Control method and system of hydrogen production power supply based on mcsc topology structure

Abstract

This invention discloses a control method and system for a hydrogen production power supply based on an MCSC topology, belonging to the field of new energy hydrogen production technology. The method includes: acquiring the real-time phase angle of the grid voltage as a synchronization reference for the control loop; switching between DC voltage control mode and DC current control mode according to the electrolyzer operating conditions; generating an active current setpoint based on voltage error and monitoring current over-limit in voltage mode, and generating an active current setpoint based on current error and monitoring voltage over-limit in current mode; generating a reactive current setpoint based on reactive power error; converting the active and reactive current setpoints into instantaneous current setpoints, and combining them with the phase angle to generate a drive pulse to control the operation of each power module. This invention achieves safe and efficient operation of the hydrogen production power supply across the entire operating range through dual-mode adaptive switching and cross-limiting protection.

Description

Technical Field

[0001] This invention relates to the field of new energy hydrogen production technology, specifically to a control method and system for a hydrogen production power supply based on MCSC topology. Background Technology

[0002] Hydrogen energy, as a zero-emission clean energy source, occupies an important position in the new energy system. With the increase in hydrogen production scale, electrolyzers are developing towards higher power and higher current, which places higher demands on the output capacity and control performance of hydrogen production power supplies.

[0003] Traditional hydrogen production power supplies often employ a multi-stage conversion topology that cascades a voltage source converter and a DC-DC converter, achieving voltage regulation through the coordination of the front-end rectification and the subsequent DC-DC conversion. This topology suffers from problems such as complex structure, numerous conversion stages, low system efficiency, and slow control response, making it difficult to meet the stability and accuracy requirements of high-power hydrogen production. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides a control method and system for a hydrogen production power supply based on an MCSC topology. The method employs a single-stage MCSC (Modular Parallel Current Source Converter) topology to directly convert AC input into DC power required by the electrolyzer, thereby improving system efficiency and control performance.

[0005] This invention is achieved through the following technical solution: In a first aspect, this application provides a control method for a hydrogen production power source based on an MCSC topology, comprising the following steps: During the operation of the hydrogen production power source, the real-time phase angle of the grid voltage is continuously acquired as a synchronization reference for the hydrogen production power source control loop. The current control mode is determined based on the operating conditions of the electrolyzer: In DC voltage control mode, an active current setpoint is generated based on the error between the DC voltage command value and the actual DC voltage value. When the output DC current exceeds the maximum allowable DC current value, the active current setpoint is limited to the limit corresponding to the maximum allowable DC current value. In DC current control mode, the active current setpoint is generated based on the error between the DC current command value and the actual DC current value. When the output DC voltage exceeds the maximum allowable DC voltage value, the active current setpoint is limited to the limit corresponding to the maximum allowable DC voltage value.

[0006] The reactive current setpoint is generated based on the error between the reactive power command value and the actual reactive power value on the AC side of the hydrogen production power source. The active current setpoint and reactive current setpoint are converted into instantaneous current setpoints, and modulated in combination with the real-time phase angle of the grid voltage to generate drive pulses for each parallel power module, thereby controlling the operating state of each power module.

[0007] Preferably, determining the current control mode based on the operating conditions of the electrolyzer includes: When the temperature of the electrolytic cell is lower than the preset temperature threshold, it enters DC voltage control mode; When the temperature of the electrolytic cell reaches or exceeds the preset temperature threshold, it enters the DC current control mode.

[0008] Preferably, during the switching process between the DC voltage control mode and the DC current control mode, the command value after the switch is first subjected to ramp processing, so that the command value smoothly transitions from the current value to the target value at a preset ramp rate.

[0009] Preferably, the step of converting the active current setpoint and the reactive current setpoint into an instantaneous current setpoint includes: Using the active current setpoint as the d-axis component and the reactive current setpoint as the q-axis component, and combining the real-time phase angle of the grid voltage, the current setpoint in the two-phase rotating coordinate system is converted into the instantaneous current setpoint in the two-phase stationary coordinate system through inverse Park transformation.

