CN201126461Y - Circuit Structure of High Power Pulse Thyristor Valve for Resonance - Google Patents

Abstract

A high-power pulse thyristor valve circuit structure for resonance, belonging to the field of power electronic devices, including a thyristor valve overcurrent test basic circuit, characterized in that a trigger circuit is added to the overcurrent test basic circuit, and the trigger circuit is in When the thyristor valve is locked, a continuous trigger pulse is generated, which is added to the gate of each thyristor; an RC damping circuit is added; the high-power pulse thyristor valve is composed of two valve sections connected in series, and each valve section is 12 or 16 Thyristor poles are connected in series. The circuit structure realizes the voltage control function of the thyristor valve due to the adoption of a special trigger control method and RC damping circuit. Up to 45kA pulse current, and has flexible multi-working mode.

Description

Circuit Structure of High Power Pulse Thyristor Valve for Resonance

technical field

The utility model belongs to the circuit field of power electronic devices, in particular to a circuit structure of a high-power pulse thyristor valve for resonance.

Background technique

High-voltage series valves based on high-power power electronic components, or thyristor valves, and their auxiliary circuits, are the core components of flexible AC transmission (FACTS) and high-voltage direct current transmission (HVDC). A new type of semiconductor device developed on the basis of silicon rectifier elements. Its shape can be divided into two types: spiral shape and flat plate shape. Regardless of the shape, it is the tube core that determines its strength. It is a four-layer structure of P ₁ N ₁ P ₂ N ₂ arranged by P-type silicon and N-type silicon. There are three PN junctions J ₁ , J ₂ , J ₃ , the anode is drawn from the _P1 area of the _J1 junction, the control electrode is drawn from the _P2 area of the _J2 junction, and the cathode is drawn from the _N2 area of the _J3 junction. Due to its own fragility, the operation reliability is still relatively low, which greatly limits the development of FACTS and HVDC, so from the perspective of circuit structure to improve the operation reliability of high-voltage series valves and their survival in various power system states Capability has become a key issue related to whether FACTS and HVDC can be widely used in power systems.

The overcurrent test device is a device used to test the overcurrent or fault current of high-voltage gate valves of FACTS and HVDC equipment. It can test the valve's ability to withstand fault current, voltage and related thermal effects. The special circuit structure of the high-power pulse thyristor valve is used in this device, which makes this overcurrent test device different from the traditional test device. The previous test circuit is difficult to guarantee the reliability of the operation of the high-voltage series valve. Withstand the impact of high voltage and high pulse current of tens of thousand amperes or more.

Existing high-voltage valves are often used in the field of direct current transmission and flexible alternating current transmission, but they can only withstand steady-state current, maintain high impedance when blocking, and withstand voltage. However, there are no relevant reports in domestic and foreign literature on high-voltage thyristor valves that meet the working conditions such as blocking voltage, high pulse current, etc.

Contents of the invention

The technical problem to be solved by the utility model is that, for the circuit structure of the high-power pulse thyristor in the prior art, it is difficult to make the thyristor meet the requirements of various switching electromagnetic transient strengths, and it is difficult to withstand high fault current, voltage and related thermal effect capabilities , in order to overcome these shortcomings, it is necessary to redesign the circuit structure of the thyristor valve to improve the tolerance of the thyristor valve. The purpose of this utility model is to provide a high-power pulse thyristor valve circuit structure for resonance. The circuit is characterized in that a trigger circuit is added to the basic circuit of the overcurrent test, and the trigger circuit generates continuous trigger pulses to be added to the gates of each thyristor when the thyristor valve is locked; an RC damping loop is added; in the circuit The high-power pulse thyristor valve is composed of two valve sections in series, and each valve section is composed of 12 or 16 thyristor poles connected in series.

The reason why the special trigger control and trigger circuit is used in the circuit structure of the high-power pulse thyristor valve for resonance is to use the continuous trigger pulse generated when the valve is locked to be added to the gates of each thyristor to promote the redistribution of the carrier concentration inside the thyristor. , and to a certain extent stimulate the positive feedback process of the two equivalent PNP transistors, thereby greatly weakening the barrier voltage of the thyristor J2 junction, so the thyristor can keep the terminal voltage very low although there is no current. The RC damping circuit refers to the addition of a protection device Va for absorbing overshoot voltage. A specially designed RC damping circuit is added to meet the requirements of high current change rate turn-on and high turn-off voltage overshoot. The specially added protection device Va is used to absorb the overshoot voltage that may be caused by resonance.

