Direct current power supply and hydrogen production system

Abstract

This application discloses a DC power supply and a hydrogen production system, belonging to the field of power supply technology. The DC power supply includes a power conversion circuit, a switching element, and a unidirectional conducting element. The positive output terminal of the power conversion circuit is connected to the positive output terminal of the DC power supply, and the negative output terminal of the power conversion circuit is connected to the negative output terminal of the DC power supply. The switching element is disposed between the positive output terminal of the power conversion circuit and the positive output terminal of the DC power supply. The unidirectional conducting element is disposed between the negative output terminal of the power conversion circuit and the negative output terminal of the DC power supply, and the conduction direction of the unidirectional conducting element is from the negative output terminal of the DC power supply to the negative output terminal of the power conversion circuit. This DC power supply optimizes the switching element at the negative output terminal of the power conversion circuit into a unidirectional conducting element, which can save installation space and reduce manufacturing costs without affecting the electrical isolation between the DC power supply and the load.

Description

Technical Field

[0001] This application belongs to the field of power supply technology, and in particular relates to a DC power supply and a hydrogen production system. Background Technology

[0002] In DC power supply systems, switching devices are usually installed at the power output terminal. These switching devices can control the on / off state of the circuit and achieve electrical isolation between the power supply and the load.

[0003] However, the large size of the switching devices makes it difficult to miniaturize the entire power supply module. In addition, the high price of the switching devices increases the cost of the DC power supply system. Utility Model Content

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a DC power supply and a hydrogen production system that can save installation space for the DC power supply and reduce manufacturing costs without affecting the electrical isolation between the DC power supply and the load.

[0005] In a first aspect, this application provides a DC power supply, which includes:

[0006] A power conversion circuit, wherein the positive output terminal of the power conversion circuit is connected to the positive output terminal of the DC power supply, and the negative output terminal of the power conversion circuit is connected to the negative output terminal of the DC power supply.

[0007] A switching element is disposed between the positive output terminal of the power conversion circuit and the positive output terminal of the DC power supply.

[0008] A unidirectional conducting element is disposed between the negative output terminal of the power conversion circuit and the negative output terminal of the DC power supply, and the conducting direction of the unidirectional conducting element is from the negative output terminal of the DC power supply to the negative output terminal of the power conversion circuit.

[0009] According to the DC power supply provided in the application embodiment, the switching element at the negative output terminal of the power conversion circuit is optimized into a unidirectional conducting element. When the switching element at the positive output terminal of the power conversion circuit is turned off, the unidirectional conducting element can provide a break point between the power conversion circuit and the load without affecting the electrical isolation between the DC power supply and the load. Furthermore, the unidirectional conducting element has a smaller size and lower cost, which can save the installation space of the DC power supply and reduce manufacturing costs.

[0010] According to one embodiment of this application, there are multiple power conversion circuits, and at least two of the power conversion circuits have a corresponding unidirectional conducting element at their negative output terminals. The negative output terminals of the at least two power conversion circuits are connected in parallel to the negative output terminal of the DC power supply through the corresponding unidirectional conducting elements.

[0011] According to one embodiment of this application, there are multiple power conversion circuits, and the negative output terminals of at least two of the power conversion circuits are connected in parallel and then connected in parallel to the negative output terminal of the DC power supply through one of the unidirectional conducting elements.

[0012] According to one embodiment of this application, there are multiple power conversion circuits, and the switching element includes at least two disconnecting units. Each of the at least two power conversion circuits has a corresponding disconnecting unit at its positive output terminal, and the positive output terminals of the at least two power conversion circuits are connected in parallel to the positive output terminal of the DC power supply through the corresponding disconnecting units.

[0013] According to one embodiment of this application, the unidirectional conducting element is a thyristor or a switching transistor.

[0014] According to one embodiment of this application, the power conversion circuit includes a DC-DC conversion circuit, which is a buck circuit, a boost circuit, or a buck-boost circuit.

[0015] According to one embodiment of this application, the power conversion circuit includes a DC-DC converter circuit and a rectifier circuit, wherein the output terminal of the rectifier circuit is connected to the input terminal of the DC-DC converter circuit; the DC-DC converter circuit is a buck converter circuit, a boost converter circuit, or a buck-boost converter circuit.

[0016] According to one embodiment of this application, there are multiple power conversion circuits, and the input terminals of at least two of the power conversion circuits' DC-DC conversion circuits are connected in parallel to an AC power source through corresponding rectifier circuits.

