Fault alarm circuit

Abstract

The utility model provides a fault alarm circuit, the above fault alarm circuit comprises an induction end, a transmitting end and a power supply unit, the induction end comprises a first inductor and a second inductor, the transmitting end comprises a relay, a control unit and a display; the display is electrically connected with the control unit; the first inductor is connected in series with a first pin and a second pin of the control unit to form a first loop; the second inductor is connected in series with a third pin and a fourth pin of the control unit to form a second loop; a first end of the relay is connected in series to the first loop series, and a second end of a second normally-closed switch of the relay is connected in series to the second loop series; and the power supply unit is respectively connected with the first loop, the second loop, the display and the relay. The alarm signals are generated by performing signal acquisition on the first loop and the second loop, so that the situation that fault alarm is not timely is avoided, and the safety is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic circuits, in particular to a fault alarm circuit. Background Art

[0002] With the further development of new energy electric vehicles, the demand for charging piles is growing. However, charging piles may cause abnormal charging and safety accidents due to relay adhesion. In order to solve the problem of relay adhesion, relays with auxiliary switches are generally used to solve the adhesion problem.

[0003] However, the relay with auxiliary switch is large in size, which increases the production cost of the charging pile. In this case, if the charging pile without the relay with auxiliary switch is not used, the fault alarm may not be timely, which increases the danger. Utility Model Content

[0004] The main purpose of the utility model is to provide a fault detection circuit, which aims to solve the problem that if a charging pile without a relay with an auxiliary switch is not used, the fault alarm may not be timely and the circuit may not be truly disconnected.

[0005] To achieve the above object, the utility model provides a fault alarm circuit, characterized in that the fault alarm circuit includes a sensing end, a signal transmitting end and a power supply unit, the sensing end includes a first sensor and a second sensor, and the signal transmitting end includes a relay, a control unit and a display;

[0006] The display is electrically connected to the control unit;

[0007] The first inductor and the first pin and the second pin of the control unit are connected in series to form a first loop;

[0008] The second sensor and the third pin and the fourth pin of the control unit are connected in series to form a second loop;

[0009] The first end of the relay is connected in series to the first loop series, and the second end of the second break switch of the relay is connected in series to the second loop series;

[0010] The power supply unit is respectively connected to the first circuit, the second circuit, the display and the relay; wherein, in a normal state, the relay is in an open and power-off state.

[0011] Optionally, the power supply unit includes a first power supply unit;

[0012] The first power supply unit includes a first resistor and a transistor;

[0013] Among them, the base of the transistor is electrically connected to the fifth pin of the control unit, the collector of the transistor is electrically connected to the magnetic end of the relay, the emitter collector of the transistor is grounded, the first end of the first resistor is electrically connected to the base of the transistor, and the second end of the first resistor is connected to the emitter collector of the transistor, so as to form the first power supply unit to power the relay.

[0014] Optionally, the first inductor further includes a second resistor;

[0015] The first section of the second resistor is connected to the live wire input terminal of the relay, and the second section of the second resistor is connected to the neutral wire input terminal of the relay to form a third loop for current limiting;

[0016] The sensing end of the first sensor is sleeved on the third loop to generate an induced voltage signal.

[0017] Optionally, the first sensor further includes a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first capacitor and a second capacitor;

[0018] The third resistor, the fourth resistor, the fifth resistor, the sixth resistor, the first capacitor, and the second capacitor are electrically connected to form a fourth loop, wherein the third resistor, the fourth resistor, the fifth resistor, and the sixth resistor are connected in series;

[0019] The input end of the first inductor is electrically connected between the third resistor and the fifth resistor, and the output end of the first inductor is electrically connected between the fourth resistor and the sixth resistor;

[0020] The first pin is connected between the fifth resistor and the first capacitor, the second pin is electrically connected between the sixth resistor and the second capacitor, and when the fourth loop is turned on, the first pin and the second pin are used to receive the induced voltage electrical signal.

[0021] Optionally, the second sensor further includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a third capacitor and a fourth capacitor;

[0022] The seventh resistor, the eighth resistor, the ninth resistor, the tenth resistor, the third capacitor and the fourth capacitor are electrically connected to form a fifth loop, wherein the seventh resistor, the eighth resistor, the ninth resistor and the tenth resistor are connected in series.

[0023] Optionally, the fault alarm circuit further includes:

[0024] The induction end of the second inductor is sleeved on the neutral line output end of the relay to generate an induction current signal;

[0025] The input end of the second inductor is electrically connected between the seventh resistor and the ninth resistor, and the output end of the second inductor is electrically connected between the eighth resistor and the tenth resistor;

[0026] The third pin is connected between the ninth resistor and the third capacitor, the fourth pin is electrically connected between the tenth resistor and the fourth capacitor, and when the fifth loop is turned on, the third pin and the fourth pin are used to receive the induced voltage electrical signal.

[0027] Optionally, the display is a liquid crystal display;

[0028] The liquid crystal display screen is electrically connected to the control unit for communication using the SPI protocol.

