CN116345939A - Power supply circuit and its load identification method and electronic equipment - Google Patents

Abstract

The application provides a power supply circuit, a load identification method thereof and electronic equipment, wherein the load identification method comprises the following steps: acquiring the input power of a direct-current end of the inverter circuit; comparing the input power with a preset power threshold, and confirming that the alternating-current end of the inverter circuit is connected with the load when the input power is larger than the preset power threshold; the preset power threshold is the no-load power of the direct-current end of the inverter circuit when the inverter circuit is in an no-load state. According to the method, the input power of the direct-current end of the inverter circuit is compared with the preset power threshold value, so that even if the external load is a low-power load, the input power of the direct-current end of the inverter circuit can be influenced, and whether the alternating-current end of the inverter circuit is connected with the load or not can be accurately identified under the condition of the low-power load, and therefore the identification accuracy of the load condition of the inverter circuit can be effectively improved.

Description

Power supply circuit and its load identification method and electronic equipment

technical field

The present application relates to the technical field of inverter circuits, in particular to a power supply circuit and its load identification method and electronic equipment.

Background technique

In the inverter circuit, after the DC voltage passes through the inverter circuit, the output terminal of the inverter circuit outputs an AC voltage. Currently, when the output end of the inverter circuit is loaded, the output power is calculated by sampling the output current at the output end and multiplying it by the current output voltage. The disadvantage of this calculation method is that when the output terminal of the inverter circuit is connected to a low-power load, that is, when the output terminal of the inverter circuit is lightly loaded, the output power is small, and it is difficult to identify the connection of the output terminal of the inverter circuit. There is a load, for example, the output voltage of the inverter circuit is 220V, and the connected load power is 5W, then the working current at the output terminal is about 23mA, and it is difficult for the current sampling circuit to detect this current, so the current identification of the load condition of the inverter circuit The accuracy is low, so it is easy to judge it as no-load and control the inverter circuit to stop working.

Contents of the invention

In view of this, the present application provides a power supply circuit and its load identification method and electronic equipment, aiming at solving the problem that the identification accuracy of the inverter circuit for the load condition is not high.

The first aspect of the present application provides a load identification method for a power supply circuit. The power supply circuit includes an inverter circuit, the DC terminal of the inverter circuit is used to connect a DC power supply, and the AC terminal of the inverter circuit is used to connect a load. The load identification method includes: Obtain the input power of the DC end of the inverter circuit; compare the input power with the preset power threshold, and confirm that the AC end of the inverter circuit is connected to a load when the input power is greater than the preset power threshold; wherein, the preset power threshold is The no-load power of the DC terminal of the inverter circuit when the inverter circuit is in the no-load state.

In the load identification method of the present application, since the change of the load connected to the AC terminal of the inverter circuit will affect the power of its DC terminal, when the load becomes smaller, the input power of the DC terminal of the inverter circuit will also decrease accordingly, so that by obtaining the inverter The input power of the DC end of the circuit is compared with the preset power threshold, that is, compared with the no-load power. When the input power is greater than the preset power threshold, it can be confirmed that the AC end of the inverter circuit is connected to a load. Moreover, even if the external load is a low-power load, it will also affect the input power of the DC terminal of the inverter circuit, so that in the case of a low-power load, the inverter can be accurately identified by obtaining the input power of the DC terminal of the inverter circuit. Whether the AC terminal of the circuit is connected with a load, therefore, the load identification method of the present application can effectively improve the identification accuracy of the load status of the inverter circuit.

In one embodiment, before obtaining the input power of the DC terminal of the inverter circuit, the load identification method further includes: obtaining the input current and input voltage of the DC terminal of the inverter circuit when the inverter circuit is in a no-load state, and according to the input Current and input voltage calculate preset power thresholds.

In one of the embodiments, when it is confirmed that the AC end of the inverter circuit is connected to a load, the load identification method further includes: obtaining the output current and output voltage of the AC end of the inverter circuit; calculating the output current and output voltage of the inverter circuit according to the output current and output voltage The output power of the AC terminal, and an inverter control command is generated according to the output power. The inverter control command contains inverter control information, and the inverter control command is used to instruct the inverter circuit to perform power adjustment according to the inverter control information.

In one embodiment, the load identification method further includes: when the input power is less than or equal to the preset power threshold, confirming that the inverter circuit is in a no-load state, and generating an inverter stop instruction, the inverter stop instruction is used to instruct the inverter circuit stop working.

