Frequency converter and sudden stop control system
By introducing emergency stop modules and frequency modulation modules into the inverter, the circuit breaker is controlled by linkage of normally closed contacts and undervoltage trippers, and the emergency stop signal is directly sent to the control board, which solves the problem of insufficient emergency stop reliability of the inverter and achieves fast and reliable emergency stop.
Patent Information
- Application Number
- CN202411726047.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-28
- Publication Date
- 2025-07-25
AI Technical Summary
The existing emergency shutdown method has the problem of insufficient reliability in the frequency converter, especially when the contacts of the start signal contactor are stuck in time.
A frequency converter is designed, including a control board, a circuit breaker, an emergency stop module and a frequency modulation module. The emergency stop module controls the circuit breaker to be disconnected through a normally closed contact and an undervoltage tripper, and directly sends an emergency stop signal to the control board. The frequency modulation module adjusts the voltage and frequency according to the driving signal. The control board executes an emergency stop program to achieve an emergency stop without relying on the upper computer.
It improves the reliability of the inverter emergency shutdown, reduces the risk of untimely or incorrect operation, ensures that the power supply and control signals are quickly cut off in abnormal situations, and achieves reliable emergency shutdown.
Smart Images
Figure CN120377188A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of frequency converter control technology. Specifically, it relates to a frequency converter and an emergency stop control system. Background Art
[0002] A frequency converter can control the operation of an electric motor by changing the frequency of the power supply, thereby realizing functions such as speed regulation, energy saving, and protection, and is widely used in fields such as electric power, chemical industry, and building materials. With the development of frequency converter control technology, the timeliness and reliability of frequency converter protection have become increasingly important. Currently, an emergency stop button is usually set on the upper computer control cabinet to achieve emergency shutdown. Specifically, when an abnormality occurs in the unit, the emergency stop button is pressed to control the power failure of the upper computer control cabinet, and the start signal of the frequency converter is disconnected due to the power failure of the upper computer, thereby achieving the purpose of controlling the frequency converter to stop. This method is simple to implement, but if the contact of the contactor for the start signal is stuck, it will cause the frequency converter to fail to stop in time. Therefore, the above-mentioned emergency shutdown method has the disadvantage of being unreliable.
[0003] Correspondingly, a new frequency converter is needed in this field to solve the above problems. Summary of the Invention
[0004] In order to overcome the above defects, this application is proposed to solve or at least partially solve the problem of insufficient reliability of the existing emergency shutdown method.
[0005] In a first aspect, a frequency converter is provided, including: a control board; a circuit breaker; an emergency stop module; a frequency modulation module, wherein the input side of the frequency modulation module is connected to a three-phase power supply through the circuit breaker, the output side of the frequency modulation module is connected to an electromechanical device, and the frequency modulation module is configured to receive a driving signal sent by the control board and adjust the voltage and frequency of the three-phase power supply delivered to the electromechanical device according to the driving signal, wherein the emergency stop module is configured to control the circuit breaker to disconnect and send an emergency stop signal to the control board.
[0006] In a technical solution of the above frequency converter, the emergency stop module includes: an emergency stop button; a switching power supply; an under-voltage release, wherein the under-voltage release includes a coil and a tripping mechanism, the coil, the emergency stop button, and the switching power supply are connected end to end in sequence to form a series circuit, wherein the emergency stop button uses a normally closed contact, and the tripping mechanism is linked with the circuit breaker and is configured to control the circuit breaker to disconnect when the coil loses power.
[0007] In a technical solution of the above frequency converter, the emergency stop button is normally in a popped-up state. When the emergency stop button is pressed, the normally closed contact is disconnected, and the emergency stop button is configured to feedback the information that the normally closed contact is disconnected to the control board as an emergency stop signal.
[0008] In a technical solution of the above frequency converter, the input side of the frequency modulation module includes: a rectification unit for converting the alternating current provided by the three-phase power supply into direct current; the output side of the frequency modulation module includes: an inversion unit for converting the direct current into alternating current with a target voltage and frequency according to the drive signal.
[0009] In a technical solution of the above frequency converter, the control board is powered by the direct current converted by the rectification unit.
[0010] In a technical solution of the above frequency converter, there are a buffer unit and a filtering unit. The filtering unit is used for smoothing the direct current, and the buffer unit is used for limiting the inrush current generated at the moment when the circuit breaker closes.
