A kind of fusion electrolytic hydrogen production and hydrogen fuel cell stack voltage patrol switch

Abstract

The utility model provides a kind of voltage patrol switch of fusion electrolytic hydrogen production and hydrogen fuel cell stack, comprising: stack, scanning relay group, polarity relay group, data collector, main control unit, first output bus, second output bus;The stack includes N batteries in series, the negative pole of N battery is connected with the left end of N lead, the positive pole of N battery is connected with the left end of N+1 lead;The scanning relay group includes N+1 channel switching relay;The polarity relay group includes first polarity switching relay and second polarity switching relay;The main control unit has N+1 selected channel signal pin, first selected polarity signal pin and second selected polarity signal pin, also has synchronous acquisition signal pin.The utility model switch scanning module can realize the automatic adjustment of the positive and negative polarity of single battery, provide the operation timing coordination function between switch action and data acquisition.

Description

Technical Field

[0001] This utility model relates to the fields of water electrolysis hydrogen production and hydrogen fuel cell technology, specifically to a voltage monitoring switch that integrates water electrolysis hydrogen production and hydrogen fuel cell stack. Background Technology

[0002] Hydrogen energy is a secondary energy source that is abundant, green, low-carbon, and widely applicable, serving as an important vehicle for achieving green and low-carbon transformation in energy consumption. my country's hydrogen energy industry is showing a positive development trend, and has initially mastered the main technologies and production processes for hydrogen production, storage and transportation, hydrogen refueling, fuel cells, and system integration.

[0003] The comprehensive performance of hydrogen electrolysis and hydrogen fuel cells can be characterized by their electrical performance. Voltage is the most direct reflection of the performance of the electrolyzer and the fuel cell stack. Therefore, conducting voltage testing of the electrical performance of hydrogen electrolysis and hydrogen fuel cells is of great significance. It will help achieve breakthroughs in the core technologies of hydrogen electrolysis and hydrogen fuel cells and accelerate the industrialization process of hydrogen electrolysis and hydrogen fuel cells.

[0004] The current problems in the evaluation of the electrical performance of fuel cell stacks are as follows: (1) There is no dedicated metrological standard. According to relevant standards, the performance evaluation equipment used for testing systems of fuel cell stacks (including hydrogen fuel cells and electrolytic hydrogen production) needs to be verified by the metrology department. In actual work, such as the fuel cell stack inspection device (CVM), it is integrated into the monitoring and control system of the fuel cell stack and cannot be disassembled and sent for inspection separately, which increases the difficulty of verification and reduces the reliability of verification. Moreover, there is currently no dedicated "metrological standard" on the market that can be directly used for the metrological verification of fuel cell stack inspection devices. Therefore, it is necessary to develop a targeted dedicated device to solve this problem. (2) The existing equipment indicators are not high enough. The technical requirements for fuel cell stack inspection devices are: voltage measurement error within ±5mV; while as a metrological standard, the indicators need to be two levels higher than the object being measured, reaching ±1mV, or ±0.1% (or even ±0.05% or higher). (3) There is a problem with the coordination between the switching action and data acquisition of existing inspection devices. There are two approaches to the inspection system: The first is to use a multi-channel synchronous data acquisition unit to record the voltage parameters of multiple individual cells in the fuel cell stack in real time. However, the number of synchronous channels in a multi-channel synchronous data acquisition unit is limited (i.e., the number of channels is still finite, with some on the market having around thirty channels). Expanding the number of acquisition units does not adequately adapt to fuel cell stacks of various sizes, and the equipment investment cost is higher, while the accuracy is lower. The second approach uses a high-precision single acquisition unit combined with a multi-channel scanning switch. By adding more multi-channel scanning switches, the number of acquisition channels can be expanded, which can better adapt to fuel cell stacks of various sizes. However, the second technical solution has a coordination problem between the "switching operation" and "data acquisition" steps, and this coordination problem urgently needs to be solved.

[0005] I. A Chinese utility model patent (CN201859204U) proposes a multi-channel switch simulation method. This patent uses two multi-channel simulation switches with a total of 32 channels, but only collects data from 15 individual cells, resulting in low utilization. Secondly, there will be potential accumulation when the midpoint of the 15 individual cells is connected to the COM common terminal. Furthermore, the AD bit depth used in this patent is low, so it can only be used for monitoring the fuel cell stack and cannot be used as a measurement standard.

