Load detection device and method, unmanned device charging system

Abstract

Embodiments of the present invention disclose a load detection device and method, as well as an unmanned device charging system. The device includes: a power supply circuit for supplying power to a load; a voltage acquisition circuit configured to acquire a voltage signal from the power supply circuit; a first controllable switch disposed between the voltage acquisition circuit and the power supply circuit; and a processor configured to: control the first controllable switch to close; acquire the voltage signal acquired by the voltage acquisition circuit; and determine the state of the power supply circuit based on fluctuations in the voltage signal. Thus, the load detection device of the embodiment of the present invention can not only detect the presence of a short circuit, but also determine whether a load is connected, reducing the risk of component damage due to high current in the event of a load short circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of load detection, and in particular to a load detection device and method, and an unmanned device charging system. Background Art

[0002] The load detection circuit refers to a circuit that detects whether the connection section of the power supply device is connected to a load. The load refers to the electrical equipment connected to the two ends of the power supply in the circuit, which is divided into inductive load, resistive load, capacitive load, etc. At present, for the load detection circuit connected to the power supply device, after the external connector is connected to the load, the load can be equivalent to a resistor, and as long as the resistance of the voltage divider resistor is much greater than the resistance of the load equivalent resistor, the voltage value or range detected by the central processing unit (CPU) can be determined by allocating the voltage divider resistor. When the load is not connected, the LOAD pin of the CPU has no voltage or is very low. At this time, it can be determined that the external load is not connected, and the program does not allow the power on. However, when the external load is short-circuited or the load interface and the power interface are reversely inserted to cause a physical short circuit, it will also cause an erroneous power on operation. At this time, there is a risk of burning the circuit board of the power supply device due to the large current, and more seriously, it may cause a fire. Summary of the Invention

[0003] The purpose of the embodiments of the present invention is to provide a load detection device and method, and an unmanned device charging system, so as to solve the problem that the existing load detection circuit is prone to damage to components when the load is short-circuited.

[0004] To achieve the above objectives, a first aspect of an embodiment of the present invention provides a load detection device, comprising:

[0005] Power supply circuit, used to supply power to the load;

[0006] A voltage acquisition circuit is configured to acquire a voltage signal from a power supply circuit;

[0007] A first controllable switch is provided between the voltage acquisition circuit and the power supply circuit; and

[0008] The processor is configured to:

[0009] controlling the first controllable switch to close;

[0010] Acquiring a voltage signal collected by a voltage collection circuit;

[0011] The state of the power supply circuit is determined based on the fluctuation of the voltage signal.

[0012] In an embodiment of the present invention, the processor is configured to determine the state of the power supply circuit according to the fluctuation of the voltage signal, including: the processor is configured to:

[0013] Determine the fluctuation pattern of voltage signal;

[0014] Compare the fluctuation pattern with the preset fluctuation pattern;

[0015] When the fluctuation pattern does not match the preset fluctuation pattern, it is determined that a short circuit occurs in the power supply circuit; when the fluctuation pattern matches the preset fluctuation pattern, it is determined that no short circuit occurs in the power supply circuit.

[0016] In an embodiment of the present invention, the power supply circuit includes a second controllable switch for controlling the on / off of the power supply circuit, and the processor is further configured to:

[0017] When it is determined that no short circuit occurs in the power supply circuit, the second controllable switch is controlled to be closed.

[0018] In an embodiment of the present invention, the processor is configured to obtain a voltage signal collected by the voltage collection circuit, including:

[0019] The processor is configured to obtain a voltage signal collected by the voltage collection circuit within a preset time.

[0020] In an embodiment of the present invention, the preset fluctuation law is determined by the following formula:

[0021] U=E(1-e -t / RC );

[0022] Wherein, U is the real-time voltage value of the load capacitor of the load, E is the steady-state voltage value of the load capacitor, C is the capacitance value of the load capacitor, and t is the preset time.

[0023] In an embodiment of the present invention, the voltage acquisition circuit includes a first resistor, a second resistor and a third resistor; one end of the first resistor is electrically connected to one end of the second resistor, and the other end of the first resistor is electrically connected to the power supply circuit through a first controllable switch; the other end of the second resistor is grounded, and the node between the first resistor and the second resistor is electrically connected to the processor through the third resistor.

[0024] In an embodiment of the present invention, the voltage acquisition circuit further includes a resistance component connected in parallel with the first resistor and the second resistor connected in series; the resistance component includes a fourth resistor and a fifth resistor connected in series.

[0025] In an embodiment of the present invention, the processor is further configured to:

[0026] The charging time of the load is controlled by adjusting the resistance value of the resistor component.

[0027] In an embodiment of the present invention, the power supply circuit also includes a power supply, a power connector and a load connector; the positive pole of the power supply is electrically connected to the positive pole of the power connector, the negative pole of the power supply is electrically connected to the negative pole of the power connector, the positive pole of the power connector is electrically connected to the positive pole of the load connector, the negative pole of the power connector is electrically connected to the negative pole of the load connector, and the second controllable switch is arranged between the negative pole of the power supply and the negative pole of the power connector.

[0028] A second aspect of an embodiment of the present invention provides an unmanned device charging system, comprising an unmanned device, a power supply device, and the above-mentioned load detection device.

[0029] A third aspect of an embodiment of the present invention provides a load detection method, including:

[0030] Controlling the first controllable switch to close to conduct the power supply circuit and the voltage collection circuit;

[0031] Acquire a voltage signal collected by a voltage collection circuit within a preset time;

[0032] The state of the power supply circuit is determined based on the fluctuation of the voltage signal.

