Parallel electrolytic hydrogen production power supply and control method thereof

Abstract

The invention discloses a parallel electrolytic hydrogen production power supply and a control method thereof. The parallel electrolytic hydrogen production power supply comprises a twelve-pulse rectifier transformer, the alternating current ends of the two first rectifiers are respectively connected with two three-phase joints on the alternating current side of the twelve-pulse rectifier transformer; the alternating current ends of the two second rectifiers are respectively connected with two three-phase connectors on the alternating current side of the twelve-pulse rectifier transformer; the direct-current end anodes of all the first rectifiers and the second rectifiers are electrically connected to form an anode of a direct-current voltage bus, and the direct-current end cathodes of all the first rectifiers and the second rectifiers are electrically connected to form a cathode of the direct-current voltage bus; the first rectifier is a silicon controlled rectifier (SCR), and the second rectifier is an insulated gate bipolar transistor (IGBT) full-control rectifier. Compared with the prior art, the advantages of the SCR rectifier and the IGBT full-control rectifier are combined, so that the direct-current voltage regulation range is wide, the power response speed is high, the electric energy quality is high, and the current endurance capability is remarkably improved. And secondly, a harmonic wave and reactive power treatment device does not need to be additionally arranged, the comprehensive conversion efficiency is also greatly improved, and the requirements of subsequent large-scale and high-capacity hydrogen production equipment can be better met.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen production by electrolysis of water, and in particular to a parallel type hydrogen production by electrolysis power supply and a control method thereof. Background Art

[0002] Hydrogen energy is a secondary energy source with a wide range of sources, clean and carbon-free, and rich application scenarios. It is an ideal interconnected medium to promote green energy transformation and support the large-scale development of renewable energy. Through the production of hydrogen through electrolysis of new energy and the comprehensive utilization of hydrogen energy in multiple ways (including power generation, automobile fuel, chemical industry, etc.), the flexible conversion between electric energy carriers and hydrogen energy carriers can be realized, which can get rid of the single dependence of new energy on the power grid and promote the large-scale consumption of new energy.

[0003] In the field of hydrogen production by water electrolysis, there are technical routes such as alkaline water electrolysis (AWE), proton exchange membrane (PEM) water electrolysis, solid oxide electrolysis (SOEC), and anion exchange membrane electrolysis (AEM). Currently, there are two relatively mature technologies: AWE and PEM. Among them, AWE, which uses alkaline solution as electrolyte, is the earliest developed and currently the most mature and lowest-cost water electrolysis hydrogen production technology.

[0004] Alkaline water electrolysis (AWE) requires a DC electrolysis power supply to rectify the AC power of the grid into a DC power supply. The technical routes of its power supply can be divided into two major routes: thyristor (SCR) and insulated gate bipolar transistor (IGBT).

[0005] The silicon controlled rectifier composed of SCR generally adopts multi-pulse rectification mode, which has the advantages of large current, mature application, low investment and good reliability. Its disadvantage is that it has high harmonic problems, low power quality, and needs to be equipped with harmonic compensation or anti-harmonic devices, resulting in low overall conversion efficiency. In addition, the thyristor power supply has a slow response speed and power regulation speed, and a limited regulation range, which is not suitable for the high volatility of new energy power grids.

[0006] The fully controlled rectifier composed of IGBT has the characteristics of low conduction voltage drop and fast switching speed, fast response speed, low harmonic content, and high comprehensive conversion efficiency. It has outstanding advantages in terms of grid friendliness, power response speed, voltage ripple, and comprehensive efficiency, and is more suitable for large-scale new energy volatility hydrogen production scenarios. However, its disadvantage is that the current resistance of IGBT is poor. Summary of the invention

[0007] The purpose of the invention is to solve the technical problems of low power quality, slow power response speed, limited DC voltage regulation range of the existing SCR-based electrolysis hydrogen production power supply, and poor current carrying capacity of the IGBT-based electrolysis hydrogen production power supply.

[0008] To achieve the above-mentioned purpose, the present invention proposes a parallel electrolysis hydrogen production power supply and a control method thereof, wherein two sets of three-phase bridge thyristor rectifiers are connected in parallel to form a twelve-pulse rectified DC voltage power supply, and two sets of three-phase bridge fully-controlled rectifiers are connected in parallel to be responsible for power quality management and rapid power response, thereby complementing the advantages and disadvantages of SCR thyristor rectifiers and IGBT fully-controlled rectifiers.