[0017] According to one embodiment of this application, there are multiple power conversion circuits, at least two of the power conversion circuits share the rectifier circuit, and the input terminals of the DC-DC conversion circuits in the at least two power conversion circuits are connected in parallel to the AC power supply through the shared rectifier circuit.

[0018] Secondly, this application provides a hydrogen production system, which includes:

[0019] Hydrogen production unit;

[0020] As described in the first aspect above, the DC power supply is connected to the hydrogen production unit and is used to provide DC power to the hydrogen production unit.

[0021] According to the hydrogen production system provided in the application embodiment, the switching element at the negative output terminal of the power conversion circuit in the DC power supply of the hydrogen production system is optimized into a unidirectional conducting element. When the switching element at the positive output terminal of the power conversion circuit is turned off, the unidirectional conducting element can provide a break point between the power conversion circuit and the load without affecting the electrical isolation between the DC power supply and the load. Furthermore, the unidirectional conducting element has a smaller size and lower cost, which can save the installation space of the DC power supply and reduce manufacturing costs.

[0022] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0023] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0024] Figure 1 This is a schematic diagram of the structure of a DC power supply system in related technologies;

[0025] Figure 2 This is one of the structural schematic diagrams of the DC power supply provided in the embodiments of this application;

[0026] Figure 3 This is a second schematic diagram of the structure of the DC power supply provided in the embodiments of this application;

[0027] Figure 4 This is the third schematic diagram of the DC power supply provided in the embodiments of this application;

[0028] Figure 5 This is the fourth schematic diagram of the DC power supply provided in the embodiments of this application;

[0029] Figure 6 This is the fifth schematic diagram of the DC power supply provided in the embodiments of this application;

[0030] Figure 7 This is a schematic diagram of the hydrogen production system provided in the embodiments of this application.

[0031] Figure label:

[0032] DC power supply 100, power conversion circuit 110, DC-DC conversion circuit 111, rectifier circuit 112, switching element 120, disconnecting unit 121, unidirectional conducting element 130, positive output terminal of power conversion circuit 140, negative output terminal of power conversion circuit 150, positive output terminal of DC power supply 160, negative output terminal of DC power supply 170, circuit breaker 180.

[0033] Hydrogen production system 200, hydrogen production unit 210. Detailed Implementation

[0034] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0035] The DC power supply and hydrogen production system provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0036] like Figure 2 As shown, the DC power supply 100 includes: a power conversion circuit 110, a switching element 120, and a unidirectional conducting element 130.

[0037] The power conversion circuit 110 is a circuit that converts one type of electrical energy into another. In some embodiments, the power conversion circuit 110 includes a DC-DC converter 111; or, the power conversion circuit 110 includes a rectifier circuit 112 and a DC-DC converter 111, with the output terminal of the rectifier circuit 112 connected to the input terminal of the DC-DC converter 111. The rectifier circuit 112 can convert alternating current into direct current, and the DC-DC converter 111 can convert one type of direct current into another. The DC-DC converter includes, but is not limited to, buck circuits, boost circuits, and buck-boost circuits.

[0038] The switching element 120 has two states: on and off. It can be switched between these two states via a mechanical structure or electrical signal, thereby controlling the flow of current and achieving electrical isolation in the circuit structure. In practical applications, the switching element 120 can be a disconnect (QS) switch or a load switch.

[0039] The unidirectional conducting element 130 has the characteristics of forward current conduction and reverse current cutoff, allowing current to flow in a single direction. In practical applications, the unidirectional conducting element 130 can be a thyristor or a switching transistor, etc.

[0040] In this embodiment, such as Figure 2 As shown, the positive output terminal 140 of the power conversion circuit is connected to the positive output terminal 160 of the DC power supply, and the negative output terminal 150 of the power conversion circuit is connected to the negative output terminal 170 of the DC power supply.

[0041] The switching element 120 is disposed between the positive output terminal 140 of the power conversion circuit and the positive output terminal 160 of the DC power supply. By disconnecting the switching element 120, electrical isolation between the positive output terminal 140 of the power conversion circuit and the positive output terminal 160 of the DC power supply can be achieved.

[0042] A unidirectional conducting element 130 is disposed between the negative output terminal 150 of the power conversion circuit and the negative output terminal 170 of the DC power supply. The conducting direction of the unidirectional conducting element 130 is from the negative output terminal 170 of the DC power supply to the negative output terminal 150 of the power conversion circuit.

