CN204497176U - Without electric arc type supercharging bridge-type high-tension electricity circuit breaker - Google Patents

Abstract

The utility model provides a non-arc type supercharged bridge high-voltage power circuit breaker, which is composed of a mechanical switch K, a supercharged bridge switch, a controller P, input and output monitoring instruments V1 and V2, and the supercharged bridge switch is composed of a diode D1, D2, D3, and D4 are the bridge arms, and the non-contact switches (T1T2...Tn, n≥2) in series are used as the bridge. The positive pole of D1 and the negative pole of D2 are connected with the input terminal of the K contact to the high-voltage input (IR) D3 positive pole and D4 negative pole are connected to the high-voltage output (OUT) terminal with the K contact outlet, and the control pole of the switch group is connected to P. When the switch is opened, the K contact is broken first and the switch group is broken last. When the switch is closed, the switch group is connected first. The K contact is connected later, thereby eliminating the condition for the circuit breaker to generate an arc, and replacing the current high-voltage circuit breaker with this circuit breaker, the problem of preventing and controlling the arc of the high-voltage circuit breaker will no longer exist.

Description

Arc-free booster bridge high-voltage power circuit breaker

technical field

The utility model mainly relates to the field of high-voltage electric power, in particular to a high-voltage circuit breaker with a voltage level above 3KV.

Background technique

Historically, the key to why all kinds of high-power circuit breakers installed in the power supply and distribution equipment of the power system can connect or disconnect various load circuits according to people's will, especially to reliably disconnect short-circuit fault circuits It lies in the arc extinguishing function of the circuit breaker arc extinguishing system.

As we all know, when operating a non-no-load circuit, the movable contact and the static contact of the circuit breaker will form a strong electric field at the rated voltage due to the small distance before the connection or the moment after the disconnection, causing medium or air ionization shock. wear, thereby generating an arc between the moving and static contacts. The greater the operating current and the higher the rated voltage in the circuit, the more serious the arc will be. In 1KV (1000V) and below systems, the anti-arc technology is relatively easy and the cost is relatively low. However, the anti-arc technology and cost of 3KV (3000V) and above high-voltage systems cannot be ignored. For a 10KV oil-less circuit breaker, only when breaking a short-circuit current of 20KA level, the arc power generated by it can reach more than 10 megawatts (10000KW), and the arc column temperature between the dynamic and static contacts of the circuit breaker It can reach 6000-7000 degrees Celsius, or even exceed 10,000 degrees Celsius. The arc can cause phase-to-phase short-circuit faults in the circuit where it is located, and the short-circuit arc will cause huge and vicious accidents in the power system. Therefore, without arc extinguishing technology, it is impossible to connect and disconnect high-power load circuits, and it is even more impossible to remove faulty circuits. Only by ensuring safe arc extinguishing can the successful operation of the circuit breaker to connect or disconnect the load circuit, especially at the moment when the main contact of the circuit breaker disconnects the short-circuit fault current, if the arc cannot be reliably extinguished, it will inevitably lead to a devastating disaster.

So far, the high-voltage circuit breakers above 3KV that are generally operated online in power systems are mainly and commonly divided into three categories: "oil circuit breakers" (divided into "more oil switch" and "low oil switch"), vacuum circuit breakers and SF6 (sulfur hexafluoride) circuit breaker. Among them, insulating oil is installed in the sealed arc extinguishing chamber of the oil circuit breaker, and the main contacts of the circuit breaker are immersed in the oil to work, and the strong arc generated at the moment of the on-off circuit is accelerated by the insulation effect of the oil and the isolation effect from the air; The sealed arc extinguishing chamber of the vacuum circuit breaker is highly vacuumed, and the arc is suppressed by using the insulation effect of the vacuum; while the arc extinguishing chamber of the SF6 circuit breaker is filled with sulfur hexafluoride liquid for arc extinguishing. Oil circuit breakers have the risk of explosion, splashing, burning, etc. in case of failure at any time to expand the scope of accidents, so they are gradually being replaced by vacuum circuit breakers and SF6 circuit breakers; while vacuum circuit breakers have complex structures, complex maintenance, and large breaking. The current capacity is limited; SF6 circuit breakers have ideal interrupting and arc extinguishing effects, but their complexity and cost exceed those of vacuum circuit breakers; there are also circuit breakers with other arc extinguishing methods, but they are not widely used due to technical or safety reasons. The medium and high voltage circuit breaker products with arc extinguishing as the cutting-edge topic have been continuously deduced, changed and introduced since their inception. The design must first solve the arc extinguishing function. The opening or closing of the main contact of any kind of high-voltage circuit breaker must simultaneously meet the four conditions of "confined space, arc extinguishing medium, arc blowing airflow and contact high temperature resistance". To this end, it is necessary to consider the high reliability of the arc extinguishing chamber process, ensure the scientific and reasonable arc blowing system, use high temperature resistant precious alloy materials for the switch contacts, and consider the quality and purity of the arc extinguishing medium. In order to extinguish the arc, the circuit breaker The structure of the circuit breaker cannot be simplified, and the cost remains high. Figure 4-Figure 7 shows the structural diagram of the arc extinguishing chamber of a traditional high-voltage circuit breaker and the schematic diagram of the arc extinguishing scheme.

