A highly reliable safety relay applicable to a hydrogen liquefaction device

Abstract

The present invention relates to the field of relay technology, and in particular to a high-reliability safety relay suitable for a hydrogen liquefaction device, the relay comprising: an enable control circuit, at least one input control circuit, at least one output control circuit and a control chip circuit; the enable control circuit comprises an enable main loop, in which an enable interface is provided; the input control circuit comprises an input control main loop, in which an input interface for connecting an interlocking device signal is provided; the output control circuit comprises an output control main loop; the enable main loop, the input control main loop and the control chip circuit all control the connection of the output control main loop. The relay of the present invention can provide a highly reliable protection function.

Description

Technical Field

[0001] The present invention relates to the technical field of relays, and in particular to a high-reliability safety relay suitable for a hydrogen liquefaction device. Background Art

[0002] Hydrogen liquefaction production systems place extremely high demands on equipment stability. Safety protection devices, as the most crucial component of safety protection, must not fail or mis-trigger. Therefore, safety interlock devices and signals, such as the turbine inlet valve emergency control, turbine control system emergency shutdown signal, main power supply status signal, and equipment vibration signal, must be connected to a highly reliable safety interlock control device.

[0003] Existing safety interlock control devices have the following problems: 1. Output channels are directly controlled by processing chips or controllers, which poses a certain risk of failure; 2. Channels and outputs are designed separately in circuit design, so a channel failure can cause device failure; 3. Device status cannot be checked in a timely manner when a device fails, resulting in poor control reliability. Therefore, a highly reliable and stable safety interlock control device is urgently needed. Summary of the Invention

[0004] In order to solve the above technical problems, an object of the present invention is to provide a high-reliability safety relay suitable for a hydrogen liquefaction device.

[0005] The present invention provides a high-reliability safety relay suitable for a hydrogen liquefaction device, the relay comprising: an enable control circuit, at least one input control circuit, at least one output control circuit and a control chip circuit; the enable control circuit comprises an enable main loop, in which an enable interface is provided; the input control circuit comprises an input control main loop, in which an input interface for connecting an interlocking device signal is provided; the output control circuit comprises an output control main loop; the enable main loop, the input control main loop and the control chip circuit all control the connection to the output control main loop.

[0006] Furthermore, the enable control circuit, the input control circuit and the output control circuit are also provided with a diagnostic circuit for detecting the working status of the enable main circuit, the input control main circuit and the output control main circuit; the output end of the diagnostic circuit is connected to the control chip circuit.

[0007] Furthermore, the relay includes at least two redundant input control circuits, and an input interface and a group of input relay coils are arranged in series in the input control main circuit of each input control circuit, and the group of relay coils is composed of the coils of at least two input relays connected in parallel; the enable main circuit and the output control main circuit are both provided with normally open contact switches of the input relays.

[0008] Furthermore, the normally open contact switches of each group of input relays, the enabling interface and the coils of the enabling relays are sequentially arranged in series in the enabling main circuit; the normally open contact switches of each group of input relays are composed of a normally open contact switch of each input relay corresponding to a group of input relay coils in the input control main circuit of the input control circuit arranged in parallel; the enabling interface is also provided with a push button switch and a self-locking branch of the enabling relay in parallel, and the normally open contact switch of the enabling relay and the enabling circuit interface are arranged in series in the self-locking branch.

[0009] Furthermore, the relay includes at least two redundant output control circuits, wherein the at least two output control circuits include at least one immediate output control circuit and at least one delayed output control circuit.

[0010] Furthermore, a normally closed switch controlled by the control chip circuit, a normally open contact switch of the enabling relay, a group of input relay normally open contact switches and a group of instant relay coils are sequentially arranged in series in the output control main loop of each instant output control circuit. The group of input relay normally open contact switches is composed of a normally open contact switch of each input relay corresponding to a group of input relay coils in the input control main loop of one input control circuit being arranged in parallel, and the group of instant relay coils is composed of the coils of at least two instant relays connected in parallel.

[0011] Furthermore, a normally closed switch controlled by the control chip circuit, a normally open contact switch of the enabling relay, a group of input relay normally open contact switches and a group of delay relay coils are sequentially arranged in series in the output control main circuit of each of the delayed output control circuits. The group of input relay normally open contact switches is composed of a normally open contact switch of each input relay corresponding to a group of input relay coils in the input control main circuit of one of the input control circuits being arranged in parallel, and the group of delay relay coils is composed of the coils of at least two delay relays connected in parallel.