[0043] With a load connected to the positive output terminal 160 and negative output terminal 170 of the DC power supply, and the switching element 120 in the ON state, the current in the circuit flows from the positive output terminal 140 of the power conversion circuit through the positive output terminal 160 of the DC power supply to the load, and then from the load through the negative output terminal 170 of the DC power supply back to the negative output terminal 150 of the power conversion circuit. This is the same as the conduction direction of the unidirectional conducting element 130, so the current can form a loop, and the DC power supply 100 works normally.

[0044] When a load is connected to the positive output terminal 160 and the negative output terminal 170 of the DC power supply, but the switching element 120 is in the open state, the current cannot flow from the positive output terminal 140 of the power conversion circuit to the load. The unidirectional conducting element 130 conducts from the negative output terminal 170 of the DC power supply to the negative output terminal 150 of the power conversion circuit, and the current also cannot flow from the negative output terminal 150 of the power conversion circuit to the load. The current cannot form a loop, and the DC power supply 100 is electrically isolated from the load.

[0045] If the negative output terminal 150 of the power conversion circuit is not equipped with a unidirectional conducting element 130, but is directly connected to the load through the negative output terminal 170 of the DC power supply, complete electrical isolation between the DC power supply 100 and the load cannot be achieved when the DC power supply 100 is in standby or under maintenance, which will increase the risk of use and the difficulty of maintenance. In practical applications, the load can be a hydrogen electrolyzer.

[0046] In this embodiment, a switching element 120 is provided at the positive output terminal 140 of the power conversion circuit, and a unidirectional conducting element 130 is provided at the negative output terminal 150 of the power conversion circuit. This can provide a disconnection point between the negative output terminal 150 of the power conversion circuit and the load, thereby achieving electrical isolation between the entire DC power supply 100 and the load by controlling the on / off state of the switching element 120.

[0047] In related technologies, such as Figure 1 As shown, a DC power supply system typically includes a power conversion circuit. This circuit has two output terminals with opposite polarities: a positive output terminal and a negative output terminal. By placing switching devices at both the positive and negative output terminals of the power conversion circuit, electrical isolation between the DC power supply and the load can be achieved. Figure 1 QS1 and QS2 are switching devices. The power conversion circuit includes a rectifier circuit and a BUCK circuit. QF is a circuit breaker located at the input of the power conversion circuit.

[0048] However, switching devices are often larger and more expensive. In particular, in power supplies with a multi-parallel structure, there are multiple power conversion circuits connected in parallel. Each power conversion circuit requires a switching device at both its positive and negative output terminals, which further increases the size and cost of the DC power supply system.

[0049] In this embodiment, a switching element 120 is provided at the positive output terminal 140 of the power conversion circuit, and a smaller and lower-cost unidirectional conducting element 130 is used to replace the switching element 120 at the negative output terminal 150 of the power conversion circuit 110. Without affecting the electrical isolation between the DC power supply 100 and the load, the number and size of the switching element 120 in the DC power supply 100 can be reduced, thereby saving installation space and reducing manufacturing costs.

[0050] According to the DC power supply 100 provided in the application embodiment, the switching element 120 of the negative output terminal 150 of the power conversion circuit is optimized into a unidirectional conducting element 130. When the switching element 120 of the positive output terminal 140 of the power conversion circuit is turned off, the unidirectional conducting element 130 can provide a break point between the power conversion circuit 110 and the load without affecting the electrical isolation between the DC power supply 100 and the load. Furthermore, the unidirectional conducting element 130 has a smaller size and lower cost, which can save the installation space of the DC power supply 100 and reduce the manufacturing cost.

[0051] The following sections will describe in detail the configuration scheme of the unidirectional conduction element 130 in the embodiments of this application from two different implementation perspectives.

[0052] 1. One unidirectional conducting element 130 is connected to one power conversion circuit 110.

[0053] In some embodiments, such as Figure 3 As shown, there are multiple power conversion circuits 110. At least two power conversion circuits 110 have a corresponding unidirectional conducting element 130 at their negative output terminal 150. The negative output terminals 150 of the at least two power conversion circuits are connected in parallel to the negative output terminal 170 of the DC power supply through the corresponding unidirectional conducting elements 130. That is, the negative output terminals 150 of at least two power conversion circuits are connected in parallel, and each power conversion circuit 110 has a corresponding unidirectional conducting element 130.

