Design method of industrial-grade high-voltage monitoring automatic fool-proof circuit

Abstract

The invention discloses a design method of an industrial-grade high-voltage monitoring automatic fool-proof circuit, and relates to the technical field of photovoltaic cell assembly monitoring, the automatic fool-proof circuit comprises a high-voltage screening circuit, a high-voltage disconnection circuit and a high-voltage comparison circuit, the series number of the three circuits is determined by the series-connection series number i of photovoltaic cell assemblies of a series-connection photovoltaic power station, the voltage input ends connected in series with the photovoltaic cell assemblies are in a disordered state; the high-voltage screening circuit is provided with i stages, and each stage of high-voltage screening circuit is used for screening out maximum values of all input voltages which are not disconnected at the stage; the high-voltage disconnection circuit is provided with i-1 stages, and each stage of high-voltage disconnection circuit is used for automatically disconnecting all high-voltage inputs greater than or equal to the maximum voltage screened out by the previous stage of high-voltage screening circuit and does not participate in the comparison of the high-voltage maximum value of the stage; the high-voltage comparison circuit is provided with i-1 stages, and each stage of the high-voltage comparison circuit is used for enabling all screened voltage values except the voltage values lower than the voltage of the previous stage to participate in the maximum voltage comparison of the stage.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic cell assembly monitoring, and in particular to a design method for an industrial-grade high-voltage monitoring automatic fool-proofing circuit. Background Art

[0002] At present, when fine-tuning the management of photovoltaic power stations, it is necessary to monitor the voltage and current of each panel, the temperature before and after the panel, and the on-site wind speed. These data are important bases for monitoring the operation status and fault judgment of photovoltaic power stations. Photovoltaic modules can be shielded for a short time, but long-term partial shielding will produce a heat island effect, the panels will heat up, and long-term accumulation of heat may physically damage the photovoltaic solar modules. These characteristics will affect the output power and voltage of a single photovoltaic module, so it is necessary to monitor the voltage of photovoltaic cell modules.

[0003] In the field of photovoltaic power station operation, in order to meet the power generation needs, multiple groups of solar photovoltaic modules are often required to generate electricity in series. In order to monitor the working status of each photovoltaic module at all times, it is necessary to collect the working voltage of each solar photovoltaic module in real time. In the actual engineering practice, the monitoring voltage collection heads of each photovoltaic solar cell module are usually placed in a disorderly manner. Once the connection order of the collection heads of a series circuit in the monitoring collection circuit is disordered, the consequences will be very serious. Summary of the invention

[0004] In view of the above technical problems, the present invention provides a design method for an industrial-grade high-voltage monitoring automatic fool-proof circuit, which is mainly used in the case where monitoring heads are not arranged in order in voltage monitoring of series-connected photovoltaic modules in a battery module series connection group.

[0005] In order to solve the above technical problems, the technical solution proposed by the present invention is: A design method for an industrial-grade high-voltage monitoring automatic fool-proof circuit includes a high-voltage screening circuit, a high-voltage disconnection circuit, and a high-voltage comparison circuit. The number of the high-voltage screening circuit, the high-voltage disconnection circuit, and the high-voltage comparison circuit is determined by the number of series-connected photovoltaic cell assemblies in a photovoltaic power station, i, where i is an integer, and the voltage input terminals of the photovoltaic cell assemblies in series are in a disordered state. The high-voltage screening circuit is provided with i levels, and each level of the high-voltage screening circuit is used to screen out the maximum value of all input voltages that are not disconnected at this level; The high-voltage disconnection circuit is provided with i-1 levels, and each level of the high-voltage disconnection circuit is used to disconnect all high-voltage inputs that are greater than or equal to the maximum voltage value screened out by the previous level of high-voltage screening circuit, and do not participate in the high-voltage maximum value comparison of this level; The high-voltage comparison circuit is provided with i-1 stages, and each stage of the high-voltage comparison circuit is used to screen out all voltage values ​​lower than the maximum voltage screened out by the previous stage of the high-voltage screening circuit to participate in the maximum voltage comparison of this stage.

