Frequency converter and elevator

Abstract

The embodiment of the invention discloses a frequency converter and an elevator. The frequency converter comprises a power supply interface, a brake resistor, a brake module, a first switch, an emergency module and a detection module, so that the state of the brake module can be monitored in real time through the detection module; the emergency module controls the first end and the second end of the first switch to be disconnected according to the fault signal, so as to turn off a main power supply of the frequency converter, effectively block a fault loop, prevent a brake resistor from being burnt due to continuous overheating, and improve the system safety.

Description

Technical Field

[0001] This application relates to the field of elevator control technology, and in particular to a frequency converter and an elevator. Background Technology

[0002] In elevator control systems, the frequency converter serves as the core drive unit, responsible for regulating the motor's operating status. When the elevator is descending or decelerating, the motor may enter generator mode, producing excess electrical energy. This excess energy is typically converted using a combination of braking resistors and brake tubes to dissipate the energy.

[0003] However, when the brake tube is damaged (e.g., a short-circuit fault), a continuous conducting loop is formed from the positive terminal of the bus, the brake resistor, the faulty brake tube, the soft-start circuit to the negative terminal of the bus. This causes the brake resistor to carry a large current for a long time, resulting in a continuous increase in temperature and eventually causing the resistor to burn out and an accident to occur. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this application provides a frequency converter and elevator that can monitor the status of the braking module in real time and promptly cut off the main power supply when a fault occurs, preventing the braking resistor from overheating and burning out, thereby improving the safety of the system.

[0005] To address the aforementioned problems, in a first aspect, this application provides a frequency converter, comprising: Power supply interface; one end of the power supply interface is connected to the mains power. Braking resistor, one end of which is connected to the first busbar and configured to consume the generated energy of the motor where the frequency converter is located; The braking module has its first end connected to the other end of the braking resistor to form a detection node, and its second end connected to the second busbar. The braking module is configured to control the on / off state of the braking resistor. The first switch has its first end connected to the other end of the power supply interface, and its second end connected to the first busbar and the second busbar respectively. The emergency module is connected to the third terminal of the first switch and is configured to supply power to the frequency converter in the event of a mains power outage or undervoltage. The detection module has one end connected to the detection node and the other end connected to the feedback end of the emergency module. Specifically, when the detection module outputs a fault signal from the braking module to the feedback terminal of the emergency module, the emergency module controls the first and second terminals of the first switch to disconnect based on the fault signal.

[0006] In one embodiment, the power supply interface includes a first pin, a second pin, and a third pin; the first switch includes a first relay, a second relay, and a third relay; and the frequency converter also includes a connector. The first relay includes a first sub-switch and a first coil; the second relay includes a second sub-switch and a second coil; and the third relay includes a third sub-switch and a third coil. The first contact of the first sub-switch is connected to the first pin, the first contact of the second sub-switch is connected to the second pin, the first contact of the second sub-switch is connected to the third pin, the second contact of the first sub-switch, the second contact of the second sub-switch and the second contact of the third sub-switch are all connected to one end of the connector, and the other end of the connector is connected to the first busbar and the second busbar. One end of the first coil, one end of the second coil, and one end of the third coil are all connected to the emergency module, and the other ends of the first coil, the second coil, and the third coil are all connected to the first voltage source.

[0007] In one embodiment, the emergency module includes a backup battery and a switching power supply; The backup battery is connected to one end of the switching power supply, and the other end of the switching power supply is connected to the third contact of the first sub-switch, the third contact of the second sub-switch, and the third contact of the third sub-switch. When the mains power fails or is undervoltage, the second and third contacts of the first sub-switch, the second and third contacts of the second sub-switch, and the second and third contacts of the third sub-switch are connected, and the backup battery provides temporary power to the inverter based on the switching power supply. When the detection module outputs a fault signal of the braking module to the feedback terminal of the emergency module, the emergency module outputs a first signal to the third terminal of the first switch according to the fault signal. The first and second contacts of the first sub-switch, the first and second contacts of the second sub-switch, and the first and second contacts of the third sub-switch are disconnected, and the second and third contacts of the first sub-switch, the second and third contacts of the second sub-switch, and the second and third contacts of the third sub-switch are connected to cut off the power supply to the inverter.

[0008] In one embodiment, the frequency converter further includes a second switch; The first terminal of the second switch is connected to the third terminal of the first switch, the second terminal of the second switch is grounded, and the third terminal of the second switch is connected to the emergency module. When the detection module outputs a fault signal from the braking module to the feedback terminal of the emergency module, the emergency module controls the first and second terminals of the second switch to conduct according to the fault signal, thereby controlling the first and second terminals of the first switch to disconnect.

[0009] In one embodiment, the second switch includes a MOSFET and a transistor; In this configuration, the drain of the MOSFET is connected to the third terminal of the first switch, the source of the MOSFET is grounded, the gate of the MOSFET is connected to the collector of the transistor and connected to the second voltage source, the base of the transistor is connected to the emergency module, and the emitter of the transistor is grounded.

[0010] In one embodiment, the frequency converter also includes a main control module; One end of the main control module is connected to the detection module, and the other end of the main control module is connected to the feedback end of the emergency module.

[0011] In one embodiment, the frequency converter further includes a rectifier circuit, a filter circuit, and an inverter circuit; The first end of the rectifier circuit is connected to the second end of the first switch. The second end of the rectifier circuit, one end of the filter circuit, and one end of the inverter circuit are all connected to the first bus. The third end of the rectifier circuit, the other end of the filter circuit, and the other end of the inverter circuit are all connected to the second bus. The control end of the inverter circuit is connected to the main control module.

