Alternating current and direct current dual-input circuit and power supply module

Abstract

The utility model relates to an AC / DC dual-input circuit and a power supply module. The code scanning device comprises an AC / DC dual-input circuit, the AC / DC dual-input circuit comprises an AC input control circuit, a DC input control circuit, an AC / DC conversion circuit and a DC bus, a first end of the AC input control circuit is used for connecting an AC input electric signal, and a second end of the AC input control circuit is connected with a first end of the AC / DC conversion circuit; the first end of the DC input control circuit is used for connecting a DC input electric signal, the second end of the DC input control circuit is connected with the second end of the AC-DC conversion circuit, and the second end of the AC-DC conversion circuit is connected with a DC bus. By adopting the alternating current and direct current double-input circuit, uninterrupted power supply for direct current electric equipment can be realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to power supply technical field especially relates to AC-DC double input circuit and power module. BACKGROUND

[0002] The power module product includes the former stage AC-DC (alternating current-direct current) converter and the latter stage isolation DC-DC (direct current-direct current) converter. The direct current electric equipment using the above-mentioned power module can work normally in the environment of alternating city power, is stronger to city power grid dependence, and in the place without city power supply, the equipment will be unable to use. Therefore a kind of power module capable of compatible AC and DC two kinds of input is needed.

[0003] The AC-DC double input circuit in the related art realizes the effect of compatible AC and DC two kinds of input by controlling the number of switch tube connected in AC-DC conversion circuit and switch driving signal.

[0004] However, the above-mentioned AC-DC double input circuit needs to switch about direct current electric equipment when switching AC input and DC input, and uninterrupted power supply to direct current electric equipment cannot be realized. INVENTION CONTENTS

[0005] Therefore, it is necessary to provide an AC-DC double input circuit and power module capable of realizing uninterrupted power supply to direct current electric equipment when switching AC input and DC input.

[0006] In a first aspect, an AC-DC double input circuit is provided, which comprises: an AC input control circuit, a DC input control circuit, an AC-DC conversion circuit and a DC bus; wherein,

[0007] The first end of the AC input control circuit is used for connecting AC input electrical signal, and the second end of the AC input control circuit is connected with the first end of the AC-DC conversion circuit;

[0008] The first end of the DC input control circuit is used for connecting DC input electrical signal, and the second end of the DC input control circuit is connected with the second end of the AC-DC conversion circuit;

[0009] The second end of the AC-DC conversion circuit is connected with the DC bus.

[0010] In one of the embodiments, the AC input control circuit comprises a first relay and an AC pre-charging circuit, wherein,

[0011] The first end of the first relay is used for connecting AC input electrical signal, and the second end of the first relay is connected with the first end of the AC pre-charging circuit;

[0012] The second end of the AC pre-charging circuit is used for connecting the first end of the AC-DC conversion circuit.

[0013] In one of the embodiments, the AC pre-charge circuit comprises a second relay and three single-phase pre-charge resistors, the second relay comprises three second double-pole switches, each second double-pole switch corresponds to each single-phase pre-charge circuit respectively, wherein,

[0014] The first end of the second double-pole switch is connected to the second end of the first relay, the second end of the second double-pole switch is connected to the first end of the corresponding single-phase pre-charge resistor, and the third end of the second double-pole switch is connected to the first end of the AC-DC conversion circuit;

[0015] The second end of the single-phase pre-charge resistor is connected to the first end of the AC-DC conversion circuit.

[0016] In one of the embodiments, the DC input control circuit comprises a third relay and a DC pre-charge circuit, wherein,

[0017] The first end of the third relay is used for connecting a DC input signal, and the second end of the third relay is connected to the first end of the DC pre-charge circuit;

[0018] The second end of the DC pre-charge circuit is used for connecting the second end of the AC-DC conversion circuit.

[0019] In one of the embodiments, the DC pre-charge circuit comprises a fourth relay and two DC pre-charge resistors, wherein the fourth relay comprises two fourth double-pole switches, each fourth double-pole switch corresponds to each DC pre-charge circuit respectively, wherein,

[0020] The first end of the fourth double-pole switch is connected to the second end of the third relay, the second end of the fourth double-pole switch is connected to the first end of the corresponding DC pre-charge resistor, and the third end of the fourth double-pole switch is connected to the second end of the AC-DC conversion circuit;

[0021] The second end of the DC pre-charge resistor is connected to the second end of the AC-DC conversion circuit.

[0022] In one of the embodiments, the AC-DC conversion circuit comprises a first capacitor, a second capacitor and three single-phase conversion circuits; wherein,

[0023] The first end of the single-phase conversion circuit is connected to the corresponding phase output end of the AC input control circuit, the second end of the single-phase conversion circuit is connected to the first end of the first capacitor, the third end of the single-phase conversion circuit is connected to the second end of the first capacitor, and the fourth end of the single-phase conversion circuit is connected to the second end of the second capacitor;

[0024] The first end of the first capacitor is connected to the first end of the DC bus;

[0025] The first end of the second capacitor is connected to the second end of the first capacitor, and the second end of the second capacitor is connected to the second end of the DC bus.