[0012] Furthermore, the control chip circuit includes at least two redundantly configured MCU chips and at least two output control drive circuits. Each of the MCU chips samples and is connected to each of the diagnostic circuits. Each of the MCU chips controls and is connected to each of the output control drive circuits. Each of the output control drive circuits is provided with a power supply control relay coil for controlling a normally closed switch in the output control main circuit of one of the output control circuits.

[0013] Furthermore, each output control drive circuit includes a transistor; the base of the transistor is connected to the input end of the output control drive circuit through a resistor, the collector of the transistor is connected to the power supply through a resistor, and the collector is also grounded through two diode branches, one diode branch is provided with a diode in series, and the other diode branch is provided with a diode and a power supply control relay coil in series.

[0014] Furthermore, the diagnostic circuit is composed of a resistor, a diode and an optocoupler switch, the primary side of the optocoupler switch is connected to the input end of the diagnostic circuit through a series resistor and a diode, and the secondary side of the optocoupler switch is connected to the output end of the diagnostic circuit.

[0015] The present invention has the following beneficial effects: the relay provided by the present invention includes: an enable control circuit, at least one input control circuit, at least one output control circuit and a control chip circuit; the enable control circuit includes an enable main circuit, in which an enable interface is provided; the input control circuit includes an input control main circuit, in which an input interface for connecting an interlocking device signal is provided; the output control circuit includes an output control main circuit; the enable main circuit, the input control main circuit and the control chip circuit all control the connection to the output control main circuit. By utilizing the enable main circuit, the input control main circuit and the control chip circuit to control the connection to the output control main circuit, the present invention can effectively avoid phenomena such as timeliness and false triggering of the output control main circuit, thereby improving protection reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 This is a schematic structural diagram of a high-reliability safety relay suitable for a hydrogen liquefaction device according to an embodiment of the present invention;

[0018] Figure 2 This is an instant output circuit according to an embodiment of the present invention;

[0019] Figure 3 This is a delayed output circuit according to an embodiment of the present invention;

[0020] Figure 4 is a circuit structure diagram of a diagnostic circuit according to an embodiment of the present invention;

[0021] Figure 5 FIG. 4 is a circuit structure diagram of a drive control circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to clearly illustrate the technical features of this solution, the present invention is described in detail below through specific implementation methods in conjunction with the accompanying drawings.

[0023] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0024] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0025] As used herein, the term "including" and its variations are open-ended, i.e., "including but not limited to." The term "based on" means "based, at least in part, on." The term "one embodiment" means "at least one embodiment," the term "another embodiment" means "at least one additional embodiment," and the term "some embodiments" means "at least some embodiments." Other terms are defined in the following description.

[0026] It should be noted that the concepts of "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0027] Although operations or steps are described in a particular order in the drawings in the embodiments of the present invention, this should not be understood as requiring that these operations or steps be performed in the particular order shown or in a serial order, or that all of the operations or steps shown be performed to obtain a desired result. In the embodiments of the present invention, these operations or steps may be performed serially; they may also be performed in parallel; or a portion of these operations or steps may be performed.

[0028] At the same time, it is understood that the data involved in the technical solutions of the present invention (including but not limited to the data itself, the acquisition or use of the data) shall comply with the requirements of relevant laws, regulations and relevant provisions. Unless otherwise defined, all technical and scientific terms used in this invention have the same meanings as those commonly understood by those skilled in the art to which this invention belongs, and all parameters or indicators in the formulas involved in this invention are normalized values to eliminate the influence of dimensions.

