Polarity switching module

Abstract

The utility model aims to provide the polarity switching module which is low in cost and does not cause current surge during live switching. The device comprises a power module, a connector and a switching unit, the power module is connected with the connector through the switching unit, the connector is connected with a product, and the switching unit comprises a first relay, a second relay and a third relay. The positive end of the connector is connected to a first switching port of the first relay and a first switching port of the second relay, the negative end of the connector is connected to a second switching port of the first relay, and the second switching port of the second relay and the positive output end of the power module are connected with a fixed port of the first relay. The first switching port of the third relay is disconnected, the second switching port of the third relay is connected with the fixed port of the second relay, and the negative output end of the power module is connected with the fixed end of the third relay. The circuit switching circuit is applied to the technical field of circuit switching.

Description

Technical Field

[0001] The utility model is applied to the technical field of circuit switching, and particularly relates to a polarity switching module. Background Art

[0002] After the production of batteries is completed, it is usually necessary to carry out a process of capacity division on the batteries. Only after the batteries meet the requirements after capacity division can they be normally used in actual work.

[0003] However, due to differences in battery materials, the polarity of some batteries is reversed, or the polarity is reversed due to improper human operation or incorrect placement of the battery. If the capacity splitting equipment is splitting the battery with reversed polarity, it will cause a short circuit in the battery, causing damage to the circuit or equipment or even a fire. Therefore, the capacity splitting equipment usually has the function of monitoring the polarity of the battery and switching the polarity. The polarity switching of conventional bidirectional DC-DC power output is achieved by two relays. The switch of the relay can only switch from on to off or from off to on, and there is no intermediate state for transition. Due to the differences in the production process of the relay itself and the signal transmission between chips, the two relays cannot switch in unison. One relay will always complete the switching action first, so the battery will short-circuit during this period of time.

[0004] When the chemical separation equipment is powered on, a short circuit in the battery will generate a huge current surge, which can easily damage the relays and other electronic components of the equipment. The battery itself is very easy to over-discharge and even cause combustion and explosion, resulting in cost waste and high safety risks. Damage to relays and other electronic components requires manual troubleshooting and repair, resulting in low work efficiency and a short service life of the chemical separation equipment.

[0005] To this end, if a low-cost polarity switching module that does not cause current surges during live switching can be provided, it will be possible to achieve safe and reliable polarity switching while keeping the circuit simple, thereby improving the service life and work efficiency of the equipment and reducing maintenance costs. Utility Model Content

[0006] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art and provide a polarity switching module which is low in cost and does not cause current surge during live switching.

[0007] The technical solution adopted by the utility model is: the utility model includes a power module, a connector and a switching unit, the power module is connected to the connector through the switching unit, the connector is connected to the product, the switching unit includes a first relay, a second relay and a third relay, the positive end of the connector is connected to the first switching port of the first relay and the first switching port of the second relay, the negative end of the connector is connected to the second switching port of the first relay, the second switching port of the second relay and the positive output end of the power module are both connected to the fixed port of the first relay, the first switching port of the third relay is open, the second switching port of the third relay is connected to the fixed port of the second relay, and the negative output end of the power module is connected to the fixed end of the third relay.

[0008] As can be seen from the above scheme, by setting a third relay and connecting the negative output end of the power module to its fixed end, the on-off control of the entire circuit is realized, and the entire circuit is disconnected when the polarity is switched to avoid short circuit. At the same time, the circuit of the first relay and the second relay is improved. Compared with the traditional connector, the positive and negative poles are respectively connected to the fixed ends of the first relay and the second relay, and the switching port is cross-connected. It can avoid the situation that one of the relays will inevitably short-circuit when it fails and cannot be attracted. However, the first relay and the second relay do not need to work at the same time when the application is working normally. Therefore, when the relay that needs to be attracted fails, there is no relay in the entire circuit to attract, and the circuit will remain disconnected, which will not cause damage to the battery. The overall circuit structure of the present application is simple, and it can ensure that the polarity can be switched safely and reliably under various working conditions, and the safety performance is greatly improved. The service life and work efficiency of the equipment are also improved, reducing maintenance costs.

[0009] A preferred solution is that the power module includes a bidirectional power supply, a PWM controller and a processing unit, the coils of the first relay, the second relay and the third relay are all connected to the processing unit, the bidirectional power supply is connected to the positive output end through a first field effect transistor, the bidirectional power supply is connected to the negative output end through a second field effect transistor, the processing unit is connected to the gates of the first field effect transistor and the second field effect transistor through the PWM controller, and the negative output end is grounded.

[0010] A preferred solution is that an inductor is further provided between the first field effect transistor and the positive output terminal.