[0011] In a technical solution of the above frequency converter, the buffer unit includes a buffer resistor and a contactor. The buffer resistor is connected in series between the rectification unit and the inversion unit to limit the inrush current, and the contactor is connected in parallel across the buffer resistor and is used to short-circuit the buffer resistor when closed.
[0012] In a technical solution of the above frequency converter, there are multiple switching devices for receiving the drive signal and conducting or turning off according to the drive signal.
[0013] In a technical solution of the above frequency converter, the control board is further used to adjust the drive signal according to the emergency stop signal to control the multiple switching devices to turn off.
[0014] In a second aspect, an emergency stop control system is provided. The system includes: a host computer and the frequency converter in the first aspect or any corresponding technical solution thereof. The host computer is used for continuously outputting a start signal to the control board. The start signal is used to control the frequency converter and the electromechanical equipment to start and run. The host computer is further used for stopping outputting the start signal to the control board when the emergency stop signal is obtained.
[0015] One or more of the above technical solutions of the present application have at least one or more of the following beneficial effects:
[0016] In implementing the technical solution of the present application, the emergency stop module of the frequency converter can control the circuit breaker to disconnect, thereby cutting off the power supply of the three-phase power supply to the frequency converter. And the emergency stop module realizes the purpose of feeding back the emergency stop information to the control board by sending an emergency stop signal to the control board. The control board can execute the emergency stop program, and the frequency converter can achieve the purpose of reliable shutdown without relying on the host computer.
[0017] In implementing the technical solution of this application, the emergency stop button uses normally closed contacts to ensure that the power supply can be immediately cut off when the emergency stop button is pressed, reducing the risk of untimely or incorrect operation and further improving the reliability of the emergency shutdown of the frequency converter.
[0018] In implementing the technical solution of this application, the control board receives the emergency stop signal and adjusts the drive signal according to the emergency stop signal to control the shutdown of multiple switching devices included in the inverter, effectively cutting off the output of the frequency converter to the electromechanical equipment and further improving the reliability of the emergency shutdown of the frequency converter.
[0019] In implementing the technical solution of this application, the above-mentioned frequency converter and the upper computer are used as the emergency stop control system. In addition to the frequency converter itself being able to achieve emergency shutdown, the upper computer can also receive the emergency stop signal, thereby stopping the output of the start signal to the control board. Compared with the traditional method of sending an emergency stop signal from the upper computer to the frequency converter for emergency shutdown, this emergency stop control system is faster and more reliable. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The drawings herein are incorporated into and constitute a part of this specification, showing embodiments consistent with this application and used together with the specification to explain the principles of this application.
[0021] To more clearly illustrate the technical solutions in the embodiments of this application or in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.
[0022] Figure 1 is a schematic diagram of the hardware environment of an interaction method of an intelligent device according to an embodiment of this application;
[0023] Figure 2 is a schematic block diagram of the structure of a frequency converter according to an embodiment of this application;
[0024] Figure 3 is a schematic block diagram of the structure of an emergency stop module according to an embodiment of this application;
[0025] Figure 4 is a schematic block diagram of the structure of a frequency modulation module according to an embodiment of this application;
[0026] Figure 5 is a schematic block diagram of the structure of a frequency modulation module according to another embodiment of this application;
[0027] Figure 6 is a schematic block diagram of the structure of an emergency stop control system according to an embodiment of this application;
[0028] Figure 7It is a schematic diagram of the overall structure of an emergency stop control system according to an embodiment of the present application.
[0029] Reference numerals:
[0030] 0: Inverter; 1: Control board; 2: Circuit breaker; 3: Emergency stop module; 4: Frequency modulation module; 5: Host computer; 30: Emergency stop button; 31: Switching power supply; 32: Under-voltage release; 320: Coil of the under-voltage release; 321: Tripping mechanism of the under-voltage release; 41: Rectifying unit; 42: Inverting unit; 43: Filtering unit; 44: Buffering unit. Detailed implementation manners
[0031] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.
[0032] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily need to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices. The terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can also be the internal communication of two components. It can be a wireless connection or a wired connection.