[0006] As a further improvement of the above technical solution: Preferably, the foolproof circuit includes an i-level high-voltage screening circuit, an i-1-level high-voltage disconnection circuit and an i-1-level high-voltage disconnection circuit. The high-voltage screening circuit of the first level independently screens out the maximum value of all input voltages. The high-voltage screening circuit of each subsequent level is connected to the corresponding high-voltage disconnection circuit, and the high-voltage disconnection circuit of each level is connected to the corresponding high-voltage comparison circuit of the first level, and the high-voltage disconnection circuit of the first level is connected to the high-voltage screening circuit of the second level, and so on, until the high-voltage disconnection circuit of the i-1-level is connected to the high-voltage screening circuit of the i-level, and the series disordered input voltage of the photovoltaic modules of the photovoltaic power station is connected to the high-voltage screening circuit of the first level, and is connected to the reverse input terminal of the high-voltage comparison circuit of each level and the high-voltage disconnection circuit of each level; The high-voltage comparison circuit of this stage will screen out all input voltages lower than the extremely high voltage of the previous stage, and control the output voltage of the emitter follower drive circuit through the output voltage value of the voltage comparator, thereby controlling the closing or opening of the high-voltage disconnect circuit of this stage, allowing all voltages lower than the extremely high voltage of the previous stage to be compared with the voltage of this stage, and disconnecting all voltage input terminals that are greater than or equal to the extremely high voltage value of the previous stage, prohibiting them from participating in the comparison of the maximum voltage of this stage.

[0007] Preferably, the i-th level high-voltage screening circuit includes i diodes and a resistor, all diodes have a common cathode connected in parallel, and after the i diodes are connected in parallel, their common cathode is connected in series with the resistor, the anodes of the diodes in the first-level high-voltage screening circuit are respectively connected to the series disordered input voltage of the photovoltaic module, and the anodes of the remaining high-voltage screening circuit diodes are respectively connected to the delayed closing contacts of the time relays of the corresponding high-voltage disconnect circuits.

[0008] Preferably, the high-voltage comparison circuit of each stage includes i high-voltage proportional reduction circuits, i voltage comparators, and i groups of emitter follower drive combinations, wherein the high-voltage proportional reduction circuit is used to proportionally reduce the voltage of all high voltages and then compare the voltages through the voltage comparator; the emitter follower drive combination is used to drive the corresponding high-voltage disconnection circuit of the next stage; 1 high-voltage proportional reduction circuit, 1 voltage comparator, and 1 group of emitter follower drive combinations constitute a high-voltage comparison circuit, whose inputs correspond to different disordered input voltages and the maximum voltage output by the previous stage high-voltage screening circuit.

[0009] Preferably, the high-voltage proportional reduction circuit comprises two groups of proportionally reduced resistors, each group comprising two resistors connected in series, wherein the input end of one group of series resistors is connected to the extremely high voltage output by the high-voltage screening circuit of the previous stage, the other end is grounded, and the center connection point of the two series resistors is connected to the same-phase input end of the voltage comparator; the input end of the other group of series resistors is connected to any non-repetitive disordered voltage input end, the other end is grounded, and the center connection point of the two series resistors is connected to the inverting input end of the voltage comparator; the positive power supply input end of the voltage comparator is connected to the positive pole of the power supply, the negative power supply input end is grounded, and a pull-up resistor is connected between the pin of the positive power supply input end and the pin of the output end.

[0010] Preferably, the emitter follower drive combination includes a transistor, a voltage regulator diode, and two resistors; one end of one of the resistors is connected to the output end of the voltage comparator, and the other end is respectively connected to the cathode of the voltage regulator diode and the base of the transistor; the anode of the voltage regulator diode is grounded, the collector of the transistor is connected to the power supply, the emitter of the transistor is connected to another resistor and then to the ground, and the emitter is also connected to one end of the control coil of the i-th level time relay of the corresponding high-voltage disconnect circuit of this level.