[0026] In one of the embodiments, the single-phase conversion circuit comprises a first diode, a second diode, a first switch tube and a second switch tube, wherein,

[0027] The positive pole of the first diode is connected with the corresponding phase output end of the AC input control circuit, and the negative pole of the first diode is connected with the first end of the first capacitor;

[0028] The positive pole of the second diode is connected with the second end of the second capacitor, and the negative pole of the second diode is connected with the corresponding phase output end of the AC input control circuit;

[0029] The first end of the first switch tube is connected with the corresponding phase output end of the AC input control circuit, the second end of the first switch tube is connected with the first end of the second switch tube, and the third end of the first switch tube is used for connecting a driving signal;

[0030] The second end of the second switch tube is connected with the second end of the first capacitor, and the third end of the second switch tube is used for connecting a driving signal.

[0031] In one of the embodiments, the first pole in the second end of the DC input control circuit is connected with the first end of the first capacitor, and the second pole in the second end of the DC input control circuit is connected with the second end of the second capacitor.

[0032] In one of the embodiments, the AC-DC dual-input circuit further comprises a DC-DC conversion circuit, wherein;

[0033] The first end of the DC-DC conversion circuit is connected with a DC bus, and the second end of the DC-DC conversion circuit is used for connecting a DC electrical equipment.

[0034] In the second aspect, a power supply module is provided, comprising the AC-DC dual-input circuit provided in the first aspect.

[0035] The above AC-DC dual-input circuit and power module, wherein the AC-DC dual-input circuit comprises an AC input control circuit, a DC input control circuit, an AC-DC conversion circuit and a DC bus, wherein a first end of the AC input control circuit is configured to be connected to an AC input power signal, a second end of the AC input control circuit is connected to a first end of the AC-DC conversion circuit, a first end of the DC input control circuit is configured to be connected to a DC input power signal, a second end of the DC input control circuit is connected to a second end of the AC-DC conversion circuit, and the second end of the AC-DC conversion circuit is connected to the DC bus; in this way, the above AC-DC dual-input circuit has two input ports, i.e., the first end of the DC input control circuit and the first end of the AC input control circuit; according to a specific application scenario, the power supply source of the DC bus is switched according to the specific scenario; for example, in the case where an AC input source exists, the DC input source is disconnected through the DC input control circuit, and the DC bus is powered by the AC input source; in the case where the AC input source cannot normally supply power or the AC input source does not exist, the AC input source is disconnected through the AC input control circuit, and the DC target is powered by the DC input source; automatic switching of different input sources can be realized, uninterrupted power supply to the DC power equipment can be realized, and the situation of power interruption of the DC power equipment caused by the way of manually closing the DC power equipment and switching the input port in the related art when switching the DC input and the AC input can be avoided. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the drawings needed to be used in the embodiments or the related art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0037] Figure 1 The structural block diagram of the AC-DC dual-input circuit in an embodiment;

[0038] Figure 2 The structural block diagram of the AC-DC dual-input circuit in another embodiment;

[0039] Figure 3 The circuit topological structure diagram of the AC-DC dual-input circuit in another embodiment.

[0040] Explanation of reference signs:

[0041] 100, AC input control circuit; 200, DC input control circuit; 110, first relay; 120, AC pre-charge circuit; 121, second relay; 210, third relay; 220, DC pre-charge circuit; 221, fourth relay; 300, AC-DC conversion circuit; 400, DC bus. DETAILED DESCRIPTION

[0042] In order to make the above objectives, characteristics and advantages of the present application more apparent, specific embodiments of the present application will be described in detail below with reference to the drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of ways other than those specifically described herein, and it is to be understood that the present application is not limited in its application to the particulars set forth in the following description. It is to be understood that the drawings are not necessarily to scale and that, unless otherwise indicated, the drawings are merely intended to schematically represent the general structure of the application. It should also be understood that, unless otherwise indicated herein, the drawings are merely schematic representations, unless otherwise specified, and some of the drawings can have been exaggerated to more clearly and fully illustrate the present application. The drawings can not be to scale. Like components can have the same reference numbers.

[0043] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0044] In addition, the terms "first", "second", "third", etc. are used only for descriptive purposes and should not be construed as indicating or implying relative importance or implying the number of the technical features indicated. Therefore, the features defined with "first", "second", etc. can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0045] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0046] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0047] It should be noted that when an element is referred to as "fixed to" or "provided on" another element, it can be directly on another element or there can be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to another element or there can be a middle element. The terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used herein are for illustrative purposes only and are not the only embodiment.

[0048] In an exemplary embodiment, please refer to Figure 1 , the provided AC-DC dual input circuit includes AC input control circuit 100, DC input control circuit, AC-DC conversion circuit 300 and DC bus 400, wherein the first end of AC input control circuit 100 is used to connect AC input electrical signal, the second end of AC input control circuit 100 is connected with the first end of AC-DC conversion circuit 300; the first end of DC input control circuit 200 is used to connect DC input electrical signal, the second end of DC input control circuit 200 is connected with the second end of AC-DC conversion circuit 300; the second end of AC-DC conversion circuit 300 is connected with DC bus 400.

[0049] In the case that the AC input source can normally provide AC input electrical signal, for example, in the case that the power grid can normally supply power, the AC input control circuit 100 transmits the AC input electrical signal to the AC-DC conversion circuit 300; the AC-DC conversion circuit 300 converts the AC input electrical signal into DC and transmits it to the DC bus 400, at this time, the DC input control circuit 200 disconnects the connection between the DC bus 400 and the DC input electrical signal. For example, Figure 1 U, V and W in the formula (1) represent three phases of AC electrical signal respectively, U bus + and U bus - represent the positive and negative poles of DC bus 400 respectively.

