A direct current power relay capable of fast alarming

Abstract

The application discloses a direct-current power relay capable of quickly alarming, and belongs to the technical field of power system alarming. The direct-current power relay comprises a quick-insert electromagnetic driving module and a composite function base. When overvoltage, overcurrent, overheating, gas-liquid invasion or abnormal pressure occurs, the direct-current power relay utilizes a "slip-pressure-touch" mechanism, a bimetal linkage, expansion triggering and phase change-corrugated pipe coupling to output dry contacts within 20 ms to 2 s, and drives EMS / PLC / sound-light alarming. Low-friction sliding pairs, elastic automatic reset and replaceable low-melting-point alloy gaskets ensure repeated / fused double-mode protection, and the direct-current power relay is compatible with direct-current systems such as energy storage and charging piles, and the reliability of the direct-current power relay is improved without changing the volume.

Description

Technical Field

[0001] This invention relates to the field of power system alarm technology, and in particular to a DC power relay capable of rapid alarm. Background Technology

[0002] In applications such as new energy power generation, energy storage, and DC fast charging, the DC bus voltage level is constantly increasing (800V, 1000V, and even 1500V), and the power density is continuously increasing, which puts forward higher requirements for the safety and reliability of DC power relays.

[0003] Traditional electromagnetic relays or solid-state relays typically only have a single main contact switching function. Their protection action relies on external fuses, Hall sensors, or software algorithms, and they have the following common problems: existing relays lack the ability to self-sensing and self-alarm for multiple faults such as overvoltage, overcurrent, overheating, gas and liquid intrusion, and internal pressure rise. They must rely on distributed sensor networks, which makes the system complex, costly, and has many fault points. After overload action, manual on-site reset or fuse replacement is required, and the downtime is long in unattended scenarios such as charging piles and energy storage containers.

[0004] To shorten response time, some manufacturers employ magnetic blowout + permanent magnet arc extinguishing, double-break, or bridge contact structures. However, these approaches are still limited to improving the breaking capacity of the main contacts and do not address the issues of fault detection and alarm speed. Another solution involves connecting an electronic fast-acting fuse (Pyro-Fuse) in parallel with the relay, utilizing the explosive charge to drive a piston to cut off the busbar. This can operate within 1ms to 3ms, but it is costly, requires single use, and is not resettable. Therefore, a DC power relay capable of rapid alarm is proposed. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a DC power relay capable of rapid alarm.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A DC power relay capable of rapid alarm includes a quick-connect electromagnetic drive module and a composite function base. One end of the quick-connect electromagnetic drive module is laterally inserted into the composite function base. The composite function base includes a main terminal block and a gas / liquid intrusion alarm module disposed at the end away from the quick-connect electromagnetic drive module. An overheat alarm module is inserted into one side of the gas / liquid intrusion alarm module, and an overvoltage / overcurrent alarm module is inserted into the bottom position of the overheat alarm module.

[0008] Preferably, the main terminal block includes a terminal body and insert slots arranged on one side end face of the terminal body, and locking holes are arranged on the side end face of the terminal body.

[0009] Preferably, the gas-liquid intrusion alarm module includes two sets of oppositely opened vent slits, an expansion cavity is opened at the interval between the two sets of opposite vent slits, and a micro-motion trigger piece is opened at the bottom position of the inner end face of the vent slit.

[0010] Two sets of opposing slit-type ventilation slits are located on the side wall of the gas and liquid intrusion alarm module. The slit width is 0.05-0.1mm. They can prevent large particles such as sand and dust, but allow gas or liquid to penetrate into the inner cavity, achieving the detection premise of "allowing entry but not blocking".

[0011] The expansion chamber is located between two sets of breathable slits and is filled with highly absorbent / gas-absorbing polymer expansion strips. When exposed to water, oil, or specific gases such as SF6 or hydrogen, the expansion strips increase in volume by 3-5 times within 1-3 seconds, generating a thrust of 1-2N.

[0012] The micro-motion trigger piece with a slot at the bottom of the ventilation slit acts as an elastic cantilever, with one end fixed to the inside of the ventilation slit and the other end extending into the expansion cavity; after the expansion bar increases in volume, it pushes the micro-motion trigger piece to bend downward by 0.2mm, so that its end closes with the alarm contact below, and outputs a dry contact signal;

[0013] The closed loop can directly drive the fast-closing contact or be connected in parallel to remote monitoring to achieve "instant alarm for gas-liquid intrusion"; the expansion strip changes color from blue to red after absorbing moisture / gas, providing visual secondary confirmation and facilitating maintenance personnel to quickly locate the leak source;

[0014] Through a cascaded action of "sensing from the vent slit to the expansion cavity, causing the micro-motion trigger plate to close", in gas or liquid.

[0015] Preferably, the overheat alarm module includes a thermal frame and bimetallic cavities respectively opened at the middle of the two end faces of the thermal frame. Thermal trigger sliders are installed on both sides of the inner cavity of the thermal frame, and overheat alarm contacts are inserted at the interval between the two sets of thermal trigger sliders.

