Voltage detection method of charging module, charging module and charging system

Abstract

The invention discloses a voltage detection method of a charging module, the charging module and a charging system. A DC / DC unit is controlled to be in a first preset state; performing first state detection on the anti-reverse circuit based on the sampling voltage of each voltage sampling circuit; and if a result of the first state detection fails to determine the state of the anti-reverse-flow circuit, controlling the DC / DC unit to be in a second preset state, performing second state detection on the anti-reverse-flow circuit based on the current sampling voltage of each voltage sampling circuit, and determining the state of the anti-reverse-flow circuit. The technical problem that the state of the anti-reverse-flow circuit of the charging module cannot be accurately judged in the prior art is solved, and the technical effect of accurately judging whether the anti-reverse-flow circuit has a fault and the specific fault type through voltage sampling and comparison in multiple preset states is achieved.

Description

Technical Field

[0001] The present application relates to the field of charging module detection, and particularly to a voltage detection method for a charging module, a charging module, and a charging system. Background Art

[0002] In a charging module, an anti-reverse circuit serves as an important protection circuit, and its main function is to prevent the high voltage of the subsequent load from being reverse-fed to the charging module. Once the anti-reverse circuit fails, it may cause damage to the electrolytic capacitor of the charging module and even lead to safety accidents. Therefore, timely detection of the fault state of the anti-reverse circuit is crucial for the safe operation of the charging module.

[0003] In the prior art, a single state detection is usually adopted to determine whether there is a fault in the anti-reverse circuit. For example, the voltage difference or voltage change characteristics before and after the anti-reverse circuit are detected for judgment. However, this detection method in a single state is easily affected by the working state and external environment, and cannot accurately determine the actual state of the anti-reverse circuit, posing a risk of misjudgment. When the fault state of the anti-reverse circuit is misjudged, it may cause the charging module to continue working in an unsafe state, bringing potential safety hazards. Summary of the Invention

[0004] The main purpose of the present application is to provide a voltage detection method for a charging module, a charging module, and a charging system, aiming to solve the technical problem in the prior art of the present application that the state of the anti-reverse circuit of the charging module cannot be accurately determined.

[0005] To achieve the above object, the present application provides a voltage detection method for a charging module. The charging module includes a cascaded AC / DC unit and a DC / DC unit. The DC / DC unit includes a plurality of output circuits and an anti-reverse circuit. Each output circuit is connected to a load through the anti-reverse circuit, and voltage sampling circuits are provided at both the input end and the output end of the anti-reverse circuit. The method includes: controlling the DC / DC unit to be in a first preset state; performing a first state detection on the anti-reverse circuit based on the sampling voltages of the voltage sampling circuits; if the result of the first state detection fails to determine the state of the anti-reverse circuit, controlling the DC / DC unit to be in a second preset state, and performing a second state detection on the anti-reverse circuit based on the current sampling voltages of the voltage sampling circuits and determining the state of the anti-reverse circuit.

[0006] Optionally, controlling the DC / DC unit to a first preset state includes: controlling the DC / DC unit to start and disconnect the load; the first state detection of the reverse protection circuit based on the sampling voltages of the voltage sampling circuits includes: obtaining the first sampling voltages of the voltage sampling circuits and performing the first state detection of the reverse protection circuit based on the first sampling voltages; controlling the DC / DC unit to a second preset state includes: controlling the DC / DC unit to turn off and obtaining the second sampling voltages of the voltage sampling circuits; the second state detection of the reverse protection circuit based on the current sampling voltages of the voltage sampling circuits and determining the state of the reverse protection circuit includes: determining the voltage drop rates of the voltage sampling circuits based on the first sampling voltages and the second sampling voltages; performing the second state detection of the reverse protection circuit based on the voltage drop rates of the voltage sampling circuits and determining the state of the reverse protection circuit.

[0007] Optionally, a plurality of the voltage sampling circuits include a front-end voltage sampling circuit located on the input side of the reverse protection circuit and a rear-end voltage sampling circuit located on the output side of the reverse protection circuit; obtaining the first sampling voltages of the voltage sampling circuits includes: respectively obtaining the first front-end sampling voltage of the front-end voltage sampling circuit and the first rear-end sampling voltage of the rear-end voltage sampling circuit; the first state detection of the reverse protection circuit based on the first sampling voltages includes: if the first front-end sampling voltage is the same as the first rear-end sampling voltage, determining that the reverse protection circuit is in a good state or a short-circuit state; if the first front-end sampling voltage is different from the first rear-end sampling voltage, determining that the reverse protection circuit is in an open-circuit state.

[0008] Optionally, determining the voltage drop rates of the voltage sampling circuits based on the first sampling voltages and the second sampling voltages includes: determining the voltage drop rate of the sampling voltage of the front-end voltage sampling circuit and the voltage drop rate of the sampling voltage of the rear-end voltage sampling circuit based on the first sampling voltages and the second sampling voltages; the second state detection of the reverse protection circuit based on the voltage drop rates of the voltage sampling circuits and determining the state of the reverse protection circuit includes: comparing whether the voltage drop rate of the sampling voltage of the front-end voltage sampling circuit is the same as the voltage drop rate of the sampling voltage of the rear-end voltage sampling circuit; if the voltage drop rate of the sampling voltage of the front-end voltage sampling circuit is the same as the voltage drop rate of the sampling voltage of the rear-end voltage sampling circuit, determining that the reverse protection circuit is in a short-circuit state; if the voltage drop rate of the sampling voltage of the front-end voltage sampling circuit is different from the voltage drop rate of the sampling voltage of the rear-end voltage sampling circuit, determining that the reverse protection circuit is in a good state.

[0009] Optionally, controlling the DC / DC unit to a first preset state includes: controlling the AC / DC unit to start and controlling the DC / DC unit to turn off and connect to the load; the first state detection of the reverse protection circuit based on the sampled voltages of each voltage sampling circuit includes: obtaining the first sampled voltages of each voltage sampling circuit and performing the first state detection of the reverse protection circuit based on the first sampled voltages; controlling the DC / DC unit to a second preset state includes: disconnecting the load and controlling the DC / DC unit to start, and obtaining the second sampled voltages of each voltage sampling circuit; the second state detection of the reverse protection circuit based on the current sampled voltages of each voltage sampling circuit and determining the state of the reverse protection circuit includes: performing the second state detection of the reverse protection circuit based on the second sampled voltages and determining the state of the reverse protection circuit.

[0010] Optionally, the charging module further includes a relay combination circuit, and the relay combination circuit is connected between the output circuit and the reverse protection circuit; before obtaining the first sampled voltages of each voltage sampling circuit and performing the first state detection of the reverse protection circuit based on the first sampled voltages, the method further includes: controlling the relay combination circuit to be in an open state so that the output circuit and the subsequent circuit are in an open circuit state, and connecting to the load; obtaining the load voltage across the load; comparing the load voltage with the maximum output voltage of the output circuit; if the load voltage is greater than the maximum output voltage, disconnecting the load; if the load voltage is less than or equal to the maximum output voltage, controlling each output circuit to be connected in series through the relay combination circuit.

[0011] Optionally, obtaining the first sampled voltages of each voltage sampling circuit includes: respectively obtaining the first front-end sampled voltage of the front-end voltage sampling circuit and the first back-end sampled voltage of the back-end voltage sampling circuit; the first state detection of the reverse protection circuit based on the first sampled voltages includes: if the first front-end sampled voltage is the same as the first back-end sampled voltage, determining that the reverse protection circuit is in a short-circuit state; if the first front-end sampled voltage is different from the first back-end sampled voltage, determining that the reverse protection circuit is in an open-circuit state or a good state.

