges the second capacitor to the valve to be tested When the preset cut-off voltage of the test product is reached, the test product of the valve to be tested is triggered to be turned off.

In one embodiment, the method further includes: after the valve sample to be tested is turned off, controlling the switch component to restore the first capacitor and the second capacitor to an initial voltage level.

The technical scheme of the present invention has the following advantages:

The circuit for simulating the on-off voltage of a converter valve provided by the present invention utilizes a thyristor, an inductor, a switch component, a first capacitor and a second capacitor to construct a circuit for simulating the on-off voltage of the converter valve, and controls the sequence of the switch components by constructing a circuit for simulating the on-off voltage of the converter valve , and then control the time when the first capacitor is connected to or exits the circuit that simulates the turn-on and turn-off voltage of the converter valve, so as to simulate the turn-on or turn-off voltage of the converter valve, and the turn-on voltage is different from the turn-off voltage, thereby satisfying the commutation valve. The turn-on voltage of the valve is different from the output requirement of the turn-off voltage. The circuit for simulating the turn-on and turn-off voltage of the converter valve is simple in structure and low in cost, and can simulate the turn-on and turn-off process of the actual operation of the valve project under test conditions, and the turn-on and turn-off voltages during the project operation are generated at both ends of the converter valve. , and can meet the turn-on and turn-off voltage requirements of the rectifier side and the inverter side. It is of great significance to the research of the valve turn-off and turn-off characteristics, as well as the performance test and optimization of the various components in the valve.

The method for simulating the on-off voltage of the converter valve provided by the present invention controls the sequence of the switch components by connecting the test valve sample to be tested to the circuit for simulating the on-off voltage of the converter valve, and then controls the first capacitor to be connected or withdrawn. Simulate the time when the converter valve turns on and off the voltage circuit, so as to simulate the turn-on or turn-off voltage of the converter valve, and the turn-on voltage is different from the turn-off voltage. This further satisfies the output requirement that the on-voltage of the converter valve is different from the off-voltage. The circuit for simulating the on-off voltage of the converter valve used in the test power generation method is simple in structure and low in cost, and can simulate the on-off process of the actual operation of the valve engineering under the test conditions, and generate engineering operation at both ends of the converter valve. It can meet the on-off voltage requirements of the rectifier side and the inverter side, which is of great significance to the research of the valve on-off characteristics, the performance test and the optimization of the valve components.

Description of drawings

In order to illustrate the specific embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the specific embodiments or the prior art. Obviously, the accompanying drawings in the following description The drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

FIG. 1 is a circuit diagram of a specific example of a circuit for simulating an on-off voltage of a converter valve in an embodiment of the present invention;

2 is a schematic diagram of a multi-stage series structure of a press-fitting unit of a circuit simulating the on-off voltage of a converter valve in an embodiment of the present invention;

3 is a circuit diagram of another specific example of a circuit for simulating an on-off voltage of a converter valve in an embodiment of the present invention;

FIG. 4 is a power control sequence diagram of a method for simulating an on-off voltage of a converter valve according to an embodiment of the present invention.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first", "second", and "third" are used for descriptive purposes only and should not be construed to indicate or imply relative importance.

In the description of the present invention, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense, unless otherwise expressly specified and limited, for example, it may be a fixed connection or a detachable connection connection, or integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two components, which can be a wireless connection or a wired connection connect. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

An embodiment of the present invention provides a circuit for simulating the on-off voltage of a converter valve, as shown in FIG. 1 , including: a thyristor T1, an inductor L, a switch component K, a first capacitor C1 and a second capacitor C2, wherein the thyristor T1 The anode of the thyristor is connected to the positive pole of the DC power supply DC; the cathode of the thyristor T1 is connected to one end of the inductance L, and the other end of the inductance L is connected to one end of the switch component K and one end of the second capacitor C2 respectively; the other end of the switch component K is connected to the first One end of the capacitor C1 is connected, and the switch component K is used to control the first capacitor C1 to access or exit the circuit that simulates the on-off voltage of the converter valve; the other end of the first capacitor C1 and the other end of the second capacitor C2 are connected to the DC power supply DC The negative pole of the second capacitor C2 is connected to the test valve sample P outside the two ends of the second capacitor C2.