[0033] In an embodiment of the present invention, determining the state of the power supply circuit according to the fluctuation of the voltage signal includes:

[0034] Determine the fluctuation pattern of the voltage signal and compare the fluctuation pattern with a preset fluctuation pattern;

[0035] In the case where the fluctuation pattern does not match the preset fluctuation pattern, it is determined that a short circuit occurs in the power supply circuit;

[0036] When the fluctuation pattern matches the preset fluctuation pattern, it is determined that no short circuit occurs in the power supply circuit.

[0037] In an embodiment of the present invention, it further includes:

[0038] When it is determined that no short circuit occurs in the power supply circuit, the second controllable switch provided in the power supply circuit is controlled to be closed.

[0039] Through the above technical solution, a first controllable switch is provided between the power supply circuit and the voltage acquisition circuit. The processor controls the first controllable switch to close, acquires the voltage signal collected by the voltage acquisition circuit, and determines the power supply circuit status based on fluctuations in the voltage signal. In this way, the load detection device of this embodiment of the present invention can not only detect the presence of a short circuit but also determine whether a load is connected, reducing the risk of component damage caused by high current in the event of a load short circuit.

[0040] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present invention, but do not constitute a limitation of the embodiments of the present invention. In the accompanying drawings:

[0042] Figure 1 is a structural diagram of a load detection device provided by an embodiment of the present invention;

[0043] Figure 2 is a structural diagram of a load detection device provided by another embodiment of the present invention;

[0044] Figure 3 is a schematic diagram of the circuit structure of a load detection device provided by an embodiment of the present invention;

[0045] Figure 4 It is a flow chart of the load detection method provided by an embodiment of the present invention.

[0046] Description of Reference Numerals

[0047] 1 Power supply circuit 11 Second controllable switch

[0048] 12 Power supply 13 Power connector

[0049] 14 Load connector 15 Load

[0050] 2 Voltage acquisition circuit 21 First resistor

[0051] 22 Second resistor 23 Third resistor

[0052] 24 Fourth resistor 25 Fifth resistor

[0053] 3 First controllable switch 4 Processor DETAILED DESCRIPTION

[0054] The following describes the specific implementation of the embodiment of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the embodiment of the present invention and is not used to limit the embodiment of the present invention.

[0055] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0056] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0057] See also Figure 1 , Figure 1 FIG is a schematic diagram of the structure of a load detection device provided by an embodiment of the present invention. Figure 1 As shown, an embodiment of the present invention provides a load detection device, which may include:

[0058] Power supply circuit 1, used to supply power to the load;

[0059] The voltage acquisition circuit 2 is configured to acquire a voltage signal from the power supply circuit 1;

[0060] A first controllable switch 3 is provided between the voltage acquisition circuit 2 and the power supply circuit 1; and

[0061] Processor 4 is configured as follows:

[0062] Controlling the first controllable switch 3 to close;

[0063] Acquire the voltage signal collected by the voltage collection circuit 2;

[0064] The state of the power supply circuit 1 is determined according to the fluctuation of the voltage signal.

[0065] In an embodiment of the present invention, the power supply circuit 1 is a circuit for supplying power to a load. The load in the embodiment of the present invention is a capacitive load. A capacitive load refers to a load with capacitance at the input and output ends of a power supply. A capacitive load can be equivalent to a resistor and a capacitor connected in parallel. The equivalent resistor and capacitor can be referred to as a load resistor and a load capacitor. The power supply circuit 1 may include a circuit formed in series by a power supply, a second controllable switch, and a load connector for connecting a load. When the load connector is connected to the load and the second controllable switch is closed, the power supply circuit 1 forms a path, and the load capacitor equivalent to the load is connected to the DC voltage source, and the load capacitor is charged.

[0066] In an embodiment of the present invention, the voltage acquisition circuit 2 is electrically connected to the power supply circuit 1 and can acquire a voltage signal from the power supply circuit 1. The collected voltage signal may include a voltage value, a voltage fluctuation, etc. The first controllable switch 3 is arranged between the voltage acquisition circuit 2 and the power supply circuit 1. When the first controllable switch 3 is closed, the power supply circuit 1 and the voltage acquisition circuit 2 form a path, and the voltage acquisition circuit 2 can acquire the voltage signal of the power supply circuit 1; when the first controllable switch 3 is disconnected, the power supply circuit 1 and the voltage acquisition circuit 2 are not conductive, and at this time, the voltage acquisition circuit 2 cannot acquire the voltage signal of the power supply circuit 1. In an example, the first controllable switch may include but is not limited to a triode, a MOS tube, an insulated gate bipolar transistor (IGBT), etc.

[0067] In an embodiment of the present invention, the processor 4 can control the closure of the first controllable switch 3 to connect the power supply circuit 1 and the voltage acquisition circuit 2, thereby obtaining the voltage signal collected by the voltage acquisition circuit 2 and determining the status of the power supply circuit 1 based on the fluctuation of the voltage signal. The load capacitance equivalent to the load undergoes a dynamic process, and the voltage of the power supply circuit 1 exhibits a certain fluctuation pattern during the period when the first controllable switch 3 is closed. In the absence of a load or a short circuit, the voltage does not exhibit a certain fluctuation pattern even when the first controllable switch 3 is closed. However, in the absence of a short circuit, the voltage exhibits a certain fluctuation pattern when the first controllable switch 3 is closed. In one example, the voltage signal fluctuates within a certain period of time while the first controllable switch 3 is closed, i.e., while the power supply circuit 1 and the voltage acquisition circuit 2 form a connection. The processor 4 compares this fluctuation pattern with a preset fluctuation pattern. If the fluctuation pattern does not match the preset fluctuation pattern, the processor determines that a short circuit has occurred in the power supply circuit 1; if the fluctuation pattern matches the preset fluctuation pattern, the processor determines that a short circuit has not occurred in the power supply circuit 1. In another example, if the voltage signal does not fluctuate within a certain period of time while the first controllable switch 3 is closed, i.e., while the power supply circuit 1 and the voltage acquisition circuit 2 form a connection, the processor 4 can determine that a short circuit has occurred in the power supply circuit 1. In the event of a short circuit in the power supply circuit 1 , the processor 4 may control the second controllable switch of the power supply circuit 1 to be disconnected, so as to stop charging the load and protect the components in the circuit.

