Patent Description:
This application relates to the field of circuit technologies, and in particular, to a reverse power connection preventing circuit for a circuit breaker, a power distribution apparatus, and a power supply and distribution system.

A storage battery is an important component of a power supply and distribution system. As a direct current backup power supply in the power supply and distribution system, the storage battery provides a safe, stable, and reliable power guarantee for a communications device when alternating current power supply is interrupted or fails for short time, thereby ensuring normal operation of the communications device. In the power supply and distribution system, as shown in <FIG>, a storage battery <NUM> is usually connected to a system bus by using a circuit breaker <NUM>. Due to manual wiring, an operational error, shown in <FIG>, that cables of the storage battery <NUM> are reversely connected is unavoidable, and device damage and a safety accident that are caused by the reverse connection of the storage battery <NUM> sometimes occur.

Currently, to prevent a short-circuit caused by a reverse connection of a storage battery, as shown in <FIG>, a magnetic contactor <NUM> is connected in series behind the circuit breaker <NUM>, and voltage sampling circuits <NUM> and <NUM> are respectively disposed at two ends of the magnetic contactor <NUM>. Only when determining that voltages detected by the two voltage sampling circuits <NUM> and <NUM> have same polarity, a control unit <NUM> sends an instruction for closing the magnetic contactor <NUM>.

In the foregoing solution, when the storage battery <NUM> is reversely connected and the circuit breaker <NUM> is switched on, the voltage sampling circuit <NUM> at one end that is of the magnetic contactor <NUM> and that is close to the circuit breaker <NUM> samples a voltage of the reversely connected storage battery <NUM>, and the voltage sampling circuit <NUM> at the other end of the magnetic contactor <NUM> samples a voltage on the system bus. Therefore, the voltages of the two ends are inconsistent, and the magnetic contactor <NUM> is not closed, thereby preventing a short-circuit failure. However, adding the magnetic contactor and the voltage sampling circuits causes higher costs, a larger volume, a higher loss, and a higher heat dissipating requirement.

<CIT> relates to a protective relay comprising input terminals for connection to an external power source; output terminals for connection to a protected circuit or component; a contact connected in series to the input terminal and the output terminal; a reverse bias diode connected to the input terminal; and a relay coil connected to the diode and operatively connected to the contact; wherein upon a reverse current polarity, the diode will energize the relay coil to open the contact and prevent current from reaching the output terminals.

<CIT> relates to a circuit breaker for interrupting a direct current in an electrical system, comprising a main current path that includes a switch; and a reed relay for detecting an electric current flow across the main current path, wherein the switch is coupled to the reed relay.

<CIT> relates to a control circuit for preventing a battery from being reversely connected, wherein the circuit comprises a normally-open contactor, a first normally-open relay, a first diode, a second diode, a second normally-open relay, a third diode, and a controller; the normally-open contactor has a first contact serving as a first input terminal of the control circuit, and a second contact connected to a cathode of the first diode; an anode of the first diode is connected to a movable contact of the first normally-open relay, and a fixed contact of the first normally-open relay is connected to a second terminal of a control coil of the normally-open contactor; a first terminal of the control coil of the normally-open contactor is connected to a cathode of the third diode, and an anode of the third diode serves as a second input terminal of the control circuit; a first terminal of a control coil of the first normally-open relay is connected to a movable contact of the second normally-open relay, and a second terminal of the control coil of the first normally-open relay is connected to an anode of the second diode, a cathode of the second diode is connected to the first contact of the normally-open contactor; a fixed contact of the second normally-open relay is connected to a common terminal between the first terminal of the control coil of the normally-open contactor and the cathode of the third diode, and two terminals of the control coil of the second normally-open relay are connected to the output terminals of the controller; the anode of the third diode is a first output terminal of the control circuit, and the second contact of the normally-open contactor is a second output terminal of the control circuit; and a positive power supply input terminal and a negative power supply input terminal of the controller are connected to the first output terminal and the second output terminal of the control circuit, respectively.

<CIT> relates to a circuit breaker comprising a power terminal section for connection with a distribution line composed of a voltage line and a neutral line, said power terminal section comprised of a line terminal for connection with said voltage line and a neutral terminal for connection with said neutral line; a load terminal section for connection with a load; a contact disposed in a main current path between said power terminal section and said load terminal section; and a drive mechanism which opens said contact for interrupting said main current path when a shorting current or an overload current is detected to flow through the main current path, wherein neutral line voltage responsive means is provided to detect a voltage difference between said neutral line at a point offset from said contact towards said power terminal and a ground terminal for connection with an external ground, said means actuating said drive mechanism for opening the contact when said detected voltage difference becomes greater than a predetermined value.

This application provides a reverse power connection preventing circuit for a circuit breaker, a power distribution apparatus, and a power supply and distribution system, to avoid a loss caused by a reverse connection between a power supply and a circuit breaker.