[0011] Preferably, the high-voltage disconnect circuit of each level includes i time relays, one end of the control coil of each time relay is connected to the emitter of the emitter follower drive combination transistor of the i-th level in the high-voltage comparison circuit of the same level, and the other end is grounded; one end of the delayed closing contact of each time relay is connected to any non-repetitive disordered voltage input terminal, and the other end of the delayed closing contact is respectively connected to the diode anode of the high-voltage screening circuit of the corresponding next level.

[0012] Preferably, the fool-proofing circuit is also provided with its own power supply circuit, which is supplied by an emitter follower, and the emitter follower is composed of a voltage-stabilizing diode, a transistor and two resistors. The cathode of the voltage-stabilizing diode is respectively connected to one of the resistors and the base of the transistor, and the anode of the voltage-stabilizing diode is grounded. The cathode of the voltage-stabilizing diode is connected to the resistor and then connected to the highest voltage end of the output of the first-level high-voltage screening circuit; the emitter of the transistor is connected to another resistor and then grounded, and the emitter of the transistor is also connected to the output end, which is the positive electrode of the power supply of the overall circuit, and the collector of the transistor is connected to the highest voltage end of the output of the first-level high-voltage screening circuit.

[0013] Compared with the prior art, the design method of the industrial-grade high-voltage monitoring automatic fool-proof circuit provided by the present invention has the following advantages: (1) The design method of the industrial-grade high-voltage monitoring automatic fool-proof circuit of the present invention automatically sorts and outputs the high-voltage monitoring heads of disordered series-connected photovoltaic modules in descending order of voltage value. The overall circuit is not affected by the number of series-connected stages, and there is no upper limit on the maximum peak value of the total series voltage. It can be applied to large-scale centralized photovoltaic power stations or small-scale distributed photovoltaic power stations, and its application can be extended to any application occasions that require series-connected monitoring of battery groups.

[0014] (2) The design method of the industrial-grade high-voltage monitoring automatic fool-proof circuit of the present invention can accurately output the voltage value of each node of the series photovoltaic module circuit in sequence after the identification and sorting of the fool-proof circuit, regardless of how the connection sequence of the connectors is disordered. The present invention has universal applicability, and by adjusting the number of stages of the identification circuit, it can adapt to any series high-voltage battery group circuit with a single-stage voltage higher than 12V. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the disordered voltage input circuit of the present invention.

[0016] Figure 2 This is the circuit diagram of the first-level high-voltage screening circuit of the present invention.

[0017] Figure 3 This is an emitter follower circuit diagram of the power supply of the present invention.

[0018] Figure 4 This is the circuit diagram of the first high-voltage comparison circuit of the present invention.

[0019] Figure 5 This is a circuit diagram of the first high-voltage comparison circuit of the second part of the present invention.

[0020] Figure 6 This is the circuit diagram of the first high-voltage comparison circuit of the third part of the present invention.

[0021] Figure 7 This is the circuit diagram of the fourth first high-voltage comparison circuit of the present invention.

[0022] Figure 8 This is a diagram of the first high-voltage disconnection circuit and the second high-voltage automatic screening circuit of the present invention. DETAILED DESCRIPTION

[0023] The specific implementation methods of the present invention are described in detail below. It should be understood that the described embodiments are only some embodiments of the present invention, not all. Based on these examples, those skilled in the art can understand and implement all other possible implementation methods of the present technical solution without performing creative work, and these implementation methods also belong to the protection scope of the present technical solution. The protection of the present technical solution is not limited to the specific embodiments described in the text, but also includes all equivalent implementation methods, which are all organic parts of the present invention.

