CN218102977U - Power supply circuit and electronic device - Google Patents

Abstract

The application relates to a power supply circuit and an electronic device. A power supply circuit, comprising: the device comprises an alternating current connection port, an AC/DC conversion circuit, a pre-charging circuit and a control circuit. The AC/DC conversion circuit comprises a main switch unit, a boosting unit and a switch bridge arm unit which are sequentially connected, the pre-charging circuit is connected with the main switch unit and the boosting unit in parallel, when in pre-charging, the pre-charging circuit and a parasitic diode of the switch bridge arm unit form a pre-charging loop between an alternating current source and a direct current bus under the control of the control circuit, and a pre-charging signal can be output through the direct current bus by multiplexing a switch tube of the switch bridge arm unit.

Description

Power supply circuit and electronic device

Technical Field

The application belongs to the technical field of electronic circuits, and particularly relates to a power supply circuit and electronic equipment.

Background

In an AC/DC conversion circuit having an AC connection port, a Power Factor Correction (PFC) boost technique is basically used, and an energy storage device connected to a DC bus is provided at an output terminal of the PFC circuit to store electric energy and stably output a DC voltage. In order to ensure the normal operation of the circuit, the energy storage device is usually pre-charged, so that the impact of an overlarge charging signal on the energy storage device is avoided.

However, when the energy storage device is precharged, a precharge relay, a boost bridge, a precharge resistor and the like need to be configured, which not only increases the space requirement for the circuit board, but also increases the implementation cost.

SUMMERY OF THE UTILITY MODEL

The application aims to provide a power supply circuit and electronic equipment, and aims to solve the problem that the traditional power supply circuit is high in space requirement and implementation cost of a circuit board.

A first aspect of an embodiment of the present application provides a power supply circuit, including: an AC connection port; an AC/DC conversion circuit configured with a main switch unit connected with the AC connection port to form a first node, a boost unit, and a switch bridge arm unit, the main switch unit being connected in series with the boost unit; the boosting unit is connected with the switch bridge arm unit to form a second node, and the output end of the switch bridge arm unit is used for being connected with a direct current bus; the switching bridge arm unit comprises N pairs of switching tubes, each switching tube is provided with a parasitic diode, and N is a positive integer greater than or equal to 2; a precharge circuit connected between the first node and the second node, the precharge circuit being configured with a precharge switch unit and a precharge resistance unit; and the control circuit is connected with the main switch unit, the switch bridge arm unit and the pre-charging switch unit, and is configured to switch on the pre-charging switch unit, switch off the main switch unit and switch off a switch tube in the switch bridge arm unit when an alternating current source is connected to the alternating current connection port, so that the alternating current source outputs a pre-charging signal after passing through the pre-charging circuit and a parasitic diode of the switch bridge arm unit.

In one embodiment, the pre-charging resistor unit includes a current-limiting resistor; and the first end of the current-limiting resistor is connected with the pre-charging switch unit, and the second end of the current-limiting resistor is connected with the second node.

In one embodiment, the boosting unit includes an inductor; and the first end of the inductor is connected with the main switch unit, and the second end of the inductor is connected with the switch bridge arm unit to form the second node.

In one embodiment, the voltage boosting circuit further comprises a filtering unit, wherein a first end of the filtering unit is connected between the main switch unit and the voltage boosting unit; and the second end of the filtering unit is connected with the alternating current connection port.

In one embodiment, the filter unit includes a capacitor, a first end of the capacitor is connected to a first end of the inductor, and a second end of the capacitor is connected to the ac connection port.

In one embodiment, the bridge arm switching circuit further comprises a DC/DC conversion circuit, wherein the DC/DC conversion circuit is connected with the output end of the switch bridge arm unit through the direct current bus; the DC/DC conversion circuit is used for converting the direct current on the direct current bus into direct current with preset voltage and outputting the direct current; the control circuit is further used for controlling the DC/DC conversion circuit to stop working when the pre-charging switch unit is controlled to be conducted.

In an embodiment, the dc bus includes a bus capacitor, a first end of the bus capacitor is connected to the positive output end of the switch bridge arm unit, and a second end of the bus capacitor is connected to the negative output end of the switch bridge arm unit.