The circuit for simulating the on-off voltage of a converter valve provided by the present invention utilizes a thyristor, an inductor, a switch component, a first capacitor and a second capacitor to construct a circuit for simulating the on-off voltage of the converter valve, and controls the sequence of the switch components by constructing a circuit for simulating the on-off voltage of the converter valve , and then control the time when the first capacitor is connected to or exits the circuit that simulates the turn-on and turn-off voltage of the converter valve, so as to simulate the turn-on or turn-off voltage of the converter valve, and the turn-on voltage is different from the turn-off voltage, thereby satisfying the commutation valve. The turn-on voltage of the valve is different from the output requirement of the turn-off voltage. The circuit for simulating the turn-on and turn-off voltage of the converter valve is simple in structure and low in cost, and can simulate the turn-on and turn-off process of the actual operation of the valve project under test conditions, and the turn-on and turn-off voltages during the project operation are generated at both ends of the converter valve. , and can meet the turn-on and turn-off voltage requirements of the rectifier side and the inverter side. It is of great significance to the research of the valve turn-off and turn-off characteristics, as well as the performance test and optimization of the various components in the valve.

In the embodiment of the present invention, as shown in FIG. 2 , the switch assembly K includes: a first switch assembly K1 and a second switch assembly K2, and the first switch assembly K1 is connected in series with the second switch assembly K2. The first switch assembly K1 and the second switch assembly K2 both include: a plurality of press-fitting units M, each press-fitting unit M is composed of an IGBT device and a diode connected in anti-parallel with the IGBT device, and the IGBT in the first switch assembly K1 The on-current direction of the device is opposite to that of the IGBT device in the second switch assembly K2. When there are a plurality of press-fitting units M, the respective press-fitting units M are connected in series. When the valve test product P to be tested requires different levels of turn-on or turn-off voltages, the number of stages of the press-fitting unit M can be increased or decreased. By adjusting the series number of IGBT and diode parallel units to meet the test requirements of different voltage levels, it should be noted that the embodiment shown in FIG. 2 is a press-fit unit in the first switch assembly K1 and the second switch assembly K2 Each of M is an exemplary illustration for an example. In practical applications, there may be only one press-fitting unit M in the first switch assembly K1 and the second switch assembly K2, and the present invention is not limited to this.

In the embodiment of the present invention, as shown in FIG. 3 , the first switch assembly K1 and the second switch assembly K2 each include a press-fitting unit M as an example for description. The circuit for simulating the on-off voltage of the converter valve includes: a thyristor T1, an inductor L, a first pressing unit M1, a second pressing unit M2, a first capacitor C1 and a second capacitor C2, wherein the anode of the thyristor T1 The positive pole of the external DC power supply DC; the cathode of the thyristor T1 is connected to one end of the inductance L, and the other end of the inductance L is respectively connected to one end of the first press-fitting unit M1 and one end of the second capacitor C2; the other end of the first press-fitting unit M1 is connected. One end is connected to one end of the second press-fitting unit M2, and the other end of the second press-fitting unit M2 is connected to one end of the first capacitor C1; the other end of the first capacitor C1 and the other end of the second capacitor C2 are connected to the DC power supply DC. The negative pole is connected; the two ends of the second capacitor C2 receive the test valve sample P.

The first press-fitting unit M1 includes a first IGBT device G1 and a diode D1 connected in anti-parallel with the first IGBT device G1, and the second press-fitting unit M2 includes: a second IGBT device G2 and an anti-parallel connection with the second IGBT device G2 diode D2, and the on-current directions of the first IGBT device G1 in the first pressing unit M1 and the second IGBT device G2 in the second pressing unit M2 are opposite. The first press-fitting unit M1 is connected in series with the second press-fitting unit M2, and is used to control the first capacitor C1 to be connected or withdrawn from the circuit that simulates the on-off voltage of the converter valve.

An embodiment of the present invention also provides a method for simulating the on-off voltage of a converter valve, which is applied to the circuit for simulating the on-off voltage of a converter valve as shown in FIG. 3 , and includes the following sequence steps:

Step S1: Connect the valve sample P to be tested to a circuit that simulates the on-off voltage of the converter valve.