[0068] This embodiment of the present invention disposes a first controllable switch 3 between the power supply circuit 1 and the voltage acquisition circuit 2, enabling the processor 4 to control the closing of the first controllable switch 3, obtain the voltage signal collected by the voltage acquisition circuit 2, and determine the state of the power supply circuit 1 based on the fluctuations of the voltage signal. In this way, the load detection device of this embodiment of the present invention can not only detect the presence of a short circuit but also determine whether a load is connected, reducing the risk of component damage caused by high current in the event of a load short circuit.

[0069] In an embodiment of the present invention, the processor 4 is configured to determine the state of the power supply circuit 1 according to the fluctuation of the voltage signal, including: the processor 4 may be configured to:

[0070] Determine the fluctuation pattern of voltage signal;

[0071] Compare the fluctuation pattern with the preset fluctuation pattern;

[0072] In the case that the fluctuation pattern does not match the preset fluctuation pattern, it is determined that a short circuit occurs in the power supply circuit 1 .

[0073] Specifically, when there is no short circuit in the power supply circuit 1, the voltage acquisition circuit 2 can collect a fluctuating voltage signal during the period when the first controllable switch 2 is closed. In the case of a short circuit in the power supply circuit 1, the voltage signal collected by the voltage acquisition circuit 2 tends to be steady-state after the first controllable switch 2 is closed, and there will be no fluctuating voltage signal. Therefore, the processor 4 can determine the state of the power supply circuit by comparing the fluctuation pattern of the voltage signal with the preset fluctuation pattern. In an embodiment of the present invention, when the fluctuation pattern does not match the preset fluctuation pattern, for example, when the voltage signal received by the processor 4 tends to be stable, the processor 4 can determine that a short circuit has occurred in the power supply circuit 1. The processor 4 further controls the disconnection of the power supply circuit 1 to avoid a situation where the current in the power supply circuit 1 is large due to a short circuit, the circuit board is burned, and the circuit components are damaged.

[0074] In an embodiment of the present invention, the processor may be further configured to:

[0075] When the fluctuation pattern matches the preset fluctuation pattern, it is determined that no short circuit occurs in the power supply circuit.

[0076] Specifically, when the fluctuation pattern matches the preset fluctuation pattern, for example, the voltage signal received by the processor 4 decreases from a high point to a low point within 1S, and the fluctuation process from a high point to a low point matches the preset fluctuation pattern, the processor 4 can determine that the power supply circuit 1 is not short-circuited. In one example, when the power supply circuit 1 is not short-circuited, the fluctuation pattern of the voltage signal is that the power supply voltage at the moment the power supply circuit 1 is turned on slowly decreases to a preset voltage value within a set time t. If the voltage signal at the moment the power supply circuit 1 is turned on suddenly changes to a set value, it also does not match the preset fluctuation pattern. The processor 4 further controls the closure of the power supply circuit 1. In this way, it can ensure that the load is charged when the power supply circuit 1 is not short-circuited, thereby improving the safety of the power supply circuit 1 charging the load.

[0077] In an embodiment of the present invention, the processor 4 is configured to obtain the voltage signal collected by the voltage collection circuit 2, which may include:

[0078] The processor 4 is configured to obtain the voltage signal collected by the voltage collection circuit 2 within a preset time.

[0079] Specifically, the load capacitance equivalent to the load undergoes a dynamic process, and the voltage of the power supply circuit 1 exhibits a certain fluctuation pattern during the period when the first controllable switch 3 is closed. The processor 4 can determine whether the power supply circuit 1 is short-circuited by detecting the fluctuation pattern of the voltage signal during a preset period of time when the first controllable switch 3 is closed. The preset period can be a relatively short period of time, such as 1 second or 500 milliseconds. The voltage signal obtained by the processor 4 may fluctuate or be a stable voltage signal.

[0080] In an embodiment of the present invention, the preset fluctuation law is determined by the following formula:

[0081] U=E(1-e -t / RC );

[0082] Wherein, U is the real-time voltage value of the load capacitor of the load, E is the steady-state voltage value of the load capacitor, C is the capacitance value of the load capacitor, and t is the preset time.

[0083] Specifically, when the power supply circuit 1 is turned on, due to the presence of capacitance in the load, the voltage to which the load capacitor can be charged is the voltage divided by the series connection of the resistor of the voltage acquisition circuit 2 and the load resistor, and the charging time is determined by the R of the power supply circuit 1 and the voltage acquisition circuit and the load capacitance C. Therefore, the above formula is satisfied. At this time, there is an RC parameter, and the load capacitance is known and constant. However, R is adjustable, and the charging time of the load capacitance can be adjusted by adjusting the resistance of the voltage acquisition circuit 2 until the load capacitance is charged to the steady-state voltage. When the power supply circuit 1 is short-circuited, the voltage of the power supply circuit 1 is close to the power supply voltage and there is no fluctuation. When the power supply circuit 1 is not short-circuited, the fluctuation pattern of the voltage of the power supply circuit 1 conforms to the fluctuation pattern of the above formula. In this way, by comparing the fluctuation pattern of the voltage signal with the above formula, it can be determined whether the power supply circuit 1 is short-circuited, thereby improving the safety of the power supply circuit 1 charging the load.