[0010] Preferably, the step of modulating the real-time phase angle of the grid voltage to generate drive pulses for each parallel power module includes: The phase offset of the carrier signal of each power module is determined according to the number of parallel power modules, so that the carrier signals of each power module are uniformly staggered in phase; the instantaneous current setpoint is compared with the carrier signal of the corresponding phase of each power module to generate the driving pulse of each power module.

[0011] Preferably, the determination of the active current setpoint includes: A proportional-integral controller is used to perform closed-loop control on the error signal between the DC voltage command value and the actual DC voltage value, or the error signal between the DC current command value and the actual DC current value.

[0012] Preferably, the determination of the reactive current setpoint includes: A proportional-integral controller is used to perform closed-loop control on the error signal between the reactive power command value and the actual reactive power value; the output of the proportional-integral controller is all subjected to amplitude limiting processing to obtain the corresponding current setpoint value.

[0013] Preferred options also include: When a parallel power module fails, the failed power module is disconnected from the parallel system. The carrier phase shift angle of each power module is recalculated based on the number of remaining normal power modules. New drive pulses are generated according to the recalculated carrier phase shift angles to control the remaining normal power modules to continue operating.

[0014] Preferably, when the hydrogen production power source is started, multiple parallel power modules are controlled to be put into operation one by one at preset intervals; when the hydrogen production power source is shut down, multiple parallel power modules are controlled to be shut down simultaneously.

[0015] Secondly, this application provides a control method for a hydrogen production power source based on an MCSC topology, including: The phase-locked loop control module is used to continuously acquire the real-time phase angle of the grid voltage during the operation of the hydrogen production power supply, as a synchronization reference for the hydrogen production power supply control loop. The mode switching module is used to determine the current control mode according to the operating conditions of the electrolyzer and switch between DC voltage control mode and DC current control mode. The DC voltage control module is used to generate an active current setpoint based on the error between the DC voltage command value and the actual DC voltage value in DC voltage control mode, and to limit the active current setpoint to the limit corresponding to the maximum allowable DC current value when the output DC current exceeds the maximum allowable DC current value. The DC current control module is used to generate an active current setpoint based on the error between the DC current command value and the actual DC current value in DC current control mode, and to limit the active current setpoint to the limit corresponding to the maximum allowable DC voltage value when the output DC voltage exceeds the maximum allowable DC voltage value. The reactive power control module is used to generate a reactive current setpoint based on the error between the reactive power command value and the actual reactive power value on the AC side of the hydrogen production power source. The coordinate transformation and modulation module is used to convert the active current setpoint and the reactive current setpoint into instantaneous current setpoints, and modulate them in combination with the real-time phase angle of the grid voltage to generate drive pulses for each parallel power module, so as to control the working state of each power module.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: This application provides a control method for a hydrogen production power supply based on an MCSC topology. The method switches between two control modes depending on the electrolyzer's operating conditions: a DC voltage control mode is used during cold start-up, generating an active current setpoint with the goal of stabilizing the output voltage to ensure safe start-up of the electrolyzer; after stable operation, it switches to a DC current control mode, achieving high-power, high-efficiency hydrogen production with the goal of stabilizing the output current. Both modes have independent cross-limiting protection mechanisms: in voltage mode, current over-limits are monitored, and in current mode, voltage over-limits are monitored. If another parameter not directly controlled in either mode exceeds a safety threshold, the active current setpoint is forcibly clamped. Simultaneously, a reactive power control loop operates independently, compensating for the power factor at the grid connection point by adjusting the reactive current. The advantages of this method are as follows: First, it adapts to the significant differences in the cold and hot load characteristics of the electrolyzer through dual-mode adaptive switching, avoiding the limitations of a single control mode operating under all conditions; Second, the cross-limiting protection mechanism uses the active current setpoint as a unified limiting object, achieving bidirectional safe control of the DC-side output voltage and current without adding additional execution links; Third, the active and reactive power control channels operate independently and in parallel, ensuring precise adjustment of hydrogen production power while also taking into account the reactive power compensation needs of the power grid.