Step S2: Trigger the thyristor T1 to turn on, control the second IGBT device G2 to turn on, connect the first capacitor C1 to the circuit that simulates the on-off voltage of the commutator valve, and connect the external DC power supply DC to charge the first capacitor C1 and the second capacitor C2 When the preset turn-on voltage of the valve test product P to be tested is reached, the thyristor T1 and the second IGBT device G2 are triggered to turn off.

Step S3: the opening process of the valve test product P to be tested: controlling the first IGBT device G1 to be turned on, triggering the opening of the valve test product P to be tested, so that the first capacitor C1 and the second capacitor C2 are simultaneously connected to the valve to be tested. Test sample P discharges;

Step S4: the shut-off process of the valve test product P to be tested: by controlling the turn-off time of the first IGBT device G1, the first capacitor C1 is withdrawn from the circuit that simulates the on-off voltage of the converter valve, so that the valve test product P to be tested is turned off. When the second capacitor C2 is reversely charged to the preset cutoff voltage of the valve test sample P to be tested, the valve test sample P to be tested is triggered to be turned off.

In the embodiment of the present invention, by connecting both ends of the valve sample P to be tested with both ends of the second capacitor C2, the valve sample P to be tested is connected to a circuit that simulates the on-off voltage of the converter valve.

Assume that the open voltage of the valve test product P to be tested is U1, and the cut-off voltage is U2. The circuit operation sequence is shown in FIG. 4 , and the output voltage of the power supply includes the voltage of the first capacitor C1 in the positive direction and the voltage of the second capacitor C2 in the negative direction. The pre-charging process starts at time _t0 : the thyristor T1 and the second IGBT device G2 are turned on, and the first capacitor C1 is controlled to be connected to the circuit that simulates the on-off voltage of the commutator valve. C2 jointly determines the charging time. The external DC power supply DC charges the first capacitor C1 and the second capacitor C2 to the preset turn-on voltage U1 of the valve test product P to be tested. After the charging is completed, the thyristor T1 and the second IGBT device G2 are turned off. In other embodiments, according to the turn-on voltage level of the valve test product P to be tested, DC power sources DC of different voltage levels are selected.

At time _t1 , the valve sample P to be tested and the first IGBT device G1 are turned on at the same time, and the first capacitor C1 and the second capacitor C2 are controlled to discharge the valve sample P to be tested at the same time. The charging voltage is U1, which is exactly the voltage at the time of opening of the valve sample P to be tested, which is equivalent to the opening process of the valve sample P to be tested.

After the valve test product P to be tested and the first IGBT device G1 are turned on, since most of the components in the valve test product P to be tested are inductive loads, the first capacitor C1 and the second capacitor C2 resonately discharge to the inductive load. When the current of the test valve test product P reaches the peak value, the capacitance voltage of the first capacitor C1 and the second capacitor C2 drops to zero, and then the current in the test valve test product P to be tested gradually decreases, and the first capacitor C1 and the second capacitor C1 and the second capacitor C2 begins to receive reverse charging of the valve sample P to be tested.

Control the turn-off time of the first IGBT device G1 so that the first capacitor C1 exits the circuit, and the valve test product P to be tested continues to charge the second capacitor C2, so that the valve test product P to be tested reversely charges the second capacitor C2 to The preset cut-off voltage of the valve test product P to be tested, when the test product current of the test valve test product P to be tested gradually decreases to zero, the test product P of the test valve to be tested is turned off at time _t2 , and the voltage of the second capacitor C2 is just The shut-off voltage of the valve test product P to be tested is equivalent to the shut-off process of the valve test product P to be tested.

Due to the turn-on process, the first capacitor C1 and the second capacitor C2 simultaneously discharge the valve test product P to be tested, and the voltage of the valve test product is U1 when the valve test product is turned on, and during the turn-off process, the voltage of the second capacitor C2 is just the turn-off of the test product. voltage U2. C1+C2≠C2, so turn-on voltage U1≠turn-off voltage U2, thus satisfying the output requirement that the turn-on voltage of the converter valve is different from the turn-off voltage.