[0009] On the one hand, a parallel electrolysis hydrogen production power supply is provided, comprising:

[0010] Twelve-pulse rectifier transformer;

[0011] Two first rectifiers, the AC ends of which are respectively connected to two three-phase connectors on the AC side of the twelve-pulse rectifier transformer;

[0012] Two second rectifiers, the AC ends of which are respectively connected to two three-phase connectors on the AC side of the twelve-pulse rectifier transformer;

[0013] The positive electrodes of the DC ends of all the first rectifiers and the second rectifiers are electrically connected to form a positive electrode of the DC voltage bus, and the negative electrodes of the DC ends of all the first rectifiers and the second rectifiers are electrically connected to form a negative electrode of the DC voltage bus;

[0014] The first rectifier is an SCR silicon-controlled rectifier, and the second rectifier is an IGBT fully-controlled rectifier.

[0015] Therefore, the above scheme combines the advantages of SCR silicon-controlled rectifiers and IGBT fully-controlled rectifiers, making the DC voltage regulation range of the parallel electrolysis hydrogen production power supply wide, the power response speed fast, the power quality high, and the current resistance significantly improved. Secondly, there is no need to install additional harmonic and reactive power control devices, and the overall conversion efficiency is also greatly improved, which can better meet the needs of subsequent large-scale and large-capacity hydrogen production equipment. Thirdly, the electrolysis capacity of the electrolysis hydrogen production device powered by the above parallel electrolysis hydrogen production power supply is larger.

[0016] On the other hand, an electrolytic hydrogen production device is provided, comprising the above-mentioned parallel electrolytic hydrogen production power supply and an electrolytic cell, wherein the electrolytic cell is connected between the positive electrode and the negative electrode of the DC voltage bus.

[0017] In another aspect, a control method for a parallel electrolysis hydrogen production power source is provided, comprising the following steps:

[0018] Obtaining reactive power and harmonic components in the three-phase load line current flowing into the secondary side of the transformer of the two second rectifiers;

[0019] Performing dq transformation on reactive power and harmonic components in the three-phase load line current corresponding to the two second rectifiers to obtain respective first d-axis current components and first q-axis current components;

[0020] Performing current tracking output control on respective first d-axis current components and first q-axis current components to obtain respective d-axis components and q-axis components of modulation voltages;

[0021] After the d-axis component and the q-axis component of the respective modulation voltages are inversely dq-converted, they are respectively compared with the triangular carrier to generate a drive signal corresponding to the second rectifier.

[0022] In some embodiments, obtaining reactive power and harmonic components in the three-phase load line current flowing into the secondary side of the transformer of the two second rectifiers includes:

[0023] The three-phase load line currents on the secondary sides of the transformers flowing into the two second rectifiers are respectively converted by dq to obtain respective second d-axis currents and second q-axis currents;

[0024] The second d-axis current of each of them is passed through a low-pass filter to retain its DC component, and the second q-axis current is set to 0. After reverse dq transformation, it is subtracted from the three-phase load line current on the secondary side of the corresponding transformer to obtain the reactive and harmonic components of the three-phase load line current on the secondary side of the transformer flowing into the two second rectifiers.

[0025] In some embodiments, current tracking output control of respective first d-axis current components and first q-axis current components includes: performing difference comparison between respective first d-axis current components and first q-axis current components and third d-axis current components and third q-axis current components, respectively, and outputting respective d-axis components and q-axis components of modulation voltages through PI tracking control; wherein the third d-axis current component and the third q-axis current component are components of the actual current drawn by the corresponding second rectifier after dq transformation.

[0026] In order to respond to the rapid change of hydrogen production power, in some embodiments, before performing a difference comparison between the respective first d-axis current component and the third d-axis current component, the method further includes: superimposing the respective auxiliary hydrogen production active current component on the respective first d-axis current component.

[0027] In order to offset the coupling variable so that the two variables are decoupled from each other in their respective control loops and are independent of each other, in some embodiments, before the d-axis component and the q-axis component of the respective modulation voltage are subjected to inverse dq transformation, the following is further included:

[0028] Superimposing the product of the third d-axis current component, the voltage frequency, and the connection inductance value, and the product of the third q-axis current component, the voltage frequency, and the connection inductance value, respectively, on the d-axis component and the q-axis component of the respective modulation voltages;

[0029] The third d-axis current component and the third q-axis current component are components of the actual current drawn by the corresponding second rectifier after dq transformation.