[0012] Optionally, the obtaining of the second sampling voltages of the voltage sampling circuits includes: respectively obtaining the second front-end sampling voltage of the front-end voltage sampling circuit and the second back-end sampling voltage of the back-end voltage sampling circuit; the performing of a second state detection on the reverse connection prevention circuit based on the second sampling voltages and determining the state of the reverse connection prevention circuit includes: if the second front-end sampling voltage is the same as the second back-end sampling voltage, determining that the reverse connection prevention circuit is in a good state; if the second front-end sampling voltage is different from the second back-end sampling voltage, determining that the reverse connection prevention circuit is in an open circuit state.

[0013] In addition, to achieve the above object, the present application also provides a charging module including a controller. The controller is configured to execute the voltage detection method of the charging module to perform fault detection on the reverse connection prevention circuit in the charging module.

[0014] In addition, the present application also provides a charging system including at least two charging modules, at least one charging interface, a control center, and a power distribution device; the power distribution device is respectively connected to the control center, each of the charging modules, and each of the charging interfaces. Among them, each of the charging modules is configured to convert the alternating current of the power grid into direct current and provide it to each of the charging interfaces; the control center is configured to obtain the required power of each charging interface, and generate a scheduling instruction according to the connection relationship of the controllable switches in the power distribution device and each required power; the power distribution device is configured to control the opening or closing of the controllable switches according to the scheduling instruction to distribute the output power of each charging module to each charging interface.

[0015] The beneficial effects that the present application can achieve are as follows:

[0016] By providing voltage sampling circuits at the input end and the output end of the reverse connection prevention circuit and performing multiple state detections under different preset states, an accurate judgment of the state of the reverse connection prevention circuit is realized.

[0017] First, control the DC / DC unit to enter the first preset state, obtain the sampling voltages of the voltage sampling circuits, and perform the first state detection. If the state of the reverse connection prevention circuit cannot be determined by the result of the first detection, switch the DC / DC unit to the second preset state and perform the second state detection, so as to finally determine the state of the reverse connection prevention circuit. Through multiple detections under different preset states, the misjudgment that may be caused by a single state detection is avoided.

[0018] During the detection process, by comparing the voltage characteristics before and after the reverse connection prevention circuit in multiple preset states, it is possible to accurately distinguish whether the reverse connection prevention circuit is in a good state, a short circuit state, or an open circuit state. Once a fault in the reverse connection prevention circuit is detected, the faulty module is promptly removed from the charging system, effectively preventing the damage of the charging module that may be caused by the failure of the reverse connection prevention circuit.

[0019] In addition, before detecting the anti-reverse circuit, the output circuit is pre-controlled through a relay combination circuit, and the load voltage is judged, so as to provide an additional safety protection measure during the detection process.

[0020] Through the above technical solution, the technical problem in the prior art that the fault state of the anti-reverse circuit of the charging module cannot be accurately judged is solved, the accurate judgment of the state of the anti-reverse circuit is realized, and the safety and reliability of the charging system are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The first circuit schematic diagram of the charging module provided by the present invention;

[0022] Figure 2 The second circuit schematic diagram of the charging module provided by the present invention;

[0023] Figure 3 The flow schematic diagram of the anti-reverse diode detection method of the charging module provided by the present invention;

[0024] Figure 4 The first anti-reverse diode detection flow chart provided by the present invention;

[0025] Figure 5 The second anti-reverse diode detection flow chart provided by the present invention;

[0026] Figure 6 The third anti-reverse diode detection flow chart provided by the present invention;

[0027] Figure 7 The structure schematic diagram of the charging system provided by the present invention;

[0028] Figure 8 The single-module connection load schematic diagram provided by the present invention;

[0029] Figure 9 The whole-pile multi-module connection load schematic diagram provided by the present invention.

[0030] The realization of the purpose of this application, functional features and advantages will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0032] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship, movement conditions, etc. between components in a certain preset posture (as shown in the attached drawings). If the preset posture changes, the directional indications will also change accordingly.

[0033] In the present invention, unless otherwise clearly defined and limited, terms such as "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the communication inside two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] 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 should not be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel scenarios. Taking "A and / or B" as an example, it includes scenario A, scenario B, or the scenario where both A and B are satisfied simultaneously. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement them. When the combination of technical solutions conflicts with each other or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0035] First, the circuit structure of the charging module involved in the present application will be introduced below.

[0036] Figure 1 is a schematic diagram of the circuit structure of the charging module provided in an embodiment of the present application. Refer to Figure 1, the charging module includes an AC / DC unit and a DC / DC unit, and the DC / DC unit includes a rectifier circuit, an electrolytic capacitor, a voltage sampling circuit, an anti-reverse circuit, an output Y capacitor and an X capacitor network, and an output dummy load. The DC / DC unit has two output circuits, namely a lower output circuit and an upper output circuit. The upper output circuit is composed of a main transformer 1, a rectifier circuit (composed of diodes D1, D2, D3 and D4) and an electrolytic capacitor C2, and the lower output circuit is composed of a main transformer 2, a rectifier circuit (composed of diodes D5, D6, D7 and D8) and an electrolytic capacitor C1. The two output circuits are connected to the load through an anti-reverse circuit. In the charging module, the anti-reverse circuit includes an anti-reverse diode D10, and the anti-reverse diode D10 is used to prevent the voltage of the battery load from being reversed to protect the lower output circuit and the upper output circuit. The voltage sampling circuit is arranged at the input and output ends of the anti-reverse circuit to detect the state of the anti-reverse circuit. The voltage sampling circuit includes a voltage sampling circuit 1, a voltage sampling circuit 2 and a voltage sampling circuit 3. The voltage sampling circuit 1 and the voltage sampling circuit 2 are arranged at the input end of the anti-reverse circuit to collect the input end voltage of the anti-reverse diode D10; the voltage sampling circuit 3 is arranged at the output end of the anti-reverse circuit to collect the output end voltage of the anti-reverse diode D10.

[0037] Figure 2 A schematic diagram of the circuit structure of a charging module provided in another embodiment of the present application, referring to Figure 2 The charging module includes an AC / DC unit and a DC / DC unit. The DC / DC unit includes a rectifier circuit, an electrolytic capacitor, a voltage sampling circuit, an anti-reverse circuit, an output Y capacitor and an X capacitor network, and an output dummy load. Figure 1 The charging module shown is different in the anti-reverse circuit. The anti-reverse circuit in the charging module includes an anti-reverse diode D9 and an anti-reverse diode D10. The anti-reverse diode D9 is used to prevent the voltage of the battery load from being reversed to protect the lower output circuit; the anti-reverse diode D10 is used to prevent the voltage of the battery load from being reversed to protect the upper output circuit. The voltage sampling circuit includes a voltage sampling circuit 1, a voltage sampling circuit 2 and a voltage sampling circuit 3. The voltage sampling circuit 1 is set at the input end of the anti-reverse diode D9 to collect the input end voltage of the anti-reverse diode D9; the voltage sampling circuit 2 is set at the input end of the anti-reverse diode D10 to collect the input end voltage of the anti-reverse diode D10; the voltage sampling circuit 3 is set at the output end of the anti-reverse circuit to collect the output end voltages of the anti-reverse diode D9 and the anti-reverse diode D10.

[0038] The charging control method provided by this application is introduced below. Figure 3 This is a flow chart of a voltage detection method for a charging module provided in an embodiment of the present application, such as Figure 3 As shown, the method may include the following steps:

[0039] S1: Control the DC / DC unit to be in the first preset state;

[0040] S2: Based on the sampling voltages of each voltage sampling circuit, perform a first state detection on the reverse protection circuit;

[0041] S3: If the result of the first state detection fails to determine the state of the reverse protection circuit, control the DC / DC unit to be in the second preset state, and based on the current sampling voltages of each voltage sampling circuit, perform a second state detection on the reverse protection circuit and determine the state of the reverse protection circuit.