[0017] This application also proposes a control system, an electronic device, and a computer storage medium for a hydrogen production power source based on an MCSC topology, which possess all the advantages of the aforementioned control method for a hydrogen production power source based on an MCSC topology. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is an overall framework diagram of the MCSC hydrogen production power control system of the present invention; Figure 2 This invention provides the functional configuration for the control and protection system. Figure 3 This is a diagram illustrating the overall control function framework of the present invention. Figure 4 This is a control sequence diagram for starting and stopping the machine according to the present invention; Figure 5 This is the phase-locked loop control logic diagram of the present invention; Figure 6 This is a flowchart of the DC voltage and DC current command processing of the present invention; Figure 7This is the DC voltage and DC current control logic diagram of the present invention; Figure 8 This is the reactive power control logic diagram of the present invention; Figure 9 The current waveform output by the RTDS model of the hydrogen production power supply of this invention is shown. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0022] The control system for a hydrogen production power supply based on an MCSC topology provided in this application includes an AC power grid, an AC transformer, multiple parallel insulated-gate bipolar transistor (IGBT) power module converters, and an electrolyzer. The AC power grid, after being converted by the AC transformer, directly connects to multiple parallel IGBT power module converters on the low-voltage side of the AC transformer. The positive and negative terminals of each power module converter are connected in parallel to the two ends of the electrolyzer for hydrogen production via electrolysis.

[0023] See Figure 1 The control and protection system consists of a hydrogen production power supply control and protection cabinet, an Ethernet switch, local monitoring, and a station monitoring system. Start-up and shutdown control can be performed via start / stop buttons on the control and protection cabinet, or remotely via local or remote monitoring systems. The control and protection system collects the three-phase AC voltage and current on the high-voltage side of the AC transformer, the three-phase AC voltage on the low-voltage side, the total DC voltage and current at the electrolyzer terminals, and the positive and negative currents and module status information of each power module.

[0024] Reference Figure 2 The control and protection system implements functions such as phase-locked loop control, outer-loop control, system protection, and start / stop control in the main control central processing unit. Current carrier phase-shift modulation, fast module fault protection, and central processing unit fault detection are implemented in the main control field-programmable gate array. Simultaneously, control commands are distributed to multiple power module converters and power module status information is acquired via fiber optic distribution boards, and external communication connections are established with the water cooling system and monitoring system.

[0025] Reference Figure 3 The core control functions of the control and protection system include start-up and shutdown control, constant DC voltage control, constant DC current control, reactive power control, current carrier phase-shift modulation, fault ride-through control, and power module status monitoring. In practical applications, when hydrogen production begins, the electrolyzer temperature is low and the resistance is high. The system is initially set to constant DC voltage control mode for low-power electrolysis. After the electrolyzer temperature rises, it switches to constant DC current control mode to increase the DC current for high-power electrolysis.

[0026] The control method of the control system for the hydrogen production power source based on the MCSC topology is described below.

[0027] A control method for a hydrogen production power supply based on an MCSC topology is disclosed. This method is applicable to hydrogen production power supplies with a modular parallel current source converter topology. Through constant voltage / constant current dual-mode adaptive control and multi-module carrier phase-shift coordinated control, smooth regulation of the electrolysis hydrogen production process under all operating conditions is achieved. The method includes the following steps: Step 1: Based on the operating status command of the hydrogen production power supply, control the activation or deactivation of multiple parallel power modules to complete the smooth transition of the hydrogen production power supply from the shutdown state to the unlocked operating state, or from the unlocked operating state to the shutdown state.

[0028] 1) Startup Control: Upon receiving a start command, the system controls multiple power modules to not immediately engage simultaneously, but instead perform the closing operation one by one at preset intervals. After each power module is closed, the system waits for a preset interval before triggering the closing of the next power module, until all power modules have completed closing and entered the unlocked operation state.