[0016] The thermal frame is directly attached to the coil or busbar, and the high thermal conductivity metal quickly absorbs the Joule heat generated by the overvoltage and high current, so that the overall temperature rise can be sensed within 1 to 2 seconds.

[0017] The bimetallic plate cavity is located on both ends of the thermistor frame, and the bimetallic plate is sandwiched inside. As the temperature rises, the bimetallic plate arches outward, providing mechanical thrust and converting the temperature signal into a controllable displacement.

[0018] The thermal trigger sliders are installed on both sides of the inner cavity of the thermal skeleton. After being pushed by the bimetallic strip, they move inward synchronously along the guide groove of the bimetallic strip cavity, forming a "top-to-top" action to ensure that the direction of the thrust is completely coaxial with the overheat alarm contact and to avoid lateral jamming.

[0019] The overheat alarm contact is inserted between two sets of thermal trigger sliders. When the sliders move inward, the overheat alarm contact is pressed down and closes with the lower stationary contact to form an independent overheat alarm circuit. This circuit can be connected in parallel with the overvoltage alarm circuit of the overvoltage / overcurrent alarm module to achieve dual redundancy alarm of temperature and pressure. It can also drive the temperature indicator or fan independently to facilitate quick on-site fault location.

[0020] Through the cascaded action of "rapid heat conduction of the thermal skeleton causing deformation of the bimetallic spring, thereby triggering the thermal trigger slider to push the overheat alarm contact to close", a dry contact signal is output within 2 seconds when the coil or busbar is abnormally heated due to overvoltage and high current, so as to realize overheat alarm and avoid secondary faults such as insulation aging and coil burnout.

[0021] Preferably, the overvoltage / overcurrent alarm module includes a main contact and a buzzer cavity disposed on the side end face of the main contact. A sliding guide rail is arranged laterally on one side of the buzzer cavity. Sliding slider arms are slidably disposed on both sides of the side end face of the sliding guide rail. Multiple sets of sliding slider arms are connected in an array, with a sliding slider arm installed at one end. Two sets of sliding slider arms arranged opposite each other are connected in series by an elastic linkage. The gap between the two sets of elastic linkages is connected in series by a quick-closing contact.

[0022] When the relay detects an overvoltage or overcurrent, the overload current flows through one end of the slider contact arm and moves in opposite directions along the sliding rail. During this movement, the two sets of opposing slider contact arms press inward against the elastic linkage, causing the quick-closing contact to move downward and contact the top of the sliding rail, thus forming a closed circuit and triggering an alarm signal.

[0023] The sliding rail provides stable sliding support for the slider contact arm, ensuring that it can move along a predetermined trajectory when subjected to force, maintaining the accuracy of the alarm action; when an overload current passes through, the slider contact arm slides along the sliding rail due to electromagnetic or mechanical force, receives the overload signal at one end, converts this signal into mechanical motion, and transmits it to subsequent components; multiple sets of slider contact arms are interconnected and connected in series with elastic linkage components to form a mechanical and electrical linkage structure, jointly participating in the transmission of alarm signals.

[0024] After an overvoltage / overcurrent signal is triggered, the overvoltage / overcurrent alarm module completes the circuit closure within tens of milliseconds through a three-step action of "sliding, pressing, and touching," significantly shortening the response time of traditional relays.

[0025] The sliding guide rail and the slider arm sliding pair adopt a low-friction design to prevent jamming. The elastic linkage is made of elastic material. In the initial state, it is naturally extended. When the slider arm is pressed inward, the elastic linkage undergoes elastic deformation and provides a rebound force. It can automatically reset after the action to ensure that repeated triggering does not fail.

[0026] The quick-closing contact and the sliding rail have surface-to-surface contact, resulting in low contact resistance and resistance to welding. The buzzer alarm mechanism is built into the buzzer cavity and shares the same composite functional base with the relay main circuit. The quick-closing contact can be connected in parallel to remote monitoring, PLC or audible and visual alarms, making it suitable for various scenarios such as DC power distribution, new energy storage, and charging piles.

[0027] The main contacts of the relay are connected in series between the bus and the energy storage converter, and the fast-closing contact terminals are connected in parallel to the DI port of the EMS energy management system and the on-site audible and visual alarm.

[0028] Overload current enters the sliding rail through the slider contact arm and slides in the opposite direction. At this time, the elastic linkage is compressed to close the fast closing contact with the sliding rail. The EMS receives the dry contact signal within 20ms, automatically unloads the photovoltaic inverter and disconnects the energy storage charging circuit. The on-site buzzer sounds an alarm simultaneously, and maintenance personnel arrive on-site within 30s to confirm. The duration of bus overvoltage is shortened from the traditional 300ms to <50ms, avoiding IGBT module overvoltage breakdown.