[0006] II. Chinese Invention Patent (CN102288813B) proposes a single-cell voltage inspection system for fuel cell stacks capable of detecting positive and negative voltages. While it can measure both positive and negative signals, the method of grounding one end of the selected cell causes potential accumulation. Furthermore, the selection and switching process is complex and unsuitable for complex fuel cell stack systems. Chinese Utility Model Patent (CN212517270U) provides a single-cell inspection system for fuel cells. Its proposed isolation scheme can solve the problem of potential accumulation in the fuel cell stack, but it does not address the issue of contact potential in individual cells.

[0007] Third, Chinese invention patent (CN108761350B) proposes a fuel cell stack cell voltage monitoring system with start-stop equalization control. It sequentially selects each cell via an optocoupler gating circuit, and an odd-even conversion module corrects the positive and negative relationships of the voltage signal. However, this patent's cell voltage monitoring system lacks a synchronous trigger pulse output function and does not address how it coordinates with the data acquisition unit after the switch is selected. Since there is a transition time between switch selection and signal establishment, this transition time cannot be ignored for accurate acquisition of the cell's voltage. If data acquisition begins before signal establishment, the system will acquire transitional data, leading to unreliable or erroneous results.

[0008] In summary, there is an urgent need in this technical field for a voltage monitoring switch that integrates hydrogen electrolysis and hydrogen fuel cell stacks, which can overcome the shortcomings of the prior art described above. Utility Model Content

[0009] The technical problem to be solved by this utility model is to provide a voltage monitoring switch that integrates hydrogen electrolysis and hydrogen fuel cell stack.

[0010] The technical solution of this utility model is implemented as follows: a voltage monitoring switch integrating electrolytic hydrogen production and hydrogen fuel cell stack, comprising:

[0011] Battery stack, scanning relay group, polarity relay group, data acquisition unit, main controller, first output bus, second output bus;

[0012] The fuel cell stack includes N batteries connected in series. The negative terminals of the N batteries are connected to the left ends of the N leads respectively, and the positive terminal of the Nth battery is connected to the left end of the (N+1)th lead. N is an integer greater than two.

[0013] The scanning relay group includes N+1 channel switching relays. The right ends of the N leads are respectively connected to the stationary contacts of the N channel switching relays. The right end of the N+1th lead is connected to the stationary contact of the N+1th channel switching relay. Among the N+1 channel switching relays, the moving contacts of the odd-numbered channel switching relays are connected to the first output bus, and the moving contacts of the even-numbered channel switching relays are connected to the second output bus.

[0014] The polarity relay group includes a first polarity switching relay and a second polarity switching relay. The first stationary contact of the first polarity switching relay is connected to the first output bus, the second stationary contact of the first polarity switching relay is connected to the second output bus, and the moving contact of the first polarity switching relay is connected to the first acquisition terminal of the data acquisition device. The first stationary contact of the second polarity switching relay is connected to the first output bus, the second stationary contact of the second polarity switching relay is connected to the second output bus, and the moving contact of the second polarity switching relay is connected to the second acquisition terminal of the data acquisition device.

[0015] The main controller has N+1 channel selection signal pins, which are respectively connected to the coils of N+1 channel switching relays. The main controller also has a first polarity selection signal pin and a second polarity selection signal pin. The first polarity selection signal pin is connected to the coil of the first polarity switching relay, and the second polarity selection signal pin is connected to the coil of the second polarity switching relay. The main controller also has a synchronous acquisition signal pin, which is connected to the trigger terminal of the data acquisition unit.

[0016] Furthermore, it also includes: a relay driving module, wherein the N+1 channel selection signal pins are respectively connected to the coils of the N+1 channel switching relays through the N+1 relay driving module.

[0017] Furthermore, it also includes a status monitoring module, wherein the N+1 relay drive modules are respectively connected to the N+1 status monitoring modules.

[0018] Furthermore, it also includes: a synchronization pulse output module, wherein the synchronization acquisition signal pin is connected to the trigger terminal of the data acquisition device through the synchronization pulse output module.

[0019] Furthermore, it also includes: a first cascade port, a second cascade port, a communication module, and a host computer. The first cascade port and the second cascade port are respectively connected to the first cascade signal pin and the second cascade signal pin of the main controller. The host computer is connected to the main controller through the communication module.

[0020] The voltage inspection switches are multiple and cascaded to form a synchronous inspection switch array. The first cascade port of the voltage inspection switch in this stage is connected to the second cascade port of the voltage inspection switch in the previous stage, and the second cascade port of the voltage inspection switch in this stage is connected to the first cascade port of the voltage inspection switch in the next stage.

[0021] Furthermore, it also includes: a power module, a button module, and a display module, wherein the power module is connected to the power signal pin of the main controller, the button module is connected to the button signal pin of the main controller, and the display module is connected to the display signal pin of the main controller.