[0033] The terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation of the present invention. In addition, "module" and "processor" may include hardware, software or a combination of the two. A module may include hardware circuits, various suitable sensors, communication ports, and memory, and may also include software parts, such as program code, or a combination of software and hardware. The processor may be a central processing unit, a microprocessor, an image processor, a digital signal processor or any other suitable processor. The processor has data and / or signal processing functions. The processor may be implemented in software, hardware or a combination of the two. Computer-readable storage media include any suitable medium that can store program code, such as a disk, a hard disk, an optical disk, a flash memory, a read-only memory, a random access memory, and the like.
[0034] In addition, if the meaning of "and / or" appears in this application, it includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or a solution that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this application. The term "at least one A or B" or "at least one of A and B" has a similar meaning to "A and / or B" and can include only A, only B, or A and B. The singular terms "one" and "this" can also include plural forms.
[0035] According to one aspect of an embodiment of the present application, a method for interacting with a smart home device is provided. The method for interacting with a smart home device is widely used in smart home, smart home, smart home device ecosystem, smart home ecosystem and other whole-house intelligent digital control application scenarios. Optionally, in this embodiment, the method for interacting with the smart home device can be applied to Figure 1 In the hardware environment composed of the terminal device 102 and the server 104 shown in FIG. Figure 1As shown, the server 104 is connected to the terminal device 102 through a network and can be used to provide services (such as application services, etc.) for the terminal or the client installed on the terminal. A database can be set up on the server or independently of the server to provide data storage services for the server 104. Cloud computing and / or edge computing services can be configured on the server or independently of the server to provide data operation services for the server 104.
[0036] The above network can include but is not limited to at least one of the following: wired network, wireless network. The above wired network can include but is not limited to at least one of the following: wide area network, metropolitan area network, local area network. The above wireless network can include but is not limited to at least one of the following: WIFI (Wireless Fidelity), Bluetooth. The terminal device 102 is not limited to a PC, mobile phone, tablet computer, smart air conditioner, smart range hood, smart refrigerator, smart oven, smart stove, smart washing machine, smart water heater, smart washing equipment, smart dishwasher, smart projection device, smart TV, smart drying rack, smart curtain, smart audio and video, smart socket, smart speaker, smart sound box, smart fresh air device, smart kitchen and bathroom equipment, smart bathroom equipment, smart floor sweeping robot, smart window cleaning robot, smart mopping robot, smart air purification device, smart steam box, smart microwave oven, smart kitchen water heater, smart purifier, smart water dispenser, smart door lock, etc.
[0037] With the development of HVAC central air conditioning technology, the frequency conversion of central air conditioners has become a trend, and higher requirements are also put forward for the timeliness and reliability of the protection of frequency converters (variable frequency drives). It is usually required that central air conditioners, especially chilled water unit central air conditioners, need to have an emergency stop function to face sudden emergency abnormal situations and avoid losses. The traditional emergency stop control method sets an emergency stop button on the upper computer control cabinet. When the unit has an abnormality, the emergency stop button is pressed, and the upper computer control cabinet loses power, and the start signal of the frequency converter is disconnected due to the power loss of the upper computer, so that the frequency converter stops. This method is simple and effective, but there are disadvantages of being unreliable. For example, if the contact of the start signal contactor of the upper computer sticks, it will cause the frequency converter to fail to stop in time, resulting in the deterioration of the abnormality.
[0038] In view of the above problems, this embodiment provides a frequency converter. Refer to the attached Figure 2 , Figure 2 is a schematic structural block diagram of a frequency converter according to an embodiment of the present application.
[0039] As Figure 2As shown in the figure, the frequency converter 0 includes: a control board 1, a circuit breaker 2, an emergency stop module 3, and a frequency modulation module 4. Among them, the input side of the frequency modulation module 4 is connected to a three-phase power supply via the circuit breaker 2, and the output side of the frequency modulation module 4 is connected to the electromechanical equipment. The electromechanical equipment includes: equipment such as motors and compressors. The frequency modulation module 4 is used to receive the drive signal sent by the control board 1 and adjust the voltage and frequency of the three-phase power supply delivered to the electromechanical equipment. The emergency stop module 3 is used to control the circuit breaker 2 to disconnect and send an emergency stop signal to the control board 1. It should be noted that in the event of an abnormal situation, the power supply of the frequency converter can be cut off by controlling the circuit breaker 2 to disconnect through the emergency stop module 3. At the same time, the emergency stop module 3 sends an emergency stop signal to the control board 1, thereby feeding back the emergency stop information to the control board. When the control board 1 receives the emergency stop signal, it can execute the pre-set emergency stop program. The frequency converter provided in this embodiment can achieve emergency shutdown under abnormal conditions without relying on the upper computer, and has the advantages of fast speed and reliability.