[0024] The present invention provides a design method for an industrial-grade high-voltage monitoring automatic fool-proof circuit. The fool-proof circuit comprises a high-voltage screening circuit, a high-voltage disconnection circuit and a high-voltage comparison circuit. The number of levels of the high-voltage screening circuit, the high-voltage disconnection circuit and the high-voltage comparison circuit is determined by the number of levels of photovoltaic battery components in a series photovoltaic power station. If an i-pole battery component is connected in series, the high-voltage screening circuit is at level i, the high-voltage disconnection circuit is at level i-1 and the high-voltage comparison circuit is at level i-1.

[0025] like Figure 1 As shown, since the circuit of the present invention has universal applicability, this embodiment takes a 4-level 12V serial anti-fool circuit as an example for explanation, and the working principles of other circuits are similar to this circuit. All component numbers mentioned below in this embodiment are the components involved in the 4-level-12V.

[0026] Assume that V5, V6, V7, and V8 are four photovoltaic cell modules connected in series, K69, K70, K71, and K72 are single-pole four-throw switches, and the series disordered input voltage of the photovoltaic modules of the photovoltaic power station is controlled by the disordered combination input of switches K69, K70, K71, and K72.

[0027] In this embodiment, the high-voltage screening circuit has four levels, and each level of the high-voltage screening circuit is used to screen out the maximum value of all input voltages that have not been disconnected at this level. The high-voltage disconnection circuit has three levels, and the previous level of the high-voltage screening circuit screens out the maximum voltage value max x Each high voltage disconnect circuit is used to connect all ≥ max x The high-voltage input is automatically disconnected and does not participate in the high-voltage maximum value comparison of this level. The high-voltage comparison circuit has three levels. First, a voltage value lower than the voltage of the previous level is selected, and this voltage value is removed. The remaining voltage value passes through the high-voltage comparison circuit of the current level and participates in the maximum value voltage comparison of this level. That is, each level of high-voltage comparison circuit only allows the voltage signal with input voltage < the maximum value selected by the previous level to participate in the maximum value comparison of this level.

[0028] In this embodiment, the series disordered input voltage of the photovoltaic modules of the photovoltaic power station is controlled by the disordered combination of switches K69, K70, K71, and K72; the disordered input voltage is represented by four voltages v0, v1, v2, and v3. The same v0 is a voltage value, and similarly, the same v1, the same v2, and the same v3 are all the same voltage value.

[0029] The four-level high-voltage screening circuits are respectively a first high-voltage screening circuit, a second high-voltage screening circuit, a third high-voltage screening circuit, and a fourth high-voltage screening circuit, and have the same structure.

[0030] like Figure 2 As shown, the first high voltage screening circuit is taken as an example for explanation. The first high voltage screening circuit includes a diode and a resistor. S43, S51, S53, and S61 are four diodes, and the common cathode is connected in parallel; after the four diodes S43, S51, S53, and S61 are connected in parallel, their common cathode is connected in series with the resistor R3.

[0031] In any high-voltage screening circuit, assume that the forward conduction voltage drop of all diodes is 0, the highest voltage at the input end is vx, the diode connected to vx is Sx, and at the same time, assume that a voltage value vy smaller than vx is first turned on through the diode Sy connected to vy, then the cathode voltage at the Sy end is vy. Because the cathode of Sx is short-circuited with the cathode of Sy, in this case the cathode voltage of Sx must also be vy, and because vx is greater than vy, Sx must be turned on, and at this time the cathode voltage of Sx will immediately increase to the maximum voltage vx, and vx>vy, so Sy must be cut off, the voltage at the vy input end is reversely cut off and disconnected by Sy, and the common cathode output voltage of diodes Sx and Sy must be the maximum value vx. Among them, x and y represent numbers.

[0032] Therefore, the non-repetitive disordered voltage will output the highest voltage max0 after passing through the first high-voltage screening circuit composed of S43, S51, S53, S61, and R3.