[0029] To address the poor protection of existing relays, embodiments of the present invention provide a high-reliability safety relay suitable for hydrogen liquefaction equipment. Firstly, this relay enhances safety and reliability through design redundancy. Specifically, it utilizes a dual interlock mechanism, a 1:1 component configuration, and circuit monitoring and disconnection control to improve system safety and reliability. Within the control loop, relays form an interlocking circuit, with the input channel directly interlocked to control the output channel. Simultaneously, a diagnostic circuit monitors the input and output circuit states, with the MCU chip determining whether to disconnect or enable the output. This redundant design ensures that the system remains operational even in the event of a single component failure, significantly reducing safety risks. Secondly, the relay utilizes a back-to-back design as its control core. Specifically, the back-to-back communication between the two MCU chips within the relay forms a redundant control system. Using hot standby redundancy, if the primary MCU fails, the backup MCU chip immediately takes over, ensuring the continuity and reliability of the control system. The MCU chip also cross-validates input results to determine the validity of the output. This design principle is crucial for preventing single-point failures, particularly in critical applications where no interruptions can be tolerated. Thirdly, the relay has multiple output mode circuits. Specifically, the output channel has two functional modes: immediate output and delayed output. The immediate output immediately disconnects the output after receiving the interlock signal, while the delayed output channel delays disconnection according to the set time. The immediate output is responsible for interlock disconnection scenarios with fast response, and the delayed output is responsible for devices that require delayed disconnection after the interlock is triggered. Fourthly, the relay has high integration and good thermal management. Specifically, through a highly integrated design, the components are integrated onto a PCB board, achieving a small size and flexible installation. At the same time, due to the high degree of integration, the power consumption of the equipment can be effectively reduced, which ensures that the components will not overheat even in continuous operation, thereby extending the service life and stability of the equipment.

[0030] A high-reliability safety relay suitable for a hydrogen liquefaction device provided by an embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

[0031] Figure 1 The schematic diagram of the entire module of a high-reliability safety relay suitable for a hydrogen liquefaction device provided by an embodiment of the present invention is shown, which includes all components and working circuits in the module except the output circuit. Figure 1 As shown, this high-reliability safety relay includes an enable control circuit, two input control circuits, two output control circuits, and a control chip circuit. The power supply interface of this high-reliability safety relay is powered by an external 24V DC power supply to keep the device operational. These circuits within the relay are described in detail below, along with the accompanying drawings.

[0032] like Figure 1 As shown, the enabling control circuit includes a main enabling circuit, which is serially connected in sequence with the normally open contacts of a first group of input relays and a second group of input relays controlled by two input control circuits, enabling interfaces XI0+ and XI0-, and the coil of enabling relay K1. The normally open contacts of the first group of input relays consist of the normally open contacts of input relay K2 and input relay K3 connected in parallel; the normally open contacts of the second group of input relays consist of the normally open contacts of input relay K4 and input relay K5 connected in parallel. Furthermore, a push switch S1 and a self-locking branch of enabling relay K1 are connected in parallel to enabling interfaces XI0+ and XI0-. This self-locking branch of enabling relay K1 is serially connected with the normally open contacts of enabling relay K1 and enabling circuit interfaces XI3+ and XI3-. The enable control circuit also includes an enable input control diagnostic loop. The input of this enable input control diagnostic loop is connected between the access enable interfaces XI0+ and XI0- and the enable relay K1. The output of this enable input control diagnostic loop is connected to the I5 pins of two redundantly configured MCUs A and B in a set of control chip circuits. Since the structure of this enable input control diagnostic loop will be described in detail later, it will not be repeated here.

[0033] In the above-mentioned enable control circuit, the enable interface XI0+ and XI0- can be connected to the relay's built-in button or the external pulse signal access interface, and its function is to control the input interface (two-way input) and the output interface (immediate output and delayed output) to be enabled or disconnected. When the enable interface XI0+ and XI0- are connected to the relay's built-in button, the enable main circuit is enabled by triggering the button. When the enable interface XI0+ and XI0- are connected to the external pulse signal access interface, the external pulse signal must remain on, otherwise the enable main circuit will be disconnected.