[0050] In the case that the AC input source cannot normally provide the AC input electrical signal and there is a DC input, for example, in the case of a power grid outage, the AC input control circuit 100 disconnects the connection between the AC input electrical signal and the AC-DC conversion circuit 300, and cuts off the AC input, preventing the AC input source from directly flowing into the AC-DC dual input circuit when it is restored; the DC input control circuit 200 connects the DC bus 400 to the second end of the AC-DC conversion circuit 300, and uses the DC input source to supply the DC bus 400 with a DC input electrical signal; and the DC input source is used to supply power to the DC bus 400. For example, Figure 1 U dc + and U dc - represent the positive and negative poles of the DC input electrical signal, respectively.

[0051] When the AC input source can normally provide the AC input electrical signal and the DC input source can also normally provide the AC input electrical signal, the AC-DC dual input circuit can select one of the AC input source or the DC input source to supply power to the DC bus 400 based on specific application requirements, through the control of the AC input control circuit 100 and the DC input control circuit 200.

[0052] In one possible implementation, the AC input control circuit 100 includes a first relay 110, wherein the connection and disconnection between the AC-DC conversion circuit 300 and the AC input electrical signal are controlled by the closing and opening of the first relay 110.

[0053] In one possible implementation, the DC input control circuit 200 includes a third relay 210, wherein the connection and disconnection between the DC bus 400 and the DC input electrical signal are controlled by the closing and opening of the third relay 210.

[0054] The AC-DC dual input circuit provided by the above embodiment comprises an AC input control circuit 100, a DC input control circuit 200, an AC-DC conversion circuit 300, and a DC bus 400. The first end of the AC input control circuit 100 is used to connect an AC input power signal. The second end of the AC input control circuit 100 is connected to the first end of the AC-DC conversion circuit 300. The first end of the DC input control circuit 200 is used to connect a DC input power signal. The second end of the DC input control circuit 200 is connected to the second end of the AC-DC conversion circuit 300. The second end of the AC-DC conversion circuit 300 is connected to the DC bus 400. In this way, the AC-DC dual input circuit has two input ports, i.e., the first end of the DC input control circuit 200 and the first end of the AC input control circuit 100. According to the specific application scenario, the power supply source of the DC bus 400 is switched according to the specific scenario. For example, in the case where an AC input source exists, the DC input source is disconnected through the DC input control circuit 200, and the DC bus 400 is powered by the AC input source. In the case where the AC input source cannot normally supply power or the AC input source does not exist, the AC input source is disconnected through the AC input control circuit 100, and the DC target is powered by the DC input source. The automatic switching of different input sources can be realized, the uninterrupted power supply to the DC power consumption device can be realized, and the situation that the DC power consumption device is interrupted due to the manual shutdown of the DC power consumption device and the switching of the input port in the related art can be avoided.

[0055] For example, the DC power consumption device can be a DC load device or a DC energy storage device.

[0056] Further, the AC-DC dual input circuit provided by the above embodiment has two relatively independent ports, i.e., the DC input port and the AC input port. The AC input power and the DC input power can be unaffected by the circuit and the power device, so that the DC input source and the AC input source can both achieve the beneficial effect of full output power output. In the related art, a single input port is used to compatible AC input and DC input. Since the circuit and the device are designed for AC input priority, the DC input part cannot fully utilize all circuits or devices, resulting in the problem that the DC input power cannot reach the rated power of the AC input.

[0057] In an example embodiment, please refer to Figure 2 The AC input control circuit 100 comprises a first relay 110 and an AC precharge circuit 120. The first end of the first relay 110 is used to connect an AC input power signal. The second end of the first relay 110 is connected to the first end of the AC precharge circuit 120. The second end of the AC precharge circuit 120 is used to connect the first end of the AC-DC conversion circuit 300.

[0058] In the case that the AC input source can normally provide the AC input signal, the first relay 110 is closed to connect the AC input signal and the AC pre-charge circuit 120. In a possible implementation, the first relay 110 includes three single-pole single-throw switches corresponding to three phase circuits of the AC input source. For example, the first relay 110 includes a switch S1, a switch S2 and a switch S3, where the switch S1 is connected to the U phase circuit of the AC input source, the switch S2 is connected to the V phase circuit of the AC input source, and the switch S3 is connected to the W phase circuit of the AC input source. The switches S1, S2 and S3 are single-pole single-throw contact switches inside the first relay 110. For example, the first relay 110 is implemented by a dual-in-line relay. For example, the first relay 110 further includes resistors connected in parallel with the three contact switches to limit the arc energy generated by the contact due to high current or voltage when the first relay 110 is switched from open to closed. Figure 3

[0059] The AC pre-charge circuit 120 is configured to transmit the AC input signal to the AC-DC conversion circuit through a pre-charge resistor provided in the AC pre-charge circuit 120 when the first relay 110 is closed, so that the current at the DC bus 400 gradually increases, thereby avoiding damage to the DC load connected to the DC bus 400 due to excessive instantaneous inrush current when switching to the AC input source.