[0033] like Figure 8 As shown, the high-voltage disconnection circuit is provided with a first high-voltage disconnection circuit, a second high-voltage disconnection circuit, and a third high-voltage disconnection circuit, and the first high-voltage disconnection circuit is taken as an example for explanation. The first high-voltage disconnection circuit includes time relays J29, J36, J43, and J50, one end of the control coil of each time relay is connected to the emitter of the high-voltage comparison circuit transistor, and the other end is grounded. At the same time, one end of the delayed closing contact of each time relay is connected to the non-repetitive disordered voltage input end of the photovoltaic cell assembly connected in series in any photovoltaic power station, and the other end of the delayed closing contact is respectively connected to the diode anode S40, S48, S58, and S66 of the corresponding second high-voltage screening circuit.

[0034] The high-voltage comparison circuit includes a first high-voltage comparison circuit, a second high-voltage comparison circuit, and a third high-voltage comparison circuit, which have the same structure. The first high-voltage comparison circuit is taken as an example for description. Figures 4 to 7 As shown, the first high-voltage comparison circuit includes 4 high-voltage proportional reduction circuits, 4 voltage comparators, and 4 emitter follower drive combinations, wherein the function of the high-voltage proportional reduction circuit is to reduce all high voltages and then compare the voltages through the voltage comparator, otherwise the voltage comparator chip will be directly burned. The emitter follower drive combination is used to drive the control coil of the time relay in the corresponding high-voltage disconnection circuit of the subsequent stage. 1 high-voltage proportional reduction circuit, 1 voltage comparator, and 1 emitter follower drive combination constitute a first high-voltage comparison circuit. In this embodiment, there are 4 levels of disordered input voltages, so there are 4 high-voltage comparison circuits in each level, and their structures are similar. The only difference is that the voltages connected to the reverse input end of the voltage comparator are disordered input voltages v0, v1, v2, and v3, respectively, and the high-voltage disconnection circuit driven by the transistor emitter of the emitter follower drive combination is different.

[0035] Furthermore, if Figure 4 As shown, each high-voltage proportional reduction circuit includes 2 groups of proportional resistors, and the proportional resistors are the same as the ratio of the voltage reduced by the reverse input terminal and the voltage reduced by the in-phase terminal. Each group includes 2 resistors in series, and the input end of one group of series resistors R42 and R75 is connected to the highest voltage max0 output by the first high-voltage screening circuit, and the other end is grounded. The center of the two resistors connected in series is connected to the in-phase input end of the voltage comparator U1A. The input end of the other group of series resistors R125 and R192 is connected to the non-repetitive disordered voltage input end of any photovoltaic cell assembly in series, and in this embodiment, the first high-voltage comparison circuit is connected to v0; the other end is grounded, and the center of the two resistors R125 and R192 connected in series is connected to the inverting input end of the voltage comparator U1A. The positive power input end of the voltage comparator U1A is connected to the power supply vcc, and the negative power input end is grounded. The pull-up resistor R59 is connected between the pin of the positive power input end and the pin of the output end to ensure the normal operation of the operational amplifier.

[0036] The emitter follower drive combination includes a transistor Q2, a voltage regulator diode D2, a resistor R76, and a resistor R153; one end of the resistor R76 is connected to the output end of the voltage comparator U1A, and the other end is respectively connected to the cathode of the voltage regulator diode D2 and the base of the transistor Q2; the anode of the voltage regulator diode D2 is grounded, the collector of the transistor Q2 is connected to the positive electrode vcc of the power supply, and the emitter of the transistor Q2 is grounded (GND) through the resistor R153. At the same time, the emitter is also connected to one end of the control coil of the time relay corresponding to the first high-voltage disconnect circuit, and the other end of the control coil of the corresponding time relay is grounded.