[0029] The main contacts of the relay are connected in series at the output end of the charging pile, and the fast-closing contact terminal is connected to the CAN bus alarm node of the charging pile main control board.

[0030] When the vehicle's BMS experiences an abnormal load of 300A (rated at 250A), the rapid closing contacts close within 30ms, and the main control board immediately reduces the power to 150A. At the same time, it alerts the owner via a CAN message. After the fault is cleared, the elastic linkage automatically resets, and the relay resumes full power output, preventing the fuse from blowing, reducing downtime by 90%, and improving the availability of the charging station.

[0031] Preferably, the quick-connect electromagnetic drive module includes an insulating shell and a moving iron core guide rod that penetrates into the inner cavity of the insulating shell. Lateral latches are installed on both sides of the edge of the insulating shell, and a pressure-overheat alarm is vertically inserted into the groove of the lateral latch.

[0032] Preferably, the locking hole is inserted through the inner cavity of the moving iron core guide rod, so that the quick-connect electromagnetic drive module and the composite functional base are combined into a whole.

[0033] Preferably, the pressure-overheat alarm includes a bellows and a heat-conducting sleeve installed on the outer ring of the bellows. A phase change thermistor is fitted around the outer ring of the heat-conducting sleeve. Bimetallic discs are installed on both sides of the outer ring of the phase change thermistor. A linkage rod is fitted around the other end of the bimetallic disc. The inner cavity of the bellows is connected to the main cavity of the relay to sense changes in internal air pressure in real time. The heat-conducting sleeve synchronously converts the deformation displacement of the bellows into changes in the heat conduction area. The phase change thermistor is filled with a low-boiling-point phase change liquid with a boiling point of ≈85°C. When the internal pressure increases and causes the bellows to expand, the contact area between the heat-conducting sleeve and the phase change thermistor increases, the phase change liquid rapidly vaporizes and absorbs heat, and the cavity temperature rises sharply.

[0034] The bimetallic disc is fixed at the top of the phase change thermistor cavity; when the temperature rises suddenly, the bimetallic disc jumps, and the upper end of the linkage rod is pushed by the bimetallic disc, while the lower end passes through the phase change thermistor cavity and enters the center hole of the pressure-overheat alarm.

[0035] Preferably, the linkage rod includes a conductive disk and elastic contact fingers installed on both sides of the conductive disk, with a low melting point alloy gasket sandwiched between the two sets of elastic contact fingers.

[0036] When the linkage rod is pushed downward by the bimetallic disc, the conductive disk and the elastic contact finger close, forming a dry contact alarm; if the temperature continues to rise to the melting point of the low melting point alloy gasket, the low melting point alloy gasket melts, the conductive disk is permanently pressed down, and the elastic contact finger locks and closes, realizing a "fusible-locking" alarm.

[0037] Two sets of elastic contact fingers are connected in series through the series output terminal, which can directly drive the in-machine buzzer, remote PLC or SCADA system to realize the closed loop of "excessive pressure leads to excessive heat, so that an alarm can be triggered in time";

[0038] The pressure-overheat alarm utilizes a three-stage coupling of "bellows-phase change thermistor-bimetallic disc" to complete "sensing-triggering-alarm" within 2-3 seconds when the internal pressure rises abnormally and heat accumulates. It also takes into account both recoverable and irreversible protection requirements through two modes: "repeatable tripping" or "one-time fuse". This significantly improves the safety of the relay in closed, high-voltage DC systems.

[0039] Level 1 resettable alarm: The bimetallic disc suddenly jumps, causing the linkage rod to move downward, which drives the conductive plate and the elastic contact finger to close. At this time, the dry contact immediately outputs, driving the local buzzer / remote PLC; when the pressure drops, the bimetallic disc automatically rebounds, the circuit is broken, and the system can be used again.

[0040] Level 2 fuse lockout alarm: If the pressure continues to rise and the temperature exceeds the set threshold, the low melting point alloy gasket melts, causing the conductive disk to lose support and be permanently pressed down, resulting in the elastic contact finger being mechanically locked and remaining permanently closed; at this time, regardless of whether the pressure recovers, the alarm signal continues to be output until the low melting point alloy gasket is manually replaced, to prevent the danger from being missed due to repeated faults.

[0041] Preferably, the two sets of elastic contact fingers are connected in series through a series output terminal. The two sets of elastic contact fingers are connected in series through the series output terminal to form a redundant circuit. If the connector in any series output terminal fails, the other set can still conduct. The output terminal can be directly connected to SCADA to realize a complete closed loop of "excessive pressure leading to excessive heat, thereby triggering an immediate and continuous alarm".

[0042] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0043] 1. Extremely short response time: The overvoltage / overcurrent alarm module adopts a three-step cascade of "slide-pressure-touch", which completes the circuit closure within tens of milliseconds. The duration of bus overvoltage is shortened from the traditional 300ms to <50ms, which significantly reduces the risk of overvoltage breakdown of power devices such as IGBTs.