In the embodiment of the present invention, after the valve test product P to be tested is turned off, the first capacitor C1 and the second The voltage on capacitor C2 returns to the initial voltage level in preparation for the next cycle.

The method for simulating the on-off voltage of the converter valve provided by the present invention utilizes the constructed circuit for simulating the on-off voltage of the converter valve, and controls the sequence of the switch components to control the first capacitor to connect or exit the analog converter valve on-off. The time when the circuit of the voltage is turned off. During the turn-on process, the first capacitor and the second capacitor discharge simultaneously to the valve sample to be tested, that is, the voltage of the valve sample when it is turned on, and during the turn-off process, the voltage of the second capacitor is just the sample. The turn-on voltage of the converter valve is simulated, and the turn-on voltage is different from the turn-off voltage, thus satisfying the output requirement that the turn-on voltage of the converter valve is different from the turn-off voltage. The circuit for simulating the on-off voltage of the converter valve used in the test power generation method is simple in structure and low in cost, and can simulate the on-off process of the actual operation of the valve engineering under the test conditions, and generate engineering operation at both ends of the converter valve. It can meet the on-off voltage requirements of the rectifier side and the inverter side, which is of great significance to the research of the valve on-off characteristics, the performance test and the optimization of the valve components.

Obviously, the above-mentioned embodiments are only examples for clear description, and are not intended to limit the implementation manner. For those of ordinary skill in the art, changes or modifications in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. However, the obvious changes or changes derived from this are still within the protection scope of the present invention.

Claims (4)

1. A circuit for simulating the on-off voltage of a converter valve, characterized in that it comprises: a thyristor, an inductor, a switch component, a first capacitor and a second capacitor, wherein, The anode of the thyristor is connected to the anode of the DC power supply; The cathode of the thyristor is connected to one end of the inductor, and the other end of the inductor is respectively connected to one end of the switch component and one end of the second capacitor; The other end of the switch component is connected to one end of the first capacitor, and the switch component is used to control the first capacitor to be connected to or withdrawn from the circuit that simulates the on-off voltage of the converter valve; The other end of the first capacitor and the other end of the second capacitor are connected to the negative electrode of the DC power supply; Both ends of the second capacitor receive the test valve sample; The switch assembly includes: a first switch assembly and a second switch assembly, the first switch assembly is connected in series with the second switch assembly; The first switch assembly and the second switch assembly each include: one or more press-fit units, the press-fit units include: an IGBT device and a diode in anti-parallel with the IGBT device, and the first switch assembly The on-current directions of the middle IGBT device and the IGBT device in the second switch assembly are opposite. 2 . The circuit for simulating the on-off voltage of a converter valve according to claim 1 , wherein when there are multiple press-fitting units, each of the press-fitting units is connected in series. 3 . 3. A method for simulating the on-off voltage of a converter valve, applied to the circuit for simulating the on-off voltage of a converter valve as described in any one of claims 1-2, characterized in that, comprising: Connect the valve test product to be tested to the circuit that simulates the on-off voltage of the converter valve; Trigger the thyristor to turn on, control the switch component to connect the first capacitor to the circuit that simulates the on-off voltage of the commutator valve, and charge the first capacitor and the second capacitor to the voltage of the external DC power supply. Trigger the thyristor to turn off when the preset turn-on voltage of the valve test product to be tested is activated; The opening process of the valve sample to be tested: controlling the action of the switch assembly to trigger the opening of the valve sample to be tested, so that the first capacitor and the second capacitor discharge simultaneously to the valve sample to be tested; The shut-off process of the valve sample to be tested: the time when the first capacitor exits the circuit that simulates the on-off voltage of the converter valve is controlled by the switch component, so that the valve sample to be tested can be connected to all the samples. When the second capacitor is reversely charged to the preset cutoff voltage of the valve test sample to be tested, the valve test sample to be tested is triggered to be turned off. 4 . The method for simulating the on-off voltage of a converter valve according to claim 3 , further comprising: after the valve sample to be tested is turned off, by controlling the switch assembly to switch the first The capacitor and the second capacitor are restored to the original voltage level.

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