[0084] In addition, when the voltage of the voltage acquisition circuit 2 is detected to be 0V when the power supply circuit 1 is turned on, it is determined that the power supply circuit 1 is not connected to a load. At this time, the processor 4 may not allow the power supply circuit 1 to be turned on.

[0085] Through the description of the above principles, the design process of the short-circuit detection circuit of the corresponding specific load can be basically deduced: the load capacitance value C is known from the design perspective; a suitable voltage acquisition circuit 2 is given to test the load equivalent resistance; the voltage of the voltage acquisition circuit 2 is detected, and when the voltage does not change, it is determined that a steady state is reached; in the steady state, the voltage divider value of the equivalent resistance of the load is measured, and the resistance value of the load is calculated based on the resistance of the voltage acquisition circuit 2. The resistance of the corresponding voltage acquisition circuit 2 is calculated according to the above formula, so that the capacitor is charged within the preset time, ensuring that the CPU can accurately detect the charging process of the load during this period, so as to make it clearly distinguishable from the detection characteristics when the power supply circuit 1 is short-circuited.

[0086] See also Figure 2 , Figure 2 FIG. 1 is a schematic diagram of the structure of a load detection device provided by another embodiment of the present invention. Figure 2 As shown, an embodiment of the present invention provides a load detection device, the power supply circuit 1 may include a second controllable switch 11 for controlling the on / off of the power supply circuit 1, and the processor 4 may be further configured to:

[0087] When it is determined that no short circuit occurs in the power supply circuit 1 , the second controllable switch 11 is controlled to be closed.

[0088] Specifically, the second controllable switch 11 of the power supply circuit 1 can be disposed between the negative pole of the power supply and the negative pole of the power connector. When the second controllable switch 11 is closed, the power supply circuit 1 is turned on, the positive pole of the power supply is electrically connected to the positive pole of the load via the connector, and the negative pole of the power supply is electrically connected to the negative pole of the load via the connector, and the power supply begins to charge the load. In embodiments of the present invention, upon determining that the power supply circuit 1 is not short-circuited, the processor 4 controls the conduction of the power supply circuit 1, thereby improving the safety of the power supply circuit 1 in charging the load.

[0089] See also Figure 3 , Figure 3 FIG. 1 is a schematic diagram of the circuit structure of the load detection device provided by an embodiment of the present invention. Figure 3 As shown, in an embodiment of the present invention, the voltage acquisition circuit 2 may include a first resistor 21, a second resistor 22 and a third resistor 23; one end of the first resistor 21 is electrically connected to one end of the second resistor 22, and the other end of the first resistor 21 is electrically connected to the power supply circuit 1 through the first controllable switch 3; the other end of the second resistor 22 is grounded, and the node between the first resistor 21 and the second resistor 22 is electrically connected to the processor 4 through the third resistor 23.

[0090] Examples of the processor 4 may include, but are not limited to, a central processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, and the like.

[0091] For example, in one example, the processor 4 may be a CPU, the first resistor 21 and the second resistor 22 may be used as voltage divider resistors, and the third resistor 23 may be used as a current limiting resistor to ensure that the LOAD voltage value of the CPU is lower than the voltage value it can withstand.

[0092] In an embodiment of the present invention, the voltage acquisition circuit 2 further includes a resistor assembly connected in parallel with the first resistor 21 and the second resistor 22 connected in series. The resistor assembly may include multiple resistors connected in series. The resistor assembly can function as a pre-charge resistor, providing a pre-charge current to the load, and can also limit the voltage at the pin of the processor 4. In one example, the voltage acquisition circuit 2 further includes a fourth resistor 24 and a fifth resistor 25 connected in series. One end of the fourth resistor 24 is electrically connected to one end of the fifth resistor 25, and the other end of the fourth resistor 24 is electrically connected to the power supply circuit 1. The other end of the fifth resistor 25 is grounded.

[0093] Specifically, the fourth resistor 24 and the fifth resistor 25 are connected in series to form a resistor assembly, which is connected in parallel with the first resistor 21 and the second resistor 22 connected in series. The resistor assembly can be used as a pre-charging resistor. The pre-charging resistor is connected in series with the charging circuit during the pre-charging process to limit the size of the pre-charging current. This prevents the large charging current generated by the short circuit at the moment of power-on from damaging the power device.

[0094] In an embodiment of the present invention, before the second controllable switch 11 is closed, the CPU preferentially controls the closing of the first controllable switch 3. At this moment, the current flowing at the moment of conduction is determined by the resistance of the voltage acquisition circuit 2, which is the resistance formed by the voltage divider formed by the first resistor 21 and the second resistor 22, and the pre-charge resistor formed by the fourth resistor 24 and the fifth resistor 25 in parallel. The reason for using two resistors in parallel here is that the first resistor 21 and the second resistor 22 are connected in series. The CPU collects the voltage at the node between the first resistor 21 and the second resistor 22. Because the voltage at this node can be large, the first resistor 21 and the second resistor 22 are connected in series to ensure that the voltage on the CPU pin does not exceed the maximum voltage it can withstand. The purpose of the fourth resistor 24 and the fifth resistor 25 being connected in series is to eliminate the resistance limit of the first resistor 21 and the second resistor 22 and provide the main pre-charge current for the load.

[0095] In an embodiment of the present invention, the processor 4 may also be configured to:

[0096] The charging time of the load is controlled by adjusting the resistance value of the resistor component.