[0012] In one embodiment, the rectifier circuit includes a first diode, a second diode, a third diode, a fourth diode, a fifth diode, and a sixth diode; the filter circuit includes a first capacitor and a second capacitor; and the inverter circuit includes a first insulated-gate bipolar transistor, a second insulated-gate bipolar transistor, a third insulated-gate bipolar transistor, a fourth insulated-gate bipolar transistor, a fifth insulated-gate bipolar transistor, and a sixth insulated-gate bipolar transistor. The anode of the first diode is connected to the second terminal of the first switch and the cathode of the second diode, the anode of the third diode is connected to the second terminal of the first switch and the cathode of the fourth diode, the anode of the fifth diode is electrically connected to the second terminal of the first switch and the cathode of the sixth diode, the cathodes of the first diode, the third diode, and the fifth diode are all connected to the first busbar, and the anodes of the second diode, the fourth diode, and the sixth diode are all connected to the second busbar. One end of the first capacitor is connected to the first busbar, the other end of the first capacitor is connected to one end of the second capacitor, and the other end of the second capacitor is connected to the second busbar. The collectors of the first, third, and fifth insulated-gate bipolar transistors are all connected to the first busbar. The emitters of the second, fourth, and sixth insulated-gate bipolar transistors are all connected to the second busbar. The emitter of the first insulated-gate bipolar transistor is connected to the collector of the second insulated-gate bipolar transistor and the motor, respectively. The emitter of the third insulated-gate bipolar transistor is connected to the collector of the fourth insulated-gate bipolar transistor and the motor, respectively. The emitter of the fifth insulated-gate bipolar transistor is connected to the collector of the sixth insulated-gate bipolar transistor and the motor, respectively. The gates of the first, second, third, fourth, fifth, and sixth insulated-gate bipolar transistors are all connected to the main control module; or / and, The braking module includes a seventh insulated-gate bipolar transistor (IGBT). The collector of the IGBT is connected to the detection node, the emitter of the IGBT is connected to the second bus, and the gate of the IGBT is connected to the main control module.

[0013] In one embodiment, the frequency converter further includes a seventh diode; In this configuration, the positive terminal of the seventh diode is connected to the detection node, and the negative terminal of the seventh diode is connected to the first busbar; or / and, The detection module includes an optocoupler. The first end of the optocoupler is connected to a third voltage source, the second end of the optocoupler is connected to the detection node, the third end of the optocoupler is connected to a fourth voltage source, and the fourth end of the optocoupler is connected to the feedback terminal of the emergency module and grounded.

[0014] Secondly, this application also provides an elevator that includes the frequency converter provided in the first aspect.

[0015] The frequency converter provided in this application includes a power supply interface, a braking resistor, a braking module, a first switch, an emergency module, and a detection module. One end of the power supply interface is connected to the mains power, and one end of the braking resistor is connected to the first bus and configured to consume the generated energy of the motor where the frequency converter is located. The first end of the braking module is connected to the other end of the braking resistor to form a detection node, and the second end of the braking module is connected to the second bus. The braking module is configured to control the on / off state of the braking resistor. The first end of the first switch is connected to the other end of the power supply interface, and the second end of the first switch is connected to the first bus and the second bus respectively. The emergency module is connected to the third end of the first switch and is configured to supply power to the frequency converter when the mains power is interrupted or undervoltage occurs. One end of the detection module is connected to the detection node, and the other end of the detection module is connected to the feedback terminal of the emergency module. Thus, the status of the braking module can be monitored in real time through the detection module. When the detection module outputs a fault signal of the braking module to the feedback terminal of the emergency module, the emergency module controls the first and second ends of the first switch to disconnect according to the fault signal, thereby shutting off the main power supply of the frequency converter, effectively blocking the fault circuit, preventing the braking resistor from overheating and burning out, and improving system safety. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic block diagram of a frequency converter provided in an embodiment of this application; Figure 2 A first circuit diagram of a frequency converter provided in an embodiment of this application; Figure 3 A second circuit diagram of a frequency converter provided in an embodiment of this application; Figure 4 A circuit diagram of the detection module provided in the embodiments of this application; Figure 5 A schematic block diagram of an elevator provided in an embodiment of this application.

[0018] Figure label: 1. Elevator; 10. Frequency converter; 110. Power supply interface; 120. Braking resistor; 130. Braking module; 140. First switch; 150. Emergency module; 160. Detection module; 170. Mains power; 180. Main control module; 191. First busbar; 192. Second busbar; 210. Connector; 220. Second switch; 230. Rectifier circuit; 240. Filter circuit; 250. Inverter circuit. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0021] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0022] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0023] Furthermore, in this application, unless otherwise explicitly specified or limited in the embodiments, the terms "installation," "connection," "joining," and "fixing" appearing in the embodiments should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral part; it can also be a mechanical connection, an electrical connection, etc. Of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication between two components, or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific implementation.

[0024] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, this application provides a frequency converter 10, which includes: Power supply interface 110, one end of power supply interface 110 is connected to AC power 170; Braking resistor 120, one end of which is connected to the first bus 191 and is configured to consume the generated energy of the motor where the frequency converter 10 is located; Braking module 130, the first end of braking module 130 is connected to the other end of braking resistor 120 to form a detection node, the second end of braking module 130 is connected to the second bus 192, and braking module 130 is configured to control the on and off of braking resistor 120. The first switch 140 has a first end connected to the other end of the power supply interface 110, and the second end of the first switch 140 is connected to the first bus 191 and the second bus 192 respectively. Emergency module 150 is connected to the third terminal of first switch 140 and is configured to supply power to inverter 10 when mains power 170 is interrupted or undervoltage. The detection module 160 has one end connected to the detection node and the other end connected to the feedback end of the emergency module 150. When the detection module 160 outputs a fault signal of the braking module 130 to the feedback terminal of the emergency module 150, the emergency module 150 controls the first terminal of the first switch 140 to disconnect from the second terminal according to the fault signal.