[0042] Specifically, first, control the DC / DC unit to enter the first preset state to set a specific working state and create conditions for the state detection of the reverse protection circuit. Then, in the first preset state, collect voltages through each voltage sampling circuit to obtain the sampling voltages of each voltage sampling circuit. Subsequently, based on the sampling voltages of each voltage sampling circuit, perform a first state detection on the reverse protection circuit. By collecting and analyzing the voltage values before and after the reverse protection circuit, preliminarily judge the working state of the reverse protection circuit. If the result of the first state detection fails to determine the state of the reverse protection circuit, switch the DC / DC unit to the second preset state, collect voltages through each voltage sampling circuit again to obtain the current sampling voltages of each voltage sampling circuit. After that, perform a second state detection on the reverse protection circuit based on the current sampling voltages of each voltage sampling circuit, so as to determine the state of the reverse protection circuit.

[0043] By collecting the voltages at the input and output ends of the reverse protection circuit under two different states and comprehensively analyzing the collected voltage values, it is possible to accurately judge whether the reverse protection circuit is faulty and determine the fault state of the reverse protection circuit, improving the accuracy and reliability of the state judgment of the reverse protection circuit.

[0044] As an optional implementation manner, the control of the DC / DC unit to be in the first preset state includes:

[0045] S11: Control the DC / DC unit to start and disconnect the load;

[0046] The first state detection of the reverse protection circuit based on the sampling voltages of each voltage sampling circuit includes:

[0047] S21: Obtain the first sampling voltages of each voltage sampling circuit, and based on the first sampling voltages, perform a first state detection on the reverse protection circuit;

[0048] The control of the DC / DC unit to be in the second preset state includes:

[0049] S31: Control the DC / DC unit to be turned off, and obtain the second sampling voltage of each voltage sampling circuit;

[0050] S32: performing a second state detection on the anti-reverse circuit based on the current sampling voltage of each voltage sampling circuit and determining the state of the anti-reverse circuit, including:

[0051] S33: determining a voltage drop speed of each of the voltage sampling circuits based on the first sampling voltage and the second sampling voltage;

[0052] S34: performing a second state detection on the anti-reverse circuit based on the voltage drop speed of each of the voltage sampling circuits and determining the state of the anti-reverse circuit.

[0053] Specifically, first, the DC / DC unit is set to the first preset state, that is, the DC / DC unit is controlled to start and disconnect the load. By controlling the load contactor to disconnect, the charging module is isolated from the external load. In this state, the DC / DC unit is in a startup state, but no load is connected, and a stable initial voltage value of the anti-reverse circuit can be obtained. Then, in the first preset state, the voltage values ​​at the corresponding positions are respectively collected by each voltage sampling circuit to obtain a first sampled voltage. Then, based on the collected first sampled voltage, the anti-reverse circuit is subjected to a first state detection, and the working state of the anti-reverse circuit is preliminarily judged by analyzing the voltage values ​​at the input and output ends of the anti-reverse circuit.

[0054] When a second state detection is required, the DC / DC unit is switched to the second preset state, that is, the DC / DC unit is controlled to be turned off. After the DC / DC unit is turned off, the voltage at each sampling point will gradually decrease. When the anti-reverse circuit is intact, the voltage drop rate at each measurement point is different. The voltage drop rate at the input end of the anti-reverse circuit is mainly determined by the capacity of the electrolytic capacitor in the output circuit and its corresponding discharge circuit; the voltage drop rate at the output end of the anti-reverse circuit is jointly determined by the output Y capacitor and X capacitor network and the output dummy load. Subsequently, the voltage value is collected again through each voltage sampling circuit to obtain a second sampling voltage. After obtaining the second sampling voltage, the voltage drop rate of each voltage sampling point is calculated based on the first sampling voltage and the second sampling voltage. Another way is that after the DC / DC unit is turned off, two time points are selected to perform voltage detection through each voltage sampling circuit, and the voltage difference of each voltage sampling circuit at the two time points is calculated to determine the voltage drop rate. After that, the anti-reverse circuit is subjected to a second state detection by analyzing the voltage drop rate corresponding to each voltage sampling circuit. By comparing the voltage drop speeds at the input and output ends of the anti-reverse circuit, it is further confirmed whether the anti-reverse circuit is faulty and the specific fault status.

[0055] Through this detection method based on dynamic characteristics, compared with simply comparing voltage values, it is possible to more accurately determine whether there is a fault in the reverse protection circuit. Among them, by combining the detection processes in two different preset states, both the static voltage characteristics and the dynamic change characteristics are considered, thereby improving the accuracy of judging the state of the reverse protection circuit.

[0056] As an alternative implementation, the multiple voltage sampling circuits include a front-end voltage sampling circuit located on the input side of the reverse protection circuit and a rear-end voltage sampling circuit located on the output side of the reverse protection circuit;

[0057] The obtaining of the first sampling voltage of each voltage sampling circuit includes:

[0058] S211: respectively obtain the first front-end sampling voltage of the front-end voltage sampling circuit and the first rear-end sampling voltage of the rear-end voltage sampling circuit;

[0059] The first state detection of the reverse protection circuit based on the first sampling voltage includes:

[0060] S212: if the first front-end sampling voltage is the same as the first rear-end sampling voltage, determine that the reverse protection circuit is in a good state or a short-circuit state;

[0061] S213: if the first front-end sampling voltage is different from the first rear-end sampling voltage, determine that the reverse protection circuit is in an open-circuit state.

[0062] Specifically, the voltage sampling circuit includes a front-end voltage sampling circuit and a rear-end voltage sampling circuit. Specifically, the front-end voltage sampling circuit is arranged on the input side of the reverse protection circuit, and the rear-end voltage sampling circuit is arranged on the output side of the reverse protection circuit.

[0063] When performing the first state detection, first, voltage values are respectively collected by the front-end voltage sampling circuit and the rear-end voltage sampling circuit to obtain the first front-end sampling voltage and the first rear-end sampling voltage. Refer to Figure 1 and Figure 2 As shown, the front-end voltage sampling circuit includes voltage sampling circuit 1 and voltage sampling circuit 2, which are used to collect the voltage at the input end of the reverse protection circuit; the rear-end voltage sampling circuit, namely voltage sampling circuit 3, is used to collect the voltage at the output end of the reverse protection circuit.

[0064] After obtaining the sampled voltage, the state of the reverse protection circuit is judged by comparing the first front-end sampled voltage with the first back-end sampled voltage. In the normal working or short-circuit state, the voltages at the front and back ends of the reverse protection circuit should be the same, while the open-circuit state will cause a difference in the voltages at the front and back ends. Therefore, if the first front-end sampled voltage is the same as the first back-end sampled voltage, it indicates that the reverse protection circuit is in good condition or short-circuited; if the first front-end sampled voltage is different from the first back-end sampled voltage, it means that the reverse protection circuit is in an open-circuit state.

[0065] Refer to Figure 1 , the voltage sampling circuit 1 is used to obtain the voltage Vout1 of the lower output circuit, and the voltage sampling circuit 2 is used to obtain the voltage Vout2 of the upper output circuit; the voltage sampling circuit 3 is used to obtain the output voltage Vout3 of the reverse protection diode D10. When the two output circuits are operating in parallel, the voltages collected by the voltage sampling circuit 1 and the voltage sampling circuit 2 can both be used as the input voltage of the reverse protection diode D10. As Figure 4 shown, for the circuit structure of the charging module as Figure 1 shown, when detecting the reverse protection circuit in the charging module, first, the DC / DC unit is started and the load is disconnected, and it is set to the first preset state. Then, in the first preset state, voltage sampling is performed through the front-end voltage sampling circuit (voltage sampling circuit 1, voltage sampling circuit 2) and the back-end voltage sampling circuit (voltage sampling circuit 3) to obtain the first front-end sampled voltage (Vout1 or Vout2) and the first back-end sampled voltage (Vout3). Then, the first front-end sampled voltage (Vout1 or Vout2) and the first back-end sampled voltage (Vout3) are compared to judge whether the voltages at the front and back of the reverse protection circuit are the same. If the first front-end sampled voltage (Vout1 or Vout2) is the same as the first back-end sampled voltage (Vout3), it is determined that the reverse protection circuit (reverse protection diode D10) is in good condition or short-circuited; if the first front-end sampled voltage (Vout1 or Vout2) is different from the first back-end sampled voltage (Vout3), it is determined that the reverse protection circuit (reverse protection diode D10) is in an open-circuit state.