[0030] In order to speed up the current loop tracking control speed, in some embodiments, before the d-axis component and the q-axis component of the respective modulation voltage are subjected to inverse dq transformation, the following steps are further included:

[0031] Respective voltage feed-forward components are superimposed on the d-axis component and the q-axis component of the respective modulation voltages, and the respective voltage feed-forward components are obtained by dq transformation of the three-phase-to-ground voltages on the secondary sides of the respective transformers.

[0032] On the other hand, a computer device is provided, comprising a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the above method.

[0033] On the other hand, a computer-readable storage medium is provided, on which a computer program / instruction is stored, and when the computer program / instruction is executed by a processor, the steps of the above method are implemented.

[0034] The present invention has at least the following technical effects or advantages:

[0035] 1. By combining the SCR silicon-controlled rectifier and the IGBT fully-controlled rectifier in parallel, the DC voltage regulation range of the present invention is wide, the power response speed is fast, the power quality is high, and the current carrying capacity is significantly improved, and it is more suitable for application scenarios with large DC rectification current and low voltage.

[0036] 2. There is no need to install additional harmonic and reactive power control devices, and the overall conversion efficiency can be greatly improved, which can better meet the subsequent large-scale and large-capacity hydrogen production equipment needs.

[0037] 3. The electrolysis capacity of the hydrogen production device powered by the parallel electrolysis hydrogen production power supply of the present invention is larger. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a circuit connection diagram of a parallel electrolysis hydrogen production power supply in one embodiment of the present invention;

[0039] Figure 2 This is a circuit connection diagram of an electrolytic hydrogen production device in one embodiment of the present invention;

[0040] Figure 3 This is a control principle diagram of a first IGBT fully-controlled rectifier in one embodiment of the present invention;

[0041] Figure 4 1 is a control principle diagram of a second IGBT fully-controlled rectifier in one embodiment of the present invention. DETAILED DESCRIPTION

[0042] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0043] Embodiment 1

[0044] like Figure 1 As shown, a parallel electrolysis hydrogen production power supply includes: a twelve-pulse rectifier transformer 1, a first SCR silicon-controlled rectifier 21, a second SCR silicon-controlled rectifier 22, a first IGBT fully-controlled rectifier 31 and a second IGBT fully-controlled rectifier 32.

[0045] The AC ends of the first SCR thyristor rectifier 21 and the second SCR thyristor rectifier 22 are respectively connected to two three-phase connectors on the AC side of the twelve-pulse rectifier transformer 1 (the first SCR thyristor rectifier 21 is connected to the three-phase connector of the secondary star winding of the twelve-pulse rectifier transformer 1, and the second SCR thyristor rectifier 22 is connected to the three-phase connector of the secondary delta winding of the twelve-pulse rectifier transformer 1). The AC ends of the first IGBT fully-controlled rectifier 31 and the second IGBT fully-controlled rectifier 32 are respectively connected to two three-phase connectors on the AC side of the twelve-pulse rectifier transformer 1 (the first IGBT fully-controlled rectifier 31 is connected to the three-phase connector of the secondary star winding of the twelve-pulse rectifier transformer 1, and the second IGBT fully-controlled rectifier 32 is connected to the three-phase connector of the secondary delta winding of the twelve-pulse rectifier transformer 1). The positive poles of the DC ends of the two SCR silicon-controlled rectifiers (21 and 22) and the two IGBT fully-controlled rectifiers (31 and 32) are electrically connected to form the positive pole of the DC voltage bus, and the negative poles are electrically connected to form the negative pole of the DC voltage bus.

[0046] Preferably, a capacitor is provided between the positive and negative electrodes of the DC voltage busbar to achieve voltage division and DC voltage ripple suppression.

[0047] Figure 1 in,u A1 、u B1 、u C1 and u A2 、u B2 、u C2 Represent the three-phase voltage to ground on the AC side of the twelve-pulse rectifier transformer 1, i A1 、i B1 、i C1 and i A2 、i B2 、i C2 Respectively represent the three-phase load line current on the AC side of the twelve-pulse rectifier transformer 1, i a1 、i b1 、i c1 and i a2 、i b2 、i c2represents the current drawn by the first IGBT fully-controlled rectifier 31 and the second IGBT fully-controlled rectifier 32 respectively, and the DC voltage at the output end of the parallel electrolysis hydrogen production power supply is u dc ,u dc , the size of which is controlled by the conduction angle α of the first SCR silicon-controlled rectifier 21 and the second SCR silicon-controlled rectifier 22.