[0022] Furthermore, it also includes: a self-calibration module, which comprises N resistors connected in series, each resistor having a single-gain precision buffer connected in series at both ends, the N resistors connected in series with an external power supply, and the left end of the Nth lead being connected to the Nth single-gain precision buffer.

[0023] Compared with the prior art, the beneficial effects or advantages of this utility model are as follows:

[0024] (1) The data acquisition device used in the voltage inspection switch is a high-speed, high-precision digital sampling voltmeter (similar to a high-precision ADC converter). Actual testing has verified that when a sampling rate that meets the inspection speed requirements is used, its digital sampling relative error is better than ±0.01%, which is better than ±0.1% (±5mV) of the existing technology.

[0025] (2) The scanning relay group and the polarity relay group form a switch scanning module that can realize the automatic adjustment of the positive and negative polarities at both ends of a single battery cell. Existing technology can realize the automatic adjustment of the positive and negative polarities between individual cells. When used as a metrological standard for comparative measurement, the contact potential introduced by the switch and the connecting wires cannot be ignored. When measuring a single cell, the contact potential needs to be eliminated. Therefore, the switch must be able to realize the positive and negative measurement of a single battery cell.

[0026] (3) Provide operation timing coordination between switching action and data acquisition to ensure the accuracy and safety of stack voltage measurement.

[0027] (4) Add self-calibration module function to provide self-calibration function, which can provide periodic calibration, in-use inspection and correction functions for scanning system; combined with standard dynamic signal, verify the dynamic measurement capability of scanning system. Attached Figure Description

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0029] Figure 1 This is a structural block diagram of the 24-channel synchronous inspection switch unit in this utility model.

[0030] Figure 2 This is a structural block diagram of the 24-channel synchronous inspection switch array in this utility model.

[0031] Figure 3 This is a schematic diagram of the synchronous inspection switch in this utility model.

[0032] Figure 4 This is a schematic diagram of the self-calibration wiring of the synchronous inspection switch in this utility model.

[0033] Figure 5 This is a schematic diagram of the operation sequence of the synchronous inspection switch in this utility model.

[0034] Figure 6 This is a schematic diagram of the main controller in this utility model.

[0035] Figure 7 This is a structural schematic diagram of the power supply module in this utility model.

[0036] Figure 8 This is a structural schematic diagram of the communication module in this utility model.

[0037] Figure 9 This is a schematic diagram of the switch scanning module in this utility model.

[0038] Figure 10 This is a schematic diagram of the relay drive module in this utility model.

[0039] Figure 11 This is a structural schematic diagram of the status monitoring module in this utility model.

[0040] Figure 12 This is a schematic diagram of the synchronous pulse output module in this utility model. Detailed Implementation

[0041] Please see Figures 1 to 12 As shown, this is a preferred embodiment of the present invention.

[0042] A voltage monitoring switch integrating hydrogen electrolysis production and hydrogen fuel cell stack, comprising:

[0043] Battery stack, scanning relay group, polarity relay group, data acquisition unit, main controller, first output bus, second output bus;

[0044] The fuel cell stack includes N batteries connected in series. The negative terminals of the N batteries are connected to the left ends of the N leads respectively. The negative terminal of the Nth battery is connected to the left end of the Nth lead, and the positive terminal of the Nth battery is connected to the left end of the (N+1)th lead. N is an integer greater than two.

[0045] The scanning relay group includes N+1 channel switching relays. The right ends of the N leads are respectively connected to the stationary contacts of the N channel switching relays. The right end of the Nth lead is connected to the stationary contact of the Nth channel switching relay, and the right end of the N+1th lead is connected to the stationary contact of the N+1th channel switching relay. Among the N+1 channel switching relays, the moving contacts of the odd-numbered channel switching relays are connected to the first output bus, and the moving contacts of the even-numbered channel switching relays are connected to the second output bus.

[0046] The polarity relay group includes a first polarity switching relay and a second polarity switching relay. The first stationary contact of the first polarity switching relay is connected to the first output bus, the second stationary contact of the first polarity switching relay is connected to the second output bus, and the moving contact of the first polarity switching relay is connected to the first acquisition terminal of the data acquisition device. The first stationary contact of the second polarity switching relay is connected to the first output bus, the second stationary contact of the second polarity switching relay is connected to the second output bus, and the moving contact of the second polarity switching relay is connected to the second acquisition terminal of the data acquisition device.