[0044] 2. Mechanical-electric integrated linkage: The slider arm, elastic linkage component, and quick-closing contact form a surface-to-surface contact structure with low friction and low lateral force, resulting in low action resistance, reliable rebound, and no failure after repeated triggering, reducing maintenance cycle by more than 90%.

[0045] 3. Plug and play for multiple scenarios: The fast-closing contacts can be directly connected in parallel to external systems such as EMS, PLC, CAN, SCADA, and audible and visual alarms without the need for additional drive circuits. It is suitable for diverse working conditions such as DC power distribution, new energy storage, charging piles, and high-voltage sealed systems.

[0046] 4. Temperature and pressure dual redundancy protection: The overheat alarm circuit composed of the thermal frame 231, bimetallic strip and thermal trigger slider is connected in parallel with the overvoltage / overcurrent alarm circuit. Dry contact is output within 2 seconds to avoid secondary faults such as insulation aging and coil burnout caused by single detection failure.

[0047] 5. Real-time gas-liquid intrusion alarm: "Intrusion is allowed but not blocked" detection is achieved between the vent slit, expansion chamber and micro-motion trigger plate. Leak detection is completed within 1-3 seconds and dry contact is output. The color change of the expansion strip provides visual secondary confirmation, improving the reliability of outdoor and chemical environments.

[0048] 6. Pressure-overheat coupling self-protection: The three-level coupling between the bellows, the phase change thermistor cavity and the bimetallic disc can complete the "sensing-triggering-alarm" process within 2-3 seconds. It also has two levels of protection: resettable snap-on and one-time fuse lock-off, taking into account both recoverable operation and irreversible safe shutdown requirements. Attached Figure Description

[0049] Figure 1 This is a three-dimensional structural diagram of a DC power relay capable of rapid alarm proposed in this invention;

[0050] Figure 2 This is a schematic diagram of a composite functional base structure for a DC power relay capable of rapid alarm proposed in this invention.

[0051] Figure 3 This is a schematic diagram of the main terminal block structure of a DC power relay capable of rapid alarm proposed in this invention;

[0052] Figure 4 This is a schematic diagram of the gas and liquid intrusion alarm module of a DC power relay capable of rapid alarm proposed in this invention;

[0053] Figure 5 This is a schematic diagram of the overheat alarm module structure of a DC power relay capable of rapid alarm proposed in this invention.

[0054] Figure 6 This is a schematic diagram of the overvoltage / overcurrent alarm module structure of a DC power relay capable of rapid alarm proposed in this invention;

[0055] Figure 7 This is a schematic diagram of the internal structure of an overvoltage / overcurrent alarm module for a DC power relay capable of rapid alarm, as proposed in this invention.

[0056] Figure 8 This is a schematic diagram of the quick-connect electromagnetic drive module structure of a DC power relay capable of rapid alarm proposed in this invention.

[0057] Figure 9 This is a schematic diagram of the moving iron core guide rod structure of a DC power relay capable of rapid alarm proposed in this invention;

[0058] Figure 10 This is a schematic diagram of the pressure-overheat alarm structure of a DC power relay capable of rapid alarm proposed in this invention.

[0059] Figure 11 This is a schematic diagram of the linkage rod structure of a DC power relay capable of rapid alarm proposed in this invention.

[0060] In the diagram: 1. Quick-connect electromagnetic drive module; 11. Insulating housing; 12. Moving iron core guide rod; 13. Side latch; 14. Pressure-overheat alarm; 141. Bellows; 142. Heat-conducting sleeve; 143. Phase change thermistor cavity; 144. Bimetallic disc; 145. Linkage rod; 1451. Conductive disk; 1452. Elastic contact finger; 1453. Low melting point alloy gasket; 146. Series output terminal; 2. Composite function base; 21. Main terminal block; 211. Terminal body; 212 213. Insert slot; 22. Locking hole; 23. Gas / liquid intrusion alarm module; 221. Ventilation slit; 222. Expansion chamber; 223. Micro-motion trigger plate; 23. Overheat alarm module; 231. Thermistor frame; 232. Bimetallic strip cavity; 233. Thermal trigger slider; 234. Overheat alarm contact; 245. Overvoltage / overcurrent alarm module; 241. Main contact; 242. Buzzer cavity; 243. Sliding guide rail; 244. Slider contact arm; 245. Elastic linkage; 246. Quick-closing contact. Detailed Implementation

[0061] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0062] Reference Figures 1-10 Example 1: A DC power relay capable of rapid alarm includes a quick-connect electromagnetic drive module 1 and a composite function base 2. One end of the quick-connect electromagnetic drive module 1 is laterally inserted into the composite function base 2. The composite function base 2 includes a main terminal block 21 and a gas / liquid intrusion alarm module 22 disposed at the end away from the quick-connect electromagnetic drive module 1. An overheat alarm module 23 is inserted into one side of the gas / liquid intrusion alarm module 22, and an overvoltage / overcurrent alarm module 24 is inserted into the bottom position of the overheat alarm module 23.