[0097] Specifically, when the power supply circuit 1 is turned on, due to the presence of capacitance in the load, the voltage to which the load capacitor can be charged is the voltage divided by the series connection of the resistor of the voltage acquisition circuit 2 and the load resistor. The charging time is determined by the resistance R external to the power supply circuit 1 and the load, and the load capacitance C. In one example, the resistance R external to the load can be the resistance value of the first resistor 21, the second resistor 22, and the resistor assembly connected in parallel. At this point, an RC parameter exists, and the load capacitance is known and constant. However, R is adjustable. The charging time of the load capacitor can be adjusted by adjusting the resistance of the voltage acquisition circuit 2 until the load capacitance reaches a steady-state voltage. When the power supply circuit 1 is short-circuited, the voltage of the power supply circuit 1 is close to the power supply voltage and does not fluctuate. When the power supply circuit 1 is not short-circuited, the fluctuation pattern of the voltage of the power supply circuit 1 conforms to or matches the fluctuation pattern defined by the above formula. Therefore, whether the fluctuation pattern of the voltage signal conforms to or matches the fluctuation pattern defined by the above formula can be used to determine whether the power supply circuit 1 is short-circuited, thereby improving the safety of charging the load by the power supply circuit 1.

[0098] In an embodiment of the present invention, the power supply circuit 1 may further include a power supply 12, a power connector 13 and a load connector 14; the positive pole of the power supply 12 is electrically connected to the positive pole of the power connector 13, the negative pole of the power supply 12 is electrically connected to the negative pole of the power connector 13, the positive pole of the power connector 13 is electrically connected to the positive pole of the load connector 14, the negative pole of the power connector 13 is electrically connected to the negative pole of the load connector 14, and the second controllable switch 11 is arranged between the negative pole of the power supply 12 and the negative pole of the power connector 13.

[0099] Specifically, the power supply circuit 1 is formed into a loop by a second controllable switch 11, a power supply 12, a power connector 13 and a load connector 14. The second controllable switch 11 is arranged between the negative pole of the power supply 12 and the negative pole of the power connector 13. When the second controllable switch 11 is disconnected, the power supply circuit 1 is not conductive and the load cannot be charged. When the second controllable switch 11 is closed, the power supply circuit 1 is conductive and the load can be charged. In this way, the load can be charged when the load detection device detects that the power supply circuit 1 is not short-circuited and the load is connected, thereby reducing the risk of component damage due to large current when the load is short-circuited. In addition, the circuit of the embodiment of the present invention is of great help for short-circuit detection before power-on, and has low cost and a wide range of applications. A suitable RC constant can be matched according to the characteristics of each load.

[0100] by Figure 3Taking the circuit structure of the load detection device shown in FIG. as an example, in one embodiment, the circuit structure of the load detection device of the present invention may include: a power supply circuit 1, a voltage acquisition circuit 2, a first controllable switch 3, and a processor 4. The first controllable switch 3 is disposed between the power supply circuit 1 and the voltage acquisition circuit 2. The power supply circuit 1 includes a second controllable switch 11. The processor 4 is electrically connected to the voltage acquisition circuit 2, the first controllable switch 3, and the second controllable switch 11.

[0101] The power supply circuit 1 includes a power supply 12, a power connector 13 and a load connector 14; the positive pole of the power supply 12 is electrically connected to the positive pole of the power connector 13, the negative pole of the power supply 12 is electrically connected to the negative pole of the power connector 13, the positive pole of the power connector 13 is electrically connected to the positive pole of the load connector 14, the negative pole of the power connector 13 is electrically connected to the negative pole of the load connector 14, and the second controllable switch 11 is arranged between the negative pole of the power supply 12 and the negative pole of the power connector 13.

[0102] Specifically, the power supply circuit 1 is formed by a second controllable switch 11, a power supply 12, a power connector 13, a load connector 14, and a load 15. The second controllable switch 11 is disposed between the negative electrode of the power supply 12 and the negative electrode BAT- of the power connector 13. The negative electrode BAT- of the power connector 13 is connected to the negative electrode PACK- of the load connector 14. The negative electrode PACK- of the load connector 14 is connected to one end of the load 15. The other end of the load 15 is connected to the positive electrode PACK+ of the load connector 14. The positive electrode PACK+ of the load connector 14 is connected to the positive electrode BAT+ of the power connector 13. The positive electrode BAT+ of the power connector 13 is connected to the positive electrode of the power supply 12. When the second controllable switch 11 is disconnected, the power supply circuit 1 is not conductive and cannot charge the load 15. When the second controllable switch 11 is closed, the power supply circuit 1 is conductive and can charge the load 15. In this way, load 15 can be charged only after the load detection device detects that power supply circuit 1 is not short-circuited and load 15 is connected, thereby reducing the risk of component damage caused by large current in the event of a short circuit in load 15. In addition, the circuit of the embodiment of the present invention is very helpful for short-circuit detection before power-on, is low-cost, has a wide range of applications, and can match the appropriate RC constant according to the characteristics of each load.

[0103] The voltage acquisition circuit 2 includes a first resistor 21, a second resistor 22, and a third resistor 23. One end of the first resistor 21 is electrically connected to one end of the second resistor 22, and the other end of the first resistor 21 is electrically connected to the power supply circuit 1 via a first controllable switch 3. The other end of the second resistor 22 is grounded, and the node between the first resistor 21 and the second resistor 22 is electrically connected to the processor 4 via the third resistor 23. In one example, the processor 4 may be a CPU, the first resistor 21 and the second resistor 22 may be voltage divider resistors, and the third resistor 23 may be a current limiting resistor used to ensure that the voltage value of the CPU's LOAD pin is lower than the voltage value it can withstand.