The second aspect of the present application provides a power supply circuit, including an inverter circuit and a main control circuit; the DC terminal of the inverter circuit is used to connect a DC power supply, the AC terminal of the inverter circuit is used to connect a load, the main control circuit and the inverter circuit connection, the main control circuit is used to: obtain the input power of the DC terminal of the inverter circuit; compare the input power with the preset power threshold, and confirm that there is a load connected to the AC terminal of the inverter circuit when the input power is greater than the preset power threshold ; Wherein, the preset power threshold is the no-load power of the DC terminal of the inverter circuit when the inverter circuit is in a no-load state.

In one of the embodiments, the inverter circuit includes a DC/DC conversion unit and an AC/DC conversion unit, and the input end of the DC/DC conversion unit is connected to the DC power supply for performing DC-DC conversion on the DC power output by the DC power supply Output; the input end of the AC/DC conversion unit is connected to the output end of the DC/DC conversion unit, the output end of the AC/DC conversion unit is used to connect the load, and the AC/DC conversion unit is used for the DC output of the DC/DC conversion unit Output after AC-DC conversion.

In one embodiment, the main control circuit includes a first sampling unit, the first sampling unit is arranged at the DC terminal of the inverter circuit, and the first sampling unit is used to perform current sampling and voltage sampling on the DC terminal of the inverter circuit, and Get the input power according to the sampling result.

In one embodiment, the first sampling unit includes: a first sampling resistor and a first voltage sampler; the first sampling resistor is connected to the DC terminal of the inverter circuit, and the first voltage sampler is connected to the first sampling resistor.

In one of the embodiments, the main control circuit further includes a second sampling unit and a control unit, the second sampling unit is used to perform voltage sampling and current sampling on the AC terminal of the inverter circuit, and generate output power according to the sampling results; the control unit Connected with the second sampling unit, the control unit is used to receive the output power, and when it is confirmed that the AC terminal of the inverter circuit is connected with a load, generate an inverter control instruction according to the output power, the inverter control instruction contains inverter control information, and the inverter The control instruction is used to instruct the inverter circuit to adjust power according to the inverter control information.

The third aspect of the present application provides an electronic device, including a power supply circuit, a memory, and a processor. The memory stores executable instructions of the processor, and the processor is used to execute the executable instructions to perform the steps of the load identification method as described above.

The fourth aspect of the present application provides a power supply device. The power supply device includes a DC power supply, a DC interface, a load interface, and the power supply circuit as before. The DC terminal of the inverter circuit in the power supply circuit is connected to the DC power supply through the DC interface. The inverter circuit The AC terminal is connected to the load through the load interface.

Description of drawings

FIG. 1 is a schematic structural diagram of a power supply circuit provided in a first embodiment of the present application.

Fig. 2 is a schematic structural diagram of a power supply circuit provided in a second embodiment of the present application.

Fig. 3 is a schematic circuit diagram of a power supply circuit provided by an embodiment of the present application.

Fig. 4 is a schematic flowchart of a load identification method provided by an embodiment of the present application.

Fig. 5 is a schematic structural diagram of an electronic device provided by an embodiment of the present application.

Description of main component symbols

power supply circuit 100

inverter circuit 10

DC/DC conversion unit 11

AC/DC conversion unit 12

Main control circuit 20

First sampling unit 21

The first sampling resistor R1

First voltage sampler 210

Second sampling unit 22

The second sampling resistor R2

Current transformer CT1

Second voltage sampler 220

control unit 23

DC power supply 200

Load 300

Electronic equipment 500

memory 510

Processor 520

Detailed ways

It should be noted that the terms "first" and "second" in the specification, claims and drawings of the present application are used to distinguish similar objects, rather than to describe a specific sequence or sequence.

In addition, it should be noted that the method disclosed in the embodiment of the application or the method shown in the flow chart includes one or more steps for realizing the method. Without departing from the scope of the claims, the multiple steps The order of execution can be interchanged with each other, and some of the steps can also be deleted.

Some embodiments will be described below with reference to the accompanying drawings. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

The inverter circuit is used to convert direct current into alternating current. When the output end of the inverter circuit is connected to a load, the converted alternating current supplies power to the load. In order to make the inverter circuit work normally, it is necessary to identify whether the output terminal of the inverter circuit is connected with a load. At present, the output power of the inverter circuit is calculated by detecting the output current and the output voltage of the output terminal of the inverter circuit, and it is judged according to the output power whether the output terminal of the inverter circuit is connected with a load. When the output terminal of the inverter circuit is connected to a low-power load, that is, when the output terminal of the inverter circuit is lightly loaded, the output current of the inverter circuit will be very small, and it is difficult to detect the output current and obtain the output power. It is impossible to recognize that the output terminal of the inverter circuit is connected to a load when it is loaded, and it is easy to think that the inverter circuit is no-load when the load is light, and control the inverter circuit to stop supplying power to the load.