[0063] The main terminal block 21 includes a terminal body 211 and insert slots 212 arranged on one side end face of the terminal body 211. Locking holes 213 are arranged on the side end face of the terminal body 211.

[0064] The gas and liquid intrusion alarm module 22 includes two sets of oppositely opened ventilation slits 221, an expansion cavity 222 is opened at the interval between the two sets of opposite ventilation slits 221, and a micro-motion trigger piece 223 is opened at the bottom position of the inner end face of the ventilation slit 221.

[0065] Two sets of opposing slit-type ventilation slits 221 are located on the side wall of the gas and liquid intrusion alarm module 22. The slit width is 0.05-0.1mm, which can prevent large particles such as sand and dust, but allow gas or liquid to penetrate into the inner cavity, thus achieving the detection premise of "allowing entry but not blocking".

[0066] The expansion chamber 222 is located between two sets of breathable slits 221 and is filled with a highly absorbent / gas-absorbing polymer expansion strip. When exposed to water, oil or specific gases such as SF6 or hydrogen, the expansion strip increases in volume by 3-5 times within 1-3 seconds, generating a thrust of 1-2N.

[0067] The micro-motion trigger plate 223 with a groove at the bottom of the ventilation slit 221 acts as an elastic cantilever, with one end fixed to the inside of the ventilation slit 221 and the other end extending into the expansion cavity 222; after the expansion bar increases in volume, it pushes the micro-motion trigger plate 223 to bend downward by 0.2mm, so that its end closes with the alarm contact below and outputs a dry contact signal.

[0068] The closed circuit can directly drive the fast-closing contact 246, or it can be connected in parallel to remote monitoring to achieve "instant alarm for gas-liquid intrusion". The expansion strip changes color from blue to red after absorbing moisture / air, providing visual secondary confirmation, which makes it easy for maintenance personnel to quickly locate the leak source. Through the cascade action of "sensing from the vent slit 221 to the expansion chamber 222, causing the micro-motion trigger 223 to close", an alarm is issued within seconds when gas or liquid accidentally enters the relay cavity, preventing insulation degradation, corrosion or short circuit faults, and improving the reliability of the device in humid, outdoor and chemical environments.

[0069] Example 2: The overheat alarm module 23 includes a thermal frame 231 and bimetallic cavities 232 respectively opened at the middle of the two end faces of the thermal frame 231. Thermal trigger sliders 233 are installed on both sides of the inner cavity of the thermal frame 231, and overheat alarm contacts 234 are inserted at the interval between the two sets of thermal trigger sliders 233.

[0070] The thermal frame 231 is directly attached to the coil or busbar. It utilizes the high thermal conductivity metal to quickly absorb the Joule heat generated by overvoltage and high current, so that the overall temperature rise can be sensed within 1 to 2 seconds.

[0071] The bimetallic plate cavity 232 is formed on both ends of the thermistor frame 231, and the bimetallic plate is sandwiched inside; as the temperature rises, the bimetallic plate arches outward, providing mechanical thrust and converting the temperature signal into a controllable displacement.

[0072] The thermal trigger slider 233 is installed on both sides of the inner cavity of the thermal skeleton 231. After being pushed by the bimetallic strip, it moves inward synchronously along the guide groove of the bimetallic strip cavity 232 to form a "top-to-top" action, ensuring that the direction of the thrust is completely coaxial with the overheat alarm contact 234, and avoiding lateral jamming.

[0073] The overheat alarm contact 234 is inserted between two sets of thermal trigger sliders 233. When the sliders move inward, the overheat alarm contact 234 is pressed down and closes with the lower stationary contact, forming an independent overheat alarm circuit. This circuit can be connected in parallel with the overvoltage alarm circuit of the overvoltage / overcurrent alarm module 24 to achieve dual redundancy alarm of temperature and pressure. It can also drive the temperature indicator light or fan independently, which is convenient for quick on-site fault location.

[0074] In Example 3, through the cascaded action of "rapid heat conduction of the thermal frame 231 causing deformation of the bimetallic spring, thereby triggering the thermal trigger slider 233 to push the overheat alarm contact 234 to close", a dry contact signal is output within 2 seconds when the coil or busbar is abnormally heated due to overvoltage and high current, so as to realize overheat alarm and avoid secondary faults such as insulation aging and coil burnout.

[0075] Example 4: The overvoltage / overcurrent alarm module 24 includes a main contact 241 and a buzzer cavity 242 disposed on the side end face of the main contact 241. A sliding guide rail 243 is horizontally disposed on one side of the buzzer cavity 242. Sliding slider arms 244 are slidably disposed on both sides of the side end face of the sliding guide rail 243. Multiple sets of sliding slider arms 244 are connected in an array, with one end of each set of sliding slider arms 244 installed. Two sets of sliding slider arms 244 disposed opposite to each other are connected in series by elastic linkage 245. The gaps between the two sets of elastic linkage 245 are connected in series by quick-closing contacts 246.