[0034] The two-way input control circuit includes a first input control circuit and a second input control circuit. The first input control circuit includes a first input control main loop, in which interlocking interfaces (i.e., input interfaces) XI1+ and XI1- are connected in series, and a first set of input relay coils, which is composed of the coil of input relay K2 and the coil of input relay K3 connected in parallel. The second input control circuit includes a second input control main loop, in which second interlocking interfaces (i.e., input interfaces) XI2+ and XI2- are connected in series, and a second set of input relay coils, which is composed of the coil of input relay K4 and the coil of input relay K5 connected in parallel. The first input control circuit also includes a first input control first diagnostic loop (i.e., the first input control diagnostic A#) and a first input control second diagnostic loop (i.e., the first input control diagnostic B#). The input end of the first input control first diagnostic loop is connected between the first interlocking interface XI1+ and XI1- and the coil of the input relay K2, and the output end of the first input control first diagnostic loop is connected to the I6 pins of two redundantly set MCU A and MCU B in a group of control chip circuits; the input end of the first input control second diagnostic loop is connected between the first interlocking interface XI1+ and XI1- and the coil of the input relay K3, and the output end of the first input control second diagnostic loop is connected to the I7 pins of two redundantly set MCU A and MCU B in a group of control chip circuits. The second input control circuit also includes a second input control first diagnostic loop (i.e., second input control diagnostic A#) and a second input control second diagnostic loop (i.e., second input control diagnostic B#). The input end of the second input control first diagnostic loop is connected between the second interlock interface (i.e., input interface) XI2+ and XI2- and the coil of input relay K4, and the output end of the second input control first diagnostic loop is connected to pin I8 of two redundantly configured MCUs A and B in a set of control chip circuits. The input end of the second input control second diagnostic loop is connected between the second interlock interface XI2+ and XI2- and the coil of input relay K5, and the output end of the second input control second diagnostic loop is connected to pin I9 of two redundantly configured MCUs A and B in a set of control chip circuits. Since the structures of the first input control first diagnostic loop and the first input control second diagnostic loop, as well as the second input control first diagnostic loop and the second input control second diagnostic loop, will be described in detail later, they will not be repeated here.

[0035] In the aforementioned two-way input control circuit, the first interlock interfaces XI1+ and XI1-, and the second interlock interfaces XI2+ and XI2-, serve as input interfaces for inputting control conditions. By connecting a disconnect signal from the external equipment to be protected to these input interfaces, the first and second input control main loops of the two-way output control circuits will be interlocked and disconnected if these input interfaces are disconnected. For example, the turbine equipment's operational protection signal, stall sensor output signal, turbine inlet valve status signal, and equipment vibration signal in the hydrogen liquefaction system must be connected to these input interfaces.

[0036] The two-way output control circuit includes an immediate output control circuit and a delayed output control circuit. The immediate output control circuit comprises a first immediate output control main circuit, in which a set of normally closed switches O1 of the power supply control relay K in the first output control drive circuit of the control chip circuit, a normally open contact switch of the enable relay K1, a first set of normally open contact switches of the input relays, and a set of immediate relay coils are sequentially arranged in series. The first set of normally open contact switches of the input relays is composed of the normally open contact switches of the input relays K2 and K3 connected in parallel, and a set of immediate relay coils is composed of the coils of the first immediate relay J1 and the second immediate relay J2 connected in parallel. The delayed output control circuit includes a delayed output control main circuit, in which a group of second normally closed switch O2 of the power supply control relay K in the second output control drive circuit of the control chip circuit, the normally open contact switch of the enable relay K1, the second group of input relay normally open contact switches and a group of delay relay coils are arranged in series in sequence; the second group of input relay normally open contact switches is composed of the normally open contact switch of the input relay K4 and the normally open contact switch of the input relay K5 connected in parallel, and a group of delay relay coils is composed of the coil of the first delay relay J3 and the coil of the second delay relay J4 connected in parallel. The instant output control circuit also includes a first instant output diagnostic loop (i.e., a first output control diagnostic A#) and a second instant output diagnostic loop (i.e., a first output control diagnostic B#). The input end of the first instant output diagnostic loop is connected between the first group of input relay normally open contact switches and the coil of the first instant relay J1, and the output end of the first instant output diagnostic loop is connected to the I1 pins of two redundantly set MCU A and MCU B in a group of control chip circuits; the input end of the second instant output diagnostic loop is connected between the first group of input relay normally open contact switches and the coil of the second instant relay J2, and the output end of the second instant output diagnostic loop is connected to the I2 pins of two redundantly set MCU A and MCU B in a group of control chip circuits. The delayed output control circuit also includes a first delayed output diagnostic circuit (i.e., a second delayed output control diagnostic A#) and a second delayed output diagnostic circuit (i.e., a second delayed output control diagnostic B#). The input end of the first delayed output diagnostic circuit is connected between the second group of input relay normally open contact switches and the coil of the first delay relay J3, and the output end of the first delayed output diagnostic circuit is connected to the I3 pins of two redundantly set MCU A and MCU B in a group of control chip circuits; the input end of the second delayed output diagnostic circuit is connected between the second group of input relay normally open contact switches and the coil of the second delay relay J4, and the output end of the second delayed output diagnostic circuit is connected to the I4 pins of two redundantly set MCU A and MCU B in a group of control chip circuits.Since the structures of the first immediate output diagnostic circuit, the second immediate output diagnostic circuit, the first delayed output diagnostic circuit, and the second delayed output diagnostic circuit will be described in detail later, they will not be described in detail here.