For this reason, the embodiment of the present application provides a power supply circuit and its load identification method, which can improve the identification accuracy of the load status of the inverter circuit, and can also identify the load of the inverter circuit when the inverter circuit is lightly loaded. .

Please refer to FIG. 1 . FIG. 1 is a block diagram of a power supply circuit 100 provided by an embodiment of the present application.

As shown in FIG. 1 , the power supply circuit 100 includes an inverter circuit 10 and a main control circuit 20 , the DC terminal of the inverter circuit 10 is used for connecting a DC power source 200 , and the AC terminal of the inverter circuit 10 is used for connecting a load 300 .

The main control circuit 20 is connected with the inverter circuit 10, therefore, the main control circuit 20 can be used to obtain the input power of the DC terminal of the inverter circuit 10, and then compare the input power with the preset power threshold, and when the input power is greater than the preset power When the threshold value is reached, it is confirmed that the AC terminal of the inverter circuit 10 is connected to the load 300 . Wherein, the preset power threshold is the no-load power of the DC terminal of the inverter circuit 10 when the inverter circuit 10 is in a no-load state.

It can be understood that the power change of the load 300 connected to the AC terminal of the inverter circuit 10 will affect the input power of the DC terminal. When the power of the load 300 becomes smaller, the input power of the DC terminal of the inverter circuit 10 also decreases accordingly, so that by obtaining the input power of the DC terminal of the inverter circuit 10, the main control circuit 20 compares the obtained input power with the preset power threshold The comparison is to compare the input power of the DC terminal of the inverter circuit 10 with the no-load power. When the input power is less than or equal to the preset power threshold, it can be confirmed that the AC terminal of the inverter circuit 10 is no-load. When the input power is greater than the preset power threshold, it can be confirmed that the AC terminal of the inverter circuit 10 is connected to the load 300 , that is, the inverter circuit 10 is working under load. Moreover, even if the external load 300 is a low-power load 300 , the input power of the DC terminal of the inverter circuit 10 will be greater than the preset power threshold, so it can still be identified whether the AC terminal of the inverter circuit 10 is connected to the load 300 . Therefore, the power supply circuit 100 of the embodiment of the present application can effectively improve the identification accuracy of the load condition of the inverter circuit 10 by detecting the input power of the DC terminal of the inverter circuit 10, and prevent the AC terminal of the inverter circuit 10 from connecting low power When the load 300 is unrecognizable, it is considered that the inverter circuit 10 is unloaded, so that the inverter circuit 10 can supply power to the connected low-power load 300 when it is lightly loaded.

In some embodiments, as shown in FIG. 2 , the inverter circuit 10 includes a DC/DC conversion unit 11 and an AC/DC conversion unit 12 . The input end of the DC/DC conversion unit 11 is connected to the DC power supply 200 , and the DC/DC conversion unit 11 is used for performing DC-DC conversion on the DC power output by the DC power supply 200 and then outputting it. The input end of the AC/DC conversion unit 12 is connected to the output end of the DC/DC conversion unit 11, the output end of the AC/DC conversion unit 12 is used to connect the load 300, and the AC/DC conversion unit 12 is used for the DC/DC conversion unit 11 The output direct current is output after undergoing AC-DC conversion. In this embodiment, the DC/DC conversion unit 11 may be a circuit unit capable of DC voltage conversion, such as a Buck step-down unit, a Boost step-up unit, or an LLC resonance unit.

Please continue to refer to FIG. 2 , in some embodiments, the main control circuit 20 includes a first sampling unit 21 . The first sampling unit 21 is arranged at the DC end of the inverter circuit 10, and the first sampling unit 21 is used for sampling the current and voltage of the DC end of the inverter circuit 10, and obtaining input power according to the sampling result.

It can be understood that the embodiment of the present application does not limit the specific implementation structure of the first sampling unit 21 performing current sampling and voltage sampling on the DC terminal of the inverter circuit 10 . Exemplarily, the first sampling unit 21 may include an ammeter, a voltmeter and an arithmetic unit. The input current of the DC terminal of the inverter circuit 10 is collected by the ammeter, and the input voltage of the DC terminal of the inverter circuit 10 is collected by the voltmeter. The input power is calculated from the sampled values of the ammeter and voltmeter. Wherein, the arithmetic unit may be integrated in a control chip, a control unit, or a device, or may be an independently configured chip, device, etc. capable of performing calculations.

In one embodiment, the sampling resistor can also be connected in series at the DC end of the inverter circuit 10, and the voltage at both ends of the sampling resistor can be collected by a voltmeter, and the inverse can be obtained by the operator according to the voltage collected by the voltmeter and the resistance value of the sampling resistor. The input current of the DC terminal of the variable circuit 10 is combined with the input current and the sampled input voltage to obtain the input power.