[0076] When the relay detects an overvoltage or overcurrent, the overload current passes through one end of the slider contact arm 244 and moves in the opposite direction along the sliding guide rail 243. During the movement, the two sets of opposing slider contact arms 244 press the elastic linkage 245 inward, thereby causing the quick-closing contact 246 to move downward and contact the top of the sliding guide rail 243, thus forming a closed circuit and triggering an alarm signal.

[0077] The sliding rail 243 provides stable sliding support for the slider contact arm 244, ensuring that it can move along a predetermined trajectory when subjected to force, thus maintaining the accuracy of the alarm action. When an overload current passes through, the slider contact arm 244 slides along the sliding rail 243 due to electromagnetic or mechanical force, receives the overload signal at one end, converts the signal into mechanical motion, and transmits it to subsequent components. Multiple sets of slider contact arms 244 are interconnected and connected in series with the elastic linkage 245 to form a mechanical and electrical linkage structure, which jointly participates in the transmission of the alarm signal.

[0078] In Example 5, after the overvoltage / overcurrent signal is triggered, the overvoltage / overcurrent alarm module 24 completes the circuit closure within tens of milliseconds through a three-step action of "sliding, pressing, and touching", which significantly shortens the response time of traditional relays.

[0079] The sliding guide rail 243 and the slider arm 244 sliding pair adopt a low friction design to prevent jamming. The elastic linkage 245 is made of elastic material. In the initial state, it is naturally extended. When the slider arm 244 is pressed inward, the elastic linkage 245 undergoes elastic deformation and provides a rebound force. After the action, it can automatically reset to ensure that repeated triggering does not fail.

[0080] The core of this embodiment is that the quick-closing contact 246 and the sliding guide rail 243 have surface-to-surface contact, resulting in low contact resistance and resistance to welding; the buzzer alarm mechanism is built into the inner cavity of the buzzer cavity 242 and shares the same composite functional base 2 with the relay main circuit; the quick-closing contact 246 can be connected in parallel to remote monitoring, PLC or audible and visual alarms, and is suitable for various scenarios such as DC power distribution, new energy storage, and charging piles.

[0081] To distinguish it from the above embodiment 5, a different embodiment is proposed: the main contact 241 of the relay is connected in series between the bus and the energy storage converter, and the terminal of the fast closing contact 246 is connected in parallel to the DI port of the EMS energy management system and the on-site audible and visual alarm.

[0082] Overload current enters the sliding rail 243 through the slider contact arm 244 and slides in the opposite direction. At this time, the elastic linkage 245 is compressed to close the fast closing contact 246 with the sliding rail 243. The EMS receives the dry contact signal within 20ms, automatically unloads the photovoltaic inverter and disconnects the energy storage charging circuit. The on-site buzzer alarms simultaneously, and maintenance personnel arrive on-site within 30s to confirm. The duration of bus overvoltage is shortened from the traditional 300ms to <50ms, avoiding IGBT module overvoltage breakdown.

[0083] The relay main contact 241 is connected in series at the output end of the charging pile. The fast-closing contact 246 is connected to the CAN bus alarm node of the charging pile main control board. If the vehicle BMS is abnormally overloaded (300A, rated 250A), the fast-closing contact 246 closes within 30ms, and the main control board immediately reduces the power to 150A. At the same time, it alerts the owner via CAN message. After the fault is cleared, the elastic linkage 245 automatically resets, and the relay resumes full power output, preventing the fuse from blowing, reducing downtime by 90%, and improving the availability of the charging pile.

[0084] Example 6: The quick-connect electromagnetic drive module 1 includes an insulating shell 11 and a moving iron core guide rod 12 that penetrates into the inner cavity of the insulating shell 11. Lateral latches 13 are installed on both sides of the edge of the insulating shell 11. A pressure-overheat alarm 14 is vertically inserted into the groove of the lateral latch 13. The locking hole 213 is inserted through the inner cavity of the moving iron core guide rod 12, so that the quick-connect electromagnetic drive module 1 and the composite functional base 2 are combined into a whole.

[0085] The pressure-overheat alarm 14 includes a bellows 141 and a heat-conducting sleeve 142 installed on the outer ring of the bellows 141. A phase change thermistor 143 is sleeved on the outer ring of the heat-conducting sleeve 142. Bimetallic discs 144 are installed on both sides of the outer ring of the phase change thermistor 143. A linkage rod 145 is sleeved on the other end of the bimetallic discs 144. The inner cavity of the bellows 141 is connected to the main cavity of the relay to sense changes in internal air pressure in real time. The heat-conducting sleeve 142 synchronously converts the deformation displacement of the bellows 141 into a change in heat conduction area. The phase change thermistor 143 is filled with a low-boiling-point phase change liquid with a boiling point of ≈85°C. When the internal pressure increases and causes the bellows 141 to expand, the contact area between the heat-conducting sleeve 142 and the phase change thermistor 143 increases, the phase change liquid rapidly vaporizes and absorbs heat, and the cavity temperature rises sharply.