According to a first aspect of the present invention, as defined in claim <NUM>, this application provides a reverse power connection preventing circuit for a circuit breaker.

The circuit breaker comprises a positive input terminal, a negative input terminal and a switch on mechanism configured to control the circuit breaker to be closed or open when being manipulated. The reverse power connection preventing circuit includes a diode and an actuation unit that are connected in series. The diode and the actuation unit that are connected in series are configured to connect the positive input terminal and the negative input terminal of the circuit breaker. A positive electrode of the diode points to the negative wiring terminal of the circuit breaker, and a negative electrode of the diode points to the positive input terminal of the circuit breaker. When a power supply is forward connected to the circuit breaker, the diode is cut off, there is no current on the actuation unit, and the reverse power connection preventing circuit is in a power-off state. When the power supply is reversely connected to the circuit breaker, the diode is conducted, and the actuation unit is configured to prevent closing of the circuit breaker, or the actuation unit is configured to perform an alarm prompt, to perform an early warning to prompt an operator not to close the circuit breaker. Certainly, the actuation unit may be alternatively configured to: when the diode is conducted, prevent closing of the circuit breaker and also perform an alarm prompt. Therefore, a short-circuit accident caused by the reverse connection of the power supply is completely prevented. Furthermore, the reverse power connection preventing circuit also ensures safety of on-site construction, thereby fundamentally avoiding a safety risk caused by the reverse connection. In addition, the reverse power connection preventing circuit provided in this application is simple in structure, so that a volume and costs can be reduced compared with the conventional technology.

The reverse power connection preventing circuit provided in this application further includes a current limiting resistor. After being connected in series to the diode and the actuation unit, the current limiting resistor is configured to connect the positive input terminal and the negative input terminal of the circuit breaker. The current limiting resistor can limit a current flowing through the diode and the actuation unit, thereby reducing power consumption and protecting components.

The reverse power connection preventing circuit provided in this application may further include a fuse. After being connected in series to the current limiting resistor, the diode, and the actuation unit, the fuse is configured to connect the positive input terminal and the negative input terminal of the circuit breaker. The fuse is blown due to overcurrent during a lightning surge, to prevent a case in which because lightning breaks down the diode, the circuit breaker cannot be normally closed when the power supply is forward connected.

The actuation unit is specifically configured to lock the switch on mechanism when the diode is conducted.

Further, when the actuation unit is configured to lock the switch on mechanism when the diode is conducted, the actuation unit may include an electromagnet, and a clamping slot is disposed on the switch on mechanism of the circuit breaker. The electromagnet is connected in series to the diode and the current limiting resistor. The electromagnet is configured to: when the diode is conducted, drive an armature of the electromagnet to be inserted into the clamping slot, to lock the switch on mechanism of the circuit breaker to prevent closing of the circuit breaker.

In a possible implementation, the circuit breaker includes a switch off mechanism. The switch off mechanism is configured to: when being driven, control the circuit breaker to be in an open state. The actuation unit is specifically configured to drive the switch off mechanism when the diode is conducted.

Further, when the actuation unit is specifically configured to drive the switch off mechanism when the diode is conducted, the actuation unit may include a first electromagnetic tripper. The first electromagnetic tripper is connected in series to the diode and the current limiting resistor. The first electromagnetic tripper is configured to drive the switch off mechanism of the circuit breaker when the diode is conducted, to control the circuit breaker to be in the open state. Optionally, the circuit breaker further includes a second electromagnetic tripper. An iron core of the second electromagnetic tripper is reused as an iron core of the first electromagnetic tripper. An armature of the second electromagnetic tripper is reused as an armature of the first electromagnetic tripper. The original components of the second electromagnetic tripper are reused. It is equivalent that the actuation unit includes only a third coil sleeved onto a second iron core of the second electromagnetic tripper. Therefore, a structure of the reverse power connection preventing circuit is simplified, so that both a volume of the reverse power connection preventing circuit and costs can be reduced.

Further, when the actuation unit is specifically configured to drive the switch off mechanism when the diode is conducted, the actuation unit includes a first thermal tripper. The first thermal tripper is connected in series to the diode and the current limiting resistor. The first thermal tripper is configured to drive the switch off mechanism of the circuit breaker when the diode is conducted, to control the circuit breaker to be in the open state.

Optionally, the circuit breaker further includes a second thermal tripper. The second thermal tripper includes a thermal deformation metal. The second thermal tripper is reused as the first thermal tripper, that is, the second thermal tripper needs to be connected in series to the diode and the current limiting resistor, to avoid adding an additional thermal tripper. Therefore, a structure of the reverse power connection preventing circuit is simplified, so that both a volume of the reverse power connection preventing circuit and costs can be reduced.

Alternatively, when the circuit breaker further includes the second thermal tripper, the actuation unit includes a heat emitting element. The heat emitting element is connected in series to the diode and the current limiting resistor. The heat emitting element is configured to deform the thermal deformation metal when the diode is conducted, to drive the switch off mechanism of the circuit breaker to control the circuit breaker to be in the open state.