In this embodiment, the input power of the inverter circuit 10 is calculated according to the input current and input voltage of the DC terminal of the inverter circuit 10 . When the inverter circuit 10 converts the DC power at the DC terminal into AC power, the input current at the DC terminal will be greater than the output current at the AC terminal. For example, when the AC terminal of the inverter circuit 10 is connected to a load 300 with a power of 5W and the input voltage at the DC terminal is 24V, if the efficiency and loss of the inverter are not considered, the input current is 210mA, while the output current is 23mA, relatively In other words, an input current of 210mA is easier to detect and identify than an output current of 23mA. That is to say, when the AC end is connected to the low-power load 300 , the input current of the inverter circuit 10 will be greater than the output current, and it is easier to detect and identify the input current than the output current. Therefore, it is easier to calculate the input power according to the sampled input current and input voltage, and judge whether the inverter is loaded according to whether the input power is greater than the no-load power of the inverter. Apparently, based on such a design, the accuracy of identifying the load condition of the inverter can be improved.

As shown in FIG. 2 , in some embodiments, the main control circuit 20 may further include a second sampling unit 22 and a control unit 23 . The second sampling unit 22 is used for performing voltage sampling and current sampling on the AC terminal of the inverter circuit 10, and generating output power according to the sampling results. The control unit 23 is connected to the second sampling unit 22, and the control unit 23 is used to receive the output power, and when it is confirmed that the AC end of the inverter circuit 10 is connected to the load 300, generate an inverter control instruction according to the output power. The inverter control instruction includes inverter control information, and the inverter control instruction is used to instruct the inverter circuit 10 to perform power adjustment according to the inverter control information.

Specifically, when the inverter circuit 10 converts direct current into alternating current for output, due to factors such as the switching speed of the switching tube in the inverter circuit 10, the saturation voltage drop, and load disturbance, the alternating current output by the alternating current terminal of the inverter circuit 10 will not be stable. Stability affects the efficiency of the inverter circuit 10 . Therefore, in the embodiment of the present application, the control unit 23 will adjust the output power of the inverter circuit 10 according to the output power obtained by the second sampling unit 22, so that the error of the output power of the AC terminal of the inverter circuit 10 can be reduced, thereby The stability of the alternating current output by the inverter circuit 10 is improved. Wherein, the control unit 23 can output a control signal to each switch tube of the inverter circuit 10 according to the obtained output power, thereby controlling the switching frequency of the switch tube, adjusting the output voltage and/or output current of the AC terminal of the inverter, thereby adjusting the output power.

The working principle of the power supply circuit 100 provided by the present application will be described below in conjunction with FIG. 2 and FIG. 3 , and by taking the circuit diagram of the power supply circuit 100 shown in FIG. 3 as an example:

The DC/DC conversion unit 11 includes a first switching tube Q1, a second switching tube Q2, a third switching tube Q3, a fourth switching tube Q4, a fifth switching tube Q5, a sixth switching tube Q6, a transformer T1, a resonant inductor L1, The DC terminal capacitor C1, the first resonant capacitor C2 and the second resonant capacitor C3. Optionally, the first switching tube Q1, the second switching tube Q2, the third switching tube Q3, and the fourth switching tube Q4 may be MOS tubes, and the fifth switching tube Q5 and the sixth switching tube Q6 may be triodes.

The source of the first switching transistor Q1 is connected to the drain of the second switching transistor Q2 to form a first bridge arm, the source of the third switching transistor Q3 is connected to the drain of the fourth switching transistor Q4 to form a second bridge arm, and the fifth The emitter of the switching tube Q5 is connected to the collector of the sixth switching tube Q6 to form a third bridge arm. The drains of the first switch Q1 and the third switch Q3 are both connected to the positive DC terminal BAT+, and the sources of the second switch Q2 and the fourth switch Q4 are connected to the negative DC terminal BAT-. The first bridge arm and the second bridge arm are connected in parallel with the DC terminal capacitor C1 , and the DC terminal capacitor C1 can be connected in parallel at both ends of the DC power supply 200 .