[0054] In this embodiment, the DC power supply 100 can adopt a multi-machine parallel circuit structure, including at least two power conversion circuits 110. Each power conversion circuit 110 has a positive output terminal and a negative output terminal. The positive output terminals 140 of all power conversion circuits are connected in parallel to the positive output terminal 160 of the DC power supply, and the negative output terminals 150 of all power conversion circuits are connected in parallel to the negative output terminal 170 of the DC power supply.

[0055] In this embodiment, the unidirectional conducting element 130 and the negative output terminal 150 of the power conversion circuit are in a one-to-one correspondence. Each unidirectional conducting element 130 is disposed between the negative output terminal 150 of the power conversion circuit and the negative output terminal 170 of the DC power supply.

[0056] At this time, a switching element 120 is provided at the positive output terminal 140 of the power conversion circuit, and a unidirectional conducting element 130 is provided at the negative output terminal 150 of the power conversion circuit, thereby achieving complete isolation between the DC power supply 100 and the load.

[0057] In practical applications, when the DC power supply 100 needs to output current or voltage, all the switching elements 120 can be closed to achieve normal power supply of the DC power supply 100.

[0058] When the DC power supply 100 needs to be shut down, the positive output terminal 140 of the power conversion circuit can be disconnected by the switching element 120. After the switching element 120 is disconnected, the positive output terminals 140 of all power conversion circuits are electrically isolated, and the unidirectional conducting element 130 will cut off the current from the negative output terminal 150 of the power conversion circuit to the load, thereby realizing the electrical disconnection between the DC power supply 100 and the load.

[0059] In this embodiment, the unidirectional conducting element 130 can provide a disconnection point between the negative output terminal 150 of the power conversion circuit and the load when the switching element 120 is not provided at the negative output terminal 150 of the power conversion circuit, thereby achieving complete isolation between the DC power supply 100 and the load, reducing the risk of using the DC power supply 100 and the difficulty of maintenance.

[0060] Furthermore, the negative output terminal 150 of different power conversion circuits can be individually controlled by the unidirectional conduction element 130. When the negative output terminal 150 of some power conversion circuits is short-circuited to ground, other power conversion circuits 110 can still operate normally.

[0061] 2. One unidirectional conducting element 130 connects to multiple power conversion circuits 110.

[0062] In some embodiments, such as Figure 4 As shown, there are multiple power conversion circuits 110, and the negative output terminals 150 of at least two power conversion circuits are connected in parallel and then connected in parallel to the negative output terminal 170 of the DC power supply through a unidirectional conducting element 130. That is, a unidirectional conducting element 130 is provided between the at least two parallel power conversion circuits 110 and the negative output terminal 170 of the DC power supply.

[0063] In this embodiment, the DC power supply 100 can adopt a multi-machine parallel circuit structure, including at least two power conversion circuits 110. Each power conversion circuit 110 has a positive output terminal and a negative output terminal. The positive output terminals 140 of all power conversion circuits are connected in parallel to the positive output terminal 160 of the DC power supply, and the negative output terminals 150 of all power conversion circuits are connected in parallel to the negative output terminal 170 of the DC power supply.

[0064] In this embodiment, the DC power supply 100 is provided with only one unidirectional conducting element 130, which is located at the negative output terminal 170 of the DC power supply. The negative output terminals 150 of all power conversion circuits are connected to the unidirectional conducting element 130.

[0065] At this time, a switching element 120 is provided on the positive output terminal 140 of the power conversion circuit, and a unidirectional conducting element 130 is provided on the negative output terminal 170 of the DC power supply, thereby achieving complete isolation between the DC power supply 100 and the load.

[0066] In practical applications, when the DC power supply 100 needs to output current or voltage, all the switching elements 120 can be closed to achieve normal power supply of the DC power supply 100.

[0067] When the DC power supply 100 needs to be shut down, the positive output terminal 140 of the power conversion circuit can be disconnected by the switching element 120. After the switching element 120 is disconnected, the positive output terminals 140 of all power conversion circuits are electrically isolated, and the unidirectional conducting element 130 will cut off the current from the negative output terminal 170 of the DC power supply to the load, thereby realizing the electrical disconnection between the DC power supply 100 and the load.

[0068] In this embodiment, the unidirectional conducting element 130 can provide a disconnection point between the negative output terminal 150 of the power conversion circuit and the load when the switching element 120 is not provided at the negative output terminal 150 of the power conversion circuit, thereby achieving complete isolation between the DC power supply 100 and the load, reducing the risk of using the DC power supply 100 and the difficulty of maintenance.