In one embodiment, the control circuit further includes a detection unit, where the detection unit is configured to detect a voltage on the dc bus and transmit a corresponding detection voltage to the control circuit, and the control circuit is further configured to control the pre-charge switch unit to be turned on when the ac connection port is connected to the ac source, and control the pre-charge switch unit to be turned off and control the main switch unit to be turned on when the detection voltage reaches a preset voltage.

In one embodiment, the switch bridge arm unit comprises a first switch tube, a second switch tube, a third switch tube and a fourth switch tube; a first conduction end of the first switch tube is connected with a first end of the bus capacitor, and a second conduction end of the first switch tube is connected with the second node; the first conduction end of the second switch tube is connected with the second conduction end of the first switch tube, and the second conduction end of the second switch tube is connected with the second end of the bus capacitor; the first conducting end of the third switching tube is connected with the first end of the bus capacitor, and the second conducting end of the third switching tube is connected with the negative electrode of the alternating current connection port; and a first conduction end of the fourth switching tube is connected with a second conduction end of the third switching tube, and a second conduction end of the fourth switching tube is connected with a second end of the bus capacitor.

A second aspect of the embodiments of the present application provides an electronic device, including the power supply circuit as described above.

The embodiment of the application provides a power supply circuit and electronic equipment, wherein, a power supply circuit includes: the device comprises an alternating current connection port, an AC/DC conversion circuit, a pre-charging circuit and a control circuit. The AC/DC conversion circuit is configured with a main switch unit, a boosting unit and a switch bridge arm unit, the main switch unit is connected with the AC connection port to form a first node, and the main switch unit is connected with the boosting unit in series; the boosting unit is connected with the switch bridge arm unit to form a second node, and the output end of the switch bridge arm unit is used for being connected with the direct current bus; a precharge circuit connected between the first node and the second node, the precharge circuit being configured with a precharge switch unit and a precharge resistance unit; the control circuit is connected with the main switch unit, the switch bridge arm unit and the pre-charging switch unit, and is configured to conduct the pre-charging switch unit and disconnect the main switch unit and the switch tubes in the switch bridge arm unit when an alternating current source is connected to the alternating current connection port, so that the alternating current source outputs pre-charging signals after passing through the pre-charging circuit and the parasitic diodes of the switch bridge arm unit, the multiplexing of the switch tubes of the switch bridge arm unit is realized, the pre-charging signals can be output through a direct current bus, other electronic devices are not required to be additionally added, and the space requirement and the implementation cost of a circuit board are reduced.

Drawings

Fig. 1 is a schematic structural diagram of a power supply circuit provided in an embodiment of the present application;

fig. 2 is a circuit schematic diagram of a power supply circuit provided in an embodiment of the present application;

fig. 3 is a schematic structural diagram of a power supply circuit according to another embodiment of the present application;

FIG. 4 is a circuit diagram of a power supply circuit according to another embodiment of the present application;

FIG. 5 is a schematic diagram illustrating a connection between a detection unit and a DC/DC conversion circuit according to another embodiment of the present application;

fig. 6 is a schematic structural diagram of an electronic device according to an embodiment of the present application;

fig. 7 is a schematic structural diagram of an electronic device according to another embodiment of the present application.

The drawings described above illustrate: 100. a power supply circuit; 200. an AC connection port; 300. an AC/DC conversion circuit; 310. a main switch unit; 320. a boosting unit; 330. switching on and off the bridge arm unit; 340. a filtering unit; 400. a pre-charge circuit; 410. a pre-charge switch unit; 420. a pre-charge resistance unit; 500. a control circuit; 600. a detection unit; 710. a direct current bus; 720. a DC/DC conversion circuit; 800. an alternating current source; 900. An electronic device; 910. an energy storage unit; 920. and an electricity utilization unit.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of and not restrictive on the broad application.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may be explicitly or implicitly configured with one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

Fig. 1 shows a schematic structural diagram of a power supply circuit provided in an embodiment of the present application, and for convenience of description, only parts related to the embodiment are shown, which are detailed as follows:

a power supply circuit 100 comprising: an AC connection port 200, an AC/DC conversion circuit 300, a pre-charge circuit 400 and a control circuit 500.