[0037] In the above-mentioned two-way output control circuit, after the interlock is calculated and verified by the MCU chip in a group of control chip circuits through the input interface, the immediate output control circuit and the delayed output control circuit will perform a disconnection operation to disconnect the equipment that needs to be protected in a timely or delayed manner. Immediate output: For example, the shut-off valve of the turbine inlet valve in the hydrogen liquefaction system needs to be connected to the immediate output. When the hydrogen liquefaction device fails or an emergency occurs, the immediate output will immediately output a signal to cut off the turbine inlet valve, thereby protecting the turbine device from damage. Delayed output: For example, the bearing gas supply valve in the hydrogen liquefaction system needs to be connected to the delayed output. When the hydrogen liquefaction device fails or an emergency occurs, the delayed output will wait until the set time is reached before outputting the shut-off signal, so that the bearing gas supply valve can continue to supply gas until the equipment is completely shut down and then disconnected, thereby protecting the equipment from damage.

[0038] A control chip circuit includes two redundant MCU chips, MCU A and MCU B, a communication processing chip, and two output control drive circuits. The communication processing chip is specifically a 485 communication processing chip. The two output control drive circuits include a first output control drive circuit and a second output control drive circuit, which are respectively used to control the first normally closed switch O1 in the immediate output control circuit and the second normally closed switch O2 in the delayed output control circuit. Pin I1 of MCU A and MCU B is connected to the output of the first immediate output diagnostic circuit, pin I2 is connected to the output of the second immediate output diagnostic circuit, pin I3 is connected to the output of the first delayed output diagnostic circuit, pin I4 is connected to the output of the second delayed output diagnostic circuit, pin I5 is connected to the output of the enable input control diagnostic circuit, pin I6 is connected to the output of the first input control first diagnostic circuit, pin I7 is connected to the output of the first input control second diagnostic circuit, pin I8 is connected to the output of the second input control first diagnostic circuit, and pin I9 is connected to the output of the second input control second diagnostic circuit. Connect MCU A's RX1 pin to MCU B's TX1 pin, and vice versa. MCU A's TX1 pin to MCU B's RX1 pin. MCU A and MCU B's O1 pins are both connected to the input of the first output control driver circuit, and MCU A and MCU B's O2 pins are both connected to the input of the second output control driver circuit. MCU A's RX2 and TX2 pins are connected to the TX1 and RX1 pins of the 485 communication processing chip, respectively. MCU B's RX2 and TX2 pins are connected to the TX2 and RX2 pins of the 485 communication processing chip, respectively, for communication with the 485 communication processing chip.

[0039] In the above-mentioned one-way enable control circuit, two-way input control circuit and two-way output control circuit, the enable input control diagnostic circuit, the first input control first diagnostic circuit, the first input control second diagnostic circuit, the second input control first diagnostic circuit, the second input control second diagnostic circuit, the first immediate output diagnostic circuit, the second immediate output diagnostic circuit, the first delayed output diagnostic circuit and the second delayed output diagnostic circuit are all diagnostic circuits with the same structure. Figure 4 As shown, the diagnostic circuit of the same structure consists of a resistor R, a diode D, and an optocoupler switch U. Resistor R provides voltage reduction protection, while diode D limits the current flow. One end of resistor R is connected to the input terminal J-VCC of the entire diagnostic circuit. The other end of resistor R is connected in series with diode D and then to the primary side of optocoupler switch U. The upper middle terminal of the secondary side of optocoupler switch U is connected to the output terminal MAU-I of the entire diagnostic circuit. The other terminal of the primary side of optocoupler switch U is connected to the input terminal J-GND of the entire diagnostic circuit, and the other terminal of the secondary side of optocoupler switch U is connected to the output terminal MAU-GND of the entire diagnostic circuit. Both the input terminal J-GND and the output terminal MAU-GND are ground terminals. When a high voltage is detected at the input terminal J-VCC of the entire diagnostic circuit, the output terminal MAU-I of optocoupler switch U is turned on, thereby outputting a high-level signal to the MCU chip in the control chip circuit.