[0029] 2) Shutdown Control: Upon receiving a shutdown command, all power modules are simultaneously tripped, bringing all power modules out of operation at once and restoring the system to a shutdown state. (Refer to...) Figure 4 .

[0030] By adopting a sequential activation strategy, the current surge and voltage fluctuations caused by the simultaneous activation of multiple power modules are avoided, reducing the stress on the power grid and equipment and ensuring the smoothness of the start-up and shutdown process.

[0031] In some embodiments, the power module activation interval can be dynamically adjusted according to the fluctuation of DC bus voltage or AC grid voltage. When the voltage fluctuation is small, the interval is shortened to speed up the start-up, and when the voltage fluctuation is large, the interval is extended to ensure stability.

[0032] In some embodiments, start-stop control can be manually operated via the start-stop button on the control protection cabinet, or remotely operated via a local monitoring system or a remote monitoring system.

[0033] Step 2: During the operation of the hydrogen production power source, based on the collected three-phase AC voltage signal on the high-voltage side of the AC transformer, phase-locked loop control is continuously performed to obtain the real-time voltage phase angle of the power grid.

[0034] It should be noted that the phase-locked loop control operates continuously throughout the entire process of hydrogen power generation, including startup, normal operation, and shutdown. During the startup process in step 1, control calculations are performed based on this phase angle for each power module that is put into operation.

[0035] See Figure 5 The specific method is as follows: S2.1 Acquire the three-phase AC voltage signal from the high-voltage side of the AC transformer, and obtain a voltage signal with the same angle as the low-voltage side voltage after angle conversion.

[0036] S2.2 Perform Park transformation on the voltage signal after angle conversion to obtain the voltage components in the two-phase rotating coordinate system.

[0037] S2.3 The voltage components in the two-phase rotating coordinate system are subjected to phase-locked control by a proportional-integral controller, and the real-time voltage phase angle of the power grid is obtained after integral calculation.

[0038] Phase-locked loop (PLL) control provides a phase reference synchronized with the grid voltage for the entire control system, ensuring the accuracy of subsequent coordinate transformations and control calculations, and keeping the output of the hydrogen production power source synchronized with the grid.

[0039] In some embodiments, the phase-locked loop (PLL) may employ a dual second-order generalized integrator PLL to improve the PLL accuracy under conditions of grid voltage imbalance or distortion.

[0040] In some embodiments, the phase-locked loop (PLL) may be an adaptive filter-based PLL to enhance the suppression of grid harmonic interference.

[0041] Step 3: Based on the received DC voltage or DC current command value, perform ramp processing on the received command value to ensure a smooth transition at a preset ramp rate, generating a smoothly changing reference signal to avoid sudden command changes impacting the system. The ramped command value is then used as the reference input signal for the DC voltage or DC current controller, enabling the closed-loop controller to precisely regulate the output DC voltage or DC current.

[0042] See Figure 6 Ramp processing converts abrupt command values ​​into gradual signals, avoiding overshoot and oscillation in the control system and making the regulation of DC voltage or DC current smoother and more stable.

[0043] In some embodiments, the slope of the ramp treatment can be adaptively adjusted according to the temperature or operating status of the electrolyzer, using a gentler ramp rate when the electrolyzer temperature is low and a faster ramp rate when the electrolyzer temperature rises, in order to improve the system response speed.

[0044] Step 4: Based on the DC voltage command value or DC current command value generated in Step 3, and combined with the actual values ​​of the total DC voltage and total DC current collected, a closed-loop control is performed through a proportional-integral controller to generate an active current setpoint in a rotating coordinate system, which is used for coordinate transformation and modulation.

[0045] 1) In DC voltage control mode, the error signal between the DC voltage command value and the actual measured DC voltage value is calculated. This error signal is used as the input signal of the proportional-integral controller, and after control calculation, the active current setpoint is output. In this mode, the actual measured value of the output DC current is monitored in real time. When the actual measured value of the current exceeds the preset maximum allowable DC current value, the DC current limiting logic is triggered, forcibly clamping the active current setpoint to the upper limit corresponding to the maximum allowable DC current value, thereby indirectly limiting the actual output current and protecting the electrolytic cell and equipment safety.