The ac connection port 200 is used to access the ac source 800. The AC/DC conversion circuit 300 is configured with a main switch unit 310, a boost unit 320, and a switch bridge arm unit 330, where the main switch unit 310 is connected to the AC connection port 200 to form a first node P1, the main switch unit 310 is connected to the boost unit 320 in series, the boost unit 320 is connected to the switch bridge arm unit 330 to form a second node P2, and an output end of the switch bridge arm unit 330 is connected to the DC bus 710. The switching leg unit 330 includes N pairs of switching tubes, each of which has a parasitic diode, where N is a positive integer greater than or equal to 2. The precharge circuit 400 is connected between a first node P1 and a second node P2, and the precharge circuit 400 is configured with a precharge switch unit 410 and a precharge resistor unit 420. The control circuit 500 is connected to the main switch unit 310, the switch bridge arm unit 330 and the pre-charge switch unit 410, and when the ac connection port 200 is connected to the ac source 800, the control circuit 500 is configured to turn on the pre-charge switch unit 410 and turn off the switch tubes in the main switch unit 310 and the switch bridge arm unit 330, so that the ac source 800 outputs a pre-charge signal through the parasitic diodes of the pre-charge circuit 400 and the switch bridge arm unit 330.

In fig. 1, control circuit 500 is connected to main switch unit 310, switch leg unit 330, and pre-charge switch unit 410, respectively, so that control circuit 500 can control on/off of main switch unit 310 and pre-charge switch unit 410, and on/off of switch leg unit 330, respectively.

As shown in fig. 1, when control circuit 500 controls precharge switch unit 410 to be on, main switch unit 310 to be off, and the switch tubes in switch arm unit 330 to be off, a precharge circuit is formed between ac source 800 and dc bus 710. That is, the parasitic diodes of the switching tubes in the ac connection port 200, the precharge switch unit 410, the precharge resistor unit 420, and the switch arm unit 330 form a precharge circuit between the ac source 800 and the dc bus 710, so that the ac source 800 can output a precharge signal through the dc bus 710 after passing through the parasitic diodes of the precharge circuit 400 and the switch arm unit 330.

In some embodiments, the control circuit 500 may be further configured to, after the duration of the precharge signal output by the ac source 800 via the precharge circuit 400 and the parasitic diode of the switch leg unit 330 is greater than a preset duration, turn off the precharge switch unit 410 and turn on the main switch unit 310 and turn on the switch tubes in the switch leg unit 330, so that the ac source 800 outputs the charging signal via the voltage boost unit 320 and the switch leg unit 330.

In practical applications, the dc bus 710 is used to connect an energy storage device, and the ac source 800 outputs a pre-charge signal after passing through the pre-charge circuit 400 and the parasitic diode of the switching arm unit 330, and the pre-charge signal pre-charges the energy storage device through the dc bus 710.

For example, in a specific implementation, the control circuit 500 may be configured with a sampling unit, which is used to sample the electrical signal of the ac connection port 200, and further determine whether the ac connection port 200 is connected to the ac source 800.

For example, the sampling unit samples an electrical signal of the ac connection port 200 and outputs the sampled signal to the control circuit 500, and the control circuit 500 determines, according to the sampled signal, that the ac connection port 200 is connected to the ac source 800, and further controls the pre-charge switch unit 410 to be turned on, and at the same time controls the main switch unit 310 to be turned off, and controls the switch tubes in the switch arm unit 330 to be turned off, so that the ac source 800 outputs a pre-charge signal after passing through the pre-charge circuit 400 and the parasitic diodes of the switch arm unit 330, and the pre-charge energy storage device connected to the dc bus 710 can be pre-charged.

In all embodiments of the present application, the power supply circuit 100 is connected to the ac source 800 through the ac connection port 200, and performs ac-dc conversion on the ac power provided by the ac source 800, so as to pre-charge the pre-charged energy storage device connected to the dc bus 710.

For example, the ac source 800 may be a utility power, and accordingly, the ac connection port 200 is a port for connecting a utility power.

For another example, the ac source 800 may also be another power circuit that outputs ac power, and accordingly, the ac connection port 200 is a connection port corresponding to an output port of the power circuit.

It is understood that after pre-charging the pre-charged energy storage device connected to the DC bus 710, a large current power supply or a large voltage power supply can be realized through the AC/DC conversion circuit 300, i.e., a normal power supply is performed through the AC/DC conversion circuit 300 and the DC bus 710.

In a specific implementation, different ac connection ports 200 may be selected according to the type of the ac source 800 to implement access to the ac source 800, which is not described herein again.