[0066] Refer to Figure 2 , the voltage sampling circuit 1 is used to obtain the input voltage of the reverse protection diode D9; the voltage sampling circuit 2 is used to obtain the input voltage of the reverse protection diode D10; the voltage sampling circuit 3 is used to obtain the output voltages of the reverse protection diode D9 and the reverse protection diode D10. As Figure 4 shown, for the Figure 2For the circuit structure of the charging module shown, when detecting the reverse connection prevention circuit in the charging module, first, the DC / DC unit is started and the load is disconnected, and it is set to the first preset state. Then, in the first preset state, voltage sampling is performed through the front-end voltage sampling circuit (voltage sampling circuit 1, voltage sampling circuit 2) and the back-end voltage sampling circuit (voltage sampling circuit 3) to obtain the first front-end sampling voltage (Vout1 and Vout2) and the first back-end sampling voltage (Vout3). Then, the first front-end sampling voltage (Vout1 and Vout2) and the first back-end sampling voltage (Vout3) are compared to determine whether the voltages before and after the reverse connection prevention circuit are the same. If Vout1 in the first front-end sampling voltage is the same as the first back-end sampling voltage Vout3, it is determined that the reverse connection prevention diode D9 is in a good state or a short-circuit state; if Vout1 in the first front-end sampling voltage is different from the first back-end sampling voltage Vout3, it is determined that the reverse connection prevention diode D9 is in an open-circuit state. If Vout2 in the first front-end sampling voltage is the same as the first back-end sampling voltage Vout3, it is determined that the reverse connection prevention diode D10 is in a good state or a short-circuit state; if Vout2 in the first front-end sampling voltage is different from the first back-end sampling voltage Vout3, it is determined that the reverse connection prevention diode D10 is in an open-circuit state.

[0067] As an alternative implementation, the determining the voltage drop speed of each of the voltage sampling circuits based on the first sampling voltage and the second sampling voltage includes:

[0068] S331: Determine the sampling voltage drop speed of the front-end voltage sampling circuit and the sampling voltage drop speed of the back-end voltage sampling circuit based on the first sampling voltage and the second sampling voltage;

[0069] The second state detection of the reverse connection prevention circuit based on the voltage drop speed of each of the voltage sampling circuits and determining the state of the reverse connection prevention circuit includes:

[0070] S341: Compare whether the sampling voltage drop speed of the front-end voltage sampling circuit is the same as the sampling voltage drop speed of the back-end voltage sampling circuit;

[0071] S342: If the sampling voltage drop speed of the front-end voltage sampling circuit is the same as the sampling voltage drop speed of the back-end voltage sampling circuit, determine that the reverse connection prevention circuit is in a short-circuit state;

[0072] S343: If the sampling voltage drop speed of the front-end voltage sampling circuit is different from the sampling voltage drop speed of the back-end voltage sampling circuit, determine that the reverse connection prevention circuit is in a good state.

[0073] Specifically, when the first state detection of the reverse connection prevention circuit is performed based on the sampling voltages of each voltage sampling circuit and the specific state of the reverse connection prevention circuit cannot be determined, such as only determining that the reverse connection prevention circuit is in a good state or a short - circuit state, a second state detection of the reverse connection prevention circuit is performed. At this time, the DC / DC unit is controlled to be in the second preset state, that is, the DC / DC unit is turned off, and then voltage acquisition is performed through each voltage sampling circuit to obtain the second sampling voltage. Subsequently, the voltage drop rate of the sampling voltage of the front - end voltage sampling circuit and the voltage drop rate of the sampling voltage of the back - end voltage sampling circuit are determined by the first sampling voltage and the second sampling voltage. Subsequently, it is compared whether the voltage drop rate of the sampling voltage of the front - end voltage sampling circuit is the same as the voltage drop rate of the sampling voltage of the back - end voltage sampling circuit. If the voltage drop rate of the sampling voltage of the front - end voltage sampling circuit is the same as the voltage drop rate of the sampling voltage of the back - end voltage sampling circuit, it is determined that the reverse connection prevention circuit is in a short - circuit state. If the voltage drop rate of the sampling voltage of the front - end voltage sampling circuit is different from the voltage drop rate of the sampling voltage of the back - end voltage sampling circuit, it is determined that the reverse connection prevention circuit is in a good state.

[0074] For example Figure 1For the circuit structure of the charging module shown, when it is determined through the first detection that the reverse protection diode D10 is in a short - circuit state or in a normal state, the DC / DC unit is turned off. In this state, the voltage - drop rates are collected by the voltage - sampling circuit 1, the voltage - sampling circuit 2, and the voltage - sampling circuit 3. The voltage - drop rates of the voltage - sampling circuit 1 and the voltage - sampling circuit 2 are the sampling voltage - drop rates of the front - end voltage - sampling circuit, that is, the drop rates of Vout1 and Vout2, and the voltage - drop rate of the voltage - sampling circuit 3 is the sampling voltage - drop rate of the back - end voltage - sampling circuit, that is, the drop rate of Vout3. Among them, the drop rate of Vout1 is determined by the capacitance of the electrolytic capacitor C1 in the lower output circuit and its corresponding discharge circuit; the drop rate of Vout2 is mainly determined by the capacitance of the electrolytic capacitor C2 in the upper output circuit and its corresponding discharge circuit; the drop rate of Vout3 is jointly determined by the overall capacitance of the output Y - capacitor and X - capacitor network (i.e., the capacitor network composed of CY1, CY2, and CX1) and the output dummy load R1. Due to the blocking characteristic of the reverse protection diode, when the reverse protection diode D10 is normal, the voltage - drop rates of each voltage - sampling circuit are different. However, when the reverse protection diode D10 is short - circuited, the voltage - drop rates of the corresponding circuits will tend to be the same. Specifically, if the reverse protection diode D10 fails due to a short - circuit, the sampling voltage - drop rate of the front - end voltage - sampling circuit (the drop rate of Vout1 or Vout2) will be the same as the sampling voltage - drop rate of the back - end voltage - sampling circuit (the drop rate of Vout3); if the reverse protection diode D10 is normal, due to the blocking of the reverse protection diode D10, the sampling voltage - drop rate of the front - end voltage - sampling circuit (the drop rate of Vout1 or Vout2) will be different from the sampling voltage - drop rate of the back - end voltage - sampling circuit (the drop rate of Vout3). Based on this principle, the sampling voltage - drop rate of the front - end voltage - sampling circuit (the drop rate of Vout1 or Vout2) is compared with the sampling voltage - drop rate of the back - end voltage - sampling circuit (the drop rate of Vout3). If the drop rates are the same, it is determined that the reverse protection diode D10 is in a short - circuit state; if the drop rates are different, it is determined that the reverse protection diode D10 is in a normal state.