[0060] In a possible implementation of the present embodiment, the AC pre-charge circuit 120 includes a second relay 121 and three single-phase pre-charge resistors. The second relay 121 includes three second double-throw switches, each corresponding to a single-phase pre-charge circuit. The first end of the second double-throw switch is connected to the second end of the first relay 110, the second end of the second double-throw switch is connected to the first end of the corresponding single-phase pre-charge resistor, and the third end of the second double-throw switch is connected to the first end of the AC-DC conversion circuit 300. The second end of the single-phase pre-charge resistor is connected to the first end of the AC-DC conversion circuit 300.

[0061] For example, the second relay 121 includes a switch S4, a switch S5 and a switch S6, where the switch S4 is connected to the U phase circuit of the AC input source, the switch S5 is connected to the V phase circuit of the AC input source, and the switch S6 is connected to the W phase circuit of the AC input source. The switches S4, S5 and S6 are double-throw contact switches inside the second relay 121. For example, the second relay 121 is implemented by a double-in-line relay. For example, the second relay 121 further includes resistors connected in parallel with the three contact switches to limit the arc energy generated by the contact due to high current or voltage when the second relay 121 is switched from open to closed. Figure 3 ​, three double-throw switches are switch S4, switch S5 and switch S6, and three single-phase pre-charging resistors are resistor R1, resistor R2 and resistor R3, wherein the common contact of switch S4 is connected with switch S1, the normally closed contact of switch S4 is connected with resistor R1, and the normally open contact of switch S4 is connected with the U-phase input in the first end of AC-DC conversion circuit 300; the common contact of switch S5 is connected with switch S2, the normally closed contact of switch S5 is connected with resistor R2, and the normally open contact of switch S5 is connected with the V-phase input in the first end of AC-DC conversion circuit; the common contact of switch S6 is connected with switch S3, the normally closed contact of switch S6 is connected with resistor R3, and the normally open contact of switch S6 is connected with the W-phase input in the first end of AC-DC conversion circuit 300. In the case that there is an AC input source, switch S1, switch S2 and switch S3 are closed, the normally closed contacts of switch S4, switch S5 and switch S6 are closed, and the normally open contacts are disconnected, that is, the single-phase pre-charging resistors are connected, and the current input by the AC input source passes through the pre-charging resistors and AC-DC conversion circuit 300 to pre-charge DC bus 400; for example, when the voltage value U bus of DC bus 400 is detected to be less than a preset voltage value, the normally closed contacts of switch S4, switch S5 and switch S6 are disconnected, and the normally open contacts are connected, that is, the single-phase pre-charging resistors are disconnected, and AC-DC conversion circuit 300 directly converts the AC signal output by the AC input source into DC and transmits it to DC bus 400. For example, the preset difference is 25V to 35V, and optionally, the preset difference is 30V. uv The difference between the uncontrolled rectification voltage of the AC input voltage and the AC voltage of the AC input source (wherein U uv refers to the input line voltage between the U-phase and the V-phase) is less than a preset difference. For example, the normally closed contacts of switch S4, switch S5 and switch S6 are disconnected, and the normally open contacts are connected, that is, the single-phase pre-charging resistors are disconnected, and AC-DC conversion circuit 300 directly converts the AC signal output by the AC input source into DC and transmits it to DC bus 400. For example, the preset difference is 25V to 35V, and optionally, the preset difference is 30V.

[0062] For example, the second relay 121 including three double-throw switches can be a three-pole double-throw relay. For example, the second relay 121 further includes a resistor connected in parallel with the three double-throw switches, which is used to limit the arc energy generated by the contacts of the second relay 121 when switching between the open and closed states due to high current or voltage.

[0063] In another possible implementation in the embodiment, the AC pre-charging circuit 120 includes three AC pre-charging sub-circuits, each corresponding to a phase circuit of the AC input source. Each AC pre-charging sub-circuit includes a single-phase pre-charging resistor and a single-phase switch connected in parallel; in the case that there is an AC input signal, each single-phase switch is disconnected, so that the AC input signal is connected to the first end of AC-DC conversion circuit 300 through each single-phase pre-charging resistor, and when the voltage value U bus of DC bus 400 is detected to be less than a preset voltage value, the normally closed contacts of switch S4, switch S5 and switch S6 are disconnected, and the normally open contacts are connected, that is, the single-phase pre-charging resistors are disconnected, and AC-DC conversion circuit 300 directly converts the AC signal output by the AC input source into DC and transmits it to DC bus 400. For example, the preset difference is 25V to 35V, and optionally, the preset difference is 30V. If the difference between them is less than the preset difference, control each single-phase switch to close and short-circuit each single-phase pre-charge resistor, that is, the single-phase pre-charge resistor is disconnected, and the AC-DC conversion circuit 300 directly converts the AC signal output from the AC input source into DC and transmits it to the DC bus 400.

[0064] The AC / DC dual-input circuit provided in the above embodiment includes an AC input control circuit 100 comprising a first relay 110 and an AC pre-charging circuit 120. When it is detected that the DC bus 400 is being powered by an AC input source, the first relay 110 is closed, and the AC pre-charging circuit 120 is used to pre-charge the DC bus 400. This avoids excessive current surges that could cause damage to DC electrical equipment when directly switching to an AC input source. The AC / DC dual-input circuit provided in this embodiment ensures that when the DC electrical equipment is initially connected to an AC input source, a large voltage difference between the DC bus 400 and the AC input source during AC input signal switching can be avoided, thus preventing damage to the DC electrical equipment. The AC / DC dual-input circuit described above can improve the operational reliability of DC electrical equipment.