In another implementable embodiment, the actuation unit may further include a buzzer and/or a prompt light. When the power supply is reversely connected, the diode is conducted, and the buzzer sends a sound alarm, the prompt light sends a light alarm, or the buzzer sends a sound alarm and simultaneously the prompt light sends a light alarm, to perform an early warning to prompt an operator not to close the circuit breaker. When the power supply is forward connected, the diode is cut off, and the actuation unit is not powered on.

In this application, when the reverse power connection preventing circuit includes the fuse, and the actuation unit includes the electromagnet, the fuse is reused as at least a part of a coil of the electromagnet.

According to a second aspect of the present invention, as defined in dependent claim <NUM>, this application further provides a power distribution apparatus, including a circuit breaker and the foregoing reverse power connection preventing circuit. The reverse power connection preventing circuit is connected between a positive input terminal and a negative input terminal of the circuit breaker. According to a third aspect of the present invention, as defined in dependent claim <NUM>, this application further provides a power supply and distribution system, including a power supply and the foregoing power distribution apparatus. A positive electrode of the power supply is connected to a positive input terminal of a circuit breaker in the power distribution apparatus, and a negative electrode of the power supply is connected to a negative input terminal of the circuit breaker in the power distribution apparatus.

To make objectives, technical solutions, and advantages of this application clearer, the following further describes this application in detail with reference to the accompanying drawings. However, the example implementations may be implemented in a plurality of forms, and it should not be understood as being limited to the example implementations described herein. Conversely, the implementations are provided to make this application more comprehensive and complete, and comprehensively convey the idea of the example implementations to a person skilled in the art. Same reference signs in the drawings represent same or similar structures, and therefore repeated descriptions thereof are omitted. Words that express positions and directions and that are described in this application are all descriptions provided by using the accompanying drawings as an example, but changes may be made as required, and the made changes shall be all included in the protection scope of this application. The accompanying drawings of this application are used to illustrate only a relative position relationship, and do not represent a true proportion.

It should be noted that specific details are set forth in the following description for ease of fully understanding this application. However, this application can be implemented in a plurality of manners different from those described herein, and a person skilled in the art can perform similar promotion without departing from the connotation of this application. Therefore, this application is not limited to the following disclosed specific implementations. The following descriptions of this specification are example manners of implementing this application. However, the descriptions are intended to describe the general principle of this application, and are not intended to limit the scope of this application. The protection scope of this application shall be defined by the appended claims.

To facilitate understanding of a reverse power connection preventing circuit provided in an embodiment of this application, the following first describes a specific application scenario of the reverse power connection preventing circuit. The reverse power connection preventing circuit provided in this embodiment of this application may be widely applied to various power supply and distribution systems. For example, <FIG> shows a possible application scenario according to an embodiment of this application. As shown in <FIG>, a power supply and distribution system includes a power supply <NUM>, a circuit breaker <NUM>, and a reverse power connection preventing circuit <NUM>. The circuit breaker <NUM> is configured to conduct, carry, or cut off a current between a power supply network and electric equipment. When a circuit between the power supply network or the power supply and the electric equipment needs to be connected, the circuit breaker <NUM> may be switched to a closed state. When the circuit between the power supply network and the electric equipment needs to be disconnected, the circuit breaker <NUM> may be switched to an open state. As a backup power supply in the power supply and distribution system, the power supply <NUM> provides a safe, stable, and reliable power guarantee for a communications device when alternating current power supply is interrupted or fails for short time, thereby ensuring normal operation of the communications device. The power supply <NUM> may be a storage battery, an electric generator, or the like. Because the power supply <NUM> is usually manually connected to the circuit breaker <NUM>, an operational error that cables of the power supply <NUM> are reversely connected is unavoidable. If the reverse power connection preventing circuit <NUM> in this application is not disposed, the reverse connection of the power supply <NUM> may cause device damage and a safety accident.

However, because the reverse power connection preventing circuit <NUM> is disposed in the power supply and distribution system, the reverse power connection preventing circuit <NUM> can determine, when the power supply <NUM> is connected to the circuit breaker <NUM> and before the circuit breaker <NUM> is closed, whether the power supply is reversely connected, and perform an early warning or prevent closing of the circuit breaker, to avoid a short-circuit current generated by the reverse connection. To facilitate understanding of the circuit breaker provided in this embodiment of this application, the following specifically describes, with reference to specific embodiments and accompanying drawings, the circuit breaker provided in this application.