Oil circuit breakers were born in 1895 and promoted before 1930, and are currently mainly used in high-voltage systems of 3, 6, 10KV and above. Vacuum circuit breakers first appeared in the 1950s (the independent development of vacuum circuit breakers in my country began in the 1970s). At first they were common in ~380/220V systems and ~690V systems, and then gradually entered 3, 6, and 10KV systems. The SF6 circuit breaker is a new type of circuit breaker developed in recent years, most commonly used in 10KV power distribution systems. The cost, service life, structural form and electrical performance of these circuit breakers are mainly determined by the arc extinguishing function and the quality of the main contact alloy. ) The powerful arc generated in an instant does not cause accidents, which is always the most critical point in product development and design. Although the arc extinguishing requirements make the structure of the circuit breaker extremely complicated and the cost increased several times, it has been continued in practice; although the arc extinguishing technology at home and abroad has been improving and innovating, the cheapest scientific method has not been found. The subject of arc extinguishing Always unavoidable.

The development of power electronics technology has promoted the birth of high-power power electronic switches and modules. Since the change of the on or off state of the power electronic module is the result of the diffusion and stop diffusion of free electrons inside the semiconductor material, no arc occurs during the process. , which inspired people to replace mechanical switches (contact switches) with power electronic switches (that is, non-contact switches). Non-contact switch products developed and progressed in full swing in the 1990s, and people in the industry believed that all kinds of high-power circuit breakers would enter the "non-contact" era. However, in practice, it is found that high-power power electronic modules carry load current for a long time to generate large power consumption, and their unavoidable thermal hidden dangers bring greater risks and hidden dangers to system safety, so they cannot replace mechanical switches, let alone medium , High voltage power circuit breaker.

For more than 100 years since the birth of power circuit breakers, experts in product research and development have always focused on the subject of arc extinction and struggled to solve key problems; and since the birth of power electronics technology for decades, experts in product research and development have always focused on high efficiency, high speed and low heat. , No one cares about the changes in the basic structure and basic mode of the circuit breaker, and no one has introduced a high-power circuit breaker solution that can avoid switching arcs and avoid the risk of online heat loss.

Contents of the invention

The utility model provides a non-arc type supercharged bridge high-voltage power circuit breaker for solving the technical problems of high-voltage circuit breaker arc prevention and arc extinguishing, which is composed of a mechanical switch K and a non-contact supercharged bridge switch (hereinafter referred to as "bridge switch"). "or "bridge"), controller P, input and output monitoring instruments V1 and V2, the non-contact booster bridge switch bridge switch uses diodes D1, D2, D3, D4 as bridge arms, and non-contacts connected in series The switch group T1-Tn is a bridge, the connection point of the positive pole of D1 and the negative pole of D2 is the input end of the bridge switch, the connection point of the positive pole of D3 and the negative pole of D4 is the output end of the bridge switch, and the input end of the bridge switch and the input end of the K contact are connected to the high voltage input (IR) terminal, the bridge switch output terminal and the K contact output terminal are connected to the high voltage output (OUT) terminal, the control pole of T1-Tn is connected to P. When switching on, the switch group is first connected and the K contact is connected later, and the arc-free on-off characteristics of the switch group are used to eliminate the arc risk of the circuit breaker.

