Low-voltage AC/DC control and protection electrical appliance

Abstract

A low-voltage AC / DC control and protection for electrical appliance, comprising: a closing flat coil (A) , a metal disk (B), an opening flat coil (E), a shaft (G), a magnetic enhancement board (K), a buffer (X), a control circuit (F), a voltage regulation circuit (Y), a capacitor (C1, C2), a power electronic device (D1, D2, D3, D4), a making and breaking location holding mechanism (H), a shaft sleeve (L), a moving contact bridge bracket (N) and a dual-break contact arc extinguishing system (I).According to the different requirements of normal making and breaking, and breaking in a failure state of the circuit, the control circuit (F) controls the capacitor (C1, C2) to respectively discharge to the closing flat coil (A) and the opening flat coil (E) via the power electronic device (D1, D2, D3, D4) according to the designed optimization control time, the magnetic enhancement board (K) greatly enhances the magnetic field, the metal disk (B) drives the shaft (G) to move under the action of strong electromagnetic repulsion, and the shaft (G) drives electrical appliance contacts to realize rapid making and breaking of the circuit in normal and failure states, thereby replacing the existing conventional electromagnet or motor actuation mechanism and the mechanical actuation mechanism.The low-voltage AC / DC control and protection for electrical appliance has the function of controlling the normal making and breaking of the electrical appliance, electrical appliance fault protection functions including a short circuit fault protection function, and a voltage dip resisting function, rapid action can be realized, the performance index of the electrical appliance can be greatly improved, and has the characteristics of a simplified structure, reduced volume and increased working flux.

Description

technical field [0001] The invention relates to a low-voltage AC / DC control and protection electrical appliance, which belongs to the field of low-voltage electrical appliances. Background technique [0002] At present, low-voltage electrical products mainly include two categories, namely control appliances and protection appliances. Control appliances are divided into AC control appliances and DC control appliances, and protection appliances are further divided into AC protection appliances and DC protection appliances. , for the control and protection of the circuit, it is necessary to install both control electrical appliances and protective electrical appliances. A set of control electrical appliance action mechanism and contact arc extinguishing system is required, as well as a set of protective electrical appliance action mechanism and contact arc extinguishing system. If In order to achieve intelligence, two separate control systems are required. All this not only ma...

AI Technical Summary

Problems solved by technology

[0002] At present, low-voltage electrical products mainly include two categories, namely control appliances and protection appliances. Control appliances are divided into AC control appliances and DC control appliances, and protection appliances are further divided into AC protection appliances and DC protection appliances. , for the control and protection of the circuit, it is necessary to install both control electrical appliances and protective electrical appliances. A set of control electrical appliance action mechanism and contact arc extinguishing system is required, as well as a set of protective electrical appliance action mechanism and contact arc extinguishing system. If In order to achieve intelligence, two separate control systems are required. All this not only makes it difficult for the two to operate well, but also makes it difficult to improve their performance, resulting in a great waste of economy and functions, resulting in complex structures, large volumes, and large installation areas. High cost; currently all low-voltage electrical appliances use electromagnet or motor action mechanism or mechanical action mechanism, the action mechanism of contactor adopts electromagnet action mechanism, and the action mechanism of circuit breaker adopts mechanical action mechanism or motor or both Yes, due to the small speed and slow action of these action mechanisms, it is impossible to improve the performance indicators of their control and protection. This is the second serious problem of low-voltage AC and DC control and protection appliances.

At present, the low-voltage integrated electrical appliances with contactor control function and circuit breaker protection function also combine the control electrical structure and the protective electrical structure. These traditional action mechanisms still have the above serious problems. For example, the "with fast electromagnetic repulsion In the "phase-separated intelligent low-voltage double-break point integrated electrical appliance" patent, although a set of contact arc extinguishing system has been adopted, the function and structure integration have been realized, but the two sets of actions of the electromagnet system and the fast electromagnetic repulsion mechanism are still used. The mechanism adopts the rapid release of the action mechanism under the action of the fast electromagnetic repulsion mechanism to realize the rapidity of short-circuit fault protection. The electromagnet system is still used in normal connection and breaking, which cannot realize fast connection and breaking, and the fast electromagnetic repulsion of this scheme The organization did not consider taking measures to increase the magnetic flux generated by the flat coil to increase the electromagnetic repulsion or reduce the burden on the capacitor; for example, Zhang Peiming et al. obtained the patent "A Smart AC Contactor" (Patent No. ZL00214192.2), which controls The first-open phase contact opens in a small area before the current crosses zero, and the current breaks when the first-open phase current crosses zero, and then controls the other two non-first-open phase contacts to open with a delay of about 5ms, so as to realize the zero-current breaking of the three-phase contacts (the The concept is actually micro-arc energy breaking), the difficulty of this technology is the accuracy and stability of the first-open phase contact breaking, due to the slow action speed of the electromagnet action mechanism of traditional electrical appliances, the long time of connecting and breaking, and the serious action of the mechanism Dispersion cannot guarantee the reliability of good zero-voltage connection and zero-current breaking; existing electrical products do not have the function of anti-voltage drop, and very few studies propose to increase the function of anti-voltage drop. In order to increase the function of anti-voltage drop, many measures must be taken. For example, the patented technology "AC-DC general-purpose anti-voltage drop contactor controller" (public number: CN201584367.U) proposed by Liu Xiangjun and others; in addition, low-voltage control appliances are characterized by frequent operation and require high electrical and mechanical life Therefore, in addition to requiring fast action speed of electrical appliances, the impact energy of the action mechanism is also required to be small. The control and protection electrical appliances must take into account the high electrical life and mechanical life during normal connection and breaking, and must meet the requirements of high short-circuit breaking capacity. , which is the key issue that must be considered in the control and protection of electrical appliances

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