[0040] In an alternative embodiment, as Figure 3 shown, the emergency stop module 3 includes: an emergency stop button 30, a switching power supply 31, and an under-voltage release 32. Specifically, the under-voltage release 32 includes a coil 320 and a tripping mechanism 321. The coil 320, the emergency stop button 30, and the switching power supply 31 are connected end to end in sequence to form a series circuit. Among them, the emergency stop button 30 uses a normally closed contact, and the tripping mechanism 321 is linked with the circuit breaker and is used to control the circuit breaker to disconnect when the coil loses power.
[0041] It can be understood that the contacts of the emergency stop button are in a closed and popped state under normal conditions, the coil of the under-voltage release is energized, and the circuit breaker is closed. When an abnormal situation occurs, press the emergency stop button, the normally closed contacts of the emergency stop button will disconnect, the coil of the under-voltage release will lose power, and the circuit breaker will disconnect.
[0042] In one embodiment, the coil of the under-voltage release can be placed inside the circuit breaker.
[0043] In one embodiment, in the event of an abnormal situation, the normally closed contacts of the emergency stop button can be disconnected through a program, so as to achieve the purpose of remotely controlling the frequency converter to stop.
[0044] In this embodiment, the emergency stop button uses a normally closed contact, which achieves the purpose of ensuring that the power supply can be immediately cut off when the emergency stop button is pressed, reduces the risk of untimely operation or misoperation, and further improves the reliability of the emergency shutdown of the frequency converter.
[0045] In an alternative embodiment, the emergency stop button is in a popped state under normal conditions. When the emergency stop button is pressed, the normally closed contacts will disconnect, and the emergency stop button will feed back the information that the normally closed contacts are disconnected as an emergency stop signal to the control board.
[0046] In one embodiment, after the control board obtains an emergency stop signal, it can execute a pre-set emergency stop program, such as cutting off the output of the frequency converter.
[0047] In an alternative embodiment, as Figure 4 shown, the input side of the frequency modulation module 4 includes: a rectification unit 41, where the rectification unit 41 is used to convert the alternating current provided by the three-phase power supply into direct current. The output side of the frequency modulation module 4 includes: an inversion unit 42, and the inversion unit 42 is used to convert the direct current into alternating current with a target voltage and frequency according to the drive signal, and then deliver it to the electromechanical device. Among them, the rectification unit and the inversion unit can use the rectification circuit and the inversion circuit in the prior art, which will not be elaborated here.
[0048] In an alternative embodiment, the control board of the frequency converter can be powered by the direct current converted by the rectification unit.
[0049] In an alternative embodiment, as Figure 5 shown, the frequency modulation module 4 further includes: a filtering unit 43 and a buffer unit 44, where the filtering unit 43 is used to smooth the direct current, and the buffer unit 44 is used to limit the inrush current generated at the moment when the circuit breaker closes.
[0050] In one embodiment, the buffer unit includes a buffer resistor and a contactor. The buffer resistor is connected in series between the rectification unit and the inversion unit to limit the inrush current, and the contactor is connected in parallel across the buffer resistor to short-circuit the buffer resistor when it closes.
[0051] In one embodiment, the inversion unit includes: a plurality of switching devices, and the plurality of switching devices receive a drive signal and conduct or turn off according to the drive signal. Among them, the switching devices are semiconductor devices such as Insulated-Gate Bipolar Transistor (IGBT) and Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET).
[0052] In one embodiment, taking the switching device as an IGBT as an example, the device can be turned on or off by controlling the gate voltage of the IGBT through a drive signal. Specifically, when the drive signal is a high-level signal, the IGBT conducts, and when the drive signal is a low-level signal, the IGBT turns off.