[0047] The main controller has N+1 channel selection signal pins, which are respectively connected to the coils of N+1 channel switching relays. The N+1th channel selection signal pin is connected to the coil of the N+1th channel switching relay. The main controller also has a first polarity selection signal pin and a second polarity selection signal pin. The first polarity selection signal pin is connected to the coil of the first polarity switching relay, and the second polarity selection signal pin is connected to the coil of the second polarity switching relay. The main controller also has a synchronous acquisition signal pin, which is connected to the trigger terminal of the data acquisition unit.

[0048] In this invention, the main controller sends a channel selection signal to the scanning relay group, causing adjacent channel switching relays to sequentially turn on and off for inspection. The main controller also sends a polarity selection signal to the polarity relay group, causing the first polarity switching relay and the second polarity switching relay to reverse polarity each time. This ensures that the first acquisition terminal of the data acquisition unit is connected to the positive terminal of a single battery, and the second acquisition terminal is connected to the negative terminal of a single battery, sequentially selecting batteries in the stack for voltage detection. After a specified delay time (the delay time after the relay switching is complete) is elapsed after selecting a battery via the channel switching relay, the main controller sends a signal to trigger the data acquisition unit to begin data acquisition. This ensures that data acquisition and detection are performed when the contacts of the channel switching relay are stably closed, improving the accuracy of voltage detection.

[0049] The synchronous inspection switch consists of a scanning relay group, a polarity relay group, a main controller, a first output bus, and a second output bus. Combined with... Figure 3 N batteries connected in series are C1 to Cn; N+1 channel switching relays are S1 to Sn+1; the first polarity switching relay is K1; the second polarity switching relay is K2; the first output bus is P1; the second output bus is P2; the first acquisition terminal of the data acquisition unit is H; the second acquisition terminal of the data acquisition unit is L.

[0050] For example, the fuel cell stack includes twenty-four cells connected in series. The negative terminal of the first cell is connected to the left end of the first lead, the negative terminal of the twenty-fourth cell is connected to the left end of the twenty-fourth lead, and the positive terminal of the twenty-fourth cell is connected to the left end of the twenty-fifth lead. There are twenty-five channel switching relays. The moving contacts of the odd-numbered channel switching relays (first, third, fifth to twenty-fifth) are connected to the first output bus, and the moving contacts of the even-numbered channel switching relays (second, fourth, sixth to twenty-fourth) are connected to the second output bus. The main controller has twenty-five channel selection signal pins. When the first and second channel switching relays select the first battery, the first polarity switching relay selects the first output bus, and the second polarity switching relay selects the second output bus. When the second and third channel switching relays select the second battery, the first polarity switching relay selects the second output bus, and the second polarity switching relay selects the first output bus. When the third and fourth channel switching relays select the third battery, the first polarity switching relay selects the first output bus, and the second polarity switching relay selects the second output bus. When the fourth and fifth channel switching relays select the fourth battery, the first polarity switching relay selects the second output bus, and the second polarity switching relay selects the first output bus. This process continues until the inspection and polarity reversal are completed.

[0051] Furthermore, combined Figure 1 , Figure 1This is a structural block diagram of the 24-channel synchronous inspection switch unit of this utility model. It also includes: a relay drive module, wherein the N+1 channel selection signal pins are respectively connected to the coils of the N+1 channel switching relays through the N+1 relay drive module. The N+1th channel selection signal pin is connected to the coil of the N+1th channel switching relay through the N+1th relay drive module.

[0052] As can be seen from this description, setting the relay drive module to provide sufficient electrical signals enables the channel switching relay to perform switching actions more stably.

[0053] Furthermore, combined with Figure 1 It also includes a status monitoring module, wherein the N+1 relay drive modules are each connected to the N+1 status monitoring modules. The N+1th relay drive module is also connected to the N+1th status monitoring module.

[0054] As can be seen from this description, the status monitoring module can provide a clearer understanding of whether the corresponding channel switching relay is in the on or off state.

[0055] Furthermore, combined with Figure 1 It also includes: a synchronization pulse output module, wherein the synchronization acquisition signal pin is connected to the trigger terminal of the data acquisition device through the synchronization pulse output module.

[0056] As can be seen from this description, the synchronization pulse output module is used to enhance the synchronization acquisition signal sent by the main controller, which helps to stably trigger the acquisition work of the data acquisition unit.

[0057] Furthermore, combined with Figure 1 It also includes: a first cascade port, a second cascade port, a communication module, and a host computer. The first cascade port and the second cascade port are respectively connected to the first cascade signal pin and the second cascade signal pin of the main controller. The host computer is connected to the main controller through the communication module.