One end of the primary coil of the transformer T1 is connected to a connection node between the source of the first switching transistor Q1 and the drain of the second switching transistor Q2 . The other end of the primary coil of the transformer T1 is connected to the connection node between the source of the third switching transistor Q3 and the drain of the fourth switching transistor Q4 . One end of the secondary coil of the transformer T1 is connected to the connection node between one end of the resonant inductor L1 and one end of the first resonant capacitor C2, the other end of the first resonant capacitor C2 is connected to the collector of the fifth switching tube Q5, and the other end of the resonant inductor L1 One end is connected to one end of the second resonant capacitor C3, and the other end of the second resonant capacitor C3 is connected to the emitter of the sixth switching transistor Q6. The other end of the secondary coil of the transformer T1 is connected to the connection node between the emitter of the fifth switching tube Q5 and the collector of the sixth switching tube Q6, and the collector of the fifth switching tube Q5 and the emitter of the sixth switching tube Q6 The output end of the DC/DC conversion unit 11 is formed between the poles. Wherein, the output end of the DC/DC conversion unit 11 may be connected to the input end of the AC/DC conversion unit 12 through a DC bus.

It can be understood that the gate of the first switch Q1, the gate of the second switch Q2, the gate of the third switch Q3 and the gate of the fourth switch Q4 are respectively used to receive signals for controlling their on-off . The bases of the fifth switching transistor Q5 and the sixth switching transistor Q6 are also respectively used to receive signals for controlling their on-off.

The DC/DC conversion unit 11 receives the input voltage of the DC power supply 200 through the DC terminal capacitor C1, and performs DC conversion on the input voltage through the first bridge arm, the second bridge arm, the transformer T1 and the third bridge arm, and converts the input voltage into a target voltage, and The target voltage is output to the AC/DC conversion unit 12 . Wherein, the target voltage can be higher or lower than the input voltage.

Of course, the DC/DC conversion unit 11 in the embodiment of the present application is not limited thereto, for example, it can also be configured as a Buck voltage reducing circuit, a Boost voltage boosting circuit, and the like.

In one embodiment, the AC/DC converting unit 12 includes a seventh switching transistor Q7 , an eighth switching transistor Q8 , a ninth switching transistor Q9 , a tenth switching transistor Q10 and an output inductor L2 . Optionally, the seventh switch tube Q7, the eighth switch tube Q8, the ninth switch tube Q9, and the tenth switch tube Q10 may be triodes.

Specifically, the emitter of the seventh switching tube Q7 is connected to the collector of the eighth switching tube Q8 to form a fourth bridge arm, and the emitter of the ninth switching tube Q9 is connected to the collector of the tenth switching tube Q10 to form a fifth bridge arm. , the fourth bridge arm and the fifth bridge arm are connected in parallel to the output end of the DC/DC conversion unit 11 (that is, in parallel with the third bridge arm). The collectors of the seventh switching transistor Q7 and the ninth switching transistor Q9 are connected to the positive pole BUS+ of the DC bus, and the emitters of the eighth switching transistor Q8 and the emitters of the tenth switching transistor Q10 are connected to the negative pole BUS- of the DC bus. It can be understood that the bases of the seventh switching transistor Q7 , the eighth switching transistor Q8 , the ninth switching transistor Q9 and the tenth switching transistor Q10 are respectively used to receive signals for controlling their on-off.

One end of the output inductor L2 is connected to the connection node between the emitter of the ninth switching tube Q9 and the collector of the tenth switching tube Q10, the other end of the output inductor L2 is connected to the live wire port IN_OUT_L of the AC output end, and the seventh switching tube Q7 The emitter of the eighth switching tube Q8 and the collector of the eighth switch tube Q8 are connected to the neutral line port IN_OUT_N of the AC output end. The AC/DC conversion unit 12 is connected to the load 300 through the live wire port IN_OUT_L and the neutral wire port IN_OUT_N.

In the AC/DC conversion unit 12, the seventh switch tube Q7 and the tenth switch tube Q10 are turned on and off at the same time, the eighth switch tube Q8 and the ninth switch tube Q9 are turned on and off at the same time, and the seventh switch tube Q7 The eighth switching tube Q8 is turned on and off alternately, so as to convert the target voltage output by the DC/DC conversion unit 11 into an AC output, so as to provide power to the load 300 .

The power supply circuit 100 also includes a bus capacitor C4, which is connected in parallel between the output end of the DC/DC conversion unit 11 and the input end of the AC/DC conversion unit 12, and one end of the bus capacitor C4 is connected to the collector of the seventh switching tube Q7 It is connected to the positive pole BUS+ of the DC bus, and the other end of the bus capacitor C4 is connected to the emitter of the eighth switching transistor Q8 and the BUS- of the DC bus. That is, the bus capacitor C4 is connected in parallel between the third bridge arm and the fourth bridge arm.

The target voltage output by the DC/DC conversion unit 11 is output to the bus capacitor C4 for storage, and the target voltage stored in the bus capacitor C4 is converted into alternating current by the AC/DC conversion unit 12 .