[0025] In this embodiment, the power supply interface 110 can be understood as an electrical connection component for introducing external power into the frequency converter 10. The power supply interface 110 can be implemented by a combination of plug and socket or by direct connection through wires.

[0026] The braking resistor 120 can be implemented using resistive elements with high power carrying capacity, such as metal film resistors and wire-wound resistors. The braking resistor 120 converts excess energy generated by the motor into heat energy for dissipation. Specifically, the braking resistor 120 can be... Figure 3 The resistor R1 in the middle.

[0027] The braking module 130 can be composed of switching elements such as relays, contactors or solid-state switches. The braking module 130 can manage the working state of the braking resistor 120 by controlling the on and off of the control circuit.

[0028] The first switch 140 can be implemented using electrical components with switching functions such as electromagnetic relays, solid-state relays, or circuit breakers. The first switch 140 can keep the circuit connected during normal operation and disconnect the circuit in a fault condition.

[0029] The emergency module 150 can be implemented using an uninterruptible power supply system or a backup battery pack in conjunction with an inverter. The emergency module 150 can provide temporary power support when the main power supply is abnormal.

[0030] The detection module 160 can be implemented using detection methods such as voltage detection circuit, current detection circuit or temperature detection circuit, and its main function is to monitor the working status of the braking module 130 in real time.

[0031] Specifically, the fault detection of the braking module 130 in this application can be achieved through various methods, such as monitoring changes in voltage across its terminals, current waveform characteristics, or abnormal temperatures. For example, when a shoot-through fault occurs in the braking module 130, the voltage across its terminals will rapidly drop to near zero, or the current flowing through it will significantly increase, which can then be used as a basis for fault judgment. The control logic of the emergency module 150 can be implemented through hardware circuitry or through an embedded control system. Its core function is to respond promptly to the received fault signal, thereby controlling the disconnection between the first and second terminals of the first switch 140.

[0032] In this application, by setting up a linkage mechanism between the detection module 160 and the emergency module 150, automatic detection and rapid response to faults in the braking module 130 are achieved. When a fault in the braking module 130 is detected, the emergency module 150 can immediately control the first switch 140 to disconnect, thereby cutting off the formation of a dangerous circuit and avoiding the risk of fire caused by overheating of the braking resistor 120 due to continuous power supply. This achieves closed-loop protection from fault detection to power supply isolation, fundamentally blocking the formation of a dangerous circuit and effectively improving system safety. Simultaneously, this application utilizes the elevator's built-in emergency module 150 to protect the frequency converter 10, effectively reducing the cost of the frequency converter.

[0033] In addition, the emergency module 150 can provide backup power to the inverter 10 in the event of a power outage or undervoltage of the mains power 170. Simultaneously, as the core unit for fault response, it receives signals from the detection module 160 and processes them accordingly. One end of the detection module 160 is connected to detection node A to monitor the operating status of the braking module 130 in real time, and the other end is connected to the feedback terminal of the emergency module 150, responsible for transmitting fault information from the braking module 130 to the emergency module 150. When the detection module 160 outputs a fault signal from the braking module 130 to the feedback terminal of the emergency module 150, the emergency module 150 generates a control command based on this signal, disconnecting the first and second terminals of the first switch 140, thereby cutting off the main power circuit.

[0034] In some embodiments, such as Figure 2 As shown, the power supply interface 110 includes a first pin L1, a second pin L2, and a third pin L3; the first switch 140 includes a first relay KJ1, a second relay KJ2, and a third relay KJ3; and the frequency converter 10 also includes a connector 210. Specifically, the first relay KJ1 includes a first sub-switch K1 and a first coil L1; the second relay KJ2 includes a second sub-switch K2 and a second coil L2; and the third relay KJ3 includes a third sub-switch K3 and a third coil L3. The first contact a of the first sub-switch K1 is connected to the first pin L1, and the first contact a of the second sub-switch K2 is connected to... The first contact a of the second pin L2 and the second sub-switch K2 is connected to the third pin L3. The second contact b of the first sub-switch K1, the second contact b of the second sub-switch K2, and the second contact b of the third sub-switch K3 are all connected to one end of the connector 210. The other end of the connector 210 is connected to the first busbar 191 and the second busbar 192. One end of the first coil L1, one end of the second coil L2, and one end of the third coil L3 are all connected to the emergency module 150. The other ends of the first coil L1, the second coil L2, and the third coil L3 are all connected to the first voltage source (+12V).

[0035] In this embodiment, the power supply interface 110 can be implemented using a three-phase plug or terminal block. The first pin L1, the second pin L2, and the third pin L3 correspond to the phases of the three-phase mains power 170, ensuring that each phase is connected independently.

[0036] The first switch 140 can be a composite switching device composed of multiple relays, which realizes phase-by-phase control of the three-phase power supply through three independent relays.

[0037] The first relay KJ1, the second relay KJ2, and the third relay KJ3 each contain a sub-switch and a coil. The sub-switch is used to switch the circuit on and off, and the coil is used to drive the sub-switch to operate.

[0038] The connector 210 can be understood as a conductive component used to collect current. It can be implemented using copper busbars or bus bars, with the purpose of introducing three-phase current into the bus system in a unified manner.