The utility model is a non-arc type supercharged bridge-type high-voltage power circuit breaker, which effectively combines the excellent characteristics of non-contact switches that can be turned on and off without arcs and the characteristics of mechanical switches that carry current on-line without heat hazards, and Avoid the disadvantages of both, and ensure that the opening or closing of the K contact does not generate arcs. Using this arc-free high-voltage circuit breaker to replace the above-mentioned various existing high-voltage circuit breakers can be widely used in 3KV, 6KV, 10KV, 22KV, In high-voltage power systems such as 33KV and 66KV, by extension, if ultra-high-voltage high-power power electronic switches are successfully developed, such circuit breakers can also be widely used in ultra-high-voltage power systems.

The implementation of this patent can completely change the structure of the traditional high-voltage circuit breaker with a history of one hundred years, and lead to major progress and changes in the basic structure, control and protection circuits of high-voltage circuit breakers, and can quickly stimulate power electronic device developers and manufacturers. Point the R&D interest and goal of power electronic devices to the field of ultra-high voltage, thereby promoting the birth of new power switch products in the field of ultra-high voltage, and promoting the development and production of arc-free circuit breakers in the field of ultra-high voltage, thereby promoting the field of power switches Technological changes and leaps.

The outstanding advantage of this patent is that it completely avoids the problem of arc prevention and control faced by high-voltage circuit breakers, saves all additional mechanisms specially designed for arc extinguishing, and greatly simplifies the basic structure and control and protection circuits of high-voltage circuit breakers. The large cost of circuit breakers (manpower, technology, and materials) doubles its safety, reliability, and service life. It is also especially suitable for realizing intelligent control, which is conducive to the construction of future smart grids.

Description of drawings

Figure 1 is a schematic diagram of the single-phase contact structure of this patented product

Figure 2 is a schematic diagram of the three-phase main wiring principle of the patented product

Figure 3 is a schematic diagram of the basic structure of the arc extinguishing chamber of a traditional circuit breaker

Figure 4 is a schematic diagram of the vertical blowing system in the arc extinguishing chamber of a traditional circuit breaker

Figure 5 is a schematic diagram of the horizontal blowing system in the arc extinguishing chamber of a traditional circuit breaker

Figure 6 is a schematic diagram of the vertical and horizontal blowing system in the arc extinguishing chamber of a traditional circuit breaker

Figure 7 is a schematic diagram of the ring blowing system in the arc extinguishing chamber of a traditional circuit breaker

Figure 1 and Figure 2 are only divided into single-phase and three-phase, and their working principles are exactly the same, but the mechanical switch K in the three-phase circuit breaker can be an integration of three-phase contacts synchronously linked by the same coil or driving device Mechanical switches, which may also consist of three separate single-phase mechanical switches.

Detailed ways

As shown in Figures 1 and 2, the arc-free bridge high-voltage circuit breaker is composed of a non-contact mechanical switch K, a bridge switch, a controller P, and monitoring instruments V1 and V2. The point is connected to the power input (IR) end, the bridge switch output end and the K contact output end are connected to the power output (OUT) end at the same point, the control pole of the switch group in the bridge switch is connected to P, and the control line of P is also connected to the coil of K or Drive unit and V1 and V2.

According to the connection mode and quantity of the non-contact switch tubes in the bridge switch, the non-contact channels in the arc-free bridge high-voltage power circuit breaker are divided into bridge type, expansion bridge type, booster bridge type, and amplification bridge type. , strong control bridge type, expansion strong control bridge type, booster strong control bridge type and expansion strong control bridge type, etc., collectively referred to as "bridge switch". The expansion bridge type described in this patent is characterized by Diodes D1, D2, D3, and D4 are used as bridge arms, and parallel non-contact switch groups (T1, T2...Tn, n≥2) are used as bridges. The principle is as follows:

Opening process (that is, tripping process): before opening, the K contact carries current, and the switch group (T1T2...Tn) can be in the cut-off state or in the conduction state (the closing of the K contact makes the input and output of the bridge switch The voltage between the terminals is close to 0, and the current flowing through it is also close to 0), when a circuit fault is detected and it is determined that the switch needs to be opened or a manual switch is received, P first controls T1T2...Tn to conduct reliably, and then controls When the K contact is broken, the load current or fault current flowing through the K contact will be automatically transferred to the channel of the switch group as the K main contact is disconnected. After the load current is transferred without arc between the K contact and the bridge switch Wait for the K contact to open the signal, and after receiving the signal that the K contact has been reliably broken, the bridge switch is immediately closed (T1T2...Tn is cut off), and there is no arc during the cut-off process of T1T2...Tn, and the circuit breaker is in the whole circuit breaker process. There is no arc generated in the process, and the whole process can be completed within 10ms-100ms (adjustable).

After the circuit is broken (that is, the circuit breaker is opened), P ensures that the K contact is in the open state and the bridge switch is always in the closed state (cut off T1, T2...Tn) to ensure that there will be no closing malfunction.

Closing process (that is, the process of switching on): When the bridge switch and the main contacts of K are both in the open circuit state, when the closing demand signal (preparation and automatic switching signal) or the manual closing command is detected, P first The switch of the control group is turned on (T1T2...Tn is turned on). When the signal of reliable conduction of the switch group is detected, the K contact is immediately controlled to close. Since the switch group has been turned on and carries the full load current before the K contact is closed, the K The input and output of the contact are closed when the voltage is close to 0, so no arc is generated. After the K contact is closed, it will automatically take over the switch group to carry the load current (the input and output of the bridge switch are close to the K The main contact of the main contact is short-circuited), and then the bridge switch channel can continue to be opened (without affecting the work of K, and will not generate heat), or it can be automatically closed (T1T2...Tn is cut off), and the controller P enters into the circuit voltage , current, and the monitoring and monitoring status of bridge switch parameters, and prepare for emergency tripping and fault alarming.

The mechanical switch K refers to an ordinary relay or other electronically controlled mechanical switch without an arc extinguishing device, which does not require a special alloy, and can be divided into a moving contact and a static contact, or can be indistinguishable Mechanical switches with moving and static contacts can also be electromagnetic energy storage or mechanical energy storage switches with current-carrying main contacts. The main contacts are controlled by the action coil or drive device, while the power coil or drive device is controlled by Based on P, it can also be controlled by a relay or contactor controlled by P. The input and output of the main contact of K are respectively connected to the input and output of the bridge switch.

The bridge switch uses diodes D1, D2, D3, and D4 as bridge arms, and n switch tubes (T1T2...Tn) connected in series as a bridge, and the positive pole of D1 and the negative pole of D2 are connected at the same point as the input terminal, and the positive pole of D3 and the negative pole of D4 are connected at the same point as the input terminal. The common point connection of the negative pole is used as the output terminal, the negative pole of D1, the negative pole of D3 and the positive pole of T1 are connected at the same point, the positive pole of D2, the positive pole of D4 and the negative pole of Tn are connected at the same point, and the control poles of T1T2...Tn are connected at the common point of P. In the polarity connection rules Under the same condition, the positions of diodes D1-D4 and T1T2...Tn in the bridge switch can be interchanged. The outlets of the K contacts are connected to the power output (OUT) at the same point, D1-D4 can be high-voltage power diodes, T1T2...Tn are half-controlled or fully-controlled high-voltage power electronic switches or modules, such as: SCR, GTR, GTO, IGBT, IGCT, IEGT, SIT, BSIT, SITH, IPM, PIC, MOSFET or P-MOSFET, etc.

The controller P can be a computer, a single-chip microcomputer or a chip, a control board, an industrial computer (such as PLC, etc.), a control instrument or an intelligent control module, etc. The signal line of P is connected with the current or voltage monitoring instrument (V1, V2), and its control line must be connected with the control pole of the switch group, and also be connected with the control coil or driving device of K.

The monitoring instruments V1 and V2 can be any kind of power conversion device (such as voltage or current converter, waveform distortion rate or voltage fluctuation amplitude or current change rate converter class) or monitoring instruments or monitoring devices (such as Huo Seoul components), etc., are respectively installed in the input (IR) end and output (OUT) end of the circuit breaker in an isolated mode, and its signal line is connected to P.