<FIG> is a schematic diagram of a structure of the reverse power connection preventing circuit according to an embodiment of this application. Referring to <FIG>, the reverse power connection preventing circuit <NUM> provided in this embodiment of this application includes a diode <NUM> and an actuation unit <NUM> that are connected in series. The diode <NUM> and the actuation unit <NUM> that are connected in series are configured to connect a positive input terminal A1 and a negative input terminal A2 of the circuit breaker. A positive electrode of the diode <NUM> points to the negative wiring terminal A2 of the circuit breaker, and a negative electrode of the diode <NUM> points to the positive input terminal A1 of the circuit breaker. When the power supply is forward connected to the circuit breaker, the diode <NUM> is cut off, there is no current on the actuation unit <NUM>, and the reverse power connection preventing circuit <NUM> is in a power-off state. When the power supply is reversely connected to the circuit breaker, the diode <NUM> is conducted, and the actuation unit <NUM> is configured to prevent closing of the circuit breaker, or the actuation unit <NUM> is configured to perform an alarm prompt, to perform an early warning to prompt an operator not to close the circuit breaker. Certainly, the actuation unit <NUM> may be alternatively configured to: when the diode <NUM> is conducted, prevent closing of the circuit breaker and also perform an alarm prompt. Therefore, a short-circuit accident caused by the reverse connection of the power supply is completely prevented. Furthermore, the reverse power connection preventing circuit also ensures safety of on-site construction, thereby fundamentally avoiding a safety risk caused by the reverse connection. In addition, the reverse power connection preventing circuit provided in this application is simple in structure, so that a volume and costs can be reduced compared with the conventional technology.

For example, as shown in <FIG>, the reverse power connection preventing circuit <NUM> provided in this application may further include a current limiting resistor <NUM>. After being connected in series to the diode <NUM> and the actuation unit <NUM>, the current limiting resistor <NUM> is configured to connect the positive input terminal A1 and the negative input terminal A2 of the circuit breaker (not shown in <FIG>). The current limiting resistor <NUM> can limit a current flowing through the diode <NUM> and the actuation unit <NUM>, thereby reducing power consumption and protecting components.

For example, as shown in <FIG>, the reverse power connection preventing circuit <NUM> provided in this application may further include a fuse <NUM>. After being connected in series to the current limiting resistor <NUM>, the diode <NUM>, and the actuation unit <NUM>, the fuse <NUM> is configured to connect the positive input terminal A1 and the negative input terminal A2 of the circuit breaker (not shown in <FIG>). The fuse is blown due to overcurrent during a lightning surge, to prevent a case in which because lightning breaks down the diode, the circuit breaker cannot be normally closed when the power supply is forward connected.

It should be noted that positions of the diode <NUM>, current limiting resistor <NUM>, actuation unit <NUM>, and fuse <NUM> are not limited in this application, provided that the four components are connected in series.

The following describes this application in detail with reference to specific embodiments. It should be noted that the embodiments are intended to better explain the present invention, but are not intended to limit this application.

During specific implementation, referring to <FIG>, the circuit breaker <NUM> may include a housing <NUM> and a switch on mechanism <NUM> disposed on the housing <NUM>. Switching of the circuit breaker <NUM> between the closed state and the open state may be implemented by controlling the switch on mechanism <NUM>. The circuit breaker <NUM> further includes input terminals and output terminals that are disposed in the housing <NUM>. The input terminals are configured to be connected to a power supply line, and the output terminals are configured to be connected to a power receiving line. There are two input terminals: a positive input terminal A1 and a negative input terminal A2. The positive input terminal A1 is configured to be connected to a positive electrode of the power supply line, and the negative input terminal A2 is configured to be connected to a negative electrode of the power supply line. There are two output terminals: a positive output terminal B1 and a negative output terminal B2. The positive output terminal B1 is configured to be connected to a positive electrode of the power receiving line, and the negative output terminal B2 is configured to be connected to a negative electrode of the power receiving line.

To enable the power supply line to be electrically connected to the power receiving line by using the circuit breaker <NUM>, the positive input terminal A1 may be electrically connected to the positive output terminal B1, and the negative input terminal A2 may be electrically connected to the negative output terminal B2. In addition, still referring to <FIG>, to enable the circuit breaker <NUM> to control an on/off status between the input terminal and the output terminal, an on/off control system <NUM> is usually disposed in the circuit breaker <NUM>. A power supply on/off status of the electric equipment can be controlled by controlling either of a connection between the positive input terminal A1 and the positive output terminal B1 and a connection between the negative input terminal A2 and the negative output terminal B2. Based on this, a process of controlling the on/off status between the input terminal and the output terminal in this embodiment of this application is described by using an example in which the on/off control system <NUM> is disposed between the positive input terminal A1 and the positive output terminal B1. To connect the negative input terminal A2 to the negative output terminal B2, a connection manner may be but is not limited to a direct electrical connection performed by using a conducting wire.