[0039] Specifically, this application achieves full-phase power disconnection under fault conditions through a three-phase independent relay structure. Pins L1, L2, and L3 of the power supply interface 110 are connected to the three-phase mains power 170, providing basic connection points for subsequent phase-by-phase control. The first switch 140 employs a parallel design of three relays, with each relay's sub-switch connected one-to-one to each pin of the power supply interface 110, achieving physical isolation of the three-phase power at the input end. The connector 210 includes pins L1-1, L2-1, and L3-1.

[0040] When the braking module 130 fault signal is triggered, the emergency module 150 simultaneously drives all relay coils to ensure that the three-phase switches are disconnected synchronously, completely blocking the abnormal current path. Connector 210, as a common bus node, connects the second contacts b of the three sub-switches to the first bus 191 and the second bus 192, simplifying the circuit topology and ensuring the synchronicity of the three-phase output, thereby fundamentally eliminating the potential for continuous heating of the braking resistor 120 due to partial phase energization.

[0041] In this application, when the braking module 130 fails, the emergency module 150 can quickly respond and synchronously cut off all phase power supplies, avoiding the defect that traditional single switches cannot ensure full phase cutoff in three-phase systems. It effectively solves the problem that the bus positive-braking resistor 120-braking pipe-soft start circuit-bus negative circuit cannot be properly cut off due to brake tube damage, prevents the risk of fire caused by continuous heating of the braking resistor 120, and significantly improves the safety and reliability of the system.

[0042] In some embodiments, the emergency module 150 includes a backup battery and a switching power supply; wherein the backup battery is connected to one end of the switching power supply, and the other end of the switching power supply is connected to the third contact c of the first sub-switch K1, the third contact c of the second sub-switch K2, and the third contact c of the third sub-switch K3; when the mains power 170 is interrupted or undervoltage occurs, the second contact b and the third contact c of the first sub-switch K1, the second contact b and the third contact c of the second sub-switch K2, and the second contact b and the third contact c of the third sub-switch K3 are connected, and the backup battery provides temporary power to the inverter 10 based on the switching power supply; when the detection module 160 sends a signal to the inverter 10, the backup battery provides temporary power to the inverter 10 based on the switching power supply. When the feedback terminal of the emergency module 150 outputs a fault signal of the braking module 130, the emergency module 150 outputs a first signal to the third terminal of the first switch 140 according to the fault signal. The first contact a and the second contact b of the first sub-switch K1, the first contact a and the second contact b of the second sub-switch K2, and the first contact a and the second contact b of the third sub-switch K3 are disconnected. The second contact b and the third contact c of the first sub-switch K1, the second contact b and the third contact c of the second sub-switch K2, and the second contact b and the third contact c of the third sub-switch K3 are connected to cut off the power supply to the frequency converter 10.

[0043] In this embodiment, the backup battery can be understood as a device capable of storing electrical energy and releasing it when needed, and can be implemented using lithium-ion batteries, lead-acid batteries, or nickel-metal hydride batteries, etc. A switching power supply is a device that converts an input voltage into a stable output voltage, and can be implemented using an AC-DC conversion circuit, a DC-DC conversion circuit, or a linear voltage regulator circuit. This application, through the cooperation of the backup battery and the switching power supply, can ensure that a stable temporary power supply can be provided to the inverter 10 when the mains power 170 is abnormal, and can quickly disconnect the main power path in the event of a fault.

[0044] Specifically, the emergency module 150 achieves precise control of the power supply status of the inverter 10 through a combination of a backup battery and a switching power supply. When the mains power 170 is normal, the first contact a and the second contact b of the first sub-switch K1 remain connected, and the mains power 170 supplies power to the inverter 10 through the first switch 140. When the mains power 170 is interrupted or undervoltage occurs, the second contact b and the third contact c of the first sub-switch K1 are connected, and the backup battery provides temporary power to the inverter 10 through the switching power supply, thereby ensuring the safe operation of the elevator 1 in the event of a power outage. When the detection module 160 detects a fault signal from the braking module 130 and transmits it to the emergency module 150, the emergency module 150 responds immediately, outputting a first signal to the third terminal of the first switch 140, triggering the disconnection action between the first contact a and the second contact b of the first sub-switch K1, and simultaneously connecting the second contact b and the third contact c of the first sub-switch K1.

[0045] Meanwhile, since the emergency module 150 is not activated at this time, the backup battery cannot supply power to the inverter 10, thus completely cutting off the power input path of the inverter 10. This not only effectively blocks the heating circuit of the braking resistor 120, but also avoids the automatic power supply phenomenon caused by the restoration of the mains power 170 by locking the switch state. As a result, the power supply can only be restarted by external manual reset. This fundamentally solves the problem of the braking module 130's failure response being untimely and significantly reduces the risk of fire caused by the continuous heating of the braking resistor 120. It is especially suitable for scenarios with high safety requirements, such as elevator 1.

[0046] Among them, such as Figure 2 As shown, the emergency module 150 has pins L1-0, L2-0 and L3-0. The third contact c of the first sub-switch K1, the third contact c of the second sub-switch K2 and the third contact c of the third sub-switch K3 are respectively connected to pins L1-0, L2-0 and L3-0.

[0047] In some embodiments, such as Figure 2 As shown, the inverter 10 also includes a second switch 220; wherein, the first end of the second switch 220 is connected to the third end of the first switch 140, the second end of the second switch 220 is grounded to GND, and the third end of the second switch 220 is connected to the emergency module 150; when the detection module 160 outputs a fault signal of the braking module 130 to the feedback terminal of the emergency module 150, the emergency module 150 controls the first end and the second end of the second switch 220 to conduct according to the fault signal, so as to control the first end and the second end of the first switch 140 to disconnect.