[0069] Furthermore, the negative output terminals 150 of different power conversion circuits can be uniformly controlled by a single unidirectional conducting element 130, and the negative output terminals 150 of different power conversion circuits can be integrated together for easy parallel connection, thereby reducing the size of the DC power supply 100.

[0070] In some embodiments, such as Figure 3 and Figure 4 As shown, there are multiple power conversion circuits 110, and the switching element 120 includes at least two disconnecting units 121. Each power conversion circuit 110 has a corresponding disconnecting unit 121 at its positive output terminal 140. The positive output terminals 140 of the at least two power conversion circuits are connected in parallel to the positive output terminal 160 of the DC power supply through the corresponding disconnecting units 121.

[0071] In this embodiment, the DC power supply 100 can adopt a multi-machine parallel circuit structure, including at least two power conversion circuits 110. Each power conversion circuit 110 has a positive output terminal 140 and a negative output terminal 150. The positive output terminals 140 of all power conversion circuits are connected in parallel to the positive output terminal 160 of the DC power supply, and the negative output terminals 150 of all power conversion circuits are connected in parallel to the negative output terminal 170 of the DC power supply.

[0072] In one implementation, the DC power supply 100 includes multiple power conversion circuits 110 and a switching element 120. All power conversion circuits 110 are connected in parallel, and the switching element 120 includes multiple disconnecting units 121. The disconnecting units 121 are disposed one-to-one between the positive output terminal 140 of the power conversion circuit and the positive output terminal 160 of the DC power supply.

[0073] In another implementation, the DC power supply 100 includes multiple power conversion circuits 110, which are divided into multiple groups. Each group corresponds to a switching element 120. All power conversion circuits 110 are connected in parallel. Each switching element 120 includes multiple disconnecting units 121. The disconnecting units 121 of each switching element 120 are respectively disposed between the positive output terminal 140 of the corresponding group of power conversion circuits and the positive output terminal 160 of the DC power supply.

[0074] For example, such as Figure 3 and Figure 4As shown, the DC power supply 100 includes four parallel power conversion circuits 110, and the positive output terminals 140 of the four power conversion circuits ( Figure 3 and Figure 4 The + terminal of the four power conversion circuits is connected in parallel to the positive output terminal 160 of the DC power supply; the negative output terminal 150 of the four power conversion circuits is connected in parallel to the positive output terminal 160 of the DC power supply. Figure 3 and Figure 4 The - end of the circuit is connected in parallel to the negative output terminal 170 of the DC power supply. Every two power conversion circuits 110 form a group, and each switching element 120 includes two breaking units 121. The breaking units 121 of each switching element 120 are respectively arranged between the positive output terminal 140 of the corresponding power conversion circuit and the positive output terminal 160 of the DC power supply. That is, every two power conversion circuits 110 share one switching element 120.

[0075] In this embodiment, by connecting at least two power conversion circuits 110 in parallel, the output current capabilities of each power conversion circuit 110 can be superimposed to achieve higher power output.

[0076] In this embodiment, the switching element 120 includes at least two breaking units 121, which are disposed one-to-one between the positive output terminal 140 of the power conversion circuit and the positive output terminal 160 of the DC power supply.

[0077] In this implementation, by disconnecting the disconnecting unit 121 located at the positive output terminal 140 of the power conversion circuit, electrical isolation between the positive output terminal 140 of the power conversion circuit and the positive output terminal 160 of the DC power supply can be achieved, preventing the current in the DC power supply 100 from continuing to be transmitted to the load, and reducing the probability of related circuit devices being broken down or damaged due to incomplete electrical isolation.

[0078] In practical applications, the switching element 120 can be a double-pole switch, and each switching element 120 has two disconnecting units 121 for achieving electrical isolation in the circuit structure.

[0079] The following describes a specific embodiment, using a two-pole switch element 120 as an example.

[0080] like Figure 3 and Figure 4 As shown, the DC power supply 100 includes four parallel power conversion circuits 110 and two switching elements 120. Each switching element 120 includes two disconnection units 121, that is, there are a total of four disconnection units 121. These four disconnection units 121 are set at the positive output terminals 140 of the four power conversion circuits, that is, each switching element 120 controls the electrical isolation of the positive output terminals 140 of two power conversion circuits respectively.

[0081] In this embodiment, a bipolar switch with two breaking units 121 is selected as the switching element 120, and different breaking units 121 of the same switching element 120 are set at the positive output terminals 140 of different power conversion circuits. This allows the positive output terminals 140 of the two power conversion circuits to share a single switching element 120, thereby reducing the number of switching elements 120 in the DC power supply 100.

