Inrush current suppression switch

Abstract

The utility model relates to an inrush current suppression switch, in particular to an inrush current suppression switch suitable for capacitive load connection, which comprises a mechanical switch and a resistor, the mechanical switch is a bridging structure, and the mechanical switch comprises a first contact, a second contact and a contact bridge; the first contact is connected with the second contact through the contact bridge, one end of the resistor is connected with the first contact, the other end of the resistor is connected with the contact bridge, and in the closing process of the mechanical switch, the contact bridge is firstly connected with the second contact and then connected with the first contact. The utility model has the advantages of reasonable design, simple circuit and high reliability.

Description

Technical Field

[0001] This utility model relates to an inrush current suppression switch, and more particularly to an inrush current suppression switch that is simple and reliable and suitable for connecting capacitive loads. Background Technology

[0002] With the increasing use of various DC applications, and since a large portion of the load is capacitive (such as DC / DC and DC / AC converters), ordinary switches are prone to sticking together when turned on. Summary of the Invention

[0003] The purpose of this invention is to address the technical issues by providing a cost-effective, simple, and reliable inrush suppression switch.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] A surge current suppression switch includes a mechanical switch and a resistor. The mechanical switch has a bridging structure and includes a first contact, a second contact, and a contact bridge. The first contact is connected to the second contact via the contact bridge (electrical connection). One end of the resistor is connected to the first contact (electrical connection), and the other end of the resistor is connected to the contact bridge (electrical connection). During the closing process of the mechanical switch, the contact bridge is first connected to the second contact and then connected to the first contact.

[0006] This utility model has a reasonable design and the advantages of high cost performance, simple circuit and high reliability. Attached Figure Description

[0007] Figure 1 This is one of the schematic diagrams of an embodiment of the inrush current suppression switch of this utility model.

[0008] Figure 2 This is the second schematic diagram of an embodiment of the inrush current suppression switch of this utility model. Detailed Implementation

[0009] Embodiment 1 of this utility model:

[0010] A surge suppression switch, such as Figure 1 As shown, it includes a mechanical switch S and a resistor R. The mechanical switch S has a bridging structure and includes a first contact N1, a second contact N2, and a contact bridge N3. The first contact N1 is connected to the second contact N2 through the contact bridge N3. One end of the resistor R is connected to the first contact N1, and the other end of the resistor R is connected to the contact bridge N3. During the closing process of the mechanical switch S, the contact bridge N3 is first connected to the second contact N2, and then connected to the first contact N1.

[0011] Working principle: During the closing process of mechanical switch S, the contact bridge N3 is first connected to the second contact N2. The input power charges the capacitor of the load RC through the resistor R, the contact bridge N3, and the second contact N2 to suppress inrush current. Then, the contact bridge N3 is connected to the first contact N1, the resistor R is bypassed, and the mechanical switch S is closed.

[0012] like Figure 2 As shown, a thyristor SCR1 can be connected in series in the middle of the series circuit composed of contact bridge N3, resistor R, and first contact N1. During the opening of mechanical switch S, thyristor SCR1 does not conduct; during the closing of mechanical switch S, thyristor SCR1 conducts after contact bridge N3 is connected to second contact N2, which can further reduce the current surge to second contact N2. The operating power of control unit A connected to thyristor SCR1 is provided by the control power supply connected to mechanical switch S. Control unit A includes resistor R1 and relay K1. Relay K1 is a small or micro relay, and its operating speed is faster than that of mechanical switch S.

[0013] In the above embodiments, when the mechanical switch is a relay (contaminator), considering the effect of gravity, the height of the first contact above the ground is higher than that of the second contact, and the mechanical switch is a DC switch.

[0014] This invention utilizes the advantage of the short connection time (time difference less than 1 millisecond) of the contact bridge to the other two contacts. Combined with a low-resistance resistor, it can further accelerate the charging speed of the capacitor and more effectively suppress the impact of inrush current on the first contact N1. At the same time, since the resistor has an extremely short working time, only a small-volume resistor is needed to meet the requirements. This invention uses a single contact bridge to complete the series and parallel connection of resistors, and has the advantages of simple circuit and high cost performance.

[0015] This utility model has a reasonable design and the advantages of high cost performance, simple circuit and high reliability.

Claims

1. An inrush current suppression switch, comprising a mechanical switch and a resistor, characterized in that: The mechanical switch has a bridging structure and includes a first contact, a second contact, and a contact bridge. The first contact is connected to the second contact via the contact bridge. One end of the resistor is connected to the first contact, and the other end of the resistor is connected to the contact bridge. During the closing process of the mechanical switch, the contact bridge is first connected to the second contact and then connected to the first contact.

2. The inrush current suppression switch according to claim 1, characterized in that: The first contact is higher than the second contact above the ground, and the mechanical switch is a DC switch.

3. The inrush current suppression switch according to claim 1, characterized in that: A thyristor is connected in series in the middle of the series circuit consisting of the contact bridge, the resistor, and the first contact.

4. The inrush current suppression switch according to claim 3, characterized in that: During the disconnection process of the mechanical switch, the thyristor is not conducting.

5. The inrush current suppression switch according to claim 3, characterized in that: During the closing process of the mechanical switch, the thyristor is turned on after the contact bridge is connected to the second contact.

6. The inrush current suppression switch according to claim 3, characterized in that: The control unit connected to the thyristor is powered by the control power supply of the mechanical switch.

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