[0075] For example Figure 2The circuit structure of the charging module shown. For the reverse protection diode D9, when it is determined through the first detection that the reverse protection diode D9 is in a short - circuit state or a good state, the DC / DC unit is turned off. In this state, the voltage drop rates are collected through the voltage sampling circuit 1 and the voltage sampling circuit 3. The voltage drop rate of the voltage sampling circuit 1 is the sampling voltage drop rate of the front - end voltage sampling circuit, that is, the drop rate of Vout1; the voltage drop rate of the voltage sampling circuit 3 is the sampling voltage drop rate of the back - end voltage sampling circuit, that is, the drop rate of Vout3. Due to the blocking characteristic of the reverse protection diode, in the case where the reverse protection diode D9 is good, the sampling voltage drop rate of the front - end voltage sampling circuit (the drop rate of Vout1) is different from the sampling voltage drop rate of the back - end voltage sampling circuit (the drop rate of Vout3); however, when the reverse protection diode D9 is short - circuited, the sampling voltage drop rate of the front - end voltage sampling circuit (the drop rate of Vout1) and the sampling voltage drop rate of the back - end voltage sampling circuit (the drop rate of Vout3) will tend to be the same. Based on this principle, by comparing the sampling voltage drop rate of the front - end voltage sampling circuit (the drop rate of Vout1) and the sampling voltage drop rate of the back - end voltage sampling circuit (the drop rate of Vout3), if the drop rates are the same, it is determined that the reverse protection diode D9 is in a short - circuit state; if the drop rates are different, it is determined that the reverse protection diode D9 is in a good state.

[0076] For the reverse protection diode D10, when it is determined through the first detection that the reverse protection diode D10 is in a short - circuit state or a good state, the DC / DC unit is turned off. In this state, the voltage drop rates are collected through the voltage sampling circuit 2 and the voltage sampling circuit 3. The voltage drop rate of the voltage sampling circuit 2 is the sampling voltage drop rate of the front - end voltage sampling circuit, that is, the drop rate of Vout2; the voltage drop rate of the voltage sampling circuit 3 is the sampling voltage drop rate of the back - end voltage sampling circuit, that is, the drop rate of Vout3. Due to the blocking characteristic of the reverse protection diode, in the case where the reverse protection diode D10 is good, the sampling voltage drop rate of the front - end voltage sampling circuit (the drop rate of Vout2) is different from the sampling voltage drop rate of the back - end voltage sampling circuit (the drop rate of Vout3); however, when the reverse protection diode D10 is short - circuited, the sampling voltage drop rate of the front - end voltage sampling circuit (the drop rate of Vout2) and the sampling voltage drop rate of the back - end voltage sampling circuit (the drop rate of Vout3) will tend to be the same. Based on this principle, by comparing the sampling voltage drop rate of the front - end voltage sampling circuit (the drop rate of Vout2) and the sampling voltage drop rate of the back - end voltage sampling circuit (the drop rate of Vout3), if the drop rates are the same, it is determined that the reverse protection diode D10 is in a short - circuit state; if the drop rates are different, it is determined that the reverse protection diode D10 is in a good state.

[0077] As an alternative implementation, controlling the DC / DC unit to a first preset state includes:

[0078] S11: Controlling the AC / DC unit to start and controlling the DC / DC unit to turn off and connect to the load;

[0079] The first state detection of the reverse protection circuit based on the sampling voltages of each voltage sampling circuit includes:

[0080] S21: Obtaining the first sampling voltage of each voltage sampling circuit and performing the first state detection on the reverse protection circuit based on the first sampling voltage;

[0081] Controlling the DC / DC unit to a second preset state includes:

[0082] S31: Disconnecting the load and controlling the DC / DC unit to start, and obtaining the second sampling voltage of each voltage sampling circuit;

[0083] The second state detection of the reverse protection circuit based on the current sampling voltages of each voltage sampling circuit and determining the state of the reverse protection circuit includes:

[0084] S32: Performing the second state detection on the reverse protection circuit based on the second sampling voltage and determining the state of the reverse protection circuit.

[0085] Specifically, controlling the DC / DC unit to the first preset state is: controlling the AC / DC unit to start and controlling the DC / DC unit to turn off and connect to the load. Subsequently, in the first preset state, the first state detection is performed on the reverse protection circuit based on the sampling voltages of each voltage sampling circuit. Specifically, first, the corresponding voltage values are obtained through each voltage sampling circuit in the charging module to obtain the first sampling voltage. For example, for the Figure 2 charging module, each voltage sampling circuit includes voltage sampling circuit 1, voltage sampling circuit 2, and voltage sampling circuit 3, and the sampled voltages Vout1, Vout2, and Vout3 collected respectively are the first sampling voltages. Subsequently, the reverse protection circuit is detected according to the first sampling voltage. If the result of the first state detection cannot determine the state of the reverse protection circuit, the DC / DC unit is controlled to the second preset state, that is, disconnecting the load and controlling the DC / DC unit to start. Then, the second sampling voltage of each voltage sampling circuit is obtained. In Figure 2Among them, voltage acquisition is performed again through voltage sampling circuit 1, voltage sampling circuit 2, and voltage sampling circuit 3 to obtain new sampling voltages Vout1, Vout2, and Vout3, which are the current sampling voltages of each voltage sampling circuit. After that, based on the current sampling voltages of each voltage sampling circuit, a second state detection of the reverse connection prevention circuit is performed to determine the state of the reverse connection prevention circuit, that is, a second state detection of the reverse connection prevention circuit is performed through the second sampling voltage to determine the state of the reverse connection prevention circuit.

[0086] Through Figure 2 The charging module in is specifically described. When the output voltage of the charging module is in the range of 50V to 500V, this solution can be used for detection. As Figure 6 shown, first, control the AC / DC unit of the charging module to start and control the DC / DC unit to turn off and connect the load. In this state, a first state detection of the reverse connection prevention circuit is performed based on the sampling voltages of each voltage sampling circuit. Specifically, the input voltage of the reverse connection prevention diode D9 of the lower output circuit is collected through voltage sampling circuit 1 to obtain the sampling voltage Vout1; the input voltage of the reverse connection prevention diode D10 of the upper output circuit is collected through voltage sampling circuit 2 to obtain the sampling voltage Vout2; the common output voltage of the reverse connection prevention diodes is collected through voltage sampling circuit 3 to obtain the sampling voltage Vout3. The obtained sampling voltages Vout1, Vout2, and Vout3 are the first sampling voltages. Then, a first state detection of the reverse connection prevention circuit is performed according to the obtained first sampling voltages. If the specific state of the reverse connection prevention circuit cannot be determined in the first state detection, disconnect the load and control the DC / DC unit to start, and obtain the second sampling voltages of each voltage sampling circuit. Specifically, the input voltage of the reverse connection prevention diode D9 of the lower output circuit is collected again through voltage sampling circuit 1 to obtain the sampling voltage Vout1; the input voltage of the reverse connection prevention diode D10 of the upper output circuit is collected through voltage sampling circuit 2 to obtain the sampling voltage Vout2; the common output voltage of the reverse connection prevention diodes is collected through voltage sampling circuit 3 to obtain the sampling voltage Vout3. The sampling voltages Vout1, Vout2, and Vout3 obtained this time are the second sampling voltages. After that, a second state detection of the reverse connection prevention circuit is performed according to the second sampling voltages to determine the state of the reverse connection prevention circuit.

[0087] As an optional implementation manner, the charging module further includes a relay combination circuit, and the relay combination circuit is connected between the output circuit and the reverse connection prevention circuit;

[0088] Before obtaining the first sampling voltages of each of the voltage sampling circuits and performing a first state detection of the reverse connection prevention circuit based on the first sampling voltages, the method further includes:

[0089] S22: Control the relay combination circuit to be in the off state so that the output circuit and the subsequent circuit are in an open circuit state, and connect a load.

[0090] S23: Obtain the load voltage across the load.