[0046] 2) In DC current control mode, the error signal between the DC current command value and the actual measured DC current value is calculated. This error signal is used as the input signal of the proportional-integral controller (PIC), and after control calculation, the active current setpoint is output. In this mode, the output DC voltage is monitored in real time. When the DC voltage exceeds the preset maximum allowable DC voltage value, the DC voltage limiting logic is triggered, limiting the active current setpoint to the maximum allowable DC voltage value. (See [reference]). Figure 7 .

[0047] In actual operation, the control mode is selected according to the hydrogen production conditions: when the electrolyzer temperature is low and the resistance is high, the DC voltage control mode is selected for low-power electrolysis hydrogen production; after the electrolyzer temperature rises, the DC current control mode is switched to high-power electrolysis hydrogen production.

[0048] DC voltage control is suitable for the initial cold-state operation of the electrolyzer in hydrogen production, achieving safe low-power startup through a stable DC voltage output. DC current control is suitable for the stable operation phase of hydrogen production, achieving high-power, high-efficiency hydrogen production through a stable DC current output. A limiting protection mechanism ensures that, under any control mode, another parameter not directly controlled will not abnormally increase due to changes in operating conditions, avoiding equipment damage or safety hazards caused by a single loop malfunction. The two modes can be automatically or manually switched according to the characteristics of the electrolyzer, ensuring stable operation of the hydrogen production power supply across the entire operating range.

[0049] In some embodiments, the switching between DC voltage control mode and DC current control mode can be automatically triggered according to the temperature of the electrolytic cell. When the temperature of the electrolytic cell is detected to reach a preset temperature threshold, the switching from DC voltage control mode to DC current control mode is automatic.

[0050] In some embodiments, the proportional-integral controller may be replaced by a proportional-integral-derivative controller or a fuzzy logic controller to adapt to different dynamic response requirements.

[0051] In some embodiments, the maximum permissible DC current and the maximum permissible DC voltage can be dynamically adjusted based on the rated parameters of the electrolyzer and the actual operating temperature.

[0052] In some embodiments, the maximum permissible DC current and the maximum permissible DC voltage can be dynamically adjusted based on the rated parameters of the electrolyzer and the actual operating temperature to maximize hydrogen production efficiency while protecting equipment safety.

[0053] Step 5: Based on the error between the actual reactive power value and the reactive power command value, a proportional-integral controller is used for closed-loop control to generate a reactive current setpoint in a rotating coordinate system, which is used for coordinate transformation and modulation. (See [link to relevant documentation]). Figure 8 .

[0054] S5.1 Calculate the error signal between the reactive power command value and the actual measured reactive power value.

[0055] S5.2. After the error signal is processed by limiting, it is input into the proportional-integral controller to limit the maximum output change.

[0056] S5.3 Limit the output signal of the proportional-integral controller to a preset range to obtain the reactive current setpoint.

[0057] Reactive power control enables the hydrogen production power source to adjust its reactive power output according to the grid demand and participate in grid reactive power compensation. At the same time, the limiting process avoids overshoot and oscillation during the adjustment process.

[0058] In some embodiments, the proportional-integral controller output for reactive power control is limited to ±0.4 per unit value, and the limiting range can also be adjusted according to the specific needs of the power grid for reactive power regulation capability.

[0059] In some embodiments, the reactive power command value can be dynamically set according to grid dispatch instructions or voltage fluctuations at the grid connection point.

[0060] Step 6: Based on the active current setpoint and reactive current setpoint generated in Step 4 and Step 5, the current setpoint in the rotating coordinate system is converted into an instantaneous current setpoint through inverse Park transformation. Then, a pulse signal is generated through carrier phase-shift modulation and distributed to multiple parallel power modules to drive the coordinated output of each power module.

[0061] S6.1. The active current setpoint and reactive current setpoint are converted into instantaneous current setpoint in a two-phase stationary coordinate system by inverse Park transformation and combined with the grid voltage phase angle obtained in step 2.