Fig. 2 shows a circuit schematic of the power supply circuit 100. As shown in fig. 2, in the present embodiment, the pre-charged energy storage device connected to the dc bus 710 includes a bus capacitor C1, and the bus capacitor C1 is also connected to the output end of the switching arm unit 330. Specifically, the bus capacitor C1 is connected between the positive and negative poles of the dc bus 710, the first end of the bus capacitor C1 and the positive pole of the dc bus 710 are both connected to the positive output terminal OUT + of the switch bridge arm unit 330, and the second end of the bus capacitor C1 and the negative pole of the dc bus 710 are both connected to the negative output terminal OUT-of the switch bridge arm unit 330.

It should be noted that the bus capacitor C1 may store the pre-charged electric energy, and may also stabilize the voltages of the positive output end OUT + and the negative output end OUT-of the switching arm unit 330 (i.e., the voltage on the dc bus 710). In the circuit diagram shown in fig. 2, the switching leg unit 330 includes N pairs of switching tubes, where N is equal to 2, each pair of switching tubes is connected in series, each pair of switching tubes connected in series is connected between two output ends of the switching leg unit 330, and each switching tube has a parasitic diode (which may also be referred to as a body diode), so that when the switching tubes in the switching leg unit 330 are all turned off, the parasitic diodes have one-way conduction, and the switching leg unit 330 is equivalent to a rectification circuit composed of N pairs of diodes. Therefore, the ac input from the ac source 800 is current-limited by the pre-charge circuit 400, and then converted between ac and dc by the equivalent rectification circuit of the switching arm unit 330, so as to output dc, which is output via the dc bus 710. At this time, because the post-stage circuit is not started or the overall power consumption is low, the electric energy output through the dc bus 710 can charge the bus capacitor C1 connected to the dc bus 710, so that the voltage on the bus capacitor C1 gradually rises to the pre-charging voltage. After the pre-charging is completed, the control circuit 500 controls the pre-charging circuit 400 to be turned off, and further controls the main switch unit 310 to be turned on, and at this time, the control circuit 500 outputs a corresponding driving signal according to the target output voltage and the input voltage of the ac source 800 to control the duty ratio and the switching frequency of the switching tube in the switching arm unit 330, so as to implement ac/dc conversion and output. Therefore, multiplexing of the switching tubes in the switching leg unit 330 can be realized by the above circuit. In the embodiment, the pre-charging operation of the bus capacitor C1 can be realized by multiplexing the switch tubes in the switch bridge arm unit 330, and other electronic devices are not required to be additionally added, so that the space requirement and the implementation cost of the circuit board are reduced.

It is easy to understand that, in a specific implementation, since the switching leg unit 330 includes N pairs of switching tubes, and N may be a positive integer greater than or equal to 2, the number of switching tubes in the switching leg unit 330 may be configured according to an actual requirement, that is, a specific value of N may be configured according to an actual requirement.

As shown in fig. 2, as an embodiment, the pre-charge switch unit 410 includes a first switch S1, and the main switch unit 310 includes a second switch S2.

In fig. 2, for example, the first switch S1 and the second switch S2 may be MOS transistors, relays, or the like, and suitable switching devices may be selected according to actual situations.

In another embodiment, the first switch S1 and the second switch S2 may also be knob switches or push switches for manual control of the power supply circuit 100.

As shown in fig. 2, in the present embodiment, the pre-charge resistor unit 420 includes a current limiting resistor R1. A first end of the current limiting resistor R1 is connected to the pre-charge switch unit 410, and a second end of the current limiting resistor R1 is connected to the second node P2.

When the pre-charge switch unit 410 is turned on, the pre-charge circuit 400 may short-circuit the main switch unit 310 and the boost unit 320, so that the switch leg unit 330 is communicated with the ac connection port 200. The current limiting resistor R1 is used for dividing and limiting the alternating current provided by the alternating current source 800, so that the switch bridge arm unit 330 and the pre-charged energy storage device connected to the direct current bus 710 can be protected, and the switch bridge arm unit 330 and the pre-charged energy storage device are prevented from being damaged by surge voltage.

As shown in fig. 2, for one embodiment, the boosting unit 320 includes an inductor L1. A first end of the inductor L1 is connected to the main switch unit 310, and a second end of the inductor L1 is connected to the switch leg unit 330 to form a second node P2. The boost unit 320 is configured to form a Power Factor Correction (PFC) boost circuit with the switch bridge arm unit 330 when the Power supply circuit 100 performs conventional Power supply, and boost and convert ac and dc input voltages provided by the ac source 800.