The mechanical structure of the high-power pulse thyristor valve for resonance is composed of two valve sections connected in series. This is based on the voltage and current intensity requirements of the thyristor valve, selecting a suitable thyristor element, and then considering the dynamic and static characteristics of the thyristor and considering stray Parameters, optimize the configuration of the damping absorption circuit and DC voltage equalizing circuit of the thyristor valve, so that the thyristor valve can meet the requirements of various switching electromagnetic transient strengths, and at the same time make the voltage distribution on the thyristor level relatively uniform.

The beneficial effect of the utility model is that the circuit structure realizes the voltage control function of the thyristor valve due to the adoption of a special trigger control mode and a special RC damping circuit, and the potential distribution on the thyristor stage under high voltage is uniform; it not only isolates and controls High voltage, but also can pass through the pulse high current up to 45kA, and has flexible multi-working mode. In previous engineering applications, there was no high-voltage thyristor valve with such functions.

The working voltage between the valve terminals of the high-power pulse thyristor valve is up to 110kV; the current is 45kA, the frequency is 150Hz-350Hz, and the resonant current can be turned off at any zero-crossing point, and then you can choose to withstand voltage mode or not to withstand voltage mode according to requirements; it has flexible Multiple working modes.

Description of drawings

Fig. 1a is a spiral shape structure diagram in an existing thyristor;

Fig. 1b is a planar outline structure diagram in an existing thyristor;

Figure 1c is a schematic diagram of the connection symbols of each electrode of the thyristor

Figure 1d is a schematic diagram of the internal structure of the thyristor;

Fig. 2 is the pulse thyristor series mechanical structure composed of two valve sections;

Figure 3a is a schematic diagram of a thyristor valve overcurrent test device;

Figure 3b is an RC damping circuit with protection device Va added.

Detailed ways

Referring to Fig. 1a and Fig. 1b, it shows the shape and structure of the thyristor in the prior art. 1 in the figure represents the thyristor, and there are two kinds of shapes, which are respectively helical shape 1 and flat plate shape 1'. Referring to Fig. 1c, it shows the thyristor Electrode connection symbol diagram, K represents the cathode of the thyristor, A represents the anode, and G represents the control grid. Referring to Figure 1d, it shows the relationship between the layers in the internal structure diagram of the thyristor, from the bottom anode to the top cathode, There are four layers of P ₁ , N ₁ , P ₂ , and N ₂ structures, and three PN junctions J ₁ , J ₂ , and J ₃ are formed. Referring to Fig. 2, it shows the mechanical structure of a high-power pulse thyristor valve 2 connected in series by two valve sections. The connection structure of this valve can make the thyristor withstand higher pulse power. Referring to Fig. 3a, it shows the schematic diagram of the thyristor valve overcurrent test device. The figure shows the trigger circuit 3.1 and the RC damping circuit 3.2. Referring to Fig. 3b, this figure shows the RC damping circuit 3.2 after the protection device Va is added. In this circuit Among them, the introduction of Va increases the function of absorbing overshoot voltage.

Claims (3)

1. a resonance is with high power pulse thyristor valve circuit structure, comprise thyristor valve overcurrent test basic circuit, it is characterized in that, in described overcurrent test basic circuit, trigger circuit have been increased, these trigger circuit are to produce continuous trigger pulse when the thyristor valve locking, are added to the gate pole of each thyristor; Increased the RC damping circuit; Described high power pulse thyristor valve is to be composed in series by two valve sections, and each valve section is that 12 or 16 thyristor utmost points are in series.

2. according to the described resonance of claim 1 high power pulse thyristor valve circuit structure, it is characterized in that, in the described RC damping circuit, increased a protective device Va who absorbs overshoot voltage.

3. according to the described resonance of claim 1 high power pulse thyristor valve circuit structure, it is characterized in that described resonance is to be composed in series by two valve sections with the physical construction of high power pulse thyristor valve.

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