[0058] Combination Figure 2 , Figure 2 This is a structural block diagram of the 24-channel synchronous inspection switch array of this utility model. Multiple voltage inspection switches are cascaded to form a synchronous inspection switch array. The first cascade port of the voltage inspection switch in this stage is connected to the second cascade port of the voltage inspection switch in the previous stage, and the second cascade port of the voltage inspection switch in this stage is connected to the first cascade port of the voltage inspection switch in the next stage.

[0059] The first cascade port is Figure 1 and Figure 2 The first cascade port is Ⅰ; the second cascade port is Ⅰ. Figure 1 and Figure 2Cascading port II in the middle.

[0060] As described above, the voltage monitoring switch of this invention has a cascading function. Multiple voltage monitoring switches can be cascaded sequentially to monitor more battery stacks connected in series. The host computer controls the orderly operation of each voltage monitoring switch via a communication module.

[0061] Furthermore, combined Figure 1 It also includes: a power module, a button module, and a display module. The power module is connected to the power signal pin of the main controller, the button module is connected to the button signal pin of the main controller, and the display module is connected to the display signal pin of the main controller.

[0062] From this description, we can see that the power module provides power, the button module is used to input setting parameters to the main controller, and the display module is used by the main controller to output the operating results, so that the staff can understand the current status of the voltage inspection switch.

[0063] Furthermore, combined Figure 4 , Figure 4 This is a schematic diagram of the self-calibration wiring of the synchronous inspection switch in this utility model. It also includes a self-calibration module, which comprises N resistors connected in series. Each resistor has a single-gain precision buffer connected in series across its two ends. The N resistors are connected to an external power supply, and the left end of the Nth lead is connected to the Nth single-gain precision buffer.

[0064] As can be seen from this description, the self-calibration module simulates the fuel cell stack and is used to calibrate the operating status of the voltage monitoring switch, which helps to debug the voltage monitoring switch and improves the accuracy of subsequent actual fuel cell stack testing.

[0065] The N batteries connected in series are respectively Figure 4 V1 to Vn; N single-gain precision buffers are respectively Figure 4 U1 to Un in the series.

[0066] To better understand the above technical solution, a detailed explanation is provided below.

[0067] This utility model aims to provide a voltage inspection switch that integrates electrolytic hydrogen production and hydrogen fuel cell stacks, used to construct a measurement standard device to solve the following problems in the prior art: (1) There is currently no dedicated measurement standard for evaluating the electrical performance of fuel cell stacks, and the accuracy is not high enough. (2) Since the voltage amplitude of each cell is not high, when used as a measurement standard for comparison measurement, the contact potential introduced between the switch and the connecting line cannot be ignored. When measuring a single cell, the contact potential needs to be eliminated. Therefore, the switch must be able to achieve positive and negative measurement of a single cell. (3) Due to the uncertainty of the field environment, a self-calibration module is provided to verify the measurement capability of the scanning system under different fuel cell stack operating conditions. (4) There is a transition time when the signal is established after the switch is turned on. To correctly collect the voltage at both ends of a single cell, the voltage inspection system needs to have a synchronous trigger pulse output function to complete the timing coordination between the switch scanning unit and the data acquisition system.

[0068] This utility model's voltage monitoring switch can be used for voltage monitoring of individual cells (hereinafter referred to as "single cells") in various types of fuel cell stacks (such as fuel cell stacks, water electrolysis hydrogen production electrolyzer stacks, or battery modules). The voltage monitoring switch is modularly designed as a synchronous monitoring switch unit, with each unit capable of scanning twenty-four single cells, such as... Figure 1 The diagram shows the structure of the 24-channel synchronous inspection switch unit of this invention. It consists of a main controller, power supply module, communication module, switch scanning module, relay drive and status monitoring module, synchronous pulse output module, self-calibration module, and peripheral modules (buttons, display). This patent employs a high-speed, high-precision digital sampling voltmeter (similar to a high-precision ADC converter). The number of scanning channels is expanded by cascading units to accommodate different sizes of fuel cells, theoretically allowing for unlimited expansion. Figure 2 As shown.

[0069] Voltage monitoring switches have the following three characteristics:

[0070] (1) Switch scanning module (S1, S2...S25; ​​K1, K2)

[0071] The switch scanning module consists of twenty-five channel switching relays and two polarity switching relays. The twenty-five channel switching relays are used for channel switching of twenty-four individual cells. Each individual cell is connected to two channel switching relays. The channel switching relays are connected sequentially to the first output bus P1 and the second output bus P2 according to the order of the individual cells they are connected to. The two polarity switching relays are used for polarity reversal (e.g., ...). Figure 3 By designing a two-stage switch structure, the number of measurement leads can be reduced from 2n to n+1, while the polarity of the switch scanning module can be adjusted between channels and within the channel itself.