[0040] In the above two output control driving circuits, the first output control driving circuit and the second output control driving circuit are both driving control circuits with the same structure. Figure 5 As shown, the drive control circuit is mainly composed of a transistor Q1, the base of the transistor Q1 is connected to one end of the resistor R2, and the other end of the resistor R2 (ie Figure 5The transistor Q1 (connected to one end of MAU-0 in the circuit) serves as the input of the entire drive control circuit and is used to connect to pin O1 or O2 of the MCU chip in a group of control chip circuits. The emitter of the transistor Q1 is connected to GND; the base and emitter of the transistor Q1 are connected via resistor R3; the collector of the transistor Q1 is connected to the power supply VCC via resistor R1 and to ground via two diode branches. One diode branch is connected in series with a diode D1, and the other diode branch is connected in series with a diode D2 and a power supply control relay K. These control the first normally closed switch O1 and the second normally closed switch O2 of the power supply control relay K in the two output control circuits. When the transistor Q1 receives a high-level signal from the MCU chip, it turns on and outputs the high-level VCC to the coil of the power supply control relay K, thereby driving the coil of the power supply control relay K to close. After the coil closes, the first normally closed switch O1 and the second normally closed switch O2 of the power supply control relay K in the two output control circuits are opened, thereby cutting off the power supply to the two output control circuits.

[0041] In addition, the entire high-reliability safety relay is also provided with a lamp indication circuit connected in parallel with the enabling main circuit. The light indication circuit is provided with an LED indicator light for indicating the working status of the entire high-reliability safety relay.

[0042] In the aforementioned high-reliability safety relay for hydrogen liquefaction equipment, the basic circuit uses a relay to create an interlock circuit. The main enable circuit in the enable control circuit activates the main circuit interlock conditions in the two input control circuits, which in turn control the main circuit interlock conditions in the two output control circuits. A control chip circuit uses a diagnostic circuit to monitor the on / off status of the enable control circuit and the main circuits of the two input control circuits. The calculated results are then used to safely disconnect the main circuits of the two output control circuits.

[0043] A high-reliability safety relay suitable for a hydrogen liquefaction device provided in an embodiment of the present invention also includes two instantaneous output circuits and two delayed output circuits. The two instantaneous output circuits use the same circuit structure to be redundant with each other, and the two delayed output circuits also use the same circuit structure to be redundant with each other. Figure 2 and Figure 3 The circuit diagrams of one instant output circuit and one delayed output circuit are shown respectively. Figure 2 In the instant output circuit, the normally open contact switch of the first instant relay J1 and the normally open contact switch of the second instant relay J2 are connected in parallel; Figure 3 In the time-delay output circuit, the normally open contact switch of the first time-delay relay J3 and the normally open contact switch of the second time-delay relay J4 are connected in parallel.

[0044] The working process of the above-mentioned high-reliability safety relay suitable for hydrogen liquefaction equipment is as follows:

[0045] 1. Initialization

[0046] When an external DC24V power supply is connected to VCC24V and GND0V, the entire high-reliability safety relay system starts to be powered. The LED indicator lights up, indicating that the circuit has entered the working state.

[0047] 2. Enable control circuit

[0048] like Figure 1 As shown in the figure, in the enable control circuit, the coil of the enable relay K1 in the main enable circuit and the normally open contact switch form a relay interlock circuit. Enabling relay K1 serves as the master enable control. Enable triggering is performed using the safety relay's built-in button or an external pulse signal connected to enable interfaces XI0+ and XI0-. During the triggering cycle, enable circuit interfaces XI3+ and XI3- must remain connected. For example, an emergency button can be connected to confirm the enable state. Once the enable circuit (the circuit containing enable interfaces XI0+ and XI0-) is connected, the enable signal is triggered, closing the coil of the enable relay K1 and the associated normally open contact switch. This officially activates the two input control circuits and the two output control circuits. Simultaneously, the enable input control diagnostic circuit triggers an optocoupler signal, transmitting a closure signal to pin I5 of the MCU chip in a control chip group. The MCU chip unlocks the safety relay's two output control circuits.