[0104] The voltage acquisition circuit also includes a resistor component, which is connected in parallel with the first resistor 21 and the second resistor 22 connected in series. In one example, the resistor component may include a fourth resistor 24 and a fifth resistor 25 connected in series. One end of the fourth resistor 24 is electrically connected to one end of the fifth resistor 25, and the other end of the fourth resistor 24 is electrically connected to the power supply circuit 1; the other end of the fifth resistor 25 is grounded. The fourth resistor 24 and the fifth resistor 25 are connected in series to form a resistor component, which is connected in parallel with the first resistor 21 and the second resistor 22 connected in series. The resistor component can be used as a pre-charging resistor. The pre-charging resistor is a pre-charging resistor connected in series with the charging circuit during the pre-charging process to limit the size of the pre-charging current and avoid the large charging current caused by the short circuit at the moment of power-on to damage the power device.

[0105] In an embodiment of the present invention, before the second controllable switch 11 is closed, the CPU preferentially controls the closing of the first controllable switch 3. At this moment of conduction, the current is determined by the resistance of the voltage acquisition circuit 2, which is the resistance formed by the voltage divider formed by the first resistor 21 and the second resistor 22, and the pre-charge resistor formed by the fourth resistor 24 and the fifth resistor 25 in parallel. The reason for using two resistors in parallel here is that the first resistor 21 and the second resistor 22 are connected in series. The CPU collects the voltage at the node between the first resistor 21 and the second resistor 22. Because the voltage at this node may be large, the first resistor 21 and the second resistor 22 are connected in series to ensure that the voltage of the CPU pin LOAD does not exceed the maximum voltage it can withstand. The purpose of the fourth resistor 24 and the fifth resistor 25 in series is to eliminate the resistance limit of the first resistor 21 and the second resistor 22 and provide the main pre-charge current for the load.

[0106] The processor 4 can control the closing of the first controllable switch 3 so that the power supply circuit 1 and the voltage acquisition circuit 2 form a path, thereby obtaining the voltage signal collected by the voltage acquisition circuit 2, and determining the state of the power supply circuit 1 according to the fluctuation of the voltage signal. There is a dynamic process for the load capacitance equivalent to the load, and the voltage of the power supply circuit 1 has a certain fluctuation pattern during the period when the first controllable switch 3 is closed. In the absence of load or short circuit, even if the first controllable switch 3 is closed, the voltage signal collected by the voltage acquisition circuit 2 will not produce a fluctuation pattern. In the absence of a short circuit, the first controllable switch 3 is closed, and the voltage signal collected by the voltage acquisition circuit 2 will produce a certain fluctuation pattern. Figure 3 For example, when the power supply circuit 1 is not short-circuited, the voltage value detected by the processor 4 will slowly decrease from the power supply voltage (i.e. BAT+) at the beginning of the conduction to the preset voltage value V 预设值 , that is, the voltage at point A1 (BAT+) - the real-time voltage value of the load capacitor U = the preset voltage value V 预设值 , instead of suddenly changing to V 预设值 . Therefore, the processor 4 (i.e., the CPU) needs to continuously monitor the voltage value at point B1 at the LOAD pin within a preset time t. According to the principle of voltage division by series resistors, the fluctuation pattern of point B1 can reflect the voltage fluctuation pattern of point A1 in a certain proportion, thereby judging whether the voltage value of the power supply circuit 1 conforms to or matches this fluctuation pattern. In one example, the first controllable switch 3 is closed, that is, within a certain period of time when the power supply circuit 1 and the voltage acquisition circuit 2 form a path, the voltage signal fluctuates. The processor 4 compares the fluctuation pattern with the preset fluctuation pattern. If the fluctuation pattern does not match the preset fluctuation pattern, it is determined that a short circuit has occurred in the power supply circuit 1; if the fluctuation pattern matches the preset fluctuation pattern, it is determined that no short circuit has occurred in the power supply circuit 1. In another example, the first controllable switch 3 is closed, that is, within a certain period of time when the power supply circuit 1 and the voltage acquisition circuit 2 form a path, the voltage signal does not fluctuate. At this time, the processor 4 can determine that a short circuit has occurred in the power supply circuit 1. In the case of a short circuit in the power supply circuit 1, the processor 4 can control the second controllable switch of the power supply circuit 1 to be disconnected, and not charge the load to protect the components in the circuit.

[0107] This embodiment of the present invention disposes a first controllable switch 3 between the power supply circuit 1 and the voltage acquisition circuit 2, enabling the processor 4 to control the closing of the first controllable switch 3, obtain the voltage signal collected by the voltage acquisition circuit 2, and determine the state of the power supply circuit 1 based on the fluctuations of the voltage signal. In this way, the load detection device of this embodiment of the present invention can not only detect the presence of a short circuit but also determine whether a load is connected, reducing the risk of component damage caused by high current in the event of a load short circuit.

[0108] It should be noted that the embodiments of the present invention are not limited to the above examples, and may also be other circuit structures capable of detecting the short-circuit state and connection state of a load.

[0109] An embodiment of the present invention further provides an unmanned device charging system, which may include: an unmanned device, a power supply device, and the above-mentioned load detection device.