[0062] S6.2. Carrier phase-shift modulation is applied to the instantaneous current setpoint. According to the number of parallel power modules, a carrier signal with the corresponding phase is allocated to each power module to generate the drive pulse of each power module.

[0063] S6.3 The generated drive pulses are distributed to each power module through the fiber optic distribution board to control the switching action of each power module.

[0064] Carrier phase-shift modulation technology achieves a significant increase in the equivalent switching frequency by uniformly staggering the phases of the carrier signals of each power module, effectively reducing the harmonic content of the output current. Simultaneously, the current load is evenly distributed among the power modules, improving the system's power output capability and reliability.

[0065] In some embodiments, when a power module fails and is disconnected, the controller recalculates the carrier phase shift angle of each module based on the number of remaining power modules and redistributes the modulation pulses, enabling the system to continue operating without interruption.

[0066] In some embodiments, carrier phase shift modulation can be implemented using either sinusoidal pulse width modulation or space vector pulse width modulation.

[0067] In some embodiments, the phase angle required for the inverse Park transformation can be directly obtained from the grid voltage phase angle in step 2 by the phase-locked loop, or a preset compensation angle can be superimposed on it to optimize the power factor.

[0068] Step 7: Based on the detected power module fault signal, the faulty module is removed from the system, and the carrier phase shift modulation calculation and pulse distribution are recalculated according to the number of remaining normal modules, so that the system can continue to operate under the de-capacity condition to ensure the continuity of the hydrogen production process.

[0069] S7.1 Real-time monitoring of the status signals of each power module; when a fault is detected in a power module, the module is determined to be a faulty module.

[0070] S7.2 Perform a whole-machine bypass operation to disconnect the faulty module from the parallel system.

[0071] S7.3. Based on the number of normal power modules remaining after the removal, recalculate the carrier phase shift angle of each module.

[0072] S7.4. Generate new drive pulses according to the recalculated carrier phase shift angle, distribute them to the remaining normal power modules, and the system continues to unlock and operate.

[0073] This fault-tolerant mechanism enables the hydrogen production power supply to continue operating even if some power modules fail, avoiding the shutdown of the entire system due to the failure of a single module, and significantly improving the utilization rate and operational reliability of the hydrogen production system.

[0074] In some embodiments, a redundant power module can be preset, and when a faulty module is disconnected, the redundant module is automatically put into operation, so that the system can still operate at rated power and further improve system reliability.

[0075] In some embodiments, the detection of a faulty module can be determined by comprehensively analyzing one or more signals, such as the module output current, module temperature, or communication status.

[0076] In some embodiments, fault-tolerant control also includes isolation protection for faulty modules, which prevents the fault from spreading to other normal modules by disconnecting the faulty module from the DC bus and the AC side.

[0077] A simulation model of this control method was built on the RTDS real-time digital simulation platform. The electrolytic cell was equivalently represented by a fixed resistor model, the value of which was calculated and determined based on the rated voltage and rated DC current of the electrolytic cell. Simulation results show that the total DC current output by the system reaches 19kA, the current waveform is smooth and stable, the dynamic response is rapid, and all performance indicators meet the design requirements. Figure 9 The waveform of the total DC current output by the RTDS simulation model of the hydrogen production power supply in this embodiment is shown.