Affected by the actual withstand voltage level of high-power power electronic devices, the utility model is mainly suitable for high-voltage system circuit breakers of various voltage levels such as 3KV, 6KV, 10KV, 33KV, 66KV, etc. Those skilled in the art know that the technical idea of the present invention Under the framework, high-power power electronic devices can be used in series to achieve arc-free switching of power systems at higher voltage levels. After the successful advent of high-power, high-voltage power electronic devices, high-power high High voltage level power electronic devices cooperate with ordinary mechanical switches to achieve arc-free on-off in higher voltage fields. Therefore, the scope of voltage application of the utility model is not limited, as long as it uses power electronic devices or modules combined with ordinary mechanical switches to form arc-free power circuit breakers or high-power arc-free Switch is exactly the scope of protection of this patent.

Claims (5)

1. one kind without electric arc type supercharging bridge-type high-tension electricity circuit breaker, it is characterized in that: by mechanical switch K, contactless supercharging bridge switch, controller P, input and output measuring instrument V1 and V2 are formed, contactless supercharging bridge switch bridge switch is with diode D1, D2, D3, D4 is brachium pontis, with the noncontacting switch group T1-Tn connected mutually for bridge, with D1 positive pole and D2 negative pole tie point for bridge switch enters to hold, with D3 positive pole and D4 negative pole tie point for bridge switch goes out to hold, bridge switch enters end and K contact and enters hold and together connect high input voltage (IR) and hold, bridge switch goes out end and K contact and goes out hold and together connect High voltage output (OUT) and hold, the control pole of T1-Tn meets P, during breaker open operation, first break and break after switches set in K contact, during combined floodgate, switches set is first led to and leads to behind K contact, utilize the electric arc risk eliminating circuit breaker without electric arc break-make characteristic of switches set.

2. according to claim 1 without electric arc type supercharging bridge-type high-tension electricity circuit breaker, feature is: mechanical switch K, can be can divide into moving contact and fixed contact, also can be the mechanical switch not distinguishing dynamic and static contact, can also be the Power Flow or mechanical energy storage switch etc. with current-carrying main contacts, its contact enter end and go out to hold respectively connecting bridge enter end and bridge go out hold, actuation coil or the drive unit of K are controlled by P, also can be controlled by the relay controlled by P or contactor.

3. according to claim 1 without electric arc type supercharging bridge-type high-tension electricity circuit breaker, it is characterized in that: bridge switch, with diode D1, D2, D3, D4 is bridge wall, with the noncontacting switch group T1-Tn connected mutually for bridge, with D1 positive pole and D2 negative pole tie point for bridge switch enters to hold, D3 positive pole and D4 negative pole tie point are that bridge switch goes out to hold, D1 negative pole is connected with the positive pole concurrent of T1 with D3 negative pole, D2 positive pole is connected with the negative pole concurrent of Tn with D4 positive pole, bridge enters end and K contact and enters hold and together connect power supply input (IR) and hold, bridge goes out end and K contact and goes out hold to connect together power supply and export (OUT) and hold, the control pole concurrent of T1-Tn connects P, D1-D4 is high pressure resistant Power Diode Pumped, T1-Tn is high-tension electricity electronic switching tube or module, optional SCR, GTR, GTO, IGBT, IGCT, IEGT, SIT, BSIT, SITH, IPM, PIC, MOSFET or P-MOSFET.

4. according to claim 1 without electric arc type supercharging bridge-type high-tension electricity circuit breaker, it is characterized in that: controller P, can be computer, single-chip microcomputer, industrial computer, control board, control instrument, intelligent control module, the holding wire of P connects measuring instrument V1, V2 and artificial outer input signal device, and its control line connects the control pole of T1-Tn and the actuation coil of K or drive unit.

5. according to claim 1 without electric arc type supercharging bridge-type high-tension electricity circuit breaker, it is characterized in that instrument V1 and the V2 with monitoring function, it is a kind of electrical transformation device, can be voltage changer or power pack, wave distortion instrument, voltage fluctuation instrument, current changing rate instrument, electric quantity monitoring instrument or monitoring devices, be installed in input and the output of circuit breaker respectively with the pattern of isolation, its holding wire meets P.