[0037] In this embodiment, the coils of the four normally open time relays J29, J36, J43, and J50 of the first high-voltage disconnect circuit are respectively controlled by four first high-voltage comparison circuits. Only when the voltage value of the disordered input voltages v0, v1, v2, and v3 is lower than the maximum voltage value max0, the corresponding normally open time relays will produce a power-on delay attraction action, that is, the voltage participating in the voltage comparison of this level is always controlled to be smaller than the maximum voltage of the previous level.

[0038] like Figure 3 As shown, the foolproof circuit is also provided with its own power supply circuit, the working voltage of which is supplied by an emitter follower, which is composed of R1, R2, D1, and Q1, wherein the cathode of the voltage zener diode D1 is connected to the resistor R1 and the base of the transistor Q1, the anode of the voltage zener diode D1 is grounded, the emitter of the transistor Q1 is connected to the resistor R2 and then to the ground, and the emitter of the transistor Q1 is also connected to the power supply voltage of its own circuit, and outputs the power supply vcc. The collector of the transistor Q1 is connected to the highest voltage terminal max0 output by the first high-voltage screening circuit; the cathode of the voltage zener diode D1 is connected to the resistor R1 and then to the highest voltage output terminal max0 of the first high-voltage screening circuit.

[0039] When the foolproof circuit of the present invention is used, Figure 1 As shown, assuming that the output voltage of K69 is v2, the output voltage of K70 is v0, the output voltage of K71 is v3, and the output voltage of K72 is v1, the output ends of the four disordered switch combinations K69, K70, K71, and K72 are respectively connected to the anodes of diodes S43, S51, S53, and S61. Through the first high-voltage screening circuit, the highest voltage max0 can be output at the cathodes of the four diodes and output at the non-grounded end of the resistor R3. The other end of the resistor R3 is connected to the common cathode of the common cathode diodes S43, S51, S53, and S61.

[0040] The disordered input voltage will output the highest voltage max0 after passing through the first high-voltage screening circuit composed of S43, S51, S53, S61, and R3, that is, the highest voltage max0 is separated. The max0 voltage passes through the emitter follower composed of R1, D1, Q1, and R2, and outputs a stable DC voltage vcc to power the foolproof circuit itself.

[0041] Furthermore, after separating the highest voltage max0, the input non-repetitive disordered voltage passes through four high-voltage proportional reduction circuits and voltage comparators, and is compared with the maximum voltage max0. Only the voltage comparator connected to the three disordered input voltages smaller than the highest voltage max0 will output a high level, thereby driving the transistor in the emitter follower drive combination connected to it to conduct, so that the normally open time relay in the corresponding high-voltage screening circuit is energized; and the transistor in the emitter follower drive combination corresponding to the same input voltage end as max0 will be cut off, and then the output of its emitter end will be low level, so that the time relay control coil of the high-voltage disconnection circuit connected to it cannot be driven to work. Therefore, the voltages involved in the first-level comparison are only the other three input voltages lower than max0, and then the second highest voltage value max1 lower than max0 is compared and screened out through the second high-voltage screening circuit.

[0042] In the screening process of the second high voltage, firstly, all voltages lower than max0 are selected through the first high voltage comparison circuit, and then the emitter voltage of the transistor of the emitter follower drive combination in the corresponding high voltage comparison circuit is controlled to control the on and off of the control coil of the time relay of the first high voltage disconnection circuit, and then the delayed closing contact of the corresponding time relay in the first high voltage disconnection circuit is controlled to be closed, so as to achieve the purpose of performing the second level comparison on all voltages smaller than the max0 voltage value, and finally the second highest voltage value max1 smaller than max0 is screened out through the second high voltage screening circuit.

[0043] Similarly, the third high-voltage screening circuit screens out the third highest voltage value max2 which is lower than max1. By keeping the two normally open time relays connected to the voltage value greater than or equal to max1 disconnected, they are prohibited from participating in the third-level voltage comparison, and the third highest voltage value max2 is screened out by comparison. The fourth high-voltage screening circuit screens out the fourth highest voltage value max3 which is lower than max2, so the final voltage output result of the entire circuit is max0>max1>max2>max3.