[0029] The utility model provides a fault alarm circuit, the fault alarm circuit comprises a sensing end, a signaling end and a power supply unit, the sensing end comprises a first sensor and a second sensor, the signaling end comprises a relay, a control unit and a display; the display and the control unit are electrically connected; the first sensor and the first pin and the second pin of the control unit are connected in series to form a first loop; the second sensor and the third pin and the fourth pin of the control unit are connected in series to form a second loop; the first end of the relay is connected in series to the first loop series, and the second end of the second break switch of the relay is connected in series to the second loop series; the power supply unit is connected to the first loop, the second loop, the display and the relay respectively; wherein, in a normal state, the relay is in an open power-off state. In this embodiment, in the case of a charging pile without a relay with an auxiliary switch, the alarm signal is generated by collecting signals of the first loop and the second loop, so as to avoid the untimely alarm due to relay adhesion and improve safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0031] Figure 1 One of the structural schematic diagrams of the fault alarm circuit provided by the embodiment of the utility model;

[0032] The purpose, features and advantages of the present invention will be further described in conjunction with the embodiments and with reference to the accompanying drawings.

[0033] Description of Figure Numbers:

[0034]

[0035] DETAILED DESCRIPTION

[0036] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0037] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0038] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0039] In addition, the descriptions of "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0040] See also Figure 1 , Figure 1 This is one of the structural diagrams of the fault alarm circuit provided by the embodiment of the utility model. The fault alarm circuit provided by the embodiment of the utility model includes a comparator 10 and a switch 20;

[0041] The utility model provides a fault alarm circuit, characterized in that the fault alarm circuit comprises a sensing end, a signal transmitting end and a power supply unit, the sensing end comprises a first sensor and a second sensor, the signal transmitting end comprises a relay, a control unit and a display; the display and the control unit are electrically connected;

[0042] The first sensor and the first pin and the second pin of the control unit are connected in series to form a first loop; the second sensor and the third pin and the fourth pin of the control unit are connected in series to form a second loop; the first end of the relay is connected in series to the first loop, and the second end of the second break switch of the relay is connected in series to the second loop; the power supply unit is connected to the first loop, the second loop, the display and the relay respectively; wherein, under normal conditions, the relay is in an open power-off state.

[0043] Specifically, the control unit can use the MCU control chip to execute signal reception and transmission, and use the control unit to execute the disconnection operation of the relay. The control unit sends a disconnection instruction to the relay, wherein the disconnection instruction can be implemented by using the control unit to send a high level or a low level respectively, and after the relay receives the high level or low level signal, it executes the disconnection or closing operation.

[0044] Furthermore, the first circuit is used to receive a voltage sensing signal, and the second circuit is used to receive a current sensing signal. After executing the disconnection instruction, the control unit determines whether there is relay adhesion based on the returned voltage sensing signal and / or current sensing signal.

[0045] In another preferred embodiment, the power supply unit includes a first power supply unit;

[0046] The first power supply unit includes a first resistor and a transistor; wherein the base of the transistor is electrically connected to the fifth pin of the control unit, the collector of the transistor is electrically connected to the magnetic end of the relay, the emitter collector of the transistor is grounded, the first end of the first resistor is electrically connected to the base of the transistor, and the second end of the first resistor is connected to the emitter collector of the transistor, so as to form a first power supply unit to supply power to the relay.

[0047] In another preferred embodiment, the first sensor also includes a second resistor; the first section of the second resistor is connected to the live wire input terminal of the relay, and the second section of the second resistor is connected to the neutral wire input terminal of the relay to form a third circuit for current limiting; the inductive end of the first sensor is connected to the third circuit to generate an induced voltage signal.

[0048] Furthermore, the first sensor further includes a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first capacitor and a second capacitor;

[0049] The third resistor, the fourth resistor, the fifth resistor, the sixth resistor, the first capacitor and the second capacitor are electrically connected to form a fourth loop, wherein the third resistor, the fourth resistor, the fifth resistor and the sixth resistor are connected in series;

[0050] An input end of the first inductor is electrically connected between the third resistor and the fifth resistor, and an output end of the first inductor is electrically connected between the fourth resistor and the sixth resistor;

[0051] The first pin is connected between the fifth resistor and the first capacitor, the second pin is electrically connected between the sixth resistor and the second capacitor, and when the fourth loop is turned on, the first pin and the second pin are used to receive the induced voltage electrical signal.

[0052] Specifically, the third circuit can be a primary current limiting circuit, and the first inductor can be a voltage transformer, wherein, after the input end of the primary coil of the voltage transformer is energized, it can be transmitted to the secondary coil through magnetic conduction and generate voltage, and a voltage lower than 2.5V can be delivered to the first pin and the second pin of the control unit.

[0053] In another preferred embodiment, the second sensor further includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a third capacitor and a fourth capacitor;

[0054] The seventh resistor, the eighth resistor, the ninth resistor, the tenth resistor, the third capacitor and the fourth capacitor are electrically connected to form a fifth loop, wherein the seventh resistor, the eighth resistor, the ninth resistor and the tenth resistor are connected in series.