As shown in fig. 2, in this embodiment, the control circuit 500 is respectively connected to the switching tubes in the pre-charge switching unit 410, the main switching unit 310 and the switching leg unit 330, and the control circuit 500 can respectively control the switching tubes in the pre-charge switching unit 410, the main switching unit 310 and the switching leg unit 330 to be turned on or off.

Illustratively, the control circuit 500 may be a microcontroller or a single chip microcomputer, and the control circuit 500 may output corresponding control signals to control the on/off of each switching tube in the pre-charge switching unit 410, the main switching unit 310 and the switching arm unit 330.

As shown in fig. 2, as an embodiment, the switching leg unit 330 includes a first switching tube Q1, a second switching tube Q2, a third switching tube Q3, and a fourth switching tube Q4. A first conduction end of the first switching tube Q1 is connected to the positive electrode of the dc bus 710, and a second conduction end of the first switching tube Q1 is connected to the second node P2. The first conduction end of the second switch tube Q2 is connected to the second conduction end of the first switch tube Q1, and the second conduction end of the second switch tube Q2 is connected to the negative electrode of the dc bus 710. A first conduction terminal of the third switching tube Q3 is connected to the positive electrode of the dc bus 710, and a second conduction terminal of the third switching tube Q3 is connected to the first input terminal IN1 of the ac connection port 200. A first conduction end of the fourth switching tube Q4 is connected to a second conduction end of the third switching tube Q3, and a second conduction end of the fourth switching tube Q4 is connected to a negative electrode of the dc bus 710. The first switching tube Q1, the second switching tube Q2, the third switching tube Q3 and the fourth switching tube Q4 are all provided with parasitic diodes. The control ends of the first switch tube Q1, the second switch tube Q2, the third switch tube Q3 and the fourth switch tube Q4 are all connected with the control circuit 500.

The first conduction end of the first switch tube Q1 and the first conduction end of the third switch tube Q3 are positive output ends OUT + of the switch bridge arm units 330, and the second conduction end of the second switch tube Q2 and the second conduction end of the fourth switch tube Q4 are negative output ends OUT-of the switch bridge arm units 330. The first switch tube Q1, the second switch tube Q2, the third switch tube Q3 and the fourth switch tube Q4 can be MOS tubes or IGBT tubes. In this embodiment, the first switch Q1, the second switch Q2, the third switch Q3 and the fourth switch Q4 are NMOS transistors, a drain of each NMOS transistor corresponds to the first conducting end of each switch, a source of each NMOS transistor corresponds to the second conducting end of each switch, and a gate of each NMOS transistor corresponds to the control end of each switch. The anode of the parasitic diode of each switching tube is connected with the second conduction end of the corresponding switching tube, and the cathode of the parasitic diode of each switching tube is connected with the first conduction end of the corresponding switching tube.

In the case of pre-charging the power supply circuit 100, when the ac power supplied by the ac source 800 is in a positive half-cycle, the current flows from the second conducting terminal of the first switch tube Q1 and is transmitted to the first terminal of the bus capacitor C1 (the positive electrode of the dc bus 710) through the parasitic diode of the first switch tube Q1, and at this time, the pre-charging circuit 400, the parasitic diode of the first switch tube Q1, the bus capacitor C1, and the parasitic diode of the fourth switch tube Q4 form a pre-charging loop. When the alternating current provided by the alternating current source 800 is in a negative half cycle, current flows from the second conducting end of the third switching tube Q3 and is transmitted to the first end of the bus capacitor C1 (the positive electrode of the direct current bus 710) through the parasitic diode of the third switching tube Q3, and at this time, the precharge circuit 400, the parasitic diode of the third switching tube Q3, the bus capacitor C1, and the parasitic diode of the second switching tube Q2 form a precharge circuit. And further, rectification of alternating current and pre-charging of the bus capacitor C1 are achieved. By pre-charging the bus capacitor C1, the voltage on the dc bus 710 is first boosted, so that the impact on the bus capacitor C1 and other devices connected to the dc bus 710 due to excessive voltage drop during direct conventional power supply can be avoided.