[0048] Embodiment 2

[0049] like Figure 2 As shown, an electrolytic hydrogen production device includes the above-mentioned parallel electrolytic hydrogen production power supply and an electrolytic cell 4, and the electrolytic cell 4 is connected between the positive electrode and the negative electrode of the DC voltage bus.

[0050] Embodiment 3

[0051] A control method for a parallel electrolysis hydrogen production power source comprises the following steps:

[0052] Obtaining reactive power and harmonic components in the three-phase load line current on the secondary side of the transformer flowing into the two second rectifiers (IGBT fully controlled rectifiers);

[0053] Performing dq transformation on reactive power and harmonic components in the three-phase load line current corresponding to the two second rectifiers to obtain respective first d-axis current components and first q-axis current components;

[0054] Performing current tracking output control on respective first d-axis current components and first q-axis current components to obtain respective d-axis components and q-axis components of modulation voltages;

[0055] After the d-axis component and the q-axis component of the respective modulation voltages are inversely dq-converted, they are respectively compared with the triangular carrier to generate a drive signal corresponding to the second rectifier.

[0056] Preferably, obtaining reactive power and harmonic components in the three-phase load line current flowing into the secondary side of the transformer of the two second rectifiers comprises:

[0057] The three-phase load line currents on the secondary sides of the transformers flowing into the two second rectifiers are respectively converted by dq to obtain respective second d-axis currents and second q-axis currents;

[0058] The second d-axis current of each of them is passed through a low-pass filter to retain its DC component, and the second q-axis current is set to 0. After reverse dq transformation, it is subtracted from the three-phase load line current on the secondary side of the corresponding transformer to obtain the reactive and harmonic components of the three-phase load line current on the secondary side of the transformer flowing into the two second rectifiers.

[0059] Preferably, performing current tracking output control on the respective first d-axis current component and the first q-axis current component comprises: performing difference comparison between the respective first d-axis current component and the first q-axis current component and the third d-axis current component and the third q-axis current component, respectively, and outputting the respective d-axis component and q-axis component of the modulation voltage after PI tracking control;

[0060] The third d-axis current component and the third q-axis current component are components of the actual current drawn by the corresponding second rectifier after dq transformation.

[0061] Preferably, before performing a difference comparison between the respective first d-axis current component and the third d-axis current component, the method further includes: superimposing the respective auxiliary hydrogen production active current component on the respective first d-axis current component.

[0062] Preferably, before the d-axis component and q-axis component of each modulation voltage are subjected to inverse dq transformation, the step also includes: superimposing the product of the respective third d-axis current component and the voltage frequency and the connection inductance value and the product of the third q-axis current component and the voltage frequency and the connection inductance value on the d-axis component and the q-axis component of the respective modulation voltage; wherein the third d-axis current component and the third q-axis current component are the components of the actual current drawn by the corresponding second rectifier after dq transformation.

[0063] Preferably, before the d-axis component and q-axis component of the respective modulation voltage are subjected to inverse dq transformation, the method also includes: superimposing respective voltage feedforward components on the d-axis component and q-axis component of the respective modulation voltage, respectively, and the respective voltage feedforward components are obtained by dq transformation of the three-phase-to-ground voltage on the secondary side of the respective transformer.

[0064] Specifically, Figure 3 The control principle diagram of the first IGBT fully-controlled rectifier 31 is shown, and the control method of the first IGBT fully-controlled rectifier 31 is as follows:

[0065] The first IGBT fully controlled rectifier 31 collects the three-phase load line current i on the secondary side of the transformer A1 、i B1 、i C1 After dq transformation, we can get the i in the stationary dq coordinates D1 、i Q1 The phase angles sinθ and cosθ used in the dq transformation are the three-phase voltage u between the secondary side of the transformer and the ground. A1 、u B1 、u C1 The voltage phase angle after the phase-locked loop is locked. At this time, the d-axis current i D1 The fundamental component represents the active current component drawn by the rectifier, and the periodic frequency component represents the harmonic component drawn by the rectifier; the q-axis current i Q1The fundamental component represents the reactive current component drawn by the rectifier, and the periodic frequency component represents the harmonic component drawn by the rectifier. D1 The DC component is retained by the low-pass filter, i Q1 Set to 0, and then transform it together with the original three-phase load line current i through reverse dq transformation A1 、i B1 、i C1 Subtract, and get i hA1 、i hB1 、i hC1 Only the three-phase load line current i is retained A1 、i B1 、i C1 The reactive power and harmonic components in the current are the current components that need to be absorbed and compensated by the first IGBT fully controlled rectifier 31. hA1 、i hB1 、i hC1 The current tracking output control will i hA1 、i hB1 、i hC1 After dq transformation, we can get the i in the stationary dq coordinates d1 、i q1 The current tracking control is performed on the d-axis component i to respond to the rapid change of hydrogen production power. d1 The auxiliary hydrogen production active current component I1 is superimposed on it. In current tracking control, i d1 +I c1 with i q1 The actual current i drawn by the fully controlled rectifier 1 a1 、i b1 、i c1 The actual i after dq transformation cd1 、i cq1 After comparing with the difference, the modulation voltage in dq coordinates is output through PI tracking control. d1 +I c1 with i cd1 、i q1 with i cq1 When PI control is performed, there is mutual coupling between the two controlled variables, so i and cd1 *wl (w is the voltage frequency, l is the connection inductance value of the first IGBT fully controlled rectifier 31) and i cq1 *wl to offset the coupling variables, making the two variables decoupled and independent of each other in their respective control loops. In order to speed up i cd1 with i cq1 The current loop tracks the control speed and introduces u into the output modulation voltage component. D1 、uQ1 The voltage feedforward component is composed of u A1 、u B1 、u C1 After dq transformation, the phase angles sinθ and cosθ used in the dq inverse transformation are the three-phase voltage u between the secondary side of the transformer and the ground A1 、u B1 、u C1 The voltage phase angle after phase locking by the phase-locked loop generates the final modulation control voltage u cd1 、u cq1 .u cd1 、u cq1 After the inverse dq transformation, the three-phase sinusoidal modulation voltage u is generated a1 、u b1 、u c1 The phase angles sinθ and cosθ used in the dq inverse transformation are the three-phase voltage u between the secondary side of the transformer and the ground. A1 、u B1 、u C1 The voltage phase angle after phase locking by the phase-locked loop, the modulation voltage u a1 、u b1 、u c1 After comparison with the triangular carrier, an IGBT driving signal of the bridge arm corresponding to the bridge arm commutation device of the first IGBT fully-controlled rectifier 31 is generated, wherein the triangular carrier signal can be implemented using a cycle counting register of a DSP.

[0066] Figure 4 The control principle diagram of the second IGBT fully-controlled rectifier 32 is shown, and the control method of the second IGBT fully-controlled rectifier 32 is as follows:

[0067] The second IGBT fully controlled rectifier 32 collects the three-phase load line current i on the secondary side of the transformer A2 、i B2 、i C2 After dq transformation, we can get the i in the stationary dq coordinates D2 、i Q2 The phase angles sinθ and cosθ used in the dq transformation are the three-phase voltage u between the secondary side of the transformer and the ground. A2 、u B2 、u C2 The voltage phase angle after the phase-locked loop is locked. At this time, the d-axis current i D2 The fundamental component represents the active current component drawn by the rectifier, and the periodic frequency component represents the harmonic component drawn by the rectifier; the q-axis current i Q2 The fundamental component represents the reactive current component drawn by the rectifier, and the periodic frequency component represents the harmonic component drawn by the rectifier. D2 The fundamental component is retained by a low-pass filter, i Q2Set to 0, and then transform it together with the original three-phase load line current i through reverse dq transformation A2 、i B2 、i C2 Subtract, and we get i hA2 、i hB2 、i hC2 Only the three-phase load line current i is retained A2 、i B2 、i C2 The reactive power and harmonic components in the current are the current components that need to be absorbed and compensated by the second IGBT fully controlled rectifier 32. hA2 、i hB2 、i hC2 The current tracking output control will i hA2 、i hB2 、i hC2 After dq transformation, we can get the i in the stationary dq coordinates d2 、i q2 The current tracking control is performed on the d-axis component i to respond to the rapid change of hydrogen production power. d2 The auxiliary hydrogen production active current component I2 is superimposed on it. In current tracking control, i d2 +I c2 with i q2 The actual current i drawn by the second IGBT fully controlled rectifier 32 is a2 、i b2 、i c2 The actual i after dq transformation cd2 、i cq2 After comparing with the difference, the modulation voltage in dq coordinates is output through PI tracking control. d2 +I c2 with i cd2 、i q2 with i cq2 When PI control is performed, there is mutual coupling between the two controlled variables, so i and cd2 *wl (w is the voltage frequency, l is the connection inductance value of the second IGBT fully controlled rectifier 32) and i cq2 *wl to offset the coupling variables, making the two variables decoupled and independent of each other in their respective control loops. In order to speed up i cd2 with i cq2 The current loop tracks the control speed and introduces u into the output modulation voltage component. D2 、u Q2 The voltage feedforward component is composed of u A2 、u B2 、u C2After dq transformation, the phase angles sinθ and cosθ used in the dq inverse transformation are the three-phase voltage u between the secondary side of the transformer and the ground A2 、u B2 、u C2 The voltage phase angle after phase locking by the phase-locked loop generates the final modulation control voltage u cd2 、u cq2 .u cd2 、u cq2 After the inverse dq transformation, the three-phase sinusoidal modulation voltage u is generated a2 、u b2 、u c2 The phase angles sinθ and cosθ used in the dq inverse transformation are the three-phase voltage u between the secondary side of the transformer and the ground. A2 、u B2 、u C2 The voltage phase angle after phase locking by the phase-locked loop, the modulation voltage u a2 、u b2 、u c2 After comparison with the triangular carrier, an IGBT driving signal of the bridge arm corresponding to the bridge arm commutation device of the second IGBT fully-controlled rectifier 32 is generated, wherein the triangular carrier signal can be implemented using a cycle counting register of a DSP.