[0053] In an alternative embodiment, the control board is further configured to adjust the drive signal according to the emergency stop signal to control the plurality of switching devices to turn off. Specifically, when the control board receives an emergency stop signal, it can adjust the drive signal and send a low-level signal to the switching device, so as to turn off the switching device.
[0054] It should be noted that since the frequency modulation module usually includes capacitors, the capacitors may output voltage after power-off. Therefore, by adjusting the drive signal to control the turn-off of multiple switching devices, it is possible to prevent the frequency converter from supplying power to the electromechanical equipment after the power supply is cut off, achieving the effect of further improving the reliability of the emergency stop.
[0055] In the embodiment of the present application, during an emergency stop, on the one hand, the circuit breaker is controlled to disconnect and cut off the power supply of the frequency converter, and on the other hand, multiple switching devices are controlled to turn off, instantaneously blocking the output of the inverter power supply, achieving the purpose of reliably and emergently stopping the frequency converter.
[0056] Another aspect of the present application also provides an emergency stop control system. Refer to the attached Figure 6 , Figure 6 is a schematic structural block diagram of an emergency stop control system according to an embodiment of the present application. As Figure 6 shown, the emergency stop control system includes:
[0057] A host computer 5 and the frequency converter 0 in the first aspect or any corresponding technical solution thereof. The host computer 5 is used to continuously output a start signal to the control board of the frequency converter 0. The start signal is used to control the start and operation of the frequency converter and the electromechanical equipment. The host computer is also used to stop outputting the start signal to the control board when an emergency stop signal is obtained.
[0058] In implementing the technical solution of the present application, the above-mentioned frequency converter and the host computer are used as the emergency stop control system. In addition to the frequency converter itself being able to achieve emergency stop, the host computer can also receive the emergency stop signal, thereby stopping sending the start signal to the control board of the frequency converter. Compared with the traditional method of sending an emergency stop signal from the host computer to the frequency converter for emergency stop, this emergency stop control system is faster and more reliable.
[0059] In an example of an application scenario of the present application, Figure 7 is a schematic overall structure diagram of an emergency stop control system according to an embodiment of the present application. As Figure 7As shown, the frequency converter 0 is respectively connected to a three-phase power supply and a mechanical and electrical device. The frequency converter 0 adjusts the voltage frequency of the three-phase power supply and then transmits it to the mechanical and electrical device. The host computer 5 is communicatively connected to the frequency converter 0. On the one hand, it transmits a start signal to the frequency converter 0, and on the other hand, it receives an emergency stop signal fed back by the frequency converter 0. Specifically, the coil of the under-voltage release, the emergency stop button, and the switching power supply in the emergency stop module 3 form a series circuit. The switching power supply can obtain alternating current from the three-phase power supply that is not connected to the circuit breaker 2 and convert it into direct current to supply power to the coil of the under-voltage release (such as converting 220V alternating current into 24V direct current). The tripping mechanism of the under-voltage release is placed inside the circuit breaker 2. Under normal circumstances, the switching power supply outputs direct current, the emergency stop button is in the popped-up state, and its contacts are closed. At this time, the coil is energized, the circuit breaker can be normally closed, and the frequency converter is normally powered on. When normally powered on, the host computer sends a start signal to the control board, and the control board sends a drive signal to the frequency modulation module 4 according to this start signal to control the operation of the frequency converter and the mechanical and electrical device. Optionally, the host computer can also send a speed signal to the control board, and the control board converts this speed signal into a corresponding drive signal and sends it to the switching device of the inverter power supply of the frequency modulation module 4, thereby realizing Pulse Width Modulation (PWM), that is, by changing the ratio of the conduction time of the switching device to the total time, the purpose of adjusting the voltage and frequency is achieved.
[0060] Exemplarily, the frequency modulation module 4 includes a rectification unit, a buffer unit, a filtering unit, and an inversion unit. Among them, the rectification unit includes six diodes; the buffer unit includes a buffer resistor and a contactor; the filtering unit includes a reactor and a capacitor; the inversion unit includes six switching tubes. Among them, the control board can be powered by the direct current U converted by the rectification unit dc Supply power.