[0082] In practical applications, the switching element 120 can also be a three-pole switch, with each switching element 120 having three breaking units 121 for achieving electrical isolation in the circuit structure.

[0083] The following is a specific embodiment, using a three-pole switch as an example of switching element 120.

[0084] like Figure 5 As shown, the DC power supply 100 includes six parallel power conversion circuits 110 and two switching elements 120. Each switching element 120 includes three disconnection units 121, that is, there are a total of six disconnection units 121. These six disconnection units 121 are set at the positive output terminals 140 of the six power conversion circuits, that is, each switching element 120 controls the electrical isolation of the positive output terminals 140 of the three power conversion circuits respectively.

[0085] In this embodiment, a three-pole switch with three breaking units 121 is selected as the switching element 120, and different breaking units 121 of the same switching element 120 are set at the positive output terminals 140 of different power conversion circuits. This allows the positive output terminals 140 of the three power conversion circuits to share a single switching element 120, thereby reducing the number of switching elements 120 in the DC power supply 100.

[0086] It should be noted that in a hydrogen production power supply with multiple parallel power conversion circuits 110, the relevant technology configures a bipolar switch at the output terminal of each power conversion circuit. The two poles of each bipolar switch control the on / off state of the positive and negative output terminals of the corresponding power conversion circuit, thereby achieving electrical isolation between the hydrogen production power supply and the load. As the number of parallel power conversion circuits increases, the number of switches required also increases accordingly.

[0087] In this embodiment, by replacing the disconnecting unit 121 of the negative output terminal 150 of the power conversion circuit with a unidirectional conducting element 130, and then setting different disconnecting units 121 of the same switching element 120 at the positive output terminals 140 of different power conversion circuits, it is possible to enable two or more power conversion circuits 110 to share a single switching element 120, thereby reducing the number of switching elements 120 used, lowering material costs, and reducing the size and weight of the DC power supply 100, which is beneficial for the equipment layout, transportation, installation, and maintenance of the power supply system.

[0088] In some embodiments, the unidirectional conducting element 130 is a unidirectional controllable conducting element, wherein the conducting direction of the unidirectional controllable conducting element is controllable, and the cut-off direction is controllable or uncontrollable.

[0089] In some embodiments, the unidirectional conducting element 130 is a thyristor.

[0090] Understandably, a thyristor is a semiconductor switching device that can conduct electricity through a turn-on signal and will only turn off when the current in the circuit drops below the latching current or a reverse voltage is applied.

[0091] In this embodiment, the thyristor is turned on from the load to the negative output terminal 150 of the power conversion circuit.

[0092] In practical applications, when the DC power supply 100 needs to output current or voltage, all the switching elements 120 can be closed and a conduction signal can be sent to the thyristor to realize the normal power supply of the DC power supply 100.

[0093] When the DC power supply 100 needs to be shut down, the positive output terminal 140 of the power conversion circuit can be disconnected by the switching element 120. When the switching element 120 is disconnected, the positive output terminals 140 of all power conversion circuits are electrically isolated. At this time, the current in the circuit will drop to 0, which is less than the latching current of the thyristor. The thyristor will then disconnect, thereby achieving electrical disconnection between the DC power supply 100 and the load.

[0094] In this embodiment, a breakpoint can be provided between the negative output terminal 150 of the power conversion circuit and the load by means of a thyristor. The size and cost of the thyristor are lower than those of the switching element 120, which can save installation space and manufacturing costs of the DC power supply 100.

[0095] In some embodiments, the unidirectional conducting element 130 is a switching transistor.

[0096] As is understandable, a switching transistor is a semiconductor switching device that can switch between on and off states by controlling the voltage across its emitter junction.

[0097] In this embodiment, the switching transistor is turned on from the load to the negative output terminal 150 of the power conversion circuit.

[0098] In actual operation, when the DC power supply 100 needs to output current or voltage, all the switching elements 120 can be closed, and the voltage of the emitter junction of the switching transistor can be adjusted to a high level to make the switching transistor conduct, thereby enabling the DC power supply 100 to supply power normally.

[0099] When the DC power supply 100 needs to be stopped, the positive output terminal 140 of the power conversion circuit can be disconnected by the switching element 120, and the voltage of the emitter junction of the switching transistor can be adjusted to a low level, so that the switching transistor is in the cut-off state, thereby realizing the electrical disconnection between the DC power supply 100 and the load.