[0044] Through the fool-proof circuit of the present invention, the high-voltage monitoring heads of disordered series-connected photovoltaic modules can be automatically sorted and output in descending order of voltage value. The overall circuit is not affected by the number of series-connected photovoltaic modules, and there is no upper limit on the maximum peak value of the total series voltage. It can be applied to large-scale centralized photovoltaic power stations or small-scale distributed photovoltaic power stations, and the application can be extended to any application occasions that require series monitoring of battery groups.

[0045] The above implementation cases are only preferred embodiments of the present invention and are not intended to limit the present invention in any form. Although the present invention has been disclosed as above with preferred embodiments, they are not intended to limit the present invention. Therefore, any simple modification, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A design method for an industrial-grade high-voltage monitoring automatic fool-proofing circuit, characterized in that: It includes a high-voltage screening circuit, a high-voltage disconnection circuit, and a high-voltage comparison circuit. The number of the high-voltage screening circuit, the high-voltage disconnection circuit, and the high-voltage comparison circuit is determined by the number of series-connected photovoltaic cell assemblies in the photovoltaic power station, i, where i is an integer, and the voltage input end of the photovoltaic cell assemblies connected in series is in a disordered state; The high-voltage screening circuit is provided with i levels, and each level of the high-voltage screening circuit is used to screen out the maximum value of all input voltages that are not disconnected at this level; The high-voltage disconnection circuit is provided with i-1 levels, and each level of the high-voltage disconnection circuit is used to disconnect all high-voltage inputs that are greater than or equal to the maximum voltage value screened out by the previous level of high-voltage screening circuit, and do not participate in the high-voltage maximum value comparison of this level; The high-voltage comparison circuit is provided with i-1 stages, and each stage of the high-voltage comparison circuit is used to screen out all voltage values ​​lower than the maximum voltage screened out by the previous stage of the high-voltage screening circuit to participate in the maximum voltage comparison of this stage.

2. The design method of the industrial-grade high-voltage monitoring automatic fool-proofing circuit according to claim 1 is characterized in that: The foolproof circuit includes an i-level high-voltage screening circuit, an i-1-level high-voltage disconnection circuit and an i-1-level high-voltage disconnection circuit. The first-level high-voltage screening circuit independently screens out the maximum value of all input voltages, and each subsequent level of high-voltage screening circuit is connected to the corresponding high-voltage disconnection circuit, and each level of high-voltage disconnection circuit is connected to the corresponding level 1 high-voltage comparison circuit, and the level 1 high-voltage disconnection circuit is connected to the level 2 high-voltage screening circuit, and so on, until the i-1-level high-voltage disconnection circuit is connected to the i-level high-voltage screening circuit, the series disordered input voltage of the photovoltaic modules of the photovoltaic power station is connected to the level 1 high-voltage screening circuit, and is connected to the reverse input end of each level of the high-voltage comparison circuit and the high-voltage disconnection circuit of each level; The high-voltage comparison circuit of this stage will screen out all input voltages lower than the extremely high voltage of the previous stage, and control the output voltage of the emitter follower drive circuit through the output voltage value of the voltage comparator, thereby controlling the closing or opening of the high-voltage disconnect circuit of this stage, allowing all voltages lower than the extremely high voltage of the previous stage to be compared with the voltage of this stage, and disconnecting all voltage input terminals that are greater than or equal to the extremely high voltage value of the previous stage, prohibiting them from participating in the comparison of the maximum voltage of this stage.

3. The design method of the industrial-grade high-voltage monitoring automatic fool-proofing circuit according to claim 2 is characterized in that: The i-th level high-voltage screening circuit includes i diodes and a resistor. All diodes have a common cathode connected in parallel. After the i diodes are connected in parallel, their common cathode is connected in series with the resistor. The anodes of the diodes in the first-level high-voltage screening circuit are respectively connected to the series disordered input voltage of the photovoltaic module, and the anodes of the remaining high-voltage screening circuit diodes are respectively connected to the delayed closing contacts of the time relays of the corresponding high-voltage disconnect circuits.