[0078] Correspondingly, this application also provides a control system for a hydrogen production power source based on an MCSC topology, including: The phase-locked loop control module is used to continuously acquire the real-time phase angle of the grid voltage during the operation of the hydrogen production power supply, as a synchronization reference for the hydrogen production power supply control loop. The mode switching module is used to determine the current control mode according to the operating conditions of the electrolyzer and switch between DC voltage control mode and DC current control mode. The DC voltage control module is used to generate an active current setpoint based on the error between the DC voltage command value and the actual DC voltage value in DC voltage control mode, and to limit the active current setpoint to the limit corresponding to the maximum allowable DC current value when the output DC current exceeds the maximum allowable DC current value. The DC current control module is used to generate an active current setpoint based on the error between the DC current command value and the actual DC current value in DC current control mode, and to limit the active current setpoint to the limit corresponding to the maximum allowable DC voltage value when the output DC voltage exceeds the maximum allowable DC voltage value. The reactive power control module is used to generate a reactive current setpoint based on the error between the reactive power command value and the actual reactive power value on the AC side of the hydrogen production power source. The coordinate transformation and modulation module is used to convert the active current setpoint and the reactive current setpoint into instantaneous current setpoints, and modulate them in combination with the real-time phase angle of the grid voltage to generate drive pulses for each parallel power module, so as to control the working state of each power module.

[0079] It should be noted that, in the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple modules may be combined or integrated into another device, or some features may be ignored or not executed. The modules described as separate components may or may not be physically separated. The components shown as modules may be one or more physical units, that is, they may be located in one place or distributed in multiple different places. Some or all of the modules can be selected to achieve the purpose of the solution in this embodiment according to actual needs.

[0080] Furthermore, in the various embodiments of the present invention, the modules can be integrated into one processing unit, or each module can exist physically separately, or two or more modules can be integrated into one unit. The integrated unit described above can be implemented in hardware or as a software functional unit.

[0081] An electronic device provided in this application includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the steps of the control method for a hydrogen production power source based on the MCSC topology described in any of the above embodiments.

[0082] Another electronic device provided in this application embodiment may further include: an input port connected to a processor for transmitting multimodal data collected by an external acquisition device to the processor; a display unit connected to the processor for displaying the processor's processing results to the outside world; and a communication module connected to the processor for enabling communication between the electronic device and the outside world. The display unit may be a display panel, a laser scanning display, etc.; the communication method adopted by the communication module includes, but is not limited to, Mobile High Definition Link (HML), Universal Serial Bus (USB), High Definition Multimedia Interface (HDMI), and wireless connection (including Wi-Fi, Bluetooth, Bluetooth Low Energy, and IEEE 802.11s-based communication technology).

[0083] This application provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the steps of the control method for a hydrogen production power source based on an MCSC topology as described in any of the above embodiments.

[0084] For descriptions of the control system, electronic equipment, and computer-readable storage medium of the hydrogen production power supply based on the MCSC topology provided in this application, please refer to the detailed description of the corresponding parts in the control method of the hydrogen production power supply based on the MCSC topology provided in this application, which will not be repeated here. Furthermore, parts of the technical solutions provided in this application that are consistent with the implementation principles of corresponding technical solutions in the prior art have not been described in detail to avoid excessive elaboration.

[0085] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A control method for a hydrogen production power source based on an MCSC topology, characterized in that, Includes the following steps: During the operation of the hydrogen production power source, the real-time phase angle of the grid voltage is continuously acquired as a synchronization reference for the hydrogen production power source control loop. The current control mode is determined based on the operating conditions of the electrolyzer: In DC voltage control mode, an active current setpoint is generated based on the error between the DC voltage command value and the actual DC voltage value. When the output DC current exceeds the maximum allowable DC current value, the active current setpoint is limited to the limit corresponding to the maximum allowable DC current value. In DC current control mode, an active current setpoint is generated based on the error between the DC current command value and the actual DC current value. When the output DC voltage exceeds the maximum allowable DC voltage value, the active current setpoint is limited to the limit corresponding to the maximum allowable DC voltage value. The reactive current setpoint is generated based on the error between the reactive power command value and the actual reactive power value on the AC side of the hydrogen production power source. The active current setpoint and reactive current setpoint are converted into instantaneous current setpoints, and modulated in combination with the real-time phase angle of the grid voltage to generate drive pulses for each parallel power module, thereby controlling the operating state of each power module.

2. The control method for a hydrogen production power source based on an MCSC topology according to claim 1, characterized in that, Determining the current control mode based on the operating conditions of the electrolyzer includes: When the temperature of the electrolytic cell is lower than the preset temperature threshold, it enters DC voltage control mode; When the temperature of the electrolytic cell reaches or exceeds the preset temperature threshold, it enters the DC current control mode.