Still referring to <FIG>, the circuit breaker <NUM> further includes a slide buckle <NUM> and a switch off structure <NUM>. The switch off structure <NUM> is configured to: when being driven, control the circuit breaker <NUM> to be in the open state. The switch off structure <NUM> may include a connecting rod mechanism <NUM> and a rotating shaft <NUM>. The positive input terminal A1 is connected to a first contact Q1 of the on/off control system <NUM>, and the positive output terminal B1 is connected to a second contact Q2 of the on/off control system <NUM>. When the switch on mechanism <NUM> is pushed in a direction close to the slide buckle <NUM>, the switch on mechanism <NUM> pushes the connecting rod mechanism <NUM> to rotate around the rotating shaft <NUM>, so that a first connecting rod <NUM> of the connecting rod mechanism <NUM> pushes the first contact Q1 of the on/off control system <NUM> to rotate towards the second contact Q2, until the first contact Q1 is in contact with the second contact Q2. In this way, the positive input terminal A1 and the positive output terminal B1 are in a circuit-conducted state, so that the circuit breaker <NUM> is closed. When the switch on mechanism <NUM> is pulled out in a direction away from the slide buckle <NUM>, the connecting rod mechanism <NUM> rotates around the rotating shaft <NUM> in a reverse direction, so that the first contact Q1 of the on/off control system <NUM> rotates in a direction away from the second contact Q2. In this way, the positive input terminal A1 and the positive output terminal B1 are in a circuit-broken state, so that the circuit breaker <NUM> is open.

In a use process of the circuit breaker <NUM>, a short-circuit failure may occur in the power receiving line. If the power supply line still supplies electric energy to the power receiving line after the failure occurs, a severer accident may be caused. Therefore, there is a relatively severe safety risk. To improve safety between the power supply line and the power receiving line, during specific implementation, an electromagnetic tripper may be further disposed in the circuit breaker. A second electromagnetic tripper <NUM> in <FIG> is used as an example. When the short-circuit failure exists in the power receiving line, the second electromagnetic tripper <NUM> drives the switch off mechanism <NUM>, so that the switch off structure <NUM> controls the circuit breaker <NUM> to be in the open state, thereby implementing short-circuit protection. For example, referring to <FIG>, the second electromagnetic tripper <NUM> mainly includes an electromagnet. The second electromagnetic tripper <NUM> may include a second coil <NUM>, a second iron core <NUM>, and a second armature <NUM>. The second coil <NUM> is sleeved onto the second iron core <NUM>. One end of the second coil <NUM> may be electrically connected to the second contact Q2 by using a conductor (for example, a metal wire or a metal sheet), and the other end may be electrically connected to the positive output terminal B1. A current of the positive input terminal A1 flows to the positive output terminal B1 after passing through the conductor and the second coil <NUM>. When the short-circuit failure exists in the power receiving line, a current flowing through the second coil <NUM> is excessively large. When the current exceeds a preset current threshold of the circuit breaker <NUM>, the second coil <NUM> generates a relatively large magnetic field, so that the second iron core <NUM> generates an electromagnetic force for moving the second armature <NUM>. When the second iron core <NUM> acts on the second armature <NUM>, a second connecting rod <NUM> of the connecting rod mechanism <NUM> is pushed. The second connecting rod <NUM> causes the connecting rod mechanism <NUM> to rotate around the rotating shaft <NUM>, so that the first contact Q1 moves in the direction away from the second contact Q2, until the first contact Q1 is separated from the second contact Q2. Therefore, a current path between the positive input terminal A1 and the positive output terminal B1 is cut off, thereby implementing short-circuit protection.

In addition to a short-circuit risk, an overload failure may alternatively occur in the power receiving line. If the power supply line still supplies electric energy to the power receiving line after the failure occurs, a severer accident may be caused. Therefore, there is a relatively severe safety risk. To further improve safety between the power supply line and the power receiving line, a thermal tripper may be further disposed in the circuit breaker. A second thermal tripper <NUM> in <FIG> is used as an example. When the overload failure exists in the power receiving line, the second thermal tripper <NUM> drives the switch off mechanism <NUM>, so that the switch off structure <NUM> controls the circuit breaker <NUM> to be in the open state, thereby implementing overload protection.

For example, referring to <FIG>, the second thermal tripper <NUM> may include a first thermal deformation metal. One end of the first thermal deformation metal may be electrically connected to the second contact Q2, and the other end may be electrically connected to the positive output terminal B1. When the overload failure exists in the power receiving line, a large amount of heat is generated in the power receiving line. When the amount of heat exceeds a preset heat threshold of the circuit breaker <NUM>, the first thermal deformation metal is deformed, and a third connecting rod <NUM> causes the connecting rod mechanism <NUM> to rotate around the rotating shaft <NUM>, so that the first contact Q1 moves in the direction away from the second contact Q2, until the first contact Q1 is separated from the second contact Q2. Therefore, a current path between the positive input terminal A1 and the positive output terminal B1 is cut off, thereby implementing overload protection.

The following describes in detail a working principle of the reverse power connection preventing circuit in this application with reference to some specific implementations of the actuation unit.

First case: The actuation unit may be specifically configured to lock the switch on mechanism when the diode is conducted. That is, when the power supply is reversely connected, the diode in the reverse power connection preventing circuit is conducted. However, because the actuation unit can lock the switch on mechanism, the switch on mechanism can be prevented from being manipulated, thereby preventing closing of the circuit breaker.