[0049] 3. Input control circuit

[0050] The first interlocking interfaces XI1+ and XI1-, and the second interlocking interfaces XI2+ and XI2-, in the two input control circuits serve as input interfaces. During operation, these input interfaces must remain connected to receive signals from devices requiring interlocking, such as turbine operation protection signals. Once connected, the input control relays in each input control circuit are triggered to energize. To ensure stability, two relays in each input control circuit are simultaneously energized. In the first input control circuit, the coils of input relays K2 and K3 are energized, while in the second input control circuit, the coils of input relays K4 and K5 are energized. Input relays K2, K3, K4, and K5 are all input control relays, and both input control circuits are now activated.

[0051] At the same time, each input control relay has its own input control diagnostic circuit. For example, the input control diagnostic circuits of input relay K2, input relay K3, input relay K4 and input relay K5 are the first input control first diagnostic circuit, the first input control second diagnostic circuit, the second input control first diagnostic circuit, and the second input control second diagnostic circuit, respectively. At this time, the input control diagnostic circuit will detect a closed signal and transmit the signal to a group of MCU chip pins in the control chip circuit, which are I6, I7, I8, and I9. The MCU chip verifies and processes the signal to determine whether the signal meets the trigger conditions and whether the current channel components are working normally.

[0052] 4. Control chip circuit

[0053] The MCU chip in a set of control chip circuits receives the on / off status signals from the enable control circuit and the input control circuit and calculates the results using a built-in algorithm. If all conditions are met, the MCU chip controls the immediate output circuit and the delayed output control circuit of the two output control circuits to close. Otherwise, if any input condition is not met or a fault occurs, the MCU chip triggers the immediate output circuit and the delayed output control circuit of the two output control circuits to disconnect, terminating the device's operating state.

[0054] 5. Output control circuit

[0055] When the interlocking conditions are met, the MCU chip in a group of control chip circuits controls the main loop of the immediate output control circuit to close, thereby controlling the immediate output circuit to close. For example, in a hydrogen liquefaction system, the shutoff signal from the turbine inlet valve will immediately close the valve through the immediate output circuit to protect system safety. At the same time, the MCU chip in another group of control chip circuits controls the main loop of the delayed output control circuit to close. At this time, the delay relay in the main loop controls the delayed output circuit. For example, the bearing air supply valve will be shut off after a set delay, ensuring that the equipment is completely shut down before the air supply is disconnected to avoid damage to the equipment.

[0056] 6. Diagnostic circuit

[0057] The relays in the main loops of the two input control circuits and the output control relays in the main loops of the two output control circuits each have their own diagnostic circuits. These circuits monitor the operating status of the main loops of the two input control circuits and the two output control circuits and transmit the monitoring results to the MCU chip in the control chip group to determine whether the main loops of the two output control circuits are functioning properly. When the MCU chip outputs a high-level signal, it turns on transistor Q1 in the two output control drive circuits, thereby closing the coil of power supply control relay K and disconnecting the power supply to the two output control circuits. Simultaneously, the status detected by all diagnostic circuits is analyzed by the MCU chip in the control chip group and output in real time to the 485 transmission chip, which transmits the device's real-time status to other control systems for real-time monitoring.

[0058] The high-reliability safety relay for hydrogen liquefaction equipment provided in the embodiments of the present invention can always be in the best operating state with high reliability, and can also realize functions such as emergency output cut-off, input channel detection, fault safety protection, and delayed output. Specifically:

[0059] Improved safety: Through a dual monitoring mechanism, including physical interlocking and electronic monitoring, the system can respond quickly when an abnormality is found in any monitoring channel. The fault alarm output is provided to the third-party device interface to provide timely feedback on the equipment operating status, thereby improving the safety of the entire control system.

[0060] Enhanced reliability: The back-to-back design of the control core forms a redundant control system to cope with single point failures and ensure the continuity and reliability of the control system.

[0061] With multiple output modes: with immediate output and delayed output channels, through the adjustable delay output circuit, the delay length can be adjusted according to different control requirements, so that the relay can better adapt to various control modes.

[0062] High integration and good thermal management are achieved: by integrating components onto a single PCB, a small size and flexible installation are achieved while ensuring long-term stable operation and further improving reliability.