[0072] The main controller sends commands based on the operating conditions. These commands are controlled by two control codes: one for "channel selection" and the other for "polarity selection." During channel-by-channel inspection, the polarity of the first output bus P1 alternates between positive and negative, while the polarity of the second output bus P2 alternates between negative and positive. The polarity of the first and second output buses P1 and P2 can be changed using the first polarity switching relay K1 and the second polarity switching relay K2, ensuring that the final output polarity of the buses remains constant. On the other hand, the voltage amplitude of a single cell is generally low. In this case, the combined parasitic potential introduced by temperature changes in the connections between components such as measuring leads, relays, and measuring instruments cannot be ignored. The contact thermoelectric potential is measured using the "polarity reversal method," and the measurement results are corrected to eliminate the cumulative contact potential caused by multiple single-cell series connections.

[0073] (2) Self-calibration module

[0074] The self-calibration module consists of twenty-four precision alloy foil resistors of identical value, forming a twenty-four-way "1:1...:1" resistor voltage divider network. Each resistor is connected in series with a single-gain precision buffer, so the differential voltage Vi (i = 1, 2, ... 24) across each resistor equals the input voltage Ui (i = 1, 2, ... 24) of the switching scanning module. This simulates the twenty-four single-cell voltages (which can be considered standard voltages here) and transforms the output impedance of the voltage divider network, thus isolating the measurement circuit from the load side. Combined with... Figure 4 The self-calibration module can be connected to an existing programmable signal source as a calibration signal input to simulate single-cell voltage signals with various changing characteristics, which is used to verify the measurement capability of the scanning measurement system under different fuel cell stack operating conditions.

[0075] (3) Synchronous signal output module

[0076] This patent employs a high-precision single data acquisition unit combined with a multi-channel switch scanning structure. By increasing the number of acquisition channels through multi-channel switch scanning, it can better adapt to fuel cell stacks of various sizes. However, when conducting single-cell voltage inspection of a fuel cell stack using a multi-channel switch, a detail that is easily overlooked is the operational coordination between the channel switch and the connected data acquisition unit. A handshake mechanism should be established between the two. The transition time from receiving a closing command to the switch being fully closed is defined as the "signal setup time." After the signal setup time delay, the switch generates a synchronization pulse output signal as the trigger signal for the data acquisition unit to start sampling. In addition, to ensure the safety of scanning measurements, only one cell is allowed to be connected at any time, following the "disconnect before connect" principle. After completing acquisition and reading, the data acquisition unit also provides a "measurement complete" status indicator, notifying the switch to perform a disconnect operation.

[0077] like Figure 5 As shown, Figure 5 This is a schematic diagram of the synchronous inspection switch operation timing in this utility model. When the host computer sends a switch closing command, due to the relay's switching time, there is a delay t1 between the switch being turned on and the output TTL pulse. When using a timed sampling mode, the first sampling will occur after a trigger delay time after triggering. After the first sampling begins, the second sampling begins after the sampling time interval, and so on. There is a trigger delay t2 between the rising edge (or falling edge, depending on the polarity setting of the trigger edge) of the TTL pulse and the first sampling. Each channel's n samples are taken at equal time intervals, and the total sampling time should be included within the on-time of each channel. t1 is the relay's action time. To ensure that each sampling is performed only for one channel, the next channel can only be sampled after the previous channel is disconnected. Therefore, the relay's action time should be considered as 2t1, approximately 8ms. The trigger delay time t2 is related to the set integration time. When the set integration time is 20ms (equivalent to NPLC=1), the trigger delay is 160μs. If the number of channel samples is n, the time to complete sampling for one channel is n times the integration period. To successfully complete independent sampling of each channel, the operating timing of each component should be fully analyzed. The sampling process of each channel should be included within the "on time" of the switch and the "time interval" of sampling, and the characteristics of the signal being measured should also be considered.

[0078] This patent has the following four improvements compared to existing technologies:

[0079] (1) The data acquisition device used in the voltage inspection switch is a high-speed, high-precision digital sampling voltmeter (similar to a high-precision ADC converter). Actual testing has verified that when a sampling rate that meets the inspection speed requirements is used, its digital sampling relative error is better than ±0.01%, which is better than ±0.1% (±5mV) of the existing technology.