[0110] In embodiments of the present invention, unmanned devices may include, but are not limited to, drones or unmanned vehicles. A power supply device is electrically connected to the unmanned device for supplying power to the unmanned device. A load detection device is electrically connected to the unmanned device for detecting whether the unmanned device is short-circuited and whether the unmanned device is connected. The load detection device in the above embodiment employs a first controllable switch disposed between the power supply circuit and the voltage acquisition circuit. A processor controls the closing of the first controllable switch to acquire a voltage signal collected by the voltage acquisition circuit within a preset time period, and determines the state of the power supply circuit based on the fluctuations in the voltage signal. In one example, the fluctuation pattern of the voltage signal is compared with a preset fluctuation pattern. If the fluctuation pattern does not match the preset pattern, a short circuit is determined in the power supply circuit. In this case, the processor can control the power supply circuit to disconnect and not charge the unmanned device. If the fluctuation pattern matches the preset pattern, a short circuit is determined in the power supply circuit. In this case, the processor can control the closing of the power supply circuit to charge the unmanned device. Thus, the load detection device in embodiments of the present invention can not only detect the presence of a short circuit but also determine whether a load is connected, reducing the risk of component damage caused by high current when a load short circuit occurs.

[0111] See also Figure 4 , Figure 4 FIG is a flow chart of the load detection method provided by an embodiment of the present invention. Figure 4 As shown, an embodiment of the present invention further provides a load detection method, which includes the following steps:

[0112] Step S41: controlling the first controllable switch to be closed to conduct the power supply circuit and the voltage acquisition circuit;

[0113] Step S42: acquiring a voltage signal collected by a voltage collection circuit within a preset time;

[0114] Step S43: Determine the state of the power supply circuit according to the fluctuation of the voltage signal.

[0115] In an embodiment of the present invention, a first controllable switch is disposed between the voltage acquisition circuit and the power supply circuit. The processor can control the first controllable switch to close, thereby connecting the voltage acquisition circuit and the power supply circuit, thereby acquiring a voltage signal collected by the voltage acquisition circuit within a preset time, and determining the state of the power supply circuit based on fluctuations in the voltage signal. The load capacitance equivalent to the load undergoes a dynamic process, and the voltage of the power supply circuit exhibits a certain fluctuation pattern during the period when the first controllable switch is closed. In the absence of a load or a short circuit, the voltage will not exhibit a certain fluctuation pattern even if the first controllable switch is closed. However, in the absence of a short circuit, the voltage will exhibit a certain fluctuation pattern when the first controllable switch is closed.

[0116] In one example, when the first controllable switch is closed, that is, within a certain period of time when the power supply circuit and the voltage acquisition circuit form a path, the voltage signal fluctuates. The processor compares the fluctuation pattern with a preset fluctuation pattern. If the fluctuation pattern does not match the preset fluctuation pattern, it is determined that a short circuit has occurred in the power supply circuit; if the fluctuation pattern matches the preset fluctuation pattern, it is determined that no short circuit has occurred in the power supply circuit. In another example, when the first controllable switch is closed, that is, within a certain period of time when the power supply circuit and the voltage acquisition circuit form a path, the voltage signal does not fluctuate. In this case, the processor can determine that a short circuit has occurred in the power supply circuit. In the event of a short circuit in the power supply circuit, the processor can control the second controllable switch of the power supply circuit to be disconnected, and the load is not charged to protect the components in the circuit. In this way, the load detection device of the embodiment of the present invention can not only detect whether a short circuit exists, but also determine whether a load is connected, reducing the risk of component damage due to large current when the load is short-circuited.

[0117] In an embodiment of the present invention, step S43, determining the state of the power supply circuit according to the fluctuation of the voltage signal, includes:

[0118] Determine the fluctuation pattern of the voltage signal and compare the fluctuation pattern with a preset fluctuation pattern;

[0119] If the fluctuation pattern does not match the preset fluctuation pattern, determining that a short circuit occurs in the power supply circuit;

[0120] When the fluctuation pattern matches the preset fluctuation pattern, it is determined that no short circuit occurs in the power supply circuit.

[0121] Specifically, when there is no short circuit in the power supply circuit 1, the voltage acquisition circuit 2 can collect a fluctuating voltage signal during a period of time when the first controllable switch 2 is closed. In the case of a short circuit in the power supply circuit 1, the voltage signal collected by the voltage acquisition circuit 2 tends to be steady-state after the first controllable switch 2 is closed, and there will be no fluctuating voltage signal. Therefore, the processor 4 can determine the state of the power supply circuit by comparing the fluctuation pattern of the voltage signal with the preset fluctuation pattern. In an embodiment of the present invention, when the fluctuation pattern does not match the preset fluctuation pattern, for example, when the voltage signal received by the processor 4 tends to be stable, the processor 4 can determine that a short circuit has occurred in the power supply circuit 1. The processor 4 further controls the disconnection of the power supply circuit 1 to avoid a situation where the current in the power supply circuit 1 is large due to a short circuit, the circuit board is burned, and the circuit components are damaged.

[0122] In an embodiment of the present invention, when the fluctuation pattern matches a preset fluctuation pattern, for example, when the voltage signal received by the processor 4 decreases from a high point to a low point within 1S, and the fluctuation process from a high point to a low point matches the preset fluctuation pattern, the processor 4 can determine that the power supply circuit 1 is not short-circuited. In one example, when the power supply circuit 1 is not short-circuited, the fluctuation pattern of the voltage signal is that the power supply voltage at the moment the power supply circuit 1 is turned on slowly decreases to a preset voltage value within a set time t. If the voltage signal at the moment the power supply circuit 1 is turned on suddenly changes to a set value, it also does not match the preset fluctuation pattern. The processor 4 further controls the closure of the power supply circuit 1. In this way, it can ensure that the load is charged when the power supply circuit 1 is not short-circuited, thereby improving the safety of the power supply circuit 1 charging the load.

[0123] Furthermore, in an embodiment of the present invention, the load detection method further includes:

[0124] When it is determined that the power supply circuit is not short-circuited, the second controllable switch provided in the power supply circuit is controlled to be closed.