[0100] In this embodiment, a switching transistor can provide a breakpoint between the negative output terminal 150 of the power conversion circuit and the load. The switching transistor is smaller and less expensive than the switching element 120, which can save installation space and manufacturing costs of the DC power supply 100.

[0101] In some embodiments, the power conversion circuit 110 includes a DC-DC converter 111, which is a buck converter. The buck converter can reduce the input voltage to the desired output voltage.

[0102] In some embodiments, the power conversion circuit 110 includes a DC-DC converter 111, which is a boost converter. The boost converter can increase the input voltage to the desired output voltage.

[0103] In some embodiments, the power conversion circuit 110 includes a DC-DC converter 111, which is a buck-boost circuit. The buck-boost circuit has both boost and buck functions and can flexibly output DC power higher or lower than the input voltage.

[0104] In some embodiments, such as Figure 4 and Figure 6 As shown, the power conversion circuit 110 includes a DC-DC converter circuit 111 and a rectifier circuit 112. The output terminal of the rectifier circuit 112 is connected to the input terminal of the DC-DC converter circuit. The DC-DC converter circuit 111 is a buck converter, a boost converter, or a buck-boost converter, as described above. The rectifier circuit 112 can convert AC power into DC power.

[0105] In practical applications, the rectifier circuit 112 can be a PWM rectifier.

[0106] In this embodiment, the input terminal of the rectifier circuit is connected to the AC power supply, and the output terminal of the rectifier circuit is connected to the input terminal of all DC-DC converter circuits 111, for providing DC input to the DC-DC converter circuits 111.

[0107] In some embodiments, there are multiple power conversion circuits 110, and the input terminals of DC-DC conversion circuits 111 in at least two power conversion circuits 110 are connected in parallel to an AC power source through corresponding rectifier circuits 112.

[0108] For example, such as Figure 4 As shown, the DC power supply 100 includes four DC-DC conversion circuits 111, and the input terminals of the four DC-DC conversion circuits 111 are connected to four rectifier circuits 112 in a one-to-one correspondence. Four circuit breakers 180 are also provided between the AC power supply and these four rectifier circuits 112.

[0109] In practical applications, when the DC power supply 100 is connected to the AC power supply and starts working, all circuit breakers 180 can be adjusted to the connected state. At this time, the AC power supply will output current to all rectifier circuits 112. Each rectifier circuit 112 converts the input AC current into DC current and outputs it to the DC-DC converter circuit 111 connected to it.

[0110] In this embodiment, by providing a rectifier circuit 112 in each DC-DC converter circuit 111 of the DC power supply 100, the AC current input from the AC power supply can be converted into DC current, and each rectifier circuit 112 provides input current to the corresponding DC-DC converter circuit 111.

[0111] In addition, a circuit breaker 180 is provided between the AC power supply and each rectifier circuit 112, which can realize individual control of the start and stop of each power conversion circuit 110 in the DC power supply 100.

[0112] In some embodiments, there are multiple power conversion circuits 110, with at least two power conversion circuits 110 sharing a rectifier circuit 112, and the input terminals of the DC-DC conversion circuits 111 in the at least two power conversion circuits 110 being connected in parallel to an AC power source through the shared rectifier circuit 112.

[0113] For example, such as Figure 6 As shown, the DC power supply 100 is equipped with a rectifier circuit 112 and a circuit breaker 180. The input terminal of the rectifier circuit 112 is connected to the circuit breaker 180, and the output terminal of the rectifier circuit 112 is connected to the input terminals of the four DC-DC converter circuits 111 in the DC power supply 100.

[0114] In practical applications, when the DC power supply 100 is connected to the AC power supply and starts working, the circuit breaker 180 can be adjusted to the connected state. At this time, the AC power supply will output current to the rectifier circuit 112. The rectifier circuit 112 converts the input AC current into DC current and outputs it to each DC-DC converter circuit 111 in the DC power supply 100.

[0115] In this embodiment, a common rectifier circuit 112 is provided at the input terminals of at least two DC-DC converter circuits 111, which can convert the AC current input by the AC power supply into DC current, and provide input current to multiple DC-DC converter circuits 111 simultaneously through one rectifier circuit 112.

[0116] In addition, a circuit breaker 180 is provided between the AC power supply and the rectifier circuit 112. The arrangement of sharing the rectifier circuit 112 can reduce the number of circuit breakers 180, and control the input current of the entire DC power supply 100 with fewer circuit breakers 180, thereby reducing the size of the DC power supply 100.