[0080] (2) The scanning relay group and the polarity relay group form a switch scanning module that can realize the automatic adjustment of the positive and negative polarities at both ends of a single battery cell. Existing technology can realize the automatic adjustment of the positive and negative polarities between individual cells. When used as a metrological standard for comparative measurement, the contact potential introduced by the switch and the connecting wires cannot be ignored. When measuring a single cell, the contact potential needs to be eliminated. Therefore, the switch must be able to realize the positive and negative measurement of a single battery cell.

[0081] (3) Provide operation timing coordination between switching action and data acquisition to ensure the accuracy and safety of stack voltage measurement.

[0082] (4) Add self-calibration module function to provide self-calibration function, which can provide periodic calibration, in-use inspection and correction functions for scanning system; combined with standard dynamic signal, verify the dynamic measurement capability of scanning system.

[0083] This utility model's voltage monitoring switch can be used for voltage monitoring of various types of fuel cell stacks (such as fuel cell stacks, water electrolysis hydrogen production cell stacks, or individual cells in battery modules, hereinafter referred to as "single cells"). The voltage monitoring switch is modularly designed as a synchronous monitoring switch unit, and each unit can scan twenty-four single cells; such as Figure 1 As shown, it consists of a main controller, power supply module, communication module, switch scanning module, relay driver and status monitoring module, synchronous pulse output module, self-calibration module and peripheral modules (buttons, display).

[0084] Combination Figure 6 Main controller: The main controller (MCU) adopts STM32F103RBT6, based on the ARM Cortex-M3 core, with a maximum operating frequency of 72MHz, providing a processing capability of 90DMIPS (millions of instructions per second), supporting single-cycle multiplication and hardware division operations, adopting a 32-bit RISC architecture, with a streamlined and efficient instruction set, suitable for real-time control and complex algorithm processing.

[0085] Combination Figure 7 Power Module: Input power voltage conversion circuit, converting (9-24)V to 5V, and also supports USB input, used to provide operating power and control voltage for microcontrollers and relays. The power module also includes a TPS5430 power conversion chip, using a fixed frequency (500kHz) control mode, supporting high-precision output adjustment. Input voltage range: 5.5V to 36V, output voltage adjustable range 1.221V to 32V, accuracy up to ±1.5%, conversion efficiency up to 95%, continuous output current up to 3A, meeting high load requirements, and responsible for powering the relay drive module.

[0086] Combination Figure 8Communication Module: Communication between the voltage monitoring switch and the host computer is implemented via serial port, using the FT232R serial port converter chip. The FT232R, through its built-in USB protocol engine and UART controller, converts the USB interface into a standard RS-232 / RS-422 / RS-485 serial communication interface, enabling interaction between the PC and the serial device (switch scanning module). The FT232R supports asynchronous communication mode (character transmission) and synchronous FIFO mode (high-speed data block transmission), is compatible with RS-232, RS-422, and RS-485 serial protocols, supports baud rates up to 3Mbps, and can be directly connected to the host controller's UART pin (0V / 3.3V or 5V logic) to generate TTL level. In the switch scanning module, the USB1 port is responsible for communication between the host computer and the switch scanning module. The communication section of the switch scanning module also includes cascading between different modules. Through two USB-TYPE-C interface terminals, the USB2 port of the latter module is connected to the USB3 port of the former module to provide communication and power supply between the microcontroller of the cascaded module and the host computer.

[0087] Combination Figure 9 Switch scanning module: The switch scanning module consists of two parts, input and output, both using TX2-5V electromagnetic relays. The input part uses twenty-five relays to form a scanning relay group, and the output part uses two relays to form a polarity relay group. The TX2-5V operates based on the principle of electromagnetic induction. By energizing the coil, a magnetic field is generated, which attracts the armature and drives the contacts to close or open, thereby realizing the on / off control of the circuit.

[0088] Combination Figure 10 and Figure 11 Relay drive and status monitoring module: The scanning relay group uses three ULN2803A chips for relay drive and status monitoring, with relay status indicated by LEDs. The polarity reversal relay group uses two ULN2001D chips, with inputs directly connected to the MCU's GPIO pins. Because the chips have built-in 2.7kΩ base resistors and 4.7kΩ pull-down resistors, they can be directly connected to TTL / CMOS logic circuits. The collector output of each Darlington transistor (e.g., 1C, 2C, 3C) is connected to one end of the relay coil, and the other end of the coil is connected to the load power supply. The open-collector output characteristic of the ULN2001D allows it to directly drive the relay coil to turn on and off; relay status is also indicated by LEDs.

[0089] Combination Figure 12 Synchronous pulse output module: Model TLP521 is a controllable optocoupler that achieves electrical isolation between the input and output terminals through the coupling of gallium arsenide infrared light-emitting diodes (LEDs) and phototransistors, and simultaneously completes the conversion of electrical signals to optical signals and back to electrical signals.