[0061] When the unit has an abnormality and needs to be emergently stopped, press the emergency stop button of the frequency converter. The normally closed contacts of the emergency stop button are disconnected, the coil of the under-voltage release loses power, the circuit breaker trips, and the power supply of the frequency converter is disconnected. In addition, the information that the normally closed contacts of the emergency stop button are disconnected is fed back to the control board and the host computer as an emergency stop signal. The host computer stops sending a start signal to the control board, and the control board executes an emergency stop program, such as sending a low-level signal (drive signal) to the switching device to instantly block the PWM output, achieving the purpose of reliably emergently stopping the frequency converter.
[0062] In this embodiment, by setting an emergency stop button for the frequency converter, the purpose of cutting off the power supply and the control signal (start signal) is achieved, and the effect of reliably emergently stopping the frequency converter is achieved. Compared with the traditional method of sending an emergency control signal command by the host computer to the frequency conversion drive for emergency stop, the reliability is higher.
[0063] It should be noted that although the above embodiments describe the various steps in a specific order, those skilled in the art can understand that in order to achieve the effects of this application, it is not necessary for different steps to be executed in such an order. They can be executed simultaneously (in parallel) or in other orders, and the solutions after these adjustments are equivalent technical solutions to the technical solutions described in this application, and thus will also fall within the protection scope of this application.
[0064] The above are only the preferred embodiments of this application. It should be noted that for those of ordinary skill in the art, without departing from the principle of this application, several improvements and refinements can be made, and these improvements and refinements should also be regarded as within the protection scope of this application.
Claims
1. A frequency converter, characterized in that, Comprising: Control panel; Circuit breaker; Emergency stop module; Frequency modulation module, wherein the input side of the frequency modulation module is connected to a three-phase power supply via the circuit breaker, the output side of the frequency modulation module is connected to the electromechanical equipment, and the frequency modulation module is used to receive the drive signal sent by the control panel and adjust the voltage and frequency of the three-phase power supply delivered to the electromechanical equipment according to the drive signal, wherein the emergency stop module is used to control the circuit breaker to disconnect and send an emergency stop signal to the control panel.
2. The frequency converter according to claim 1, characterized in that, The emergency stop module includes: Emergency stop button; Switching power supply; Under-voltage release, wherein the under-voltage release includes a coil and a tripping mechanism, the coil, the emergency stop button and the switching power supply are connected end to end in sequence to form a series circuit, wherein the emergency stop button uses normally closed contacts, and wherein the tripping mechanism is linked with the circuit breaker and is used to control the circuit breaker to disconnect when the coil loses power.
3. The frequency converter according to claim 2, wherein The emergency stop button is normally in a popped-up state. When the emergency stop button is pressed, the normally closed contacts are disconnected, and the emergency stop button is used to feedback the information that the normally closed contacts are disconnected as an emergency stop signal to the control panel.
4. The frequency converter according to claim 1, wherein The input side of the frequency modulation module includes: Rectification unit, which is used to convert the alternating current provided by the three-phase power supply into direct current; The output side of the frequency modulation module includes: Inversion unit, which is used to convert the direct current into alternating current with a target voltage and frequency according to the drive signal.
5. The frequency converter according to claim 4, wherein The control panel is powered by the direct current converted by the rectification unit.
6. The frequency converter according to claim 4, characterized in that, The frequency modulation module further includes: Buffer unit and filtering unit, wherein the filtering unit is used to smooth the direct current, and the buffer unit is used to limit the inrush current generated at the moment when the circuit breaker closes.
7. The frequency converter according to claim 6, wherein The buffer unit includes a buffer resistor and a contactor, wherein the buffer resistor is connected in series between the rectification unit and the inversion unit to limit the inrush current, and the contactor is connected in parallel across the buffer resistor and is used to short-circuit the buffer resistor when closed.
8. The frequency converter according to claim 4, characterized in that The inversion unit includes: Multiple switching devices, which are used to receive the drive signal and conduct or cut off according to the drive signal.
9. The frequency converter according to claim 8, wherein The control panel is further used to adjust the drive signal according to the emergency stop signal to control the multiple switching devices to cut off.
10. An emergency stop control system, characterized in that, The system includes: Host computer and the frequency converter according to any one of claims 1 to 9 above, wherein the host computer is used to continuously output a start signal to the control panel, wherein the start signal is used to control the start and operation of the frequency converter and the electromechanical equipment, and wherein the host computer is further used to stop outputting the start signal to the control panel when the emergency stop signal is acquired.