[0048] In this embodiment, the second switch 220 can be understood as an electronic component that can control the on / off state of a circuit. It can be implemented using devices with switching functions such as relays, MOSFETs, or IGBTs.

[0049] The first terminal of the second switch 220 serves as a signal input terminal, used to receive control signals from the first switch 140; the second terminal of the second switch 220 is grounded to GND, providing a stable reference potential and ensuring the reliability of the control signals; the third terminal of the second switch 220 serves as a control terminal, used to receive control commands issued by the emergency module 150.

[0050] Specifically, this application constructs a reliable fault state latching mechanism by introducing a second switch 220. The first terminal of the second switch 220 is connected to the third terminal of the first switch 140, thereby directly intervening in the control signal path of the first switch 140. When the detection module 160 detects a fault in the braking module 130 and sends a fault signal to the emergency module 150, the emergency module 150 will immediately respond and trigger the second switch 220 to operate. At this time, a conductive path is formed between the first and second terminals of the second switch 220, forcibly pulling the control terminal of the first switch 140 down to ground potential, thereby ensuring that the first switch 140 is reliably disconnected. Thus, once the second switch 220 is turned on, the ground GND path formed will continue to exist, and even if the fault signal disappears or the system undergoes a power-on process, the disconnected state of the first switch 140 will remain unchanged.

[0051] In this application, by introducing a second switch 220, an automatic fault state saving function is realized, effectively preventing the risk of fire that may be caused by the braking resistor 120 continuously being energized and heating up during a fault state. Simultaneously, the second switch 220, together with components such as the power supply interface 110, the braking module 130, and the first switch 140, forms a complete protection mechanism, ensuring that the system can only be restored by external manual reset, significantly improving the safety and reliability of the inverter 10 in the event of a brake module 130 failure.

[0052] Furthermore, in some embodiments, such as Figure 2 As shown, the second switch 220 includes a MOSFET Q1 and a transistor Q2; wherein, the drain of the MOSFET Q1 is connected to the third terminal of the first switch 140, the source of the MOSFET Q1 is grounded to GND, the gate of the MOSFET Q1 is connected to the collector of the transistor Q2 and connected to the second voltage source 5V_A, the base of the transistor Q2 is connected to the emergency module 150, and the emitter of the transistor Q2 is grounded to GND.

[0053] In this embodiment, MOSFET Q1 can be implemented using an enhancement-mode or depletion-mode MOSFET, and transistor Q2 can be implemented using an NPN or PNP transistor. The second voltage source 5V_A can be understood as a power supply device that provides the drive voltage to the gate of MOSFET Q1. It can be implemented using an independent regulated power supply or a voltage divider circuit, with the purpose of ensuring that the MOSFET can reliably turn on and off.

[0054] Among them, a resistor R4 is provided between the source and gate of MOSFET Q1, a resistor R2 is provided between the second voltage source 5V_A and the gate of MOSFET Q1, a resistor R3 is provided between the second voltage source 5V_A and the pin PLY_1 of emergency module 150, and a resistor R5 is provided between the pin PLY_1 of emergency module 150 and the base of transistor Q2.

[0055] Specifically, when the braking module 130 malfunctions, the emergency module 150 outputs a fault signal to the base of transistor Q2, causing transistor Q2 to quickly enter a saturation conduction state. Since the collector of transistor Q2 is connected to the gate of MOSFET Q1, the gate potential of MOSFET Q1 is pulled low, thus causing MOSFET Q1 to quickly turn on. After MOSFET Q1 turns on, its drain potential is pulled low, directly acting on the control terminal of the first switch 140, ensuring that the first switch 140 can reliably disconnect.

[0056] Meanwhile, the source ground of MOSFET Q1 provides a stable reference potential, preventing malfunctions caused by potential fluctuations during switching and enhancing the circuit's stability in noisy environments. Furthermore, the emitter ground of transistor Q2 forms a complete circuit, ensuring rapid conduction upon fault signal triggering, thereby precisely controlling the operation of MOSFET Q1 and effectively preventing safety hazards caused by the continuous heating of the braking resistor 120.

[0057] In this application, the main power supply can be quickly cut off when the braking module 130 fails, which solves the safety hazards caused by insufficient response speed and reduced reliability in the prior art, and has important application value, especially in the elevator 1 scenario.

[0058] In some embodiments, such as Figure 1 As shown, the frequency converter 10 also includes a main control module 180; one end of the main control module 180 is connected to the detection module 160, and the other end of the main control module 180 is connected to the feedback terminal of the emergency module 150.

[0059] In this embodiment, the main control module 180 can be understood as a core component with signal processing, logic judgment, and control functions. The main control module 180 can be implemented using a microcontroller, a programmable logic controller, or an application-specific integrated circuit. The feedback terminal of the emergency module 150 is connected to the other end of the detection module 160, thereby enabling the raw signal from the detection module 160 to be transmitted to the emergency module 150 through the main control module 180.

[0060] In this application, when the braking module 130 fails, the fault signal generated by the detection module 160 is recorded by the main control module 180, so that the inverter 10 will not supply power to the back end after power failure and power-on. At the same time, the fault signal is transmitted to the emergency module 150 via the main control module 180. The emergency module 150 coordinates the action of the second switch 220 according to the received signal to ensure the accuracy and reliability of the power cut-off process.

[0061] In some embodiments, such as Figure 3As shown, the inverter 10 also includes a rectifier circuit 230, a filter circuit 240, and an inverter circuit 250; wherein, the first end of the rectifier circuit 230 is connected to the second end of the first switch 140, the second end of the rectifier circuit 230, one end of the filter circuit 240, and one end of the inverter circuit 250 are all connected to the first bus 191, the third end of the rectifier circuit 230, the other end of the filter circuit 240, and the other end of the inverter circuit 250 are all connected to the second bus 192, and the control end of the inverter circuit 250 is connected to the main control module 180.

