CN201191573Y - Single phase intelligent composite switch - Google Patents

Abstract

The utility model relates to a single-phase intelligent combination switch, which is characterized by comprising a sequential control unit, rapid thyristor, a high-power diode, a high-power magnetic protection relay and a zero-cross measurement-control overvoltage protection module. The single-phase intelligent combination switch adopts a combined utilization technique of modern power electronic and relays, which not only can greatly improve the performance and the reliability of switches and greatly reduce the volumes, but also can greatly lower the manufacture cost of switches, and the module can simply satisfy the requirements of general consumers, and the single-phase intelligent combination switch can be conveniently matched with capacitors in other factories.

Description

Single-phase intelligent composite switch

technical field

The utility model relates to an executive switch, in particular to an intelligent composite switch used in a low-voltage distribution network.

Background technique

Due to the low investment in reactive power compensation equipment of 0.4KV low-voltage distribution network, remarkable energy-saving effect, large market demand, and wide coverage, the promotion and application of reactive power compensation technology and equipment in this field have always been highly favored by governments at all levels, power companies The management department, the majority of power users, and equipment manufacturers attach great importance and concern. The particularly critical unit in this equipment is the switching switch. In the past, the switching response speed of the products used by people was slow, and it was easy to produce switching oscillations. During the switching process, overvoltage and large inrush current were generated, and the contacts were ignited and sintered, causing the switches and capacitors to be damaged. The service life is relatively short. In recent years, a more advanced switching switch has appeared in the market. It is composed of fuses, AC contactors, thermal relays and bidirectional thyristors. It can realize zero-crossing non-contact switching, and the switching process is seamless. The voltage and inrush current are small or even no inrush current, which prolongs the service life of capacitors and switches, and can also meet the requirements of special occasions such as inflammable and explosive (such as coal mines, gas stations and other occasions where sparks are not allowed in switching devices). But the price is expensive, the circuit is complicated, and the wiring is inconvenient, which is difficult for ordinary users to accept.

Contents of the invention

The utility model is aimed at the slow switching response speed of the currently used switching switch, which cannot be frequently operated, overvoltage and large inrush current are generated during the switching process, and the contacts are ignited and sintered, resulting in a relatively short service life of the switch and the capacitor. A good switching switch is expensive and inconvenient to use, so we provide a cost-effective and easy-to-use single-phase intelligent composite switch. It has the advantages of advanced functions, simple wiring, flexible configuration, cost saving, and optional matching.

The technical solution of the utility model is: a single-phase intelligent composite switch, which is characterized in that the composite switch consists of a sequence control unit, a fast thyristor, a high-power diode, a high-power magnetic protection relay, and a zero-crossing measurement and control overvoltage protection module. Composed of five units, fast thyristor, high-power diode, high-power magnetic protection relay, and zero-crossing measurement and control overvoltage protection module, the four units are connected in parallel, among which the fast thyristor and high-power diode are anti-parallel, fast and controllable The control action signal of silicon, high-power magnetic latching relay and zero-crossing measurement and control overvoltage protection module comes from the control unit, and the control unit signal comes from an external controller.

Because the utility model adopts the combined use technology of power electronics and relays, not only the performance and reliability of the switch are greatly improved, the volume is greatly reduced, but also the manufacturing cost of the switch is greatly reduced, so that the module can easily meet the needs of general consumers and reduce the Customers can easily use it with capacitors from other manufacturers. It has the advantages of advanced functions, simple wiring, flexible configuration, and cost savings. It is an ideal replacement product for some functional device combinations in traditional reactive power compensation circuits.

Description of drawings

Fig. 1 is a schematic diagram of a single-phase intelligent composite switch of the present invention.

Detailed ways

Below in conjunction with specific embodiment, further set forth the utility model. It should be understood that these embodiments are only used to illustrate the present utility model and are not intended to limit the scope of the present utility model. In addition, it should be understood that after reading the content taught by the utility model, those skilled in the art can make various changes or modifications to the utility model, and these equivalent forms also fall within the scope defined by the appended claims of the application.

As shown in Figure 1, a single-phase intelligent composite switch has an input of I and an output of O. The intelligent composite switch consists of a control unit 1, a fast thyristor 2, a high-power diode 3, a high-power magnetic protection relay 4, and zero-crossing measurement and control overvoltage. Protection module 5 consists of five units, four units of fast thyristor 2, high-power diode 3, high-power magnetic protection relay 4, and zero-crossing measurement and control overvoltage protection module 5 are connected in parallel, among which fast thyristor 2 and high-power diode 3 is anti-parallel connection, the control terminals of fast thyristor 2, high-power magnetic latching relay 4 and zero-crossing measurement and control overvoltage protection module 5 are connected to the control unit, and the input signal comes from an external controller.

The single-phase intelligent composite switch adopts the domestic advanced composite technology of fast thyristor, high-power diode, and high-power magnetic latching relay. It realizes the function of equal voltage or zero voltage input, current zero crossing cut off, and utilizes the advantage of no power consumption in the working state of the magnetic latching relay. It avoids the possible damage of the thyristor as a pure switch that is powered on for a long time and the internal junction temperature rises. A large number of practices have proved that the domestic thyristor chip KP50 series is used as a switch for switching a single capacitor below 20Kvar/450V and rated current below 25.7A. It has short switching time (hundreds of microseconds), withstand voltage above 1500V, and withstand current shock The technical parameters of 940A can fully meet the requirements and are more than enough. Therefore, this type of switch is completely feasible in terms of manufacturing technology, and the use function is completely satisfactory. In addition to the zero-crossing trigger circuit of similar products, the intelligent composite switch also adds a zero-crossing measurement and control overvoltage protection module: thyristor conduction detection circuit and thyristor overvoltage and breakdown protection circuit to ensure that zero-crossing triggers the thyristor And under the premise of complete conduction, the magnetic latching relay is closed again to prevent the thyristor from triggering and closing the magnetic latching relay in the case of non-conduction, and the burning contact will cause serious consequences that the capacitor cannot be cut off. The adoption of protection technology has greatly improved the reliability and safety of the intelligent composite switch, which is a function that other similar products do not have. In addition, the intelligent composite switch adopts the main circuit composed of thyristor and diode in antiparallel connection (similar products are antiparallel connection of double thyristors), so that the voltage at both ends of the capacitor can actively track the change of the highest voltage of the power grid, effectively preventing the damage caused by the antiparallel connection of double thyristors. The capacitor charging voltage drops, reducing the surge current generated when the thyristor is misconducted and put into the capacitor, protecting the capacitor and switch, and prolonging the service life of the equipment.

Claims (1)

1. A single-phase intelligent composite switch, characterized in that the composite switch consists of a sequence control unit (1), a fast silicon controlled rectifier (2), a high-power diode (3), a high-power magnetic protection relay (4), an over Zero measurement and control overvoltage protection module (5) consists of five units; fast thyristor (2), high-power diode (3), high-power magnetic protection relay (4), and zero-crossing measurement and control overvoltage protection module (5) four The units are connected in parallel, wherein the fast thyristor (2) and the high-power diode (3) are in anti-parallel connection; the fast thyristor (2), the high-power magnetic latching relay (4), and the zero-crossing measurement and control overvoltage protection module (5 ) control action signal comes from the sequence control unit (1), and the control unit (1) signal comes from an external controller.

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