[0091] S24: Compare the load voltage with the maximum output voltage of the output circuit.

[0092] S25: If the load voltage is greater than the maximum output voltage, disconnect the load.

[0093] S26: If the load voltage is less than or equal to the maximum output voltage, control each of the output circuits to be connected in series through the relay combination circuit.

[0094] Specifically, the charging module further includes a relay combination circuit. Before obtaining the first sampling voltage of each voltage sampling circuit and performing the first state detection on the reverse protection circuit based on the first sampling voltage, first, control the relay combination circuit to be in the off state, so that the output circuit in the charging module and the subsequent circuit are in an open circuit state, and connect a load. Subsequently, obtain the load voltage across the connected load. Then, compare the load voltage with the maximum output voltage of the output circuit. If the load voltage is greater than the maximum output voltage, disconnect the load; if the load voltage is less than or equal to the maximum output voltage, control each output circuit to be connected in series through the relay combination circuit.

[0095] For Figure 1 The circuit structure of the charging module shown also includes a relay combination network, which includes a first relay RLY1, a second relay RLY3, and a third relay RLY2. Among them, the first relay RLY1 is connected between the negative output terminal of the lower output circuit and the negative output terminal of the upper output circuit, the second relay RLY3 is connected between the positive output terminal of the lower output circuit and the positive output terminal of the upper output circuit, and the third relay RLY2 is connected between the positive output terminal of the lower output circuit and the negative output terminal of the upper output circuit.

[0096] Before detecting the reverse protection circuit (i.e., the reverse protection diode D10) in the charging module under the condition of having a load, judge the load voltage to ensure safety during detection. As Figure 5As shown, first, control the AC / DC unit to start and control the DC / DC unit to turn off. Then, set the relay combination network to logic state one. Specifically, control the first relay RLY1, the second relay RLY2, and the third relay RLY3 to all be open. At this time, the two output circuits are completely isolated from the external load. Subsequently, connect the load by closing the load contactor. Assume that the maximum output voltage of these two output circuits is 1000V. Then, obtain the load voltage across the load, that is, the load battery voltage Uo3. Next, compare the load battery voltage Uo3 with the maximum output voltage of the output circuit. If the load voltage is greater than the maximum output voltage, that is, if Uo3 is greater than 1000V, then disconnect the load by opening the load contactor. Otherwise, set the relay combination network to logic state two. Specifically, control the first relay RLY1 and the third relay RLY3 to be open, and control the second relay RLY2 to be closed, so that the lower output circuit and the upper output circuit are in series. After that, detect the anti-reverse circuit in the charging module.

[0097] Through the above preprocessing mechanism, it can ensure that the charging module detects the state of the anti-reverse circuit under safe working conditions, effectively avoiding the damage that may be caused by too high load voltage.

[0098] As an alternative implementation, the obtaining of the first sampling voltage of each of the voltage sampling circuits includes:

[0099] S211: Obtain the first front-end sampling voltage of the front-end voltage sampling circuit and the first back-end sampling voltage of the back-end voltage sampling circuit respectively;

[0100] The performing of the first state detection on the anti-reverse circuit based on the first sampling voltage includes:

[0101] S212: If the first front-end sampling voltage is the same as the first back-end sampling voltage, determine that the anti-reverse circuit is in a short-circuit state;

[0102] S213: If the first front-end sampling voltage is different from the first back-end sampling voltage, determine that the anti-reverse circuit is in an open-circuit state or a good state.

[0103] Specifically, the obtaining of the first sampling voltage of each voltage sampling circuit is specifically to obtain the first front-end sampling voltage of the front-end voltage sampling circuit and the first back-end sampling voltage of the back-end voltage sampling circuit respectively. Therefore, the performing of the first state detection on the anti-reverse circuit based on the first sampling voltage is specifically: If the first front-end sampling voltage is the same as the first back-end sampling voltage, determine that the anti-reverse circuit is in a short-circuit state; If the first front-end sampling voltage is different from the first back-end sampling voltage, determine that the anti-reverse circuit is in an open-circuit state or a good state.

[0104] ForFigure 1 The circuit structure of the charging module shown, the voltage sampling circuit includes a front-end voltage sampling circuit and a back-end voltage sampling circuit. The front-end voltage sampling circuit includes voltage sampling circuit 1 and voltage sampling circuit 2, and the back-end voltage sampling circuit is voltage sampling circuit 3. The first front-end sampling voltage of the front-end voltage sampling circuit and the first back-end sampling voltage of the back-end voltage sampling circuit are obtained respectively. Specifically, the sampling voltage Vout1 is obtained through voltage sampling circuit 1, the sampling voltage Vout2 is obtained through voltage sampling circuit 2, and the sampling voltage Vout3 is obtained through voltage sampling circuit 3. The sampling voltages Vout1, Vout2, and Vout3 are the first sampling voltages. Among them, the sampling voltages Vout1 and Vout2 are the first front-end sampling voltages, and the sampling voltage Vout3 is the first back-end sampling voltage. Subsequently, the first state detection of the reverse protection circuit is performed based on the first sampling voltages. As Figure 5 shown, specifically, compare whether the first front-end sampling voltage (Vout1 or Vout2) and the first back-end sampling voltage Vout3 are consistent. If they are consistent, it is determined that the reverse protection circuit (reverse protection diode D10) is in a short-circuit state; if they are not consistent, it is determined that the reverse protection circuit (reverse protection diode D10) is in an open-circuit state or a good state.

[0105] For Figure 2 the circuit structure of the charging module shown, the voltage sampling circuit includes a front-end voltage sampling circuit and a back-end voltage sampling circuit. The front-end voltage sampling circuit includes voltage sampling circuit 1 and voltage sampling circuit 2, and the back-end voltage sampling circuit is voltage sampling circuit 3. The first front-end sampling voltage of the front-end voltage sampling circuit and the first back-end sampling voltage of the back-end voltage sampling circuit are obtained respectively. Specifically, the sampling voltage Vout1 is obtained through voltage sampling circuit 1, the sampling voltage Vout2 is obtained through voltage sampling circuit 2, and the sampling voltage Vout3 is obtained through voltage sampling circuit 3. The sampling voltages Vout1, Vout2, and Vout3 are the first sampling voltages. Among them, for the reverse protection diode D9, the sampling voltage Vout1 is the first front-end sampling voltage, and the sampling voltage Vout3 is the first back-end sampling voltage; for the reverse protection diode D10, the sampling voltage Vout2 is the first front-end sampling voltage, and the sampling voltage Vout3 is the first back-end sampling voltage. Subsequently, the first state detection of the reverse protection circuit is performed based on the first sampling voltages. As Figure 6As shown in the figure, specifically, for the reverse protection diode D9, compare whether the first front - end sampling voltage Vout1 is the same as the first back - end sampling voltage Vout3. If the first front - end sampling voltage Vout1 is the same as the first back - end sampling voltage Vout3, it is determined that the reverse protection diode D9 is in an open - circuit state. If the first front - end sampling voltage Vout1 is different from the first back - end sampling voltage Vout3, it is determined that the reverse protection diode D9 is in an open - circuit state or a good state. For the reverse protection diode D10, compare whether the first front - end sampling voltage Vout2 is the same as the first back - end sampling voltage Vout3. If the first front - end sampling voltage Vout2 is the same as the first back - end sampling voltage Vout3, it is determined that the reverse protection diode D10 is in an open - circuit state. If the first front - end sampling voltage Vout2 is different from the first back - end sampling voltage Vout3, it is determined that the reverse protection diode D10 is in an open - circuit state or a good state.