In a possible implementation, as shown in <FIG>, the actuation unit may include a first electromagnet <NUM>, and a clamping slot <NUM> is disposed on the switch on mechanism <NUM> of the circuit breaker <NUM>. The first electromagnet <NUM> is connected in series to the diode <NUM> and the current limiting resistor <NUM>. The first electromagnet <NUM> is configured to: when the diode <NUM> is conducted, drive an armature of the first electromagnet <NUM> to be inserted into the clamping slot <NUM>, to lock the switch on mechanism <NUM> of the circuit breaker <NUM>, thereby preventing closing of the circuit breaker <NUM>. For example, as shown in <FIG>, the first electromagnet <NUM> includes a first coil <NUM>, a first iron core <NUM>, and a first armature <NUM>. The first coil <NUM> is connected in series to the diode <NUM> and the current limiting resistor <NUM>. When the power supply is reversely connected, referring to <FIG>, the diode <NUM> is conducted, and the first coil <NUM> is powered on and drives the first armature <NUM> to be inserted into the clamping slot <NUM>, to lock the switch on mechanism <NUM> of the circuit breaker <NUM>, thereby preventing closing of the circuit breaker <NUM>. When the power supply is forward connected, referring to <FIG>, the diode <NUM> is cut off, the first armature <NUM> is away from the clamping slot <NUM>, and the reverse power connection preventing circuit <NUM> is in a power-off state and does not act on the circuit breaker <NUM>.

During specific implementation, the clamping slot <NUM> may be disposed at any position that can lock the switch on mechanism <NUM>. This is not limited herein.

In addition, in this application, when a fuse is disposed in the reverse power connection preventing circuit <NUM>, the fuse may be reused as at least a part of the first coil <NUM>. Specifically, this may be implemented by adjusting a structure and a material of a part of the first coil <NUM>. This is not limited herein.

Second case: The actuation unit in this application may be specifically configured to drive the switch off mechanism when the diode is conducted. That is, when the power supply is reversely connected, the diode in the reverse power connection preventing circuit is conducted. However, because the actuation unit can drive the switch off mechanism, the switch off mechanism controls the circuit breaker to be in the open state.

In a possible implementation, as shown in <FIG>, in the reverse power connection preventing circuit in this application, the actuation unit may include a first electromagnetic tripper <NUM>. The first electromagnetic tripper <NUM> is connected in series to the diode <NUM> and the current limiting resistor <NUM>. The first electromagnetic tripper <NUM> is configured to drive the switch off mechanism <NUM> of the circuit breaker <NUM> when the diode <NUM> is conducted, to control the circuit breaker <NUM> to be in the open state. For example, as shown in <FIG>, the first electromagnetic tripper <NUM> mainly includes an electromagnet. The first electromagnetic tripper <NUM> may include a third coil <NUM>, a third iron core <NUM>, and a third armature <NUM>. The third coil <NUM> is connected in series to the diode <NUM> and the current limiting resistor <NUM>. When the power supply is reversely connected, the diode <NUM> is conducted, and a current of the negative input terminal A2 flows to the positive input terminal A1 after passing through the third coil <NUM>. The current flowing through the third coil <NUM> generates a relatively large magnetic field, so that the third iron core <NUM> generates an electromagnetic force for moving the third armature <NUM>. After the third armature <NUM> is moved by the third iron core <NUM>, the third armature <NUM> pushes a fourth connecting rod <NUM> of the connecting rod mechanism <NUM>. The fourth connecting rod <NUM> causes the connecting rod mechanism <NUM> to rotate around the rotating shaft <NUM>, so that the first contact moves in the direction away from the second contact, until the first contact is separated from the second contact. Therefore, a current path between the positive input terminal A1 and the positive output terminal B1 is cut off, so that the circuit breaker <NUM> is in the open state.

In another possible implementation, as shown in <FIG>, in the reverse power connection preventing circuit in this application, the second iron core <NUM> of the second electromagnetic tripper <NUM> is reused as a third iron core of the first electromagnetic tripper, and the second armature <NUM> of the second electromagnetic tripper <NUM> is reused as an armature of the first electromagnetic tripper. That is, the third coil <NUM> is sleeved onto the second iron core <NUM> of the second electromagnetic tripper <NUM>. When the power supply is reversely connected, the diode <NUM> is conducted, and a current of the negative input terminal A2 flows to the positive input terminal A1 after passing through the third coil <NUM>. The current flowing through the third coil <NUM> generates a relatively large magnetic field, so that the second iron core <NUM> generates an electromagnetic force for moving the second armature <NUM>. When the second iron core <NUM> acts on the second armature <NUM>, the second connecting rod <NUM> of the connecting rod mechanism <NUM> is pushed. The second connecting rod <NUM> causes the connecting rod mechanism <NUM> to rotate around the rotating shaft <NUM>, so that the first contact moves in the direction away from the second contact, until the first contact is separated from the second contact. Therefore, a current path between the positive input terminal A1 and the positive output terminal B1 is cut off, so that the circuit breaker <NUM> is in the open state. Compared with the embodiment in <FIG>, in this embodiment, the original components of the second electromagnetic tripper <NUM> are reused. It is equivalent that the actuation unit <NUM> includes only the third coil <NUM> sleeved onto the second iron core <NUM> of the second electromagnetic tripper <NUM>. Therefore, a structure of the reverse power connection preventing circuit is simplified, so that both a volume of the reverse power connection preventing circuit and costs can be reduced.