The first sampling unit 21 includes a first sampling resistor R1 and a first voltage sampler 210, the first terminal of the first sampling resistor R1 is connected to the source of the second switching transistor Q2, the second terminal of the first sampling resistor R1 is connected to the inverter The negative pole of the DC terminal of the inverter circuit 10 is connected to BAT−, and the negative pole of the DC terminal BAT− and the positive pole of the DC terminal of the inverter circuit 10 are used to connect to the DC power supply 200 . The first voltage sampler 210 is connected to the first sampling resistor R1. The input current of the DC terminal of the inverter circuit 10 flows through the first sampling resistor R1, and the voltage across the first sampling resistor R1 is collected by the first voltage sampler 210, and the collected voltage and the resistance value of the first sampling resistor R1 can be calculated as out the input current.

Certainly, in the embodiment of the present application, the first sampling unit 21 may also be an ammeter and a voltmeter. For example, an ammeter is connected in series at the DC end of the inverter circuit 10 to directly sample the input current of the inverter circuit 10, and a voltmeter is connected between the positive pole and the negative pole of the DC end of the inverter circuit 10, and the voltmeter directly samples the input current of the inverter circuit 10. 10 input voltage. It can be understood that, in order to obtain the input power of the inverter circuit 10 according to the sampling result, the first sampling unit 21 may also include a unit, module or device with computing functions, such as a control chip.

The second sampling unit 22 may include a current transformer CT1 , a second sampling resistor R2 and a second voltage sampler 220 . The primary winding of the current transformer CT1 is connected in series with the live wire port IN_OUT_L of the AC output end of the inverter, and the secondary winding of the current transformer CT1 is connected in parallel with the second sampling resistor R2. The second voltage sampler 220 is used to collect the voltage across the second sampling resistor R2, and the output current of the AC terminal of the inverter circuit 10 can be obtained according to the voltage collected by the second voltage sampler 220 and the resistance value of the second sampling resistor R2 . The second sampling unit 22 can also include a third voltage sampler for collecting the output voltage of the AC terminal of the inverter circuit 10, and the output of the inverter circuit 10 can be obtained according to the output current and the output voltage collected by the third voltage sampler. power. The second sampling unit 22 sends the output power of the inverter circuit 10 to the control unit 23, so that the control unit 23 generates an inverter control command according to the output power, so that the inverter circuit 10 performs power conversion according to the inverter control information included in the inverter control command. Adjustment. For example, the inverter control information contained in the inverter control instruction may be the duty cycle of the control signal for controlling each switch tube in the inverter circuit 10, and the inverter circuit 10 adjusts the duty cycle of the control signal for each switch tube according to the inverter control signal. Duty ratio, thereby adjusting the output power of the inverter circuit 10.

It can be understood that the specific structure of the second sampling unit 22 is not limited to this embodiment, for example, the second sampling unit 22 can also set the voltage and current of the AC terminal of the inverter circuit 10 by a Hall sensor, an ammeter, a voltmeter, etc. Take a sample.

FIG. 4 is a flow chart of a method for identifying a load of a power supply circuit 100 provided in an embodiment of the present application. In at least one implementation manner, the load identification method is applied to the power supply circuit 100 as before, and the load identification method includes:

S 10. Obtain the input power of the DC terminal of the inverter circuit.

Wherein, the input power may be obtained by sampling the input current and input voltage of the DC terminal of the inverter circuit 10, and then calculating the input power according to the sampled input current and input voltage.

S20. Comparing the input power with a preset power threshold, and confirming that the AC end of the inverter circuit is connected to the load 300 when the input power is greater than the preset power threshold.

Wherein, the preset power threshold is the no-load power of the DC terminal of the inverter circuit 10 when the inverter circuit 10 is in a no-load state. The captured input power is compared to a preset power threshold. When the comparison shows that the input power is less than or equal to the preset power threshold, it can be confirmed that the AC terminal of the inverter circuit 10 is unloaded. When the comparison shows that the input power is greater than the preset power threshold, it means that the AC terminal of the inverter circuit 10 is connected to the load 300 , that is, the inverter circuit 10 is working under load.

In the load identification method provided by the embodiment of the present application, since the change of the load 300 connected to the AC end of the inverter circuit 10 will affect the power of its DC end, by comparing the acquired input power with the preset power threshold, that is, the inverter The input power of the DC end of the inverter circuit 10 is compared with the no-load power, and when the input power is greater than a preset power threshold, it can be confirmed that the AC end of the inverter circuit 10 is connected to the load 300 . Even if the external load 300 is a low-power load, it will affect the input power of the DC terminal of the inverter circuit 10 , so that it can still accurately identify whether the AC terminal of the inverter circuit 10 is connected to the load 300 in the case of a low-power load. Therefore, the load identification method of the embodiment of the present application can effectively improve the identification accuracy of the load condition of the inverter circuit 10 .