Under the condition that the power supply circuit 100 performs conventional power supply, when the alternating current provided by the alternating current source 800 is in a positive half cycle, the control circuit 500 controls the first switching tube Q1 and the fourth switching tube Q4 to be switched on and off according to a preset duty ratio and a switching frequency, and controls the second switching tube Q2 and the third switching tube Q3 to be switched off in the whole positive half cycle; when the ac power provided by the ac source 800 is in a negative half-cycle, the control circuit 500 may control the first switching tube Q1 and the fourth switching tube Q4 to be turned off during the whole negative half-cycle, and control the second switching tube Q2 and the third switching tube Q3 to be turned on and off according to a preset duty ratio and a switching frequency. Corresponding control signals are output through the control circuit 500 to control the conduction or the disconnection of each switching tube in the switching arm unit 330, so that the rectification and the boosting of alternating current can be realized, and corresponding direct current signals are output.

As an example, assuming that the ac source 800 is a three-phase current source, and the switching leg unit 330 is used to rectify the three-phase ac current, at least 3 pairs of switching tubes may be configured in the switching leg unit 330, that is, N is equal to 3.

Fig. 3 shows a schematic structural diagram of the power supply circuit 100 according to another embodiment, and as shown in fig. 3, in another embodiment, the power supply circuit 100 further includes a filtering unit 340, a first end of the filtering unit 340 is connected between the main switching unit 310 and the voltage boosting unit 320, and a second end of the filtering unit 340 is connected to the ac connection port 200.

The filtering unit 340 is used for filtering the alternating current provided by the alternating current source 800 to filter the interference signal therein when the power is normally supplied through the AC/DC conversion circuit 300.

Specifically, fig. 4 shows a circuit schematic diagram of the power supply circuit 100 according to another embodiment, as shown IN fig. 4, the filtering unit 340 includes a capacitor C2, a first end of the capacitor C2 is connected to a first end of the inductor L1, and a second end of the capacitor C2 is connected to the first input terminal IN1 of the ac connection port 200. The capacitor C2 and the inductor L1 may form an LC filter circuit for filtering high frequency signals.

As shown in fig. 5, based on any of the above embodiments, in another embodiment, the power supply circuit 100 further includes a detection unit 600, the detection unit 600 is respectively connected to the dc bus 710 and the control circuit 500, the detection unit 600 is configured to detect a voltage on the dc bus 710 and transmit a corresponding detected voltage to the control circuit 500, and the control circuit 500 is further configured to, when the power supply circuit 100 accesses the ac source 800, control the pre-charge switch unit 410 to be turned on for pre-charging, and when the detected voltage reaches a preset voltage, control the pre-charge switch unit 410 to be turned off, and control the main switch unit 310 to be turned on and control the respective switch tubes of the switch bridge arm unit 330 to be correspondingly turned on or off for performing normal power supply.

In this embodiment, when the control circuit 500 receives the detection voltage, the detection voltage may be compared with the preset voltage, and if the detection voltage reaches the preset voltage, the control circuit 500 controls the power supply circuit 100 to change from the pre-charge to the normal power supply, so that the automatic switching of the power supply mode may be realized.

As shown in fig. 5, the power supply circuit 100 further includes a DC/DC converter circuit 720, and the DC/DC converter circuit 720 is connected to the DC bus 710 and the control circuit 500, respectively. The DC/DC conversion circuit 720 may be connected to other devices, devices or circuits, and is configured to convert the DC power on the DC bus 710 into DC power with a preset voltage and output the DC power. The DC/DC conversion circuit 720 may specifically include a DC transformer chip or a chopper circuit.

The control circuit 500 is further configured to control the DC/DC conversion circuit 720 to stop operating when the pre-charge switch unit 410 is controlled to be turned on, so as to avoid power loss on the pre-charged energy storage device connected to the DC bus 710 during pre-charging.

An embodiment of the present application further provides an electronic device, including the power supply circuit according to any of the above embodiments.

Fig. 6 shows a schematic structural diagram of an electronic device 900 provided in an embodiment of the present application, and as shown in fig. 6, the electronic device 900 further includes an energy storage unit 910.

In this embodiment, the energy storage unit 910 is connected to the power supply circuit 100 to obtain the electrical signal provided by the power supply circuit 100.

The electronic device 900 provided in this embodiment may be an energy storage device, and accordingly, the energy storage unit 910 may be a rechargeable battery, and the specific type of the electronic device 900 is not limited in this embodiment.

Fig. 7 shows a schematic structural diagram of an electronic device 900 according to another embodiment of the present application, and as shown in fig. 7, the electronic device 900 further includes an electricity utilization unit 920.