[0062] In this embodiment, the rectifier circuit 230 can be understood as a circuit structure that converts alternating current into direct current. The rectifier circuit 230 can be implemented using a diode bridge rectifier circuit 230 or a silicon controlled rectifier circuit 230, thereby ensuring that the mains power input 170 can be effectively converted into a stable DC voltage to meet the working requirements of subsequent circuits.

[0063] The filter circuit 240 can be a circuit structure used to smooth DC voltage fluctuations. It can be implemented by capacitor filtering, LC filtering or π-type filtering. The filter circuit 240 can eliminate the ripple in the rectified voltage, thereby maintaining the stability of the bus voltage.

[0064] The inverter circuit 250 can be understood as a circuit structure that converts direct current into alternating current. It can be implemented using a three-phase inverter bridge composed of insulated gate bipolar transistors. The inverter circuit 250 can dynamically adjust its output according to the instructions of the main control module 180 to adapt to different operating states of the motor.

[0065] Specifically, by introducing a rectifier circuit 230, a filter circuit 240, and an inverter circuit 250, this application not only achieves effective conversion of the mains power input 170 and stable generation of DC bus voltage, but also reliably handles energy feedback during motor power generation, significantly reducing the risk of abnormal fluctuations in bus voltage.

[0066] Meanwhile, the rectifier circuit 230, filter circuit 240, and inverter circuit 250, combined with the aforementioned power supply interface 110, braking module 130, first switch 140, and emergency module 150, further enhance the system's fault isolation capability and improve overall safety and reliability. The inverter circuit 250 is connected to the motor via pins U, V, and W.

[0067] In some embodiments, such as Figure 3As shown, the rectifier circuit 230 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5, and a sixth diode D6; the filter circuit 240 includes a first capacitor C1 and a second capacitor C2; and the inverter circuit 250 includes a first insulated-gate bipolar transistor U1, a second insulated-gate bipolar transistor U2, a third insulated-gate bipolar transistor U3, a fourth insulated-gate bipolar transistor U4, a fifth insulated-gate bipolar transistor U5, and a sixth insulated-gate bipolar transistor U6.

[0068] In this configuration, the anode of the first diode D1 is connected to the second terminal of the first switch 140 and the cathode of the second diode D2; the anode of the third diode D3 is connected to the second terminal of the first switch 140 and the cathode of the fourth diode D4; the anode of the fifth diode D5 is electrically connected to the second terminal of the first switch 140 and the cathode of the sixth diode D6; the cathodes of the first diode D1, the third diode D3, and the fifth diode D5 are all connected to the first busbar 191; the anodes of the second diode D2, the fourth diode D4, and the sixth diode D6 are all connected to the second busbar 192; one end of the first capacitor C1 is connected to the first busbar 191, and the other end of the first capacitor C1 is connected to one end of the second capacitor C2, which in turn is connected to the second busbar 192; the collectors of the first insulated-gate bipolar transistor U1, the third insulated-gate bipolar transistor U3, and the fifth insulated-gate bipolar transistor U5 are also connected to the second busbar 192. All terminals are connected to the first bus 191. The emitters of the second insulated-gate bipolar transistor U2, the fourth insulated-gate bipolar transistor U4, and the sixth insulated-gate bipolar transistor U6 are all connected to the second bus 192. The emitter of the first insulated-gate bipolar transistor U1 is connected to the collector of the second insulated-gate bipolar transistor U2 and the motor, respectively. The emitter of the third insulated-gate bipolar transistor U3 is connected to the collector of the fourth insulated-gate bipolar transistor U4 and the motor, respectively. The emitter of the fifth insulated-gate bipolar transistor U5 is connected to the collector of the sixth insulated-gate bipolar transistor U6 and the motor, respectively. The gates of the first insulated-gate bipolar transistor U1, the second insulated-gate bipolar transistor U2, the third insulated-gate bipolar transistor U3, the fourth insulated-gate bipolar transistor U4, the fifth insulated-gate bipolar transistor U5, and the sixth insulated-gate bipolar transistor U6 are all connected to the main control module 180.

[0069] In this embodiment, the rectifier circuit 230 can be implemented by using six diodes to form a three-phase full-wave rectifier bridge to ensure smooth bus voltage conversion. The filter circuit 240 can be implemented by connecting the first capacitor C1 and the second capacitor C2 in series between the buses to maintain the stability of the DC bus voltage. The inverter circuit 250 can be implemented by using six insulated-gate bipolar transistors to form a three-phase inverter bridge. By precisely controlling the switching timing, the braking module 130 is coordinated to operate in the motor generating state. This not only solves the problem that the brake module 130 cannot be identified in time when the switching device is damaged and a shoot-through fault occurs, but also improves the safety and reliability of the entire inverter 10 system through the organic cooperation of various circuit modules, especially significantly reducing safety hazards in the scenario of a home elevator 1.

[0070] In some embodiments, such as Figure 4 As shown, the braking module 130 includes a seventh insulated gate bipolar transistor U7. The collector of the seventh insulated gate bipolar transistor U7 is connected to the detection node A, the emitter of the seventh insulated gate bipolar transistor U7 is connected to the second bus 192, and the gate of the seventh insulated gate bipolar transistor U7 is connected to the main control module 180.