4. The design method of the industrial-grade high-voltage monitoring automatic fool-proofing circuit according to claim 3 is characterized in that: The high-voltage comparison circuit of each stage includes i high-voltage proportional reduction circuits, i voltage comparators, and i groups of emitter follower drive combinations, wherein the high-voltage proportional reduction circuit is used to proportionally reduce all high voltages and then compare the voltages through the voltage comparator; the emitter follower drive combination is used to drive the corresponding high-voltage disconnection circuit of the subsequent stage; 1 high-voltage proportional reduction circuit, 1 voltage comparator, and 1 group of emitter follower drive combinations constitute a high-voltage comparison circuit, whose inputs correspond to different disordered input voltages and the maximum voltage output by the previous stage high-voltage screening circuit.

5. The design method of the industrial-grade high-voltage monitoring automatic fool-proofing circuit according to claim 4 is characterized in that: The high-voltage proportional reduction circuit includes two groups of proportional reduction resistors, each group includes two resistors connected in series, the input end of one group of series resistors is connected to the extremely high voltage output by the high-voltage screening circuit of the previous stage, the other end is grounded, and the center connection point of the two series resistors is connected to the same-phase input end of the voltage comparator; the input end of the other group of series resistors is connected to any non-repetitive disordered voltage input end, the other end is grounded, and the center connection point of the two series resistors is connected to the inverting input end of the voltage comparator; the positive power supply input end of the voltage comparator is connected to the positive pole of the power supply, the negative power supply input end is grounded, and a pull-up resistor is connected between the pin of the positive power supply input end and the pin of the output end.

6. The design method of the industrial-grade high-voltage monitoring automatic fool-proofing circuit according to claim 4 is characterized in that: The emitter follower drive combination includes a transistor, a voltage regulator diode, and two resistors; one end of one of the resistors is connected to the output end of the voltage comparator, and the other end is respectively connected to the cathode of the voltage regulator diode and the base of the transistor; the anode of the voltage regulator diode is grounded, the collector of the transistor is connected to the power supply, the emitter of the transistor is connected to another resistor and then to the ground, and the emitter is also connected to one end of the control coil of the i-th level time relay of the corresponding high-voltage disconnect circuit of this level.

7. The design method of the industrial-grade high-voltage monitoring automatic fool-proofing circuit according to claim 3 is characterized in that: Each level of the high-voltage disconnect circuit includes i time relays, one end of the control coil of each time relay is connected to the emitter of the i-th level emitter follower drive combination transistor in the high-voltage comparison circuit of the same level, and the other end is grounded; one end of the delayed closing contact of each time relay is connected to any non-repetitive disordered voltage input terminal, and the other end of the delayed closing contact is respectively connected to the diode anode of the high-voltage screening circuit of the corresponding next level.

8. The design method of the industrial-grade high-voltage monitoring automatic fool-proofing circuit according to claim 2 is characterized in that: The fool-proofing circuit is also provided with its own power supply circuit, which is supplied by an emitter follower. The emitter follower is composed of a voltage-stabilizing diode, a transistor and two resistors. The cathode of the voltage-stabilizing diode is respectively connected to one of the resistors and the base of the transistor, the anode of the voltage-stabilizing diode is grounded, and the cathode of the voltage-stabilizing diode is connected to the resistor and then connected to the highest voltage end of the output of the first-level high-voltage screening circuit; the emitter of the transistor is connected to another resistor and then grounded, and the emitter of the transistor is also connected to the output end, which is the positive electrode of the power supply of the overall circuit, and the collector of the transistor is connected to the highest voltage end of the output of the first-level high-voltage screening circuit.

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