[0065] In an exemplary embodiment, the DC input control circuit 200 includes a third relay 210 and a DC pre-charge circuit 220, wherein the first terminal of the third relay 210 is used to connect to the DC input electrical signal, and the second terminal of the third relay 210 is connected to the first terminal of the DC pre-charge circuit 220; the second terminal of the DC pre-charge circuit 220 is used to connect to the second terminal of the AC-DC conversion circuit 300.

[0066] Specifically, when there is a DC input but no AC input, the third relay 210 is closed to connect the DC input electrical signal and the DC pre-charge circuit 220; when there is an AC input, the third relay 210 is closed to disconnect the connection between the DC input source and the DC bus 400.

[0067] In one possible implementation, the third relay 210 includes two single-pole single-throw switches, corresponding to the positive and negative terminals of the DC input source, respectively. For an example, please refer to... Figure 3 The third relay 210 includes switches S7 and S8, wherein switch S7 is connected to the positive terminal of the DC input source, and switch S8 is connected to the negative terminal of the DC input source. Switches S7 and S8 are single-pole single-throw contact switches within the third relay 210. Exemplarily, the third relay 210 is implemented using a dual-in-line relay. Exemplarily, the first relay 110 also includes a resistor connected in parallel with the three contact switches to limit the arcing energy that may be generated at the contacts due to high current or voltage when the third relay 210 switches between open and closed states.

[0068] The DC pre-charging circuit 220 is configured to transmit the DC input signal to the DC bus 400 through a pre-charging resistor arranged in the DC pre-charging circuit 220 when the third relay 210 is closed, so that the current at the DC bus 400 slowly increases, thereby avoiding damage to the DC electrical equipment connected to the DC bus 400 due to an excessively large instantaneous impact current when switching to the DC input source.

[0069] In a possible implementation of the embodiment, the DC pre-charging circuit 220 includes a fourth relay 221 and two DC pre-charging resistors. The fourth relay 221 includes two fourth double-pole switches, each of which corresponds to a DC pre-charging circuit 220. The first end of each fourth double-pole switch is connected to the second end of the third relay 210, the second end of each fourth double-pole switch is connected to the first end of a corresponding DC pre-charging resistor, and the third end of each fourth double-pole switch is connected to the second end of the AC-DC conversion circuit 300. The second end of each DC pre-charging resistor is connected to the second end of the AC-DC conversion circuit 300.

[0070] For example, Figure 3 The two fourth double-pole switches are switch S9 and switch S10, and the two DC pre-charging resistors are resistor R4 and resistor R5. The common contact of the switch S9 is connected to the switch S7, the normally closed contact of the switch S9 is connected to the resistor R4, and the normally open contact of the switch S9 is connected to the positive pole of the DC bus 400. The common contact of the switch S10 is connected to the switch S5, the normally closed contact of the switch S10 is connected to the resistor R8, and the normally open contact of the switch S5 is connected to the negative pole of the DC bus 400.

[0071] When the DC input source is needed, the switch S7 and the switch S8 are closed, the normally closed contacts of the switch S9 and the switch S10 are closed, and the normally open contacts are disconnected, that is, the DC pre-charging resistors are connected, and the current input by the DC input source pre-charges the DC bus 400 through the DC pre-charging resistors. For example, when it is detected that the voltage value U bus of the DC bus 400 is less than the input voltage U dc of the DC input source, the normally closed contacts of the switch S9 and the switch S10 are disconnected, and the normally open contacts are closed, that is, the DC pre-charging resistors are disconnected, and the DC input source directly supplies power to the DC bus 400. For example, the preset difference is 25V to 35V, and optionally, the preset difference is 30V.

[0072] In another possible implementation of the embodiment, the DC pre-charging circuit 220 includes two DC pre-charging sub-circuits, each of which corresponds to the positive pole and the negative pole of the DC input source. Each DC pre-charging sub-circuit includes a unipolar pre-charging resistor and a unipolar switch connected in parallel. The control logic of the DC pre-charging sub-circuit is similar to that of the AC pre-charging sub-circuit, and thus is not described herein.

[0073] The AC / DC dual input circuit provided by the above embodiment, wherein the AC input control circuit 100 comprises a third relay 210 and a DC precharge circuit 220, in the case of detecting that the DC bus 400 is powered by the DC input source, the third relay 210 is closed, the input source of the DC bus 400 is switched to the DC input source, and the DC precharge circuit 220 is used to precharge the DC bus 400, avoiding the case that the current impact is too large when directly switching to the DC input source, causing the loss of the DC power equipment. The AC / DC dual input circuit provided by the embodiment can ensure that when the DC power equipment is initially connected to the DC input source, the voltage difference between the DC input signal and the DC bus 400 is large, which can cause damage to the DC power equipment. The AC / DC dual input circuit can improve the operation reliability of the DC power equipment.

[0074] In one exemplary embodiment, the AC / DC conversion circuit 300 comprises: a first capacitor C1, a second capacitor C2, and three single-phase conversion circuits; wherein the first end of the single-phase conversion circuit is connected to the corresponding phase output end of the AC input control circuit 100, the second end of the single-phase conversion circuit is connected to the first end of the first capacitor C1, the third end of the single-phase conversion circuit is connected to the second end of the first capacitor, and the fourth end of the single-phase conversion circuit is connected to the second end of the second capacitor C2; the first end of the first capacitor C1 is connected to the first end of the DC bus 400; the first end of the second capacitor C2 is connected to the second end of the first capacitor C1; and the second end of the second capacitor C2 is connected to the second end of the DC bus 400.