[0106] As an alternative implementation, obtaining the second sampling voltages of the respective voltage sampling circuits includes:

[0107] S311: Obtain the second front - end sampling voltage of the front - end voltage sampling circuit and the second back - end sampling voltage of the back - end voltage sampling circuit respectively;

[0108] Based on the second sampling voltages, performing a second - stage state detection on the reverse protection circuit and determining the state of the reverse protection circuit includes:

[0109] S321: If the second front - end sampling voltage is the same as the second back - end sampling voltage, determine that the reverse protection circuit is in a good state;

[0110] S322: If the second front - end sampling voltage is different from the second back - end sampling voltage, determine that the reverse protection circuit is in an open - circuit state.

[0111] Specifically, when obtaining the second sampling voltages of the respective voltage sampling circuits, obtain the second front - end sampling voltage of the front - end voltage sampling circuit and the second back - end sampling voltage of the back - end voltage sampling circuit respectively. In this way, when performing a second - stage state detection on the reverse protection circuit based on the second sampling voltages and determining the state of the reverse protection circuit, if the second front - end sampling voltage is the same as the second back - end sampling voltage, determine that the reverse protection circuit is in a good state; if the second front - end sampling voltage is different from the second back - end sampling voltage, determine that the reverse protection circuit is in an open - circuit state.

[0112] For Figure 1For the circuit structure of the charging module shown, when it is determined that the anti-reverse diode D10 is in an open-circuit state or a good state, a second state detection is performed on the anti-reverse circuit to obtain the second sampling voltages of each voltage sampling circuit. Again, the sampling voltage Vout1 is obtained through the voltage sampling circuit 1, the sampling voltage Vout2 is obtained through the voltage sampling circuit 2, and the sampling voltage Vout3 is obtained through the voltage sampling circuit 3. The sampling voltages Vout1, Vout2, and Vout3 obtained at this time are the second sampling voltages. Among them, Vout1 and Vout2 are the second front-end sampling voltages, and Vout3 is the second back-end sampling voltage. Subsequently, a second state detection is performed on the anti-reverse circuit based on the second sampling voltages. As Figure 5 shown, specifically, compare whether the second front-end sampling voltage (Vout1 or Vout2) is consistent with the second back-end sampling voltage Vout3. If they are consistent, it is determined that the anti-reverse circuit (anti-reverse diode D10) is in a good state; if they are not consistent, it is determined that the anti-reverse circuit (anti-reverse diode D10) is in an open-circuit state.

[0113] For Figure 2 the circuit structure of the charging module shown, when it is determined that the anti-reverse diode D9 is in an open-circuit state or a good state, a second state detection is performed on the anti-reverse circuit to obtain the second sampling voltages of each voltage sampling circuit. Again, the sampling voltage Vout1 is obtained through the voltage sampling circuit 1, and the sampling voltage Vout3 is obtained through the voltage sampling circuit 3. The sampling voltages Vout1 and Vout3 obtained at this time are the second sampling voltages. Among them, the sampling voltage Vout1 is the second front-end sampling voltage, and the sampling voltage Vout3 is the second back-end sampling voltage. Subsequently, a second state detection is performed on the anti-reverse circuit based on the second sampling voltages. As Figure 6 shown, specifically, compare whether the second front-end sampling voltage Vout1 is consistent with the second back-end sampling voltage Vout3. If they are consistent, it is determined that the anti-reverse diode D9 is in a good state; if they are not consistent, it is determined that the anti-reverse diode D9 is in an open-circuit state. When it is determined that the anti-reverse diode D10 is in an open-circuit state or a good state, a second state detection is performed on the anti-reverse circuit to obtain the second sampling voltages of each voltage sampling circuit. Again, the sampling voltage Vout2 is obtained through the voltage sampling circuit 2, and the sampling voltage Vout3 is obtained through the voltage sampling circuit 3. The sampling voltages Vout2 and Vout3 obtained at this time are the second sampling voltages. Among them, the sampling voltage Vout2 is the second front-end sampling voltage, and the sampling voltage Vout3 is the second back-end sampling voltage. Subsequently, a second state detection is performed on the anti-reverse circuit based on the second sampling voltages. As Figure 6 shown, specifically, compare whether the second front-end sampling voltage Vout2 is consistent with the second back-end sampling voltage Vout3. If they are consistent, it is determined that the anti-reverse diode D10 is in a good state; if they are not consistent, it is determined that the anti-reverse diode D10 is in an open-circuit state.

[0114] The second embodiment of the present application provides a charging module, and the charging module includes a controller. The controller is used to execute a voltage detection method of the charging module to perform fault detection on the reverse connection prevention circuit in the charging module.

[0115] The third embodiment of the present application provides a charging system, as Figure 7 shown. The charging system includes at least two charging modules 110, at least one charging interface 120, a control center 130, and a power distribution device 140. The power distribution device 140 is respectively connected to the control center 130, each charging module 110, and each charging interface 120.

[0116] Among them, each charging module 110 is used to convert the alternating current of the power grid into direct current and provide it to each charging interface 120; the control center 130 is used to obtain the required power of each charging interface, and generate a scheduling instruction according to the connection relationship of the controllable switches in the power distribution device and each required power; the power distribution device 140 is used to control the disconnection or closure of the controllable switches according to the scheduling instruction to distribute the output power of each charging module 110 to each charging interface.

[0117] In an optional implementation manner, the charging system provided by the embodiment of the present application is an integrated DC charging pile. The charging interface 120 is used to connect a charging gun, and the charging gun is hung on the host of the charging system through a gun holder on the charging system main body.

[0118] In an optional implementation manner, the charging system provided by the embodiment of the present application is a split-type DC charging pile. The charging system further includes a plurality of charging terminals. The charging interface 120 is used to connect the charging terminals. The charging terminals are separately arranged from the charging system main body. The charging terminals are configured with single charging guns or double charging guns and are used to output power to an electric vehicle.

[0119] When the controller in a certain charging module detects that the reverse connection prevention circuit in the charging module is in a fault state by executing the voltage detection method of the charging module, the charging module is removed from the charging system to ensure the reliable operation of the charging system.

[0120] Specifically, if the controller in a certain charging module determines that the reverse connection prevention circuit is in a fault state based on the detection result of the first state detection or the detection result of the second state detection by executing the voltage detection method of the charging module, the charging module where the reverse connection prevention circuit is located is removed from the charging system. Among them, the fault state includes an open circuit state and a short circuit state.

[0121] As Figure 4As shown, if the voltages at both ends of the reverse connection prevention circuit are the same in the detection result of the first state detection, it is determined that the reverse connection prevention circuit is in an open circuit state. Then, the charging module where the reverse connection prevention circuit is located is removed from the charging system, and the detection of this reverse connection prevention circuit is terminated. If the voltage drop rates at both ends of the reverse connection prevention circuit are the same in the detection result of the second state detection, it is determined that the reverse connection prevention circuit is in a short circuit state. Then, the charging module where the reverse connection prevention circuit is located is removed from the charging system.

[0122] As Figure 5 and Figure 6 shown, if the voltages at both ends of the reverse connection prevention circuit are the same in the detection result of the first state detection, it is determined that the reverse connection prevention circuit is in a short circuit state. Then, the charging module where the reverse connection prevention circuit is located is removed from the charging system, and the detection of this reverse connection prevention circuit is terminated. If the voltages at both ends of the reverse connection prevention circuit are different in the detection result of the second state detection, it is determined that the reverse connection prevention circuit is in an open circuit state. Then, the charging module where the reverse connection prevention circuit is located is removed from the charging system.

[0123] As Figure 8 shown, for the single-module connected load, one charging module is connected to an external load through a load contactor K1. In this application scenario, when it is detected that the reverse connection prevention circuit is in a fault state, the load contactor K1 is directly disconnected to stop the charging operation.