[0125] Specifically, the second controllable switch 11 of the power supply circuit 1 can be disposed between the negative pole of the power supply and the negative pole of the power connector. When the second controllable switch 11 is closed, the power supply circuit 1 is turned on, the positive pole of the power supply is electrically connected to the positive pole of the load via the connector, and the negative pole of the power supply is electrically connected to the negative pole of the load via the connector, and the power supply begins to charge the load. In embodiments of the present invention, upon determining that the power supply circuit 1 is not short-circuited, the processor 4 controls the conduction of the power supply circuit 1, thereby improving the safety of the power supply circuit 1 in charging the load.

[0126] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0127] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A load detection device, characterized in that: include: Power supply circuit, used to supply power to the load; A voltage acquisition circuit is configured to acquire a voltage signal from the power supply circuit; A first controllable switch is provided between the voltage acquisition circuit and the power supply circuit; as well as The processor is configured to: controlling the first controllable switch to close; Acquiring a voltage signal collected by the voltage collection circuit; determining a state of the power supply circuit according to fluctuations of the voltage signal; Wherein, the voltage acquisition circuit includes: a first resistor, a second resistor, and a third resistor; one end of the first resistor is electrically connected to one end of the second resistor, and the other end of the first resistor is electrically connected to the power supply circuit via the first controllable switch; the other end of the second resistor is grounded, and a node between the first resistor and the second resistor is electrically connected to the processor via the third resistor; a resistor assembly connected in parallel with the first resistor and the second resistor connected in series; the resistor assembly includes a fourth resistor and a fifth resistor connected in series; The preset fluctuation law is determined by the following formula: U=E(1-e -t / RC ); Wherein, U is the real-time voltage value of the load capacitor of the load, E is the steady-state voltage value of the load capacitor, C is the capacitance value of the load capacitor, t is the preset time, and R is the resistance value of the first resistor, the second resistor, and the resistance component after being connected in parallel; The processor is further configured to: The charging time of the load is controlled by adjusting the resistance value of the resistor component.

2. The load detection device according to claim 1, characterized in that: The processor being configured to determine the state of the power supply circuit according to the fluctuation of the voltage signal includes: the processor being configured to: determining a fluctuation pattern of the voltage signal; comparing the fluctuation pattern with a preset fluctuation pattern; In the case where the fluctuation pattern does not match the preset fluctuation pattern, determining that a short circuit occurs in the power supply circuit; In a case where the fluctuation pattern matches the preset fluctuation pattern, it is determined that no short circuit occurs in the power supply circuit.

3. The load detection device according to claim 2, characterized in that: The power supply circuit includes a second controllable switch for controlling on and off of the power supply circuit. The processor is further configured to: When it is determined that no short circuit occurs in the power supply circuit, the second controllable switch is controlled to be closed.

4. The load detection device according to claim 1, characterized in that: The processor is configured to obtain the voltage signal collected by the voltage collection circuit, including: The processor is configured to obtain a voltage signal collected by the voltage collection circuit within a preset time.

5. The load detection device according to claim 3, characterized in that: The power supply circuit also includes a power supply, a power connector and a load connector; the positive pole of the power supply is electrically connected to the positive pole of the power connector, the negative pole of the power supply is electrically connected to the negative pole of the power connector, the positive pole of the power connector is electrically connected to the positive pole of the load connector, the negative pole of the power connector is electrically connected to the negative pole of the load connector, and the second controllable switch is arranged between the negative pole of the power supply and the negative pole of the power connector.

6. An unmanned device charging system, characterized in that: include: An unmanned device, a power supply device, and a load detection device according to any one of claims 1 to 5.

7. A load detection method, characterized in that: include: Controlling the first controllable switch to close to conduct the power supply circuit and the voltage collection circuit; Acquire the voltage signal collected by the voltage collection circuit within a preset time; determining a state of the power supply circuit according to fluctuations of the voltage signal; Wherein, the power supply circuit is used to supply power to the load; The voltage acquisition circuit is configured to acquire a voltage signal from the power supply circuit; The first controllable switch is arranged between the voltage acquisition circuit and the power supply circuit; The voltage acquisition circuit includes: a first resistor, a second resistor, and a third resistor; one end of the first resistor is electrically connected to one end of the second resistor, and the other end of the first resistor is electrically connected to the power supply circuit via the first controllable switch; the other end of the second resistor is grounded, and a node between the first resistor and the second resistor is electrically connected to the processor via the third resistor; a resistor assembly connected in parallel with the first resistor and the second resistor connected in series; the resistor assembly includes a fourth resistor and a fifth resistor connected in series; The preset fluctuation law is determined by the following formula: U=E(1-e -t / RC ); Wherein, U is the real-time voltage value of the load capacitor of the load, E is the steady-state voltage value of the load capacitor, C is the capacitance value of the load capacitor, t is the preset time, and R is the resistance value of the first resistor, the second resistor, and the resistance component after being connected in parallel; The processor is further configured to: The charging time of the load is controlled by adjusting the resistance value of the resistor component.

8. The load detection method according to claim 7, characterized in that: Determining the state of the power supply circuit according to the fluctuation of the voltage signal includes: determining a fluctuation pattern of the voltage signal, and comparing the fluctuation pattern with a preset fluctuation pattern; In the case where the fluctuation pattern does not match the preset fluctuation pattern, determining that a short circuit occurs in the power supply circuit; In a case where the fluctuation pattern matches the preset fluctuation pattern, it is determined that no short circuit occurs in the power supply circuit.

9. The load detection method according to claim 8, characterized in that: Also includes: When it is determined that no short circuit occurs in the power supply circuit, a second controllable switch provided in the power supply circuit is controlled to be closed.

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