It can be understood that, before step S10, the load identification method may also include:

When the inverter circuit 10 is in the no-load state, the input current and input voltage of the DC terminal of the inverter circuit 10 are obtained, and the preset power threshold is calculated according to the input current and the input voltage.

That is to say, when the AC terminal of the inverter circuit 10 is unloaded, the inverter circuit 10 is controlled to start converting the input voltage of the DC terminal into AC power, and current sampling and voltage sampling are performed on the DC terminal of the inverter circuit 10 to obtain the inverter The input current and input voltage when the circuit 10 is no-load, so as to calculate the no-load power of the DC terminal of the inverter circuit 10, that is, the preset power threshold.

In the embodiment of the present application, considering that the input voltage provided by the DC power supply 200 connected to the DC end of the inverter circuit 10 and the operating frequency of each switching tube in the inverter circuit 10 may be different when the inverter circuit 10 starts to work each time, there will be As a result, there is a difference in the corresponding no-load power when the inverter circuit 10 starts to work each time. Therefore, in order to further improve the accuracy of load identification, in the embodiment of the present application, when starting the inverter circuit 10, the inverter circuit 10 can be unloaded first, and the input current and input voltage at this time can be sampled to obtain the no-load power. The load power is stored as a preset power threshold, so as to realize the calibration of the preset power threshold, so that the preset power threshold used for load identification conforms to the current working parameters of the inverter circuit 10 .

Of course, it can be understood that if the inverter circuit 10 is fixedly installed in a power supply device, the input voltage provided by the DC power supply 200 in the power supply device to the inverter circuit 10 at any time is a certain value or a certain range. Before the power supply device leaves the factory, the inverter circuit 10 is started at no-load to obtain its no-load power, and the obtained no-load power is saved as a preset power threshold and stored in the controller or control chip of the inverter circuit 10 . When performing load identification, the stored preset power threshold is directly used for comparison with the acquired input power of the DC terminal of the inverter circuit 10 .

In some embodiments, the load identification method may also include:

When the input power is less than or equal to the preset power threshold, it is confirmed that the inverter circuit 10 is in a no-load state, and an inverter stop instruction is generated, and the inverter stop instruction is used to instruct the inverter circuit 10 to stop working.

When it is confirmed that the inverter circuit 10 is in the no-load state, an inverter stop command may be generated to control the inverter circuit 10 to stop working. In this way, it can prevent the inverter circuit 10 from continuing to work when it is no-load, which will consume the electric energy of the DC power supply 200 , cause waste of electric energy, or damage the components of the inverter circuit 10 .

Referring to FIG. 5 , FIG. 5 shows a schematic diagram of an electronic device 500 provided in an embodiment of the present application.

In one embodiment of the present application, the electronic device 500 includes, but is not limited to, a power supply circuit 100, a memory 510, a processor 520, and executable instructions stored in the memory 510, and the processor 520 is used to execute Instructions are executable to perform the steps of the aforementioned load identification method.

Processor 520 may be a central processing unit (Central Processing Unit, CPU), and may also be other general-purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), on-site Programmable gate array (Field Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The processor 520 is the computing core and control center of the power supply circuit 100, and uses various interfaces and lines to connect various parts of the entire power supply circuit 100 , and acquire parameters such as input power and output power of the inverter circuit 10 in the power supply circuit 100 .

The processor 520 acquires parameters such as input power and output power of the inverter circuit 10 in the power supply circuit 100 . The processor 520 acquires the foregoing parameters to implement the steps in the foregoing embodiment of the load identification method, as shown in FIG. 4 .

The memory 510 can be used to store executable instructions, and the processor 520 implements various functions of the power supply circuit 100 by executing or obtaining the executable instructions stored in the memory 510 and calling the data stored in the memory 510 . The memory 510 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application program required by a function (such as a sound playback function, an image playback function, etc.); The data created using the power supply circuit 100 and the like. In addition, the memory 510 may include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart memory card (Smart Media Card, SMC), secure digital (Secure Digital, SD) card, flash memory card (Flash Card), At least one disk storage device, flash memory device, or other non-volatile solid-state storage device.

The memory 510 may be an external memory and/or an internal memory of the power supply circuit 100 . Further, the storage 510 may be a physical storage, such as a memory stick, a TF card (Trans-flash Card), and the like.

The program codes and various data in the memory 510 may be stored in a computer-readable storage medium if implemented in the form of software function units and sold or used as an independent product. Based on this understanding, the present application implements all or part of the processes in the methods of the above embodiments, such as the load identification method of the power supply circuit, which can also be completed by instructing related hardware through computer programs, and the computer programs can be stored in computer-readable storage media. Among them, when the computer program is executed by the processor 520, the steps of the above-mentioned various method embodiments can be realized. Wherein, the computer program includes computer program code, and the computer program code may be in the form of source code, object code, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying computer program code, recording medium, U disk, removable hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), etc.