[0063] It should be noted that the above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the various embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A high reliability safety relay suitable for a hydrogen liquefaction device, characterized in that: The relay includes: an enable control circuit, at least one input control circuit, at least one output control circuit and a control chip circuit; the enable control circuit includes an enable main circuit, which is provided with an enable interface; the input control circuit includes an input control main circuit, which is provided with an input interface for connecting to an interlocking device signal; the output control circuit includes an output control main circuit; the enable main circuit, the input control main circuit and the control chip circuit are all controlled to connect to the output control main circuit; A coil of an enabling relay is provided in the enabling main circuit; An input relay coil is provided in the input control main circuit; The output control main circuit is provided with a normally open contact switch of an enabling relay and a normally open contact switch of an input relay; The output control main circuit is also provided with a normally closed switch controlled by the control chip circuit; The enable control circuit, input control circuit and output control circuit are also each provided with a diagnostic circuit for detecting the working status of the enable main circuit, the input control main circuit and the output control main circuit; the output end of the diagnostic circuit is connected to the control chip circuit; the relay includes at least two redundant input control circuits, and the input control main circuit of each input control circuit is provided with an input interface and a group of input relay coils in series, and a group of relay coils is composed of the coils of at least two input relays connected in parallel; a normally open contact switch of the input relay is provided in the enable main circuit; the relay includes at least two redundant output control circuits, and the at least two output control circuits include at least one immediate output control circuit and at least one delayed output control circuit.

2. A high-reliability safety relay suitable for a hydrogen liquefaction device according to claim 1, characterized in that: The normally open contact switches of each group of input relays, the enabling interface and the coil of the enabling relay are sequentially arranged in series in the enabling main circuit; the normally open contact switches of each group of input relays are composed of a normally open contact switch of each input relay corresponding to a group of input relay coils in the input control main circuit of an input control circuit arranged in parallel; the enabling interface is also provided with a push button switch and a self-locking branch of the enabling relay in parallel, and the normally open contact switch of the enabling relay and the enabling circuit interface are arranged in series in the self-locking branch.

3. A high-reliability safety relay suitable for a hydrogen liquefaction device according to claim 1, characterized in that: In the output control main loop of each instant output control circuit, a normally closed switch controlled by the control chip circuit, a normally open contact switch of the enable relay, a group of input relay normally open contact switches and a group of instant relay coils are arranged in series in sequence. A group of input relay normally open contact switches is composed of a normally open contact switch of each input relay corresponding to a group of input relay coils in the input control main loop of one input control circuit being arranged in parallel. A group of instant relay coils is composed of the coils of at least two instant relays connected in parallel.

4. A high-reliability safety relay suitable for a hydrogen liquefaction device according to claim 1, characterized in that: In the output control main circuit of each delayed output control circuit, a normally closed switch controlled by the control chip circuit, a normally open contact switch of the enable relay, a group of input relay normally open contact switches and a group of delay relay coils are arranged in series in sequence. A group of input relay normally open contact switches is composed of a normally open contact switch of each input relay corresponding to a group of input relay coils in the input control main circuit of one input control circuit arranged in parallel. A group of delay relay coils is composed of the coils of at least two delay relays connected in parallel.

5. A high-reliability safety relay suitable for a hydrogen liquefaction device according to claim 1, characterized in that: The control chip circuit includes at least two redundant MCU chips and at least two output control drive circuits. Each MCU chip samples and connects to each diagnostic circuit, and each MCU chip controls and connects to each output control drive circuit. Each output control drive circuit is provided with a power supply control relay coil for controlling the normally closed switch in the output control main circuit of one output control circuit.

6. A high-reliability safety relay suitable for a hydrogen liquefaction device according to claim 5, characterized in that: Each output control drive circuit includes a transistor; the base of the transistor is connected to the input end of the output control drive circuit through a resistor, the collector of the transistor is connected to the power supply through a resistor, and the collector is also grounded through two diode branches, one diode branch is provided with a diode in series, and the other diode branch is provided with a diode and a power supply control relay coil in series.

7. A high-reliability safety relay suitable for a hydrogen liquefaction device according to claim 1, characterized in that: The diagnostic circuit consists of a resistor, a diode and an optocoupler switch. The primary side of the optocoupler switch is connected to the input end of the diagnostic circuit through a series resistor and a diode, and the secondary side of the optocoupler switch is connected to the output end of the diagnostic circuit.

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