In addition, in this application, when a fuse is disposed in the reverse power connection preventing circuit <NUM>, the fuse may be reused as at least a part of the third coil <NUM>. Specifically, this may be implemented by adjusting a structure and a material of a part of the third coil <NUM>. This is not limited herein.

During specific implementation, the electromagnet has a plurality of structural forms. Based on a magnetic path system form, the plurality of structural forms may be classified into a snap-fit type, a disk type, an E-shaped type, a solenoid type, and the like. Based on an armature movement manner, the plurality of structural forms may be classified into a rotating type and a direct-acting type. This is not limited herein.

For example, in this application, as shown in <FIG>, an electromagnet <NUM> mainly includes three parts: a coil <NUM>, an iron core <NUM>, and an armature <NUM>. The iron core <NUM> and the armature <NUM> are usually made of a soft magnetic material, the iron core <NUM> is usually stationary, and the coil <NUM> is sleeved onto the iron core. The electromagnet <NUM> further includes a spring. When the coil <NUM> is powered on, the iron core and the armature are magnetized to become two magnets with opposite polarity or same polarity. An electromagnetic attraction force or repulsion force is generated between the two magnets. When the attraction force or repulsion force is greater than a reaction force of the spring, the armature starts to move towards the iron core <NUM> or against the iron core <NUM>. When a current in the coil <NUM> is less than a preset value, or power supply is interrupted, an electromagnetic force is less than a reaction force of the spring, and the armature <NUM> returns to an original release position under the action of the reaction force.

In another possible implementation, as shown in <FIG>, the actuation unit <NUM> includes a first thermal tripper <NUM>. The first thermal tripper <NUM> is connected in series to the diode <NUM> and the current limiting resistor <NUM>. The first thermal tripper <NUM> is configured to drive the switch off mechanism <NUM> of the circuit breaker <NUM> when the diode <NUM> is conducted, to control the circuit breaker <NUM> to be in the open state. For example, as shown in <FIG>, the first thermal tripper <NUM> includes a second thermal deformation metal, and the second thermal deformation metal is connected in series to the diode <NUM> and the current limiting resistor <NUM>. When the power supply is reversely connected, the second thermal deformation metal is deformed, and a fifth connecting rod <NUM> causes the connecting rod mechanism <NUM> to rotate around the rotating shaft <NUM>, so that the first contact moves in the direction away from the second contact, until the first contact is separated from the second contact. Therefore, a current path between the positive input terminal A1 and the positive output terminal B1 is cut off, so that the circuit breaker <NUM> is in the open state.

In another possible implementation, as shown in <FIG>, the original second thermal tripper <NUM> in the circuit breaker <NUM> is reused as the first thermal tripper <NUM>, and the second thermal tripper <NUM> needs to be connected in series to the diode <NUM> and the current limiting resistor <NUM>. When the power supply is reversely connected, the diode <NUM> is conducted, the first thermal deformation metal in the second thermal tripper <NUM> is deformed, and the third connecting rod <NUM> causes the connecting rod mechanism <NUM> to rotate around the rotating shaft <NUM>, so that the first contact moves in the direction away from the second contact, until the first contact is separated from the second contact. Therefore, a current path between the positive input terminal A1 and the positive output terminal B1 is cut off, so that the circuit breaker <NUM> is in the open state. Compared with the embodiment in <FIG>, in this embodiment, the second thermal tripper <NUM> is reused as the first thermal tripper <NUM>, to avoid adding an additional thermal tripper. Therefore, a structure of the reverse power connection preventing circuit is simplified, so that both a volume of the reverse power connection preventing circuit and costs can be reduced.

In another possible implementation, as shown in <FIG>, the actuation unit <NUM> includes a heat emitting element. The heat emitting element is connected in series to the diode <NUM> and the current limiting resistor <NUM>. The heat emitting element is configured to deform the first thermal deformation metal of the second thermal tripper <NUM> in the circuit breaker <NUM> when the diode is conducted, to drive the switch off mechanism <NUM> of the circuit breaker <NUM> to control the circuit breaker <NUM> to be in the open state. Specifically, when the power supply is reversely connected, the diode <NUM> is conducted, the heat emitting element deforms the first thermal deformation metal of the second thermal tripper <NUM> in the circuit breaker <NUM>, and the third connecting rod <NUM> causes the connecting rod mechanism <NUM> to rotate around the rotating shaft <NUM>, so that the first contact moves in the direction away from the second contact, until the first contact is separated from the second contact. Therefore, a current path between the positive input terminal A1 and the positive output terminal B1 is cut off, so that the circuit breaker <NUM> is in the open state.