[0055] In another preferred embodiment, the induction end of the second inductor is sleeved on the neutral line output end of the relay to generate an induction current signal;

[0056] An input end of the second inductor is electrically connected between the seventh resistor and the ninth resistor, and an output end of the second inductor is electrically connected between the eighth resistor and the tenth resistor;

[0057] The third pin is connected between the ninth resistor and the third capacitor, and the fourth pin is electrically connected between the tenth resistor and the fourth capacitor. When the fifth loop is turned on, the third pin and the fourth pin are used to receive the induced voltage electrical signal.

[0058] Specifically, the second inductor can be an isolated current transformer, and the fifth loop can be a current acquisition circuit. The neutral line of the relay output end passes through the middle of the isolated current transformer ring. After power supply, the current transformer can obtain voltage through magnetic induction, and then deliver the voltage lower than 2.5V to the third pin and the fourth pin of the control unit through the fifth loop.

[0059] In another preferred embodiment, the display is a liquid crystal display screen; the liquid crystal display screen is electrically connected to the control unit for communication using the SPI protocol, and when the control unit detects an abnormal situation, the liquid crystal display screen is used to display a fault to provide a fault prompt.

[0060] As a matter of course, since the energy storage device of this embodiment adopts the technical solution of the above-mentioned fault alarm circuit, the energy storage device has all the beneficial effects described in the above-mentioned embodiments.

[0061] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0062] The serial numbers of the above-mentioned embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0063] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A fault alarm circuit, characterized in that: The fault alarm circuit includes a sensing end, a transmitting end and a power supply unit, the sensing end includes a first sensor and a second sensor, and the transmitting end includes a relay, a control unit and a display; The display is electrically connected to the control unit; The first inductor and the first pin and the second pin of the control unit are connected in series to form a first loop; The second sensor and the third pin and the fourth pin of the control unit are connected in series to form a second loop; The first end of the relay is connected in series to the first loop series, and the second end of the second break switch of the relay is connected in series to the second loop series; The power supply unit is respectively connected to the first circuit, the second circuit, the display and the relay; wherein, in a normal state, the relay is in an open and power-off state.

2. The fault alarm circuit according to claim 1, characterized in that: The power supply unit includes a first power supply unit; The first power supply unit includes a first resistor and a transistor; Among them, the base of the transistor is electrically connected to the fifth pin of the control unit, the collector of the transistor is electrically connected to the magnetic end of the relay, the emitter collector of the transistor is grounded, the first end of the first resistor is electrically connected to the base of the transistor, and the second end of the first resistor is connected to the emitter collector of the transistor, so as to form the first power supply unit to power the relay.

3. The fault alarm circuit according to claim 1, characterized in that: The first inductor further includes a second resistor; The first section of the second resistor is connected to the live wire input terminal of the relay, and the second section of the second resistor is connected to the neutral wire input terminal of the relay to form a third loop for current limiting; The sensing end of the first sensor is sleeved on the third loop to generate an induced voltage signal.

4. The fault alarm circuit according to claim 3, characterized in that: The first sensor further includes a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first capacitor and a second capacitor; The third resistor, the fourth resistor, the fifth resistor, the sixth resistor, the first capacitor, and the second capacitor are electrically connected to form a fourth loop, wherein the third resistor, the fourth resistor, the fifth resistor, and the sixth resistor are connected in series; The input end of the first inductor is electrically connected between the third resistor and the fifth resistor, and the output end of the first inductor is electrically connected between the fourth resistor and the sixth resistor; The first pin is connected between the fifth resistor and the first capacitor, the second pin is electrically connected between the sixth resistor and the second capacitor, and when the fourth loop is turned on, the first pin and the second pin are used to receive the induced voltage electrical signal.

5. The fault alarm circuit according to claim 1, characterized in that: The second sensor further includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a third capacitor and a fourth capacitor; The seventh resistor, the eighth resistor, the ninth resistor, the tenth resistor, the third capacitor and the fourth capacitor are electrically connected to form a fifth loop, wherein the seventh resistor, the eighth resistor, the ninth resistor and the tenth resistor are connected in series.

6. The fault alarm circuit according to claim 5, characterized in that: The fault alarm circuit also includes: The induction end of the second inductor is sleeved on the neutral line output end of the relay to generate an induction current signal; The input end of the second inductor is electrically connected between the seventh resistor and the ninth resistor, and the output end of the second inductor is electrically connected between the eighth resistor and the tenth resistor; The third pin is connected between the ninth resistor and the third capacitor, the fourth pin is electrically connected between the tenth resistor and the fourth capacitor, and when the fifth loop is turned on, the third pin and the fourth pin are used to receive the induced voltage electrical signal.

7. The fault alarm circuit according to claim 1, characterized in that: The display is a liquid crystal display screen; The liquid crystal display screen is electrically connected to the control unit for communication using the SPI protocol.

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