[0071] In this embodiment, the braking module 130 can be implemented using a seventh insulated-gate bipolar transistor U7. The main control module 180 monitors the braking tube status in real time and quickly triggers a protection mechanism, achieving active control of the on / off state of the braking resistor 120 and real-time monitoring of voltage changes at detection node A. When the braking tube fails and conducts a short circuit, the voltage at detection node A deviates abnormally from the normal range. The main control module 180 quickly identifies the fault based on gate feedback and outputs a signal to the emergency module 150 to cut off the power supply, thereby preventing the formation of a dangerous circuit.

[0072] The main control module 180 has pins GU+, GU-, GV+, GV-, GW+, GW-, and GB. Pins GU+, GU-, GV+, GV-, GW+, GW-, and GB are respectively connected to the gates of the first insulated gate bipolar transistor U1, the second insulated gate bipolar transistor U2, the third insulated gate bipolar transistor U3, the fourth insulated gate bipolar transistor U4, the fifth insulated gate bipolar transistor U5, the sixth insulated gate bipolar transistor U6, and the seventh insulated gate bipolar transistor U7.

[0073] In some embodiments, such as Figure 4 As shown, the inverter 10 also includes a seventh diode D7; wherein, the positive terminal of the seventh diode D7 is connected to the detection node A, and the negative terminal of the seventh diode D7 is connected to the first bus 191.

[0074] In this embodiment, the seventh diode D7 can automatically turn on when the voltage at the detection node A rises abnormally, clamping the voltage to the level of the first bus 191, thereby avoiding damage to subsequent circuits due to overvoltage surges and preventing false triggering caused by voltage fluctuations.

[0075] Specifically, the positive terminal of the seventh diode D7 is connected to the detection node A, and the negative terminal is connected to the first bus 191. This allows it to quickly conduct when the voltage at the detection node A rises abnormally, limiting the voltage within a safe range. This protects the subsequent circuits from overvoltage surges and effectively avoids false triggering caused by bus voltage fluctuations or electrical noise. It ensures the stability of the detection signal, not only solving the problem that the detection node A is susceptible to interference from bus voltage fluctuations or electrical noise, but also ensuring that the protection mechanism can be accurately triggered when the braking module 130 fails. This eliminates the safety hazard of the braking resistor 120 continuously overheating and catching fire.

[0076] In some embodiments, such as Figure 4 As shown, the detection module 160 includes an optocoupler U8. The first end of the optocoupler U8 is connected to the third voltage source GDN_24V. The second end of the optocoupler U8 is connected to the detection node A. The third end of the optocoupler U8 is connected to the fourth voltage source (+5V). The fourth end of the optocoupler U8 is connected to the feedback terminal of the emergency module 150 and grounded to GND.

[0077] In this embodiment, the optocoupler U8 can be understood as a device that achieves electrical isolation between input and output based on the photoelectric conversion principle. The optocoupler U8 can be implemented using ordinary optocouplers, high-speed optocouplers, or linear optocouplers.

[0078] Specifically, the optocoupler U8 connects to the third voltage source GDN_24V at its first terminal, to the detection node A at its second terminal, to the fourth voltage source (+5V) at its third terminal, and to the BRK_VCE pin of the main control module 180 at its fourth terminal to achieve electrical isolation between the input and output of the emergency module 150. When the braking module 130 fails, the optocoupler U8 can accurately transmit the fault signal to the emergency module 150, ensuring that the emergency module 150 performs the power-off protection operation in a timely manner.

[0079] Among them, a resistor R7 is provided between the detection node A and the second terminal of the optocoupler U8, and a resistor R6 is provided between the second terminal of the optocoupler U8 and the third voltage source GDN_24V; the fourth terminal of the optocoupler U8 is connected to the pin BRK_VCE of the main control module 180 through the resistor R8, and is grounded through the resistor R9.

[0080] In some embodiments, such as Figure 5 As shown, this application also provides an elevator 1, which includes the frequency converter 10 provided in this application.

[0081] In this application, by integrating the frequency converter 10 with the fault detection and emergency protection function of the braking module 130 into the elevator 1 system, the risk of fire caused by overheating of the braking resistor 120 when the braking tube is damaged is fundamentally avoided.

[0082] Specifically, this application incorporates a fault detection mechanism in the inverter 10 of elevator 1, which can trigger emergency protection logic when the braking module 130 malfunctions, automatically cutting off the main power supply and interrupting the continuous power supply circuit of the braking resistor 120. This prevents the fire hazard caused by heat accumulation, ensuring reliable power isolation in fault conditions and avoiding the risk of false triggering of the soft start circuit when power is restored through the fault state memory function. Ultimately, this significantly improves the safety and reliability of elevator 1 operation.

[0083] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A frequency converter, characterized in that, include: A power supply interface, one end of which is connected to mains power; A braking resistor, one end of which is connected to the first busbar and configured to consume the generated energy of the motor where the frequency converter is located; A braking module, wherein a first end of the braking module is connected to the other end of the braking resistor to form a detection node, a second end of the braking module is connected to a second bus, and the braking module is configured to control the on / off state of the braking resistor; A first switch, the first end of which is connected to the other end of the power supply interface, and the second end of which is connected to the first busbar and the second busbar respectively; An emergency module is connected to the third terminal of the first switch and is configured to supply power to the frequency converter when the mains power is interrupted or undervoltage occurs; A detection module, one end of which is connected to the detection node, and the other end of which is connected to the feedback terminal of the emergency module; When the detection module outputs a fault signal of the braking module to the feedback terminal of the emergency module, the emergency module controls the first terminal and the second terminal of the first switch to disconnect according to the fault signal.