[0124] As Figure 9 shown, for the multi-module connected load, which includes N charging modules (N≥2), these charging modules are connected in parallel and then connected to an external load through a load contactor K1. In this application scenario, when it is detected that the reverse connection prevention circuit of a certain charging module is in a fault state, that is, in an open circuit state or a short circuit state, the corresponding charging module is removed from the charging system to enable other normal modules to continue working, or further detect the state of the reverse connection prevention circuits of other modules.

[0125] Through a timely fault handling mechanism, system safety problems caused by the failure of the reverse connection prevention diode can be effectively prevented, ensuring the reliable operation of the charging system.

[0126] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application accordingly. Any equivalent structural or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be equally included in the patent protection scope of the present application.

Claims

1. A voltage detection method for a charging module, characterized in that: The charging module includes a cascaded AC / DC unit and a DC / DC unit, the DC / DC unit includes a plurality of output circuits and an anti-reverse circuit, each of the output circuits is connected to a load via the anti-reverse circuit, and both the input and output ends of the anti-reverse circuit are provided with a voltage sampling circuit; the method includes: Controlling the DC / DC unit to a first preset state; Performing a first state detection on the anti-reverse circuit based on the sampling voltages of each voltage sampling circuit; If the result of the first state detection fails to determine the state of the anti-reverse circuit, the DC / DC unit is controlled to a second preset state, and a second state detection is performed on the anti-reverse circuit based on the current sampling voltage of each voltage sampling circuit to determine the state of the anti-reverse circuit.

2. The method according to claim 1, characterized in that The step of controlling the DC / DC unit to be in a first preset state includes: Controlling the DC / DC unit to start and disconnect the load; The first state detection of the anti-reverse circuit based on the sampled voltages of each voltage sampling circuit includes: Acquire a first sampling voltage of each of the voltage sampling circuits, and perform a first state detection on the anti-reverse circuit based on the first sampling voltage; The controlling the DC / DC unit to be in a second preset state includes: Controlling the DC / DC unit to be turned off, and obtaining the second sampling voltage of each of the voltage sampling circuits; The second state detection of the anti-reverse circuit based on the current sampling voltage of each voltage sampling circuit and determining the state of the anti-reverse circuit includes: Determining a voltage drop speed of each of the voltage sampling circuits based on the first sampling voltage and the second sampling voltage; A second state detection is performed on the anti-reverse circuit based on the voltage drop speed of each voltage sampling circuit to determine the state of the anti-reverse circuit.

3. The method according to claim 2, characterized in that The plurality of voltage sampling circuits include a front-end voltage sampling circuit located at the input side of the anti-reverse circuit and a rear-end voltage sampling circuit located at the output side of the anti-reverse circuit; The obtaining of the first sampled voltage of each of the voltage sampling circuits comprises: Respectively acquiring a first front-end sampling voltage of the front-end voltage sampling circuit and a first rear-end sampling voltage of the rear-end voltage sampling circuit; The first state detection of the anti-reverse circuit based on the first sampling voltage includes: If the first front-end sampling voltage is the same as the first back-end sampling voltage, determining that the anti-reverse circuit is in a good state or a short-circuit state; If the first front-end sampling voltage is different from the first rear-end sampling voltage, it is determined that the anti-reverse circuit is in an open circuit state.

4. The method according to claim 3, characterized in that: The step of determining the voltage drop speed of each of the voltage sampling circuits based on the first sampling voltage and the second sampling voltage comprises: Determining a sampling voltage drop speed of the front-end voltage sampling circuit and a sampling voltage drop speed of the back-end voltage sampling circuit based on the first sampling voltage and the second sampling voltage; The second state detection of the anti-reverse circuit based on the voltage drop speed of each voltage sampling circuit and determining the state of the anti-reverse circuit includes: Comparing whether a sampling voltage drop speed of the front-end voltage sampling circuit is the same as a sampling voltage drop speed of the back-end voltage sampling circuit; If the sampling voltage drop speed of the front-end voltage sampling circuit is the same as the sampling voltage drop speed of the back-end voltage sampling circuit, it is determined that the anti-reverse circuit is in a short-circuit state; If the sampling voltage drop speed of the front-end voltage sampling circuit is different from the sampling voltage drop speed of the back-end voltage sampling circuit, it is determined that the anti-reverse circuit is in a good state.

5. The method according to claim 1, characterized in that The step of controlling the DC / DC unit to be in a first preset state includes: Controlling the AC / DC unit to start and controlling the DC / DC unit to shut down and connect to the load; The first state detection of the anti-reverse circuit based on the sampled voltages of each voltage sampling circuit includes: Acquire a first sampling voltage of each of the voltage sampling circuits, and perform a first state detection on the anti-reverse circuit based on the first sampling voltage; The controlling the DC / DC unit to be in a second preset state includes: Disconnecting the load and controlling the DC / DC unit to start, and obtaining the second sampling voltage of each voltage sampling circuit; The second state detection of the anti-reverse circuit based on the current sampling voltage of each voltage sampling circuit and determining the state of the anti-reverse circuit includes: A second state detection is performed on the anti-reverse circuit based on the second sampling voltage to determine the state of the anti-reverse circuit.

6. The method according to claim 5, characterized in that The charging module further includes a relay combination circuit, and the relay combination circuit is connected between the output circuit and the anti-reverse circuit; Before acquiring the first sampling voltage of each of the voltage sampling circuits and performing a first state detection on the anti-reverse circuit based on the first sampling voltage, the method further includes: Controlling the relay combination circuit to be in an off state so that the output circuit and the subsequent circuit are in an open circuit state and connected to a load; Obtaining a load voltage across the load; comparing the load voltage with a maximum output voltage of the output circuit; If the load voltage is greater than the maximum output voltage, disconnecting the load; If the load voltage is less than or equal to the maximum output voltage, the output circuits are controlled to be connected in series through the relay combination circuit.

7. The method according to claim 5, characterized in that The obtaining of the first sampled voltage of each of the voltage sampling circuits comprises: Respectively acquiring a first front-end sampling voltage of the front-end voltage sampling circuit and a first rear-end sampling voltage of the rear-end voltage sampling circuit; The first state detection of the anti-reverse circuit based on the first sampling voltage includes: If the first front-end sampling voltage is the same as the first rear-end sampling voltage, determining that the anti-reverse circuit is in a short-circuit state; If the first front-end sampling voltage is different from the first back-end sampling voltage, it is determined that the anti-reverse circuit is in an open circuit state or a good state.

8. The method according to claim 7, characterized in that The obtaining of the second sampled voltage of each of the voltage sampling circuits comprises: Respectively acquiring a second front-end sampling voltage of the front-end voltage sampling circuit and a second rear-end sampling voltage of the rear-end voltage sampling circuit; The performing a second state detection on the anti-reverse circuit based on the second sampling voltage and determining the state of the anti-reverse circuit includes: If the second front-end sampling voltage is the same as the second back-end sampling voltage, it is determined that the anti-reverse circuit is in a good state; If the second front-end sampling voltage is different from the second back-end sampling voltage, it is determined that the anti-reverse circuit is in an open circuit state.

9. A charging module, comprising a controller, wherein the controller is used to execute the voltage detection method of the charging module according to any one of claims 1 to 8 to perform fault detection on an anti-reverse circuit in the charging module.

10. A charging system, characterized in that: The device comprises at least two charging modules as claimed in claim 9, at least one charging interface, a control center and a power distribution device; the power distribution device is respectively connected to the control center, each charging module and each charging interface; Wherein, each of the charging modules is used to convert the AC power of the power grid into DC power and provide it to each of the charging interfaces; The control center is used to obtain the required power of each charging interface, and generate a scheduling instruction according to the connection relationship of the controllable switches in the power distribution device and each required power; The power distribution device is used to control the opening or closing of the controllable switch according to the scheduling instruction to distribute the output power of each charging module to each charging interface.

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