[0090] Self-calibration module: The self-calibration module consists of twenty-four precision alloy foil resistors with the same resistance value forming a twenty-four-way "1:1....:1" resistor voltage divider network. Each resistor is connected in series with a single-gain precision buffer at both ends to provide self-calibration function, providing periodic calibration, in-use inspection and correction functions for the scanning system; combined with standard dynamic signals, it verifies the dynamic measurement capability of the scanning system.

[0091] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A voltage monitoring switch integrating electrolytic hydrogen production and hydrogen fuel cell stack, characterized in that, include: Battery stack, scanning relay group, polarity relay group, data acquisition unit, main controller, first output bus, second output bus; The fuel cell stack includes N batteries connected in series. The negative terminals of the N batteries are connected to the left ends of the N leads respectively, and the positive terminal of the Nth battery is connected to the left end of the (N+1)th lead. N is an integer greater than two. The scanning relay group includes N+1 channel switching relays. The right ends of the N leads are respectively connected to the stationary contacts of the N channel switching relays. The right end of the N+1th lead is connected to the stationary contact of the N+1th channel switching relay. Among the N+1 channel switching relays, the moving contacts of the odd-numbered channel switching relays are connected to the first output bus, and the moving contacts of the even-numbered channel switching relays are connected to the second output bus. The polarity relay group includes a first polarity switching relay and a second polarity switching relay. The first stationary contact of the first polarity switching relay is connected to the first output bus, the second stationary contact of the first polarity switching relay is connected to the second output bus, and the moving contact of the first polarity switching relay is connected to the first acquisition terminal of the data acquisition device. The first stationary contact of the second polarity switching relay is connected to the first output bus, the second stationary contact of the second polarity switching relay is connected to the second output bus, and the moving contact of the second polarity switching relay is connected to the second acquisition terminal of the data acquisition device. The main controller has N+1 channel selection signal pins, which are respectively connected to the coils of N+1 channel switching relays. The main controller also has a first polarity selection signal pin and a second polarity selection signal pin. The first polarity selection signal pin is connected to the coil of the first polarity switching relay, and the second polarity selection signal pin is connected to the coil of the second polarity switching relay. The main controller also has a synchronous acquisition signal pin, which is connected to the trigger terminal of the data acquisition unit.

2. The voltage monitoring switch for integrating electrolytic hydrogen production and hydrogen fuel cell stack according to claim 1, characterized in that, Also includes: The relay drive module connects the N+1 channel selection signal pins to the coils of the N+1 channel switching relays via the N+1 relay drive module.

3. The voltage monitoring switch for integrating electrolytic hydrogen production and hydrogen fuel cell stack according to claim 2, characterized in that, It also includes a status monitoring module, wherein the N+1 relay drive modules are each connected to the N+1 status monitoring module.

4. The voltage monitoring switch for integrating electrolytic hydrogen production and hydrogen fuel cell stack according to claim 1, characterized in that, Also includes: A synchronous pulse output module is provided, wherein the synchronous acquisition signal pin is connected to the trigger terminal of the data acquisition device through the synchronous pulse output module.

5. A voltage monitoring switch for integrating electrolytic hydrogen production and hydrogen fuel cell stacks according to claim 1, characterized in that, Also includes: The system comprises a first cascade port, a second cascade port, a communication module, and a host computer. The first cascade port and the second cascade port are respectively connected to the first cascade signal pin and the second cascade signal pin of the main controller. The host computer is connected to the main controller through the communication module. The voltage inspection switches are multiple and cascaded to form a synchronous inspection switch array. The first cascade port of the voltage inspection switch in this stage is connected to the second cascade port of the voltage inspection switch in the previous stage, and the second cascade port of the voltage inspection switch in this stage is connected to the first cascade port of the voltage inspection switch in the next stage.

6. The voltage monitoring switch for integrating electrolytic hydrogen production and hydrogen fuel cell stack according to claim 1, characterized in that, Also includes: The system includes a power module, a button module, and a display module. The power module is connected to the power signal pin of the main controller, the button module is connected to the button signal pin of the main controller, and the display module is connected to the display signal pin of the main controller.

7. A voltage monitoring switch for integrating electrolytic hydrogen production and hydrogen fuel cell stacks according to claim 1, characterized in that, Also includes: The self-calibration module includes N resistors connected in series, with a single-gain precision buffer connected in series across both ends of each resistor. The N resistors are connected to an external power supply, and the left end of the Nth lead is connected to the Nth single-gain precision buffer.

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