[0075] Among them, the three single-phase conversion circuits correspond to the U-phase circuit, the V-phase circuit and the W-phase circuit of the AC input source respectively.

[0076] In a possible implementation, the single-phase conversion circuit comprises a first diode, a second diode, a first switch tube and a second switch tube, wherein the anode of the first diode is connected to the corresponding phase output end of the AC input control circuit 100, and the cathode of the first diode is connected to the first end of the first capacitor; the anode of the second diode is connected to the second end of the second capacitor, and the cathode of the second diode is connected to the corresponding phase output end of the AC input control circuit 100; the first end of the first switch tube is connected to the corresponding phase output end of the AC input control circuit 100, the second end of the first switch tube is connected to the first end of the second switch tube, and the third end of the first switch tube is used to connect a driving signal; the second end of the second switch tube is connected to the second end of the first capacitor, and the third end of the second switch tube is used to connect a driving signal. The driving signal is a pulse width modulation (PWM) signal.

[0077] For example, refer to Figure 3The single-phase conversion circuit corresponding to the U-phase circuit comprises a diode D1, a diode D2, a switch tube Q1 and a switch tube Q2, wherein the switch tube Q1 and the switch tube Q6 are active driving switch tubes and are controlled based on a driving signal PWM1, wherein the positive electrode of the diode D1, the negative electrode of the diode D2 and the first end of the switch tube Q1 are connected with the U-phase output end of the alternating current input control circuit 100, the negative electrode of the diode D1 is connected with the positive electrode of the first capacitor C1, the positive electrode of the diode D2 is connected with the negative electrode of the second capacitor, the second end of the switch tube Q1 is connected with the first end of the switch tube Q2, the second end of the switch tube Q2 is connected with the negative electrode of the first capacitor C1, and the third ends of the switch tube Q1 and the switch tube Q2 are used for connecting the driving signal PWM1.

[0078] For example, refer to Figure 3 The single-phase conversion circuit corresponding to the V-phase circuit comprises a diode D3, a diode D4, a switch tube Q3 and a switch tube Q4, wherein the switch tube Q3 and the switch tube Q4 are active driving switch tubes and are controlled based on a driving signal PWM2, wherein the positive electrode of the diode D3, the negative electrode of the diode D4 and the first end of the switch tube Q3 are connected with the V-phase output end of the alternating current input control circuit 100, the negative electrode of the diode D3 is connected with the positive electrode of the first capacitor C1, the positive electrode of the diode D4 is connected with the negative electrode of the second capacitor, the second end of the switch tube Q3 is connected with the first end of the switch tube Q4, the second end of the switch tube Q4 is connected with the negative electrode of the first capacitor C1, and the third ends of the switch tube Q3 and the switch tube Q4 are used for connecting the driving signal PWM3.

[0079] For example, refer to Figure 3 The single-phase conversion circuit corresponding to the W-phase circuit comprises a diode D5, a diode D6, a switch tube Q5 and a switch tube Q6, wherein the switch tube Q5 and the switch tube Q6 are active driving switch tubes and are controlled based on a driving signal PWM3, wherein the positive electrode of the diode D5, the negative electrode of the diode D6 and the first end of the switch tube Q5 are connected with the W-phase output end of the alternating current input control circuit 100, the negative electrode of the diode D5 is connected with the positive electrode of the first capacitor C1, the positive electrode of the diode D6 is connected with the negative electrode of the second capacitor, the second end of the switch tube Q5 is connected with the first end of the switch tube Q6, the second end of the switch tube Q6 is connected with the negative electrode of the first capacitor C1, and the third ends of the switch tube Q5 and the switch tube Q6 are used for connecting the driving signal PWM3.

[0080] In a possible implementation, the first pole in the second end of the direct current input control circuit 200 is connected with the first end of the first capacitor C1, and the second pole in the second end of the direct current input control circuit 200 is connected with the second end of the second capacitor.

[0081] For example, refer to Figure 3The positive pole in the second end of the direct current input control circuit 200 is connected with the positive pole of the first capacitor C1, and the negative pole in the second end of the direct current input control circuit 200 is connected with the negative pole of the second capacitor.

[0082] In an exemplary embodiment, the AC-DC dual input circuit further comprises a direct current-direct current conversion circuit, wherein a first end of the direct current-direct current conversion circuit is connected to the direct current bus 400, and a second end of the direct current-direct current conversion circuit is used to connect the direct current electrical equipment.

[0083] In this way, the direct current input control circuit 200 is connected between the AC-DC conversion circuit 300 and the direct current-direct current conversion circuit. In the case of the energy storage device with the direct current input source, the direct current input electrical signal can pass through the later-stage isolated direct current-direct current conversion circuit to supply power to the direct current electrical equipment, thereby avoiding the problem of needing to separately set a single-stage direct current-direct current conversion circuit for the direct current input source in the related art. The AC-DC dual input circuit provided in the embodiment can reduce the hardware cost of the power supply module.