In this embodiment, the power utilization unit 920 is connected to the power supply circuit 100 to obtain the electrical signal provided by the power supply circuit 100.

The electronic device 900 provided by the present embodiment may be a power consumption device, and accordingly, the power consumption unit 920 may be a dc motor or a dc lighting device.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned function distribution may be performed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules to perform all or part of the above-mentioned functions. Each functional unit and module in the embodiments may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present application. The specific working processes of the units and modules in the system may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the above embodiments, the description of each embodiment has its own emphasis, and reference may be made to the related description of other embodiments for parts that are not described or recited in any embodiment.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims (10)

1. A power supply circuit, comprising:

an AC connection port;

the AC/DC conversion circuit is configured with a main switch unit, a boosting unit and a switch bridge arm unit, the main switch unit is connected with the alternating current connection port to form a first node, and the main switch unit is connected with the boosting unit in series; the boosting unit is connected with the switch bridge arm unit to form a second node, and the output end of the switch bridge arm unit is used for being connected with a direct current bus; the switching bridge arm unit comprises N pairs of switching tubes, each switching tube is provided with a parasitic diode, and N is a positive integer greater than or equal to 2;

a precharge circuit connected between the first node and the second node, the precharge circuit being configured with a precharge switch unit and a precharge resistance unit;

and the control circuit is connected with the main switch unit, the switch bridge arm unit and the pre-charging switch unit, and is configured to switch on the pre-charging switch unit, switch off the main switch unit and switch off a switch tube in the switch bridge arm unit when the alternating current connection port is connected with an alternating current source, so that the alternating current source outputs a pre-charging signal after passing through the pre-charging circuit and a parasitic diode of the switch bridge arm unit.

2. The power supply circuit of claim 1, wherein the pre-charge resistance unit includes a current limiting resistance;

and the first end of the current-limiting resistor is connected with the pre-charging switch unit, and the second end of the current-limiting resistor is connected with the second node.

3. The power supply circuit of claim 1 wherein the boost unit comprises an inductor;

and the first end of the inductor is connected with the main switch unit, and the second end of the inductor is connected with the switch bridge arm unit to form the second node.

4. The power supply circuit according to claim 3, further comprising a filter unit, a first end of the filter unit being connected between the main switching unit and the boosting unit; and the second end of the filtering unit is connected with the alternating current connection port.

5. The power supply circuit of claim 4 wherein said filter unit comprises a capacitor, a first terminal of said capacitor being connected to a first terminal of said inductor, a second terminal of said capacitor being connected to said AC connection port.

6. The power supply circuit according to any one of claims 1 to 4, further comprising a DC/DC conversion circuit connected to the DC bus and the control circuit, respectively; the DC/DC conversion circuit is used for converting the direct current on the direct current bus into direct current with preset voltage and outputting the direct current;

the control circuit is further used for controlling the DC/DC conversion circuit to stop working when the pre-charging switch unit is controlled to be conducted.

7. The power supply circuit according to any one of claims 1 to 4, further comprising a bus capacitor connected between the positive and negative poles of the DC bus.

8. The power supply circuit according to any one of claims 1 to 4, further comprising a detection unit configured to detect a voltage on the DC bus and transmit a corresponding detected voltage to the control circuit, wherein the control circuit is further configured to control the pre-charge switch unit to be turned on when the AC connection port is connected to the AC source, and to control the pre-charge switch unit to be turned off and the main switch unit to be turned on when the detected voltage reaches a preset voltage.

9. The power supply circuit according to claim 7, wherein the switching leg unit comprises a first switching tube, a second switching tube, a third switching tube and a fourth switching tube;

a first conduction end of the first switch tube is connected with the positive electrode of the direct current bus, and a second conduction end of the first switch tube is connected with the second node;

the first conduction end of the second switch tube is connected with the second conduction end of the first switch tube, and the second conduction end of the second switch tube is connected with the negative electrode of the direct current bus;

the first conducting end of the third switching tube is connected with the positive electrode of the direct current bus, and the second conducting end of the third switching tube is connected with the negative electrode of the alternating current connecting port;

and a first conduction end of the fourth switching tube is connected with a second conduction end of the third switching tube, and a second conduction end of the fourth switching tube is connected with the negative electrode of the direct-current bus.

10. An electronic device, characterized in that it comprises a supply circuit according to any one of claims 1-9.

Images