[0086] The bimetallic disc 144 is fixed to the top of the phase change thermistor 143; when the temperature rises suddenly, the bimetallic disc 144 jumps, the upper end of the linkage rod 145 is pushed by the bimetallic disc 144, and the lower end passes through the phase change thermistor 143 and enters the center hole of the pressure-overheat alarm 14.

[0087] Example 7: The linkage rod 145 includes a conductive disk 1451 and elastic contact fingers 1452 installed on both sides of the conductive disk 1451. A low melting point alloy gasket 1453 is sandwiched between the two sets of elastic contact fingers 1452.

[0088] When the linkage rod 145 is pushed downward by the bimetallic disc 144, the conductive disk 1451 and the elastic contact finger 1452 close, forming a dry contact alarm; if the temperature continues to rise to the melting point of the low melting point alloy pad 1453, the low melting point alloy pad 1453 melts, the conductive disk 1451 is permanently pressed down, and the elastic contact finger 1452 locks and closes, realizing a "fuse-lock" alarm.

[0089] Two sets of elastic contact fingers 1452 are connected in series through the series output terminal 146, which can directly drive the in-machine buzzer, remote PLC or SCADA system to realize a closed loop of "excessive pressure leading to excessive heat, thus enabling immediate alarm".

[0090] The pressure-overheat alarm 14 utilizes a three-stage coupling of "bellows 141 - phase change thermistor 143 - bimetallic disc 144" to complete "sensing-triggering-alarm" within 2-3 seconds when the internal pressure rises abnormally and heat accumulates. It also takes into account both recoverable and irreversible protection requirements through two modes: "repeatable tripping" or "one-time fuse blowing", which significantly improves the safety of the relay in closed, high-voltage DC systems.

[0091] To distinguish it from Embodiment 7 described above, the following parallel distinguishing embodiments are proposed:

[0092] Level 1 resettable alarm: The bimetallic disc 144 suddenly jumps, causing the linkage rod 145 to move downward, driving the conductive plate 1451 and the elastic contact finger 1452 to close. At this time, the dry contact immediately outputs, driving the local buzzer / remote PLC; when the pressure drops, the bimetallic disc 144 automatically rebounds, the circuit is broken, and the system can be used again.

[0093] Level 2 fuse lockout alarm: If the pressure continues to rise and the temperature exceeds the set threshold, the low melting point alloy gasket 1453 melts, causing the conductive disk 1451 to lose support and be permanently pressed down, resulting in the elastic contact finger 1452 being mechanically locked and kept permanently closed; at this time, regardless of whether the pressure recovers, the alarm signal continues to be output until the low melting point alloy gasket 1453 is manually replaced, to prevent the danger from being missed due to repeated faults.

[0094] In Example 8, the two sets of elastic contact fingers 1452 are connected in series through a series output terminal 146. The two sets of elastic contact fingers 1452 are connected in series through the series output terminal 146 to form a redundant circuit. If the connector in any series output terminal 146 fails, the other set can still conduct. The output terminal can be directly connected to SCADA to realize a complete closed loop of "excessive pressure leading to excessive heat, thereby triggering an immediate and continuous alarm".

[0095] In summary: When overvoltage / overcurrent occurs at the DC bus or charging pile output terminal, the slider contact arm 244 slides in the opposite direction on the sliding guide rail 243 and presses against the elastic linkage 245, causing the fast-closing contact 246 to close within 20-30ms. The dry contact signal is directly sent to the EMS or charging pile main control board to achieve load derating, main circuit disconnection, and on-site / remote alarm; the duration of bus overvoltage is reduced from 300ms to <50ms, and the number of charging pile shutdowns is reduced by 90%.

[0096] Overvoltage current causes the coil or busbar to heat up. The thermal frame 231 conducts the heat signal to the bimetallic cavity 232 within 1-2 seconds. The bimetallic plate arches up and pushes the thermal trigger slider 233, causing the overheat alarm contact 234 to close. It independently outputs a "temperature-pressure" dual redundant alarm, or directly drives the fan / indicator light to prevent the coil from burning out.

[0097] External moisture, oil, or SF6 gases enter the expansion chamber 222 through the vent slit 221. The volume of the polymer expansion strip increases instantly, pushing the micro-motion trigger piece 223 to bend downward by 0.2mm, triggering the alarm contact to close. The expansion strip changes color for secondary confirmation, and the leakage alarm is completed within a few seconds, preventing insulation degradation, corrosion, or short circuit.