[0084] In an exemplary embodiment, please refer to Figure 3 The AC-DC dual input circuit comprises: an AC input control circuit 100, a direct current input control circuit 200, an AC-DC conversion circuit 300, and a direct current bus 400; wherein,

[0085] The AC input control circuit 100 comprises a first relay 110 and an AC pre-charging circuit 120, wherein a first end of the first relay 110 is used to connect an AC input electrical signal, a second end of the first relay 110 is connected with a first end of the AC pre-charging circuit 120; a second end of the AC pre-charging circuit 120 is used to connect a first end of the AC-DC conversion circuit 300. The AC pre-charging circuit 120 comprises a second relay 121 and three single-phase pre-charging resistors. The second relay 121 comprises three second double-pole switches, each second double-pole switch corresponds to each single-phase pre-charging circuit, wherein a first end of the second double-pole switch is connected with the second end of the first relay 110, a second end of the second double-pole switch is connected with a first end of the corresponding single-phase pre-charging resistor, and a third end of the second double-pole switch is connected with the first end of the AC-DC conversion circuit 300; a second end of the single-phase pre-charging resistor is connected with the first end of the AC-DC conversion circuit 300.

[0086] The direct current input control circuit 200 comprises a third relay 210 and a direct current pre-charging circuit 220, wherein a first end of the third relay 210 is used for connecting a direct current input signal, a second end of the third relay 210 is connected with a first end of the direct current pre-charging circuit 220; a second end of the direct current pre-charging circuit 220 is used for connecting a second end of the alternating current-direct current conversion circuit 300. The direct current pre-charging circuit 220 comprises a fourth relay 221 and two direct current pre-charging resistors, wherein the fourth relay 221 comprises two fourth double-pole switches, each fourth double-pole switch corresponds to each direct current pre-charging circuit 220 respectively, wherein a first end of the fourth double-pole switch is connected with the second end of the third relay 210, a second end of the fourth double-pole switch is connected with a first end of the corresponding direct current pre-charging resistor, a third end of the fourth double-pole switch is connected with the second end of the alternating current-direct current conversion circuit 300; a second end of the direct current pre-charging resistor is connected with the second end of the alternating current-direct current conversion circuit 300.

[0087] The second end of the alternating current-direct current conversion circuit 300 is connected with the direct current bus 400, comprising a first capacitor, a second capacitor and three single-phase conversion circuits; wherein the single-phase conversion circuit comprises a first diode, a second diode, a first switch tube and a second switch tube, wherein a positive electrode of the first diode is connected with a corresponding phase output end of the alternating current input control circuit 100, a negative electrode of the first diode is connected with a first end of the first capacitor; a positive electrode of the second diode is connected with a second end of the second capacitor, a negative electrode of the second diode is connected with a corresponding phase output end of the alternating current input control circuit 100; a first end of the first switch tube is connected with a corresponding phase output end of the alternating current input control circuit 100, a second end of the first switch tube is connected with a first end of the second switch tube, a third end of the first switch tube is used for connecting a driving signal; a second end of the second switch tube is connected with a second end of the first capacitor, a third end of the second switch tube is used for connecting a driving signal.

[0088] The first end of the first capacitor is connected with a first end of the direct current bus 400, the first end of the second capacitor is connected with a second end of the first capacitor, and the second end of the second capacitor is connected with a second end of the direct current bus 400.

[0089] The alternating current-direct current dual input circuit provided by the above embodiment can detect the alternating current input signal (the line voltage U uv between the U phase and the V phase, the line voltage U vw between the V phase and the W phase, or the phase voltage U wu between the W phase and the U phase), the direct current input signal U dc , the direct current bus 400 voltage U busThe input source to be switched and the switching time can be determined. Due to the existence of the single-phase pre-charging resistor and the DC pre-charging resistor, the AC-DC dual-input circuit can realize seamless switching. For example, in the case of power outage and power recovery of the AC power supply, the AC-DC dual-input circuit can realize fast switching, and the problem of damage of the DC power device caused by a large voltage difference between the DC bus 400 and the input source does not need to be considered.

[0090] The AC-DC dual-input circuit provided by the above embodiments can improve the use flexibility of the DC power device, so that the DC power device can adapt to different power supply environments. Whether in a place with AC power or in a special environment with only DC power, the DC power device can work normally, greatly improving the application range and use convenience of the DC power device.

[0091] The AC-DC dual-input circuit provided by the above embodiments enables the power module to have a power backup and emergency support function. When the AC input source fails or is powered off, the power module can be quickly switched to the DC input to ensure continuous operation of the power module, provide reliable emergency power support for important DC power devices or other power systems, and reduce losses caused by power failure.

[0092] The AC-DC dual-input circuit provided by the above embodiments can improve the energy utilization rate of the DC power device and can fully utilize various forms of energy. For example, in some places with both solar power generation (DC power supply) and power supply (AC power supply), the power source can be flexibly selected according to the actual situation, such as preferentially using clean energy, improving energy utilization efficiency, and reducing energy costs.

[0093] The AC-DC dual-input circuit provided by the above embodiments can improve the energy utilization rate of the DC power device and can fully utilize various forms of energy. For example, in some places with both solar power generation (DC power supply) and power supply (AC power supply), the power source can be flexibly selected according to the actual situation, such as preferentially using clean energy, improving energy utilization efficiency, and reducing energy costs.