During specific implementation, the thermal deformation metal may be made of a shape memory alloy. The shape memory alloy is a material that has a shape memory effect through thermoelasticity, Martensite phase transformation, and inverse Martensite phase transformation and that is made of more than two metal elements. The thermal deformation metal made of the shape memory alloy may be embodied as follows: After being plastically deformed in a specific temperature range, the thermal deformation metal can recover to an original shape in another temperature range. For example, at a normal temperature or a relatively low temperature, the thermal deformation metal made of the shape memory alloy keeps or approximately keeps in a straight line shape after being straightened. After the thermal deformation metal is heated to a specific temperature, the thermal deformation metal may automatically recover to an original curve shape. In addition, the thermal deformation metal may be alternatively made of a bimetallic finger. The bimetallic finger is a composite material made of two or more metals or other materials with proper properties. The bimetallic finger is also referred to as a thermal bimetallic finger. Due to different coefficients of thermal expansion of component layers, when a temperature changes, deformation of an active layer is greater than deformation of a passive layer, so that the entire bimetallic finger bends toward a passive layer side.

Third case: The actuation unit in this application may include a buzzer and/or a prompt light. When the power supply is reversely connected, the diode is conducted, and the buzzer sends a sound alarm, the prompt light sends a light alarm, or the buzzer sends a sound alarm and simultaneously the prompt light sends a light alarm, to perform an early warning to prompt an operator not to close the circuit breaker. When the power supply is forward connected, the diode is cut off, and the actuation unit is not powered on.

Fourth case: The third case is combined with the first case or the second case. That is, in this application, when an implementation of the actuation unit is the first case or the second case, the actuation unit may further include a buzzer and/or a prompt light. In this way, when the power supply is reversely connected, the reverse power connection preventing circuit can prevent closing of the circuit breaker, and also perform an alarm prompt.

Referring to <FIG>, this application further provides a power distribution apparatus <NUM>, including a circuit breaker <NUM> and a reverse power connection preventing circuit <NUM>. The reverse power connection preventing circuit <NUM> is connected to a positive input terminal A1 and a negative input terminal A2 of the circuit breaker <NUM>. A problem resolving principle of the power distribution apparatus <NUM> is similar to that of the foregoing reverse power connection preventing circuit <NUM>. Therefore, for an implementation of the power distribution apparatus <NUM>, refer to the foregoing implementation of the reverse power connection preventing circuit <NUM>. Repeated parts are not described again.

Referring to <FIG>, this application further provides a power supply and distribution system <NUM>, including a power supply <NUM> and a power distribution apparatus <NUM>. A positive electrode of the power supply <NUM> is connected to a positive input terminal A1 of a circuit breaker <NUM> in the power distribution apparatus <NUM>, and a negative electrode of the power supply <NUM> is connected to a negative input terminal A2 of the circuit breaker <NUM> in the power distribution apparatus <NUM>. The power supply and distribution system <NUM> may be a power supply and distribution system of a <NUM> (5th generation, <NUM> for short) high-power radio base station, or may be a power supply and distribution system of a home circuit. An application field of the power supply and distribution system <NUM> is not limited in this embodiment, and the power supply and distribution system <NUM> may be applied to a line connection in any field.

Claim 1:
A reverse power connection preventing circuit (<NUM>) for a circuit breaker (<NUM>), which circuit breaker comprising a positive input terminal (A1), a negative input terminal (A2) and a switch on mechanism (<NUM>) configured to control the circuit breaker (<NUM>) to be closed or open when being manipulated, the reverse power connection preventing circuit (<NUM>) comprising a diode (<NUM>) and an actuation unit (<NUM>) that are connected in series, and further comprising a current limiting resistor (<NUM>) connected in series to the diode (<NUM>) and the actuation unit (<NUM>), wherein
the diode (<NUM>) and the actuation unit (<NUM>) that are connected in series are configured to connect the positive input terminal (A1) and the negative input terminal (A2) of the circuit breaker (<NUM>);
a positive electrode of the diode (<NUM>) points to the negative wiring terminal (A2) of the circuit breaker (<NUM>), and a negative electrode of the diode (<NUM>) points to the positive input terminal (A1) of the circuit breaker (<NUM>); and
the actuation unit (<NUM>) is configured to prevent closing of the circuit breaker (<NUM>) when the diode (<NUM>) is conducted, and/or is configured to perform an alarm prompt when the diode (<NUM>) is conducted; and
characterised in that the actuation unit (<NUM>) is specifically configured to lock the switch on mechanism (<NUM>) when the diode (<NUM>) is conducted.