[0068] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0069] Similarly, it should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this disclosed method should not be interpreted as reflecting the intention that the claimed invention requires more features than those expressly recited in each claim. Rather, as reflected in the claims, inventive aspects lie in less than all of the features of the individual embodiments previously disclosed. Therefore, the claims that follow the detailed description are hereby expressly incorporated into the detailed description, with each claim itself serving as a separate embodiment of the present invention.

[0070] Those skilled in the art will appreciate that the modules or units or groups of the devices in the examples disclosed herein may be arranged in the device as described in the embodiment, or alternatively may be located in one or more devices different from the devices in the example. The modules in the foregoing examples may be combined into one module or may be divided into multiple submodules.

[0071] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or groups in the embodiments may be combined into one module or unit or group, and in addition they may be divided into a plurality of submodules or subunits or subgroups. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0072] Furthermore, those skilled in the art will appreciate that although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features from different embodiments is meant to be within the scope of the present invention and to form different embodiments.

[0073] In addition, some of the embodiments are described herein as methods or combinations of method elements that can be implemented by a processor of a computer system or by other devices that perform the functions. Therefore, a processor with necessary instructions for implementing the method or method elements forms a device for implementing the method or method elements. In addition, the elements described herein of the device embodiments are examples of devices for implementing the functions performed by the elements for the purpose of implementing the invention.

[0074] The various techniques described herein may be implemented in combination with hardware or software, or a combination thereof. Thus, the method and apparatus of the present invention, or some aspects or portions of the method and apparatus of the present invention may be in the form of program codes (i.e., instructions) embedded in a tangible medium, such as a floppy disk, a CD-ROM, a hard disk drive, or any other machine-readable storage medium, wherein when the program is loaded into a machine such as a computer and executed by the machine, the machine becomes a device for practicing the present invention.

[0075] In the case where the program code is executed on a programmable computer, the computing device generally includes a processor, a storage medium readable by the processor (including volatile and non-volatile memory and / or storage elements), at least one input device, and at least one output device. The memory is configured to store the program code; the processor is configured to execute the method of the present invention according to the instructions in the program code stored in the memory.

[0076] By way of example and not limitation, computer readable media include computer storage media and communication media. Computer readable media include computer storage media and communication media. Computer storage media stores information such as computer readable instructions, data structures, program modules or other data. Communication media generally embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transmission mechanism, and includes any information delivery medium. Any combination of the above is also included within the scope of computer readable media.

[0077] As used herein, unless otherwise specified, the use of ordinal numbers "first," "second," "third," etc. to describe common objects merely indicates that different instances of similar objects are involved, and is not intended to imply that the objects so described must have a given order in time, space, order, or in any other manner.

[0078] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments may be envisioned within the scope of the invention thus described. In addition, it should be noted that the language used in this specification is selected primarily for readability and teaching purposes, rather than for explaining or defining the subject matter of the present invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the present invention is illustrative, not restrictive, with respect to the scope of the present invention, which is defined by the appended claims.