2. The frequency converter according to claim 1, characterized in that, The power supply interface includes a first pin, a second pin, and a third pin; the first switch includes a first relay, a second relay, and a third relay; and the frequency converter also includes a connector. Wherein, the first relay includes a first sub-switch and a first coil, the second relay includes a second sub-switch and a second coil, and the third relay includes a third sub-switch and a third coil; The first contact of the first sub-switch is connected to the first pin, the first contact of the second sub-switch is connected to the second pin, the first contact of the second sub-switch is connected to the third pin, the second contact of the first sub-switch, the second contact of the second sub-switch, and the second contact of the third sub-switch are all connected to one end of the connector, and the other end of the connector is connected to the first busbar and the second busbar; One end of the first coil, one end of the second coil, and one end of the third coil are all connected to the emergency module, and the other ends of the first coil, the second coil, and the third coil are all connected to the first voltage source.

3. The frequency converter according to claim 2, characterized in that, The emergency module includes a backup battery and a switching power supply; The backup battery is connected to one end of the switching power supply, and the other end of the switching power supply is connected to the third contact of the first sub-switch, the third contact of the second sub-switch, and the third contact of the third sub-switch. When the mains power is interrupted or undervoltage occurs, the second and third contacts of the first sub-switch, the second and third contacts of the second sub-switch, and the second and third contacts of the third sub-switch are connected, and the backup battery provides temporary power to the inverter based on the switching power supply. When the detection module outputs a fault signal of the braking module to the feedback terminal of the emergency module, the emergency module outputs a first signal to the third terminal of the first switch according to the fault signal, and the first and second contacts of the first sub-switch, the first and second contacts of the second sub-switch, and the first and second contacts of the third sub-switch are disconnected, and the second and third contacts of the first sub-switch, the second and third contacts of the second sub-switch, and the second and third contacts of the third sub-switch are connected to cut off the power supply to the inverter.

4. The frequency converter according to claim 1, characterized in that, It also includes a second switch; Wherein, the first end of the second switch is connected to the third end of the first switch, the second end of the second switch is grounded, and the third end of the second switch is connected to the emergency module; When the detection module outputs a fault signal of the braking module to the feedback terminal of the emergency module, the emergency module controls the first and second terminals of the second switch to conduct according to the fault signal, so as to control the first and second terminals of the first switch to disconnect.

5. The frequency converter according to claim 4, characterized in that, The second switch includes a MOSFET and a transistor; The drain of the MOS transistor is connected to the third terminal of the first switch, the source of the MOS transistor is grounded, the gate of the MOS transistor is connected to the collector of the transistor and connected to the second voltage source, the base of the transistor is connected to the emergency module, and the emitter of the transistor is grounded.

6. The frequency converter according to claim 4, characterized in that, It also includes the main control module; One end of the main control module is connected to the detection module, and the other end of the main control module is connected to the feedback end of the emergency module.

7. The frequency converter according to claim 6, characterized in that, It also includes rectifier circuits, filter circuits, and inverter circuits; The first end of the rectifier circuit is connected to the second end of the first switch. The second end of the rectifier circuit, one end of the filter circuit, and one end of the inverter circuit are all connected to the first bus. The third end of the rectifier circuit, the other end of the filter circuit, and the other end of the inverter circuit are all connected to the second bus. The control end of the inverter circuit is connected to the main control module.

8. The frequency converter according to claim 7, characterized in that, The rectifier circuit includes a first diode, a second diode, a third diode, a fourth diode, a fifth diode, and a sixth diode; the filter circuit includes a first capacitor and a second capacitor; and the inverter circuit includes a first insulated-gate bipolar transistor, a second insulated-gate bipolar transistor, a third insulated-gate bipolar transistor, a fourth insulated-gate bipolar transistor, a fifth insulated-gate bipolar transistor, and a sixth insulated-gate bipolar transistor. The anode of the first diode is connected to the second terminal of the first switch and the cathode of the second diode, the anode of the third diode is connected to the second terminal of the first switch and the cathode of the fourth diode, the anode of the fifth diode is electrically connected to the second terminal of the first switch and the cathode of the sixth diode, the cathodes of the first diode, the third diode, and the fifth diode are all connected to the first busbar, and the anodes of the second diode, the fourth diode, and the sixth diode are all connected to the second busbar. One end of the first capacitor is connected to the first busbar, the other end of the first capacitor is connected to one end of the second capacitor, and the other end of the second capacitor is connected to the second busbar. The collectors of the first, third, and fifth insulated-gate bipolar transistors are all connected to the first busbar. The emitters of the second, fourth, and sixth insulated-gate bipolar transistors are all connected to the second busbar. The emitter of the first insulated-gate bipolar transistor is connected to the collector of the second insulated-gate bipolar transistor and the motor, respectively. The emitter of the third insulated-gate bipolar transistor is connected to the collector of the fourth insulated-gate bipolar transistor and the motor, respectively. The emitter of the fifth insulated-gate bipolar transistor is connected to the collector of the sixth insulated-gate bipolar transistor and the motor, respectively. The gates of the first, second, third, fourth, fifth, and sixth insulated-gate bipolar transistors are all connected to the main control module; or / and, The braking module includes a seventh insulated-gate bipolar transistor (IGBT). The collector of the IGBT is connected to the detection node, the emitter of the IGBT is connected to the second bus, and the gate of the IGBT is connected to the main control module.

9. The frequency converter according to any one of claims 1-8, characterized in that, It also includes the seventh diode; Wherein, the positive terminal of the seventh diode is connected to the detection node, and the negative terminal of the seventh diode is connected to the first busbar; or / and, The detection module includes an optocoupler, the first end of which is connected to a third voltage source, the second end of which is connected to the detection node, the third end of which is connected to a fourth voltage source, and the fourth end of which is connected to the feedback terminal of the emergency module and grounded.

10. An elevator, characterized in that, The inverter includes any one of claims 1-9.

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