[0117] This application also provides a hydrogen production system 200, such as... Figure 7 As shown, the system includes a hydrogen production unit 210 and the aforementioned DC power supply 100.

[0118] The DC power supply 100 is connected to the hydrogen production unit 210 and is used to provide DC power to the hydrogen production unit 210.

[0119] In this embodiment, the hydrogen production unit 210 can be a hydrogen production electrolyzer, including but not limited to an alkaline electrolyzer (AWE / ALK), a proton exchange membrane electrolyzer (PEM), a solid oxide electrolyzer (SOEC), and an anion exchange membrane electrolyzer (AEM).

[0120] According to the hydrogen production system 200 provided in the application embodiment, the DC power supply 100 in the hydrogen production system 200 optimizes the switching element 120 of the negative output terminal 150 of the power conversion circuit into a unidirectional conducting element 130. When the switching element 120 of the positive output terminal of the power conversion circuit 110 is turned off, the unidirectional conducting element 130 can provide a break point between the power conversion circuit 110 and the load without affecting the electrical isolation between the DC power supply 100 and the load. Furthermore, the unidirectional conducting element 130 has a smaller size and lower cost, which can save the installation space of the DC power supply 100 and reduce the manufacturing cost of the DC power supply 100 and the hydrogen production system 200.

[0121] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0122] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0123] In the description of this application, "multiple" means two or more.

[0124] In the description of this application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them.

[0125] In the description of this application, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0126] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0127] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A DC power supply, characterized in that, include: A power conversion circuit, wherein the positive output terminal of the power conversion circuit is connected to the positive output terminal of the DC power supply, and the negative output terminal of the power conversion circuit is connected to the negative output terminal of the DC power supply. A switching element is disposed between the positive output terminal of the power conversion circuit and the positive output terminal of the DC power supply. A unidirectional conducting element is disposed between the negative output terminal of the power conversion circuit and the negative output terminal of the DC power supply, and the conducting direction of the unidirectional conducting element is from the negative output terminal of the DC power supply to the negative output terminal of the power conversion circuit.

2. The DC power supply according to claim 1, characterized in that, The power conversion circuit is a plurality of circuits, and at least two of the power conversion circuits have a corresponding unidirectional conducting element at their negative output terminals. The negative output terminals of the at least two power conversion circuits are connected in parallel to the negative output terminal of the DC power supply through the corresponding unidirectional conducting elements.

3. The DC power supply according to claim 1, characterized in that, The power conversion circuit is a plurality of circuits, and the negative output terminals of at least two power conversion circuits are connected in parallel and then connected in parallel to the negative output terminal of the DC power supply through a unidirectional conducting element.

4. The DC power supply according to any one of claims 1-3, characterized in that, The power conversion circuits are multiple, and the switching element includes at least two disconnecting units. Each of the power conversion circuits has a corresponding disconnecting unit at its positive output terminal. The positive output terminals of the at least two power conversion circuits are connected in parallel to the positive output terminal of the DC power supply through the corresponding disconnecting units.

5. The DC power supply according to any one of claims 1-3, characterized in that, The unidirectional conducting element is a thyristor or a switching transistor.

6. The DC power supply according to any one of claims 1-3, characterized in that, The power conversion circuit includes a DC-DC conversion circuit, which is a buck circuit, a boost circuit, or a buck-boost circuit.

7. The DC power supply according to any one of claims 1-3, characterized in that, The power conversion circuit includes a DC-DC converter circuit and a rectifier circuit. The output terminal of the rectifier circuit is connected to the input terminal of the DC-DC converter circuit. The DC-DC converter circuit is a buck converter circuit, a boost converter circuit, or a buck-boost converter circuit.

8. The DC power supply according to claim 7, characterized in that, The power conversion circuits are multiple, and the input terminals of at least two of the power conversion circuits' DC-DC conversion circuits are connected in parallel to the AC power supply through the corresponding rectifier circuits.

9. The DC power supply according to claim 7, characterized in that, There are multiple power conversion circuits, with at least two power conversion circuits sharing the rectifier circuit. The input terminals of the DC-DC conversion circuits in at least two power conversion circuits are connected in parallel to the AC power supply through the shared rectifier circuit.

10. A hydrogen production system, characterized in that, include: Hydrogen production unit; The DC power supply according to any one of claims 1-9, wherein the DC power supply is connected to the hydrogen production unit, and the DC power supply is used to provide DC power to the hydrogen production unit.

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