[0098] The internal pressure of the relay increases, the bellows 141 expands, the contact area between the heat-conducting sleeve 142 and the phase change thermistor cavity 143 increases, the phase change liquid vaporizes and absorbs heat, the bimetallic disc 144 jumps suddenly, and the linkage rod 145 moves downward.

[0099] Level 1: When the conductive disk 1451 and the elastic contact finger 1452 are closed, the alarm can be reset;

[0100] Level 2: The low-melting-point alloy gasket 1453 melts, the elastic contact finger 1452 is permanently locked, and the output continues until manually reset.

[0101] It completes the "sensing-triggering-alarm" process within 2-3 seconds, and is suitable for closed high-voltage DC systems, achieving dual protection of recoverable or irreversible protection.

[0102] The above describes the entire working principle of this invention.

[0103] In this invention, the installation, connection or setting methods of all the components mentioned above are common mechanical methods, and the specific structure, model and coefficient index of all the components are their own technologies. As long as they can achieve their beneficial effects, they can be implemented, so they will not be described in detail.

[0104] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

[0105] In this invention, unless otherwise stated, directional terms such as "up, down, left, right, front, back, inside, outside, and vertical and horizontal" in the terminology only represent the orientation of the term in its conventional use or are common terms understood by those skilled in the art, and should not be regarded as limitations on the term. At the same time, numerals such as "first," "second," and "third" do not represent specific quantities or orders, but are merely used to distinguish names. Moreover, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

Claims

1. A DC power relay capable of rapid alarm, comprising a quick-connect electromagnetic drive module (1) and a composite function base (2), characterized in that, One end of the quick-connect electromagnetic drive module (1) is laterally inserted into the composite functional base (2). The composite functional base (2) includes a main terminal block (21) and a gas-liquid intrusion alarm module (22) disposed at the end away from the quick-connect electromagnetic drive module (1). An overheat alarm module (23) is inserted into one side of the gas-liquid intrusion alarm module (22), and an overpressure / overcurrent alarm module (24) is inserted into the bottom position of the overheat alarm module (23). The gas-liquid intrusion alarm module (22) includes two sets of oppositely opened ventilation slits (221), and an expansion cavity (222) is opened at the interval between the two sets of opposite ventilation slits (221). A micro-motion trigger piece (223) is provided at the bottom of the inner end face of the ventilation slit (221). The overheat alarm module (23) includes a thermal frame (231) and bimetallic cavities (232) respectively opened at the middle position of the two end faces of the thermal frame (231). Thermal trigger sliders (233) are installed on both sides of the inner cavity of the thermal frame (231), and overheat alarm contacts (234) are inserted at the interval between the two sets of thermal trigger sliders (233). The overvoltage / overcurrent alarm module (24) includes a main contact (241) and a buzzer cavity (242) disposed on the side end face of the main contact (241). A sliding guide rail (243) is arranged laterally on one side of the buzzer cavity (242). Sliding slider arms (244) are slidably disposed on both sides of the side end face of the sliding guide rail (243). Multiple sliding slider arms (244) are arranged and connected. One end of each sliding slider arm (244) is installed. Two sets of sliding slider arms (244) arranged opposite to each other are connected by an elastic linkage (245). The gap between the two sets of elastic linkages (245) is connected by a quick-closing contact (246). The quick-connect electromagnetic drive module (1) includes an insulating shell (11) and a moving iron core guide rod (12) that passes through the inner cavity of the insulating shell (11). Side latches (13) are installed on both sides of the edge of the insulating shell (11). A pressure-overheat alarm (14) is vertically inserted into the groove of the side latches (13). The pressure-overheat alarm (14) includes a bellows (141) and a heat-conducting sleeve (142) installed on the outer ring of the bellows (141). A phase change thermistor (143) is sleeved on the outer ring of the heat-conducting sleeve (142). One end of a bimetallic disc (144) is installed on both sides of the outer ring of the phase change thermistor (143), and a linkage rod (145) is provided on the other end of the bimetallic disc (144).

2. A DC power relay capable of rapid alarm according to claim 1, characterized in that, The main terminal block (21) includes a terminal body (211) and insert slots (212) arranged on one side end face of the terminal body (211), and locking holes (213) are arranged on the side end face of the terminal body (211).

3. A DC power relay capable of rapid alarm according to claim 2, characterized in that, The locking hole (213) is inserted through the inner cavity of the moving iron core guide rod (12), so that the quick-connect electromagnetic drive module (1) and the composite functional base (2) are combined into a whole.

4. A DC power relay capable of rapid alarm according to claim 1, characterized in that, The linkage rod (145) includes a conductive disk (1451) and elastic contact fingers (1452) installed on both sides of the conductive disk (1451). A low melting point alloy gasket (1453) is sandwiched between the two sets of elastic contact fingers (1452).

5. A DC power relay capable of rapid alarm according to claim 4, characterized in that, The two sets of elastic contact fingers (1452) are connected in series through a series output terminal (146).

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