[0011] A preferred solution is that an output capacitor is provided between the positive output terminal and the negative output terminal. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a connection structure block diagram of the utility model. DETAILED DESCRIPTION

[0013] like Figure 1 As shown, in this embodiment, the utility model includes a power module 1, a connector 2 and a switching unit 3, the power module 1 is connected to the connector 2 through the switching unit 3, the connector 2 is connected to the product, the switching unit 3 includes a first relay K1, a second relay K2 and a third relay K3, the positive end of the connector 2 is connected to the first switching port of the first relay K1 and the first switching port of the second relay K2, the negative end of the connector 2 is connected to the second switching port of the first relay K1, the second switching port of the second relay K2 and the positive output end of the power module 1 are all connected to the fixed port of the first relay K1, the first switching port of the third relay K3 is open, the second switching port of the third relay K3 is connected to the fixed port of the second relay K2, and the negative output end of the power module 1 is connected to the fixed end of the third relay K3.

[0014] In this embodiment, the first switching ports of the first relay K1, the second relay K2 and the third relay K3 are normally closed ports, and the second switching ports are normally open ports. When the relay is powered off, the movable terminal keeps the normally closed port and the fixed port connected. When the coil of the relay is powered on, the movable terminal is driven to be attracted to the normally open port, so that the normally open port and the fixed port are connected.

[0015] In this embodiment, the power module 1 includes a bidirectional power supply 11, a PWM controller 12 and a processing unit 13. The coils of the first relay K1, the second relay K2 and the third relay K3 are all connected to the processing unit 13. The bidirectional power supply 11 is connected to the positive output terminal through the first field effect transistor Q1, and the bidirectional power supply 11 is connected to the negative output terminal through the second field effect transistor Q2. The source of the first field effect transistor Q1 is connected to the bidirectional power supply 11, the drain of the first field effect transistor Q1 is connected to the positive output terminal, the source of the second field effect transistor Q2 is connected to the negative output terminal, and the drain of the second field effect transistor Q2 is connected between the first field effect transistor Q1 and the positive output terminal.

[0016] The processing unit 13 is connected to the gates of the first field effect transistor Q1 and the second field effect transistor Q2 through the PWM controller 12, and the negative output terminal is grounded. An inductor L is also provided between the first field effect transistor Q1 and the positive output terminal, and the inductor L is used for filtering. An output capacitor C is provided between the positive output terminal and the negative output terminal, and the output capacitor C is used to isolate the positive output terminal from the negative output terminal. The processing unit 13 is a conventional microprocessor, which is used to control the PWM controller 12, the first relay K1, the second relay K2 and the third relay K3.

[0017] As shown in the following table and Figure 1 As shown, when the coils of the first relay K1, the second relay K2 and the third relay K3 are all powered off, the circuit between the battery product and the power module is broken; when the first relay K1 and the second relay K2 are powered on and attracted, and the third relay K3 is powered off, the negative pole of the connector 2 is not connected, so the circuit is also broken.

[0018] ;

[0019] When performing polarity switching, the third relay K3 is powered on first. At this time, no matter the on / off state of the first relay K1 and the second relay K2 is, the circuit is disconnected.

[0020] Therefore, the circuit will be open only when one of the first relay K1 and the second relay K2 is powered on, thereby avoiding the situation where a short circuit or current surge is caused by a delay or failure of the relay, thereby protecting the battery product and other components in the switching unit, achieving safe and reliable polarity switching, improving the service life and working efficiency of the equipment, and reducing maintenance costs.

[0021] Although the embodiments of the present invention are described with practical solutions, they do not constitute limitations on the meaning of the present invention. For those skilled in the art, it is obvious to modify the implementation scheme and combine it with other solutions based on this description.

Claims

1. A polarity switching module, comprising a power module (1), a connector (2) and a switching unit (3), wherein the power module (1) is connected to the connector (2) via the switching unit (3), and the connector (2) is connected to a product, characterized in that: The switching unit (3) comprises a first relay (K1), a second relay (K2) and a third relay (K3); the positive end of the connector (2) is connected to a first switching port of the first relay (K1) and a first switching port of the second relay (K2); the negative end of the connector (2) is connected to a second switching port of the first relay (K1); the second switching port of the second relay (K2) and the positive output end of the power module (1) are both connected to a fixed port of the first relay (K1); the first switching port of the third relay (K3) is disconnected; the second switching port of the third relay (K3) is connected to a fixed port of the second relay (K2); and the negative output end of the power module (1) is connected to a fixed end of the third relay (K3).

2. A polarity switching module according to claim 1, characterized in that: The power module (1) comprises a bidirectional power supply (11), a PWM controller (12) and a processing unit (13); the coils of the first relay (K1), the second relay (K2) and the third relay (K3) are all connected to the processing unit (13); the bidirectional power supply (11) is connected to the positive output end via a first field effect tube (Q1); the bidirectional power supply (11) is connected to the negative output end via a second field effect tube (Q2); the processing unit (13) is connected to the gates of the first field effect tube (Q1) and the second field effect tube (Q2) via the PWM controller (12); and the negative output end is grounded.

3. A polarity switching module according to claim 2, characterized in that: An inductor coil (L) is also provided between the first field effect tube (Q1) and the positive output end.

4. A polarity switching module according to claim 2, characterized in that: An output capacitor (C) is provided between the positive output terminal and the negative output terminal.

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