[0094] The application also provides a power module, which comprises the AC-DC dual-input circuit described in the above embodiments.

[0095] The technical features of the above embodiments can be combined in any way. To make the description concise, all possible combinations of the technical features in the above embodiments are not described, but as long as the combination of the technical features does not exist, it should be considered as the scope of the description.

[0096] The above-described embodiments only express several implementation manners of the utility model, the description is more specific and detailed, but can not therefore be understood as the limitation of the utility model patent range. It should be pointed out that for ordinary skilled person in the art, without departing from the concept of the utility model, several modifications and improvements can be made, which belong to the protection range of the utility model. Therefore, the protection range of the utility model patent should be subject to the appended claims.

Claims

1. An AC / DC dual-input circuit, characterized in that, The AC-DC dual-input circuit comprises an AC input control circuit, a DC input control circuit, an AC-DC conversion circuit and a DC bus, wherein the first end of the AC input control circuit is used for connecting an AC input electrical signal, and the second end of the AC input control circuit is connected with the first end of the AC-DC conversion circuit; the first end of the DC input control circuit is used for connecting a DC input electrical signal, and the second end of the DC input control circuit is connected with the second end of the AC-DC conversion circuit; the second end of the AC-DC conversion circuit is connected with the DC bus.

2. The AC / DC dual input circuit according to claim 1, characterized by The AC input control circuit comprises a first relay and an AC pre-charging circuit, wherein the first end of the first relay is used for connecting the AC input electrical signal, and the second end of the first relay is connected with the first end of the AC pre-charging circuit; the second end of the AC pre-charging circuit is used for connecting the first end of the AC-DC conversion circuit.

3. The AC / DC dual input circuit according to claim 2, characterized by The AC pre-charging circuit comprises a second relay and three single-phase pre-charging resistors, the second relay comprises three second double-pole switches, and each second double-pole switch corresponds to each single-phase pre-charging resistor, wherein the first end of the second double-pole switch is connected with the second end of the first relay, the second end of the second double-pole switch is connected with the first end of the corresponding single-phase pre-charging resistor, and the third end of the second double-pole switch is connected with the first end of the AC-DC conversion circuit; the second end of the single-phase pre-charging resistor is connected with the first end of the AC-DC conversion circuit.

4. The AC / DC dual input circuit according to claim 1, characterized by The DC input control circuit comprises a third relay and a DC pre-charging circuit, wherein the first end of the third relay is used for connecting the DC input electrical signal, and the second end of the third relay is connected with the first end of the DC pre-charging circuit; the second end of the DC pre-charging circuit is used for connecting the second end of the AC-DC conversion circuit.

5. The AC / DC dual input circuit according to claim 4, characterized by The DC pre-charging circuit comprises a fourth relay and two DC pre-charging resistors, wherein the fourth relay comprises two fourth double-pole switches, and each fourth double-pole switch corresponds to each DC pre-charging resistor, wherein the first end of the fourth double-pole switch is connected with the second end of the third relay, the second end of the fourth double-pole switch is connected with the first end of the corresponding DC pre-charging resistor, and the third end of the fourth double-pole switch is connected with the second end of the AC-DC conversion circuit; the second end of the DC pre-charging resistor is connected with the second end of the AC-DC conversion circuit.

6. The AC / DC dual input circuit according to claim 1, wherein The AC-DC conversion circuit comprises a first capacitor, a second capacitor and three single-phase conversion circuits, wherein the first end of the single-phase conversion circuit is connected with the corresponding phase output end of the AC input control circuit, the second end of the single-phase conversion circuit is connected to the first end of the first capacitor, the third end of the single-phase conversion circuit is connected to the second end of the first capacitor, and the fourth end of the single-phase conversion circuit is connected to the second end of the second capacitor; the first end of the first capacitor is connected with the first end of the DC bus; the first end of the second capacitor is connected with the second end of the first capacitor, and the second end of the second capacitor is connected with the second end of the DC bus.

7. The AC / DC dual input circuit according to claim 6, characterized by The single-phase conversion circuit comprises a first diode, a second diode, a first switch tube and a second switch tube, wherein, a positive electrode of the first diode is connected with a corresponding phase output end of the AC input control circuit, and a negative electrode of the first diode is connected with a first end of the first capacitor; a positive electrode of the second diode is connected with a second end of the second capacitor, and a negative electrode of the second diode is connected with a corresponding phase output end of the AC input control circuit; a first end of the first switch tube is connected with a corresponding phase output end of the AC input control circuit, a second end of the first switch tube is connected with a first end of the second switch tube, and a third end of the first switch tube is used for connecting a driving signal; a second end of the second switch tube is connected with a second end of the first capacitor, and a third end of the second switch tube is used for connecting a driving signal.

8. The AC / DC dual input circuit according to claim 6, wherein a first pole in a second end of the DC input control circuit is connected with a first end of the first capacitor, and a second pole in the second end of the DC input control circuit is connected with a second end of the second capacitor.

9. The AC / DC dual input circuit according to claim 1, characterized by The AC-DC dual-input circuit further comprises a DC-DC conversion circuit, wherein; a first end of the DC-DC conversion circuit is connected with the DC bus, and a second end of the DC-DC conversion circuit is used for connecting a DC electrical equipment.

10. A power module, characterized by The power supply module comprises the AC-DC dual-input circuit according to any one of claims 1-9.

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