[0079] Finally, it should be noted that the present invention does not explain in detail the common knowledge recognized by technicians in this field. The above is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A parallel electrolysis hydrogen production power supply, characterized in that: include: Twelve-pulse rectifier transformer; Two first rectifiers, the AC ends of which are respectively connected to two three-phase connectors on the AC side of the twelve-pulse rectifier transformer; Two second rectifiers, the AC ends of which are respectively connected to two three-phase connectors on the AC side of the twelve-pulse rectifier transformer; The positive electrodes of the DC ends of all the first rectifiers and the second rectifiers are electrically connected to form a positive electrode of the DC voltage bus, and the negative electrodes of the DC ends of all the first rectifiers and the second rectifiers are electrically connected to form a negative electrode of the DC voltage bus; The first rectifier is an SCR silicon-controlled rectifier, and the second rectifier is an IGBT fully-controlled rectifier.

2. A hydrogen production device by electrolysis, characterized in that: It comprises the parallel electrolysis hydrogen production power supply as claimed in claim 1 and an electrolyzer, wherein the electrolyzer is connected between the positive electrode and the negative electrode of the DC voltage bus.

3. A control method for a parallel electrolysis hydrogen production power source as claimed in claim 1, characterized in that: The method comprises the following steps: obtaining reactive power and harmonic components in the three-phase load line current flowing into the secondary side of the transformer of the two second rectifiers; Performing dq transformation on reactive power and harmonic components in the three-phase load line current corresponding to the two second rectifiers to obtain respective first d-axis current components and first q-axis current components; Performing current tracking output control on respective first d-axis current components and first q-axis current components to obtain respective d-axis components and q-axis components of modulation voltages; After the d-axis component and the q-axis component of the respective modulation voltages are inversely dq-converted, they are respectively compared with the triangular carrier to generate a drive signal corresponding to the second rectifier.

4. The control method according to claim 3, characterized in that: Obtaining reactive power and harmonic components in the three-phase load line current flowing into the secondary side of the transformer of the two second rectifiers includes: The three-phase load line currents on the secondary sides of the transformers flowing into the two second rectifiers are respectively converted by dq to obtain respective second d-axis currents and second q-axis currents; The second d-axis current of each of them is passed through a low-pass filter to retain its DC component, and the second q-axis current is set to 0. After reverse dq transformation, it is subtracted from the three-phase load line current on the secondary side of the corresponding transformer to obtain the reactive and harmonic components of the three-phase load line current on the secondary side of the transformer flowing into the two second rectifiers.

5. The control method according to claim 3, characterized in that: Performing current tracking output control on respective first d-axis current components and first q-axis current components includes: After making a difference comparison between the respective first d-axis current component and the first q-axis current component and the third d-axis current component and the third q-axis current component, the d-axis component and the q-axis component of the respective modulation voltage are output through PI tracking control; The third d-axis current component and the third q-axis current component are components of the actual current drawn by the corresponding second rectifier after dq transformation.

6. The control method according to claim 4 or 5, characterized in that: Before performing a difference comparison between the respective first d-axis current component and the third d-axis current component, the method further includes: superimposing the respective auxiliary hydrogen production active current component on the respective first d-axis current component.

7. The control method according to claim 3, characterized in that: Before performing inverse dq transformation on the d-axis component and the q-axis component of the respective modulation voltage, the method further includes: superimposing the product of the third d-axis current component, the voltage frequency, and the connection inductance value, and the product of the third q-axis current component, the voltage frequency, and the connection inductance value, on the d-axis component and the q-axis component of the respective modulation voltage; The third d-axis current component and the third q-axis current component are components of the actual current drawn by the corresponding second rectifier after dq transformation.

8. The control method according to claim 3, characterized in that: Before the d-axis component and q-axis component of the respective modulation voltage are subjected to inverse dq transformation, the method also includes: superimposing respective voltage feedforward components on the d-axis component and q-axis component of the respective modulation voltage, respectively, wherein the respective voltage feedforward components are obtained by dq transformation of the three-phase-to-ground voltage on the secondary side of the respective transformer.

9. A computer device comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement the steps of the method according to any one of claims 3 to 8.

10. A computer-readable storage medium having a computer program / instruction stored thereon, characterized in that: When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 3 to 8 are implemented.

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