The embodiment of the present application also provides a power supply device. The power supply device includes a DC power supply 200, a DC interface, a load interface, and the power supply circuit 100 as before. The DC terminal of the inverter circuit 10 in the power supply circuit 100 communicates with the DC power supply 200 through the DC interface. The AC end of the inverter circuit 10 is connected to the load 300 through the load interface.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application without limitation. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be Make modifications or equivalent replacements without departing from the spirit and scope of the technical solutions of the present application.

Claims (10)

1. A load identification method of a power supply circuit, wherein the power supply circuit includes an inverter circuit, a dc terminal of the inverter circuit is used for connecting a dc power supply, an ac terminal of the inverter circuit is used for connecting a load, the load identification method includes:

acquiring the input power of a direct-current end of the inverter circuit;

comparing the input power with a preset power threshold, and confirming that the alternating-current end of the inverter circuit is connected with the load when the input power is larger than the preset power threshold; the preset power threshold is the no-load power of the direct-current end of the inverter circuit when the inverter circuit is in an no-load state.

2. The load identification method according to claim 1, wherein before the input power of the dc terminal of the inverter circuit is obtained, the load identification method further comprises:

and when the inverter circuit is in an idle state, acquiring input current and input voltage of a direct-current end of the inverter circuit, and calculating the preset power threshold according to the input current and the input voltage.

3. The load identification method according to claim 1, wherein upon confirming that the ac terminal of the inverter circuit is connected with a load, the load identification method further comprises:

obtaining output current and output voltage of an alternating-current end of the inverter circuit;

calculating the output power of the alternating-current end of the inverter circuit according to the output current and the output voltage, and generating an inversion control instruction according to the output power, wherein the inversion control instruction comprises inversion control information, and the inversion control instruction is used for instructing the inverter circuit to perform power adjustment according to the inversion control information.

4. The load identification method of claim 1, wherein the load identification method further comprises:

and when the input power is smaller than or equal to the preset power threshold value, confirming that the inverter circuit is in an idle state, and generating an inversion stopping instruction, wherein the inversion stopping instruction is used for indicating the inverter circuit to stop working.

5. A power supply circuit, the power supply circuit comprising: the inverter circuit and the main control circuit; the direct current end of inverter circuit is used for connecting direct current power supply, inverter circuit's alternating current end is used for connecting the load, main control circuit with inverter circuit connects, main control circuit is used for:

acquiring the input power of a direct-current end of the inverter circuit;

comparing the input power with a preset power threshold, and confirming that the alternating-current end of the inverter circuit is connected with the load when the input power is larger than the preset power threshold; the preset power threshold is the no-load power of the direct-current end of the inverter circuit when the inverter circuit is in an no-load state.

6. The power supply circuit of claim 5, wherein the inverter circuit comprises:

the input end of the DC/DC conversion unit is connected with the direct current power supply and is used for carrying out direct current-direct current conversion on direct current output by the direct current power supply and then outputting the direct current;

the input end of the AC/DC conversion unit is connected with the output end of the DC/DC conversion unit, the output end of the AC/DC conversion unit is used for being connected with the load, and the AC/DC conversion unit is used for carrying out AC/DC conversion on the direct current output by the DC/DC conversion unit and then outputting the direct current.

7. The power supply circuit of claim 5, wherein the master circuit comprises:

the first sampling unit is arranged at the direct-current end of the inverter circuit, and is used for sampling current and voltage of the direct-current end of the inverter circuit and obtaining the input power according to a sampling result.

8. The power supply circuit of claim 7, wherein the first sampling unit comprises: a first sampling resistor and a first voltage sampler; the first sampling resistor is connected to the direct current end of the inverter circuit, and the first voltage sampler is connected with the first sampling resistor.

9. The power supply circuit of claim 5, wherein the master circuit further comprises:

the second sampling unit is used for sampling voltage and current of an alternating-current end of the inverter circuit and generating output power according to a sampling result;

and the control unit is connected with the second sampling unit and is used for receiving the output power, generating an inversion control instruction according to the output power when the alternating current end of the inversion circuit is confirmed to be connected with a load, wherein the inversion control instruction comprises inversion control information, and the inversion control instruction is used for instructing the inversion circuit to perform power adjustment according to the inversion control information.

10. An electronic device comprising power supply circuitry, a memory storing executable instructions for the processor, and a processor for executing the executable instructions to perform the steps of the load identification method of any of claims 1-4.

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