3. The control method for a hydrogen production power source based on an MCSC topology according to claim 2, characterized in that, During the switching process between the DC voltage control mode and the DC current control mode, the command value after the switch is first subjected to ramp processing, so that the command value smoothly transitions from the current value to the target value at a preset ramp rate.

4. The control method for a hydrogen production power source based on an MCSC topology according to claim 1, characterized in that, The step of converting the active current setpoint and the reactive current setpoint into an instantaneous current setpoint includes: Using the active current setpoint as the d-axis component and the reactive current setpoint as the q-axis component, and combining the real-time phase angle of the grid voltage, the current setpoint in the two-phase rotating coordinate system is converted into the instantaneous current setpoint in the two-phase stationary coordinate system through inverse Park transformation.

5. The control method for a hydrogen production power source based on an MCSC topology according to claim 1, characterized in that, The process of modulating the real-time phase angle of the grid voltage to generate drive pulses for each parallel power module includes: The phase offset of the carrier signal of each power module is determined according to the number of parallel power modules, so that the carrier signals of each power module are uniformly staggered in phase; the instantaneous current setpoint is compared with the carrier signal of the corresponding phase of each power module to generate the driving pulse of each power module.

6. The control method for a hydrogen production power source based on an MCSC topology according to claim 1, characterized in that, The determination of the active current setpoint includes: A proportional-integral controller is used to perform closed-loop control on the error signal between the DC voltage command value and the actual DC voltage value, or the error signal between the DC current command value and the actual DC current value.

7. The control method for a hydrogen production power source based on an MCSC topology according to claim 1, characterized in that, The determination of the reactive current setpoint includes: A proportional-integral controller is used to perform closed-loop control on the error signal between the reactive power command value and the actual reactive power value; the output of the proportional-integral controller is all subjected to amplitude limiting processing to obtain the corresponding current setpoint value.

8. The control method for a hydrogen production power source based on an MCSC topology according to claim 1, characterized in that, Also includes: When a parallel power module fails, the failed power module is disconnected from the parallel system. The carrier phase shift angle of each power module is recalculated based on the number of remaining normal power modules. New drive pulses are generated according to the recalculated carrier phase shift angles to control the remaining normal power modules to continue operating.

9. The control method for a hydrogen production power source based on an MCSC topology according to claim 1, characterized in that, When the hydrogen production power source starts up, multiple parallel power modules are controlled to be put into operation one by one at preset intervals; when the hydrogen production power source stops, multiple parallel power modules are controlled to be deactivated simultaneously.

10. A control method for a hydrogen production power source based on an MCSC topology as described in any one of claims 1-9, characterized in that, include: The phase-locked loop control module is used to continuously acquire the real-time phase angle of the grid voltage during the operation of the hydrogen production power supply, as a synchronization reference for the hydrogen production power supply control loop. The mode switching module is used to determine the current control mode according to the operating conditions of the electrolyzer and switch between DC voltage control mode and DC current control mode. The DC voltage control module is used to generate an active current setpoint based on the error between the DC voltage command value and the actual DC voltage value in DC voltage control mode, and to limit the active current setpoint to the limit corresponding to the maximum allowable DC current value when the output DC current exceeds the maximum allowable DC current value. The DC current control module is used to generate an active current setpoint based on the error between the DC current command value and the actual DC current value in DC current control mode, and to limit the active current setpoint to the limit corresponding to the maximum allowable DC voltage value when the output DC voltage exceeds the maximum allowable DC voltage value. The reactive power control module is used to generate a reactive current setpoint based on the error between the reactive power command value and the actual reactive power value on the AC side of the hydrogen production power source. The coordinate transformation and modulation module is used to convert the active current setpoint and the reactive current setpoint into instantaneous current setpoints, and modulate them in combination with the real-time phase angle of the grid voltage to generate drive pulses for each parallel power module, so as to control the working state of each power module.

Images