A power converter and isolated communication circuit
By using optical fiber to connect isolated communication circuits and conversion circuits, the risks of electric shock and electromagnetic interference caused by strong and weak current isolation in medium and high voltage systems are solved, and safe and reliable signal transmission is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SUNGROW POWER SUPPLY CO LTD
- Filing Date
- 2025-07-31
- Publication Date
- 2026-07-31
AI Technical Summary
In medium and high voltage systems, the current technology relies on the insulation performance of devices to isolate strong and weak currents. This poses a risk of electric shock when high voltage signals are directly transmitted to the safe voltage zone, and the signal transmission is susceptible to electromagnetic interference.
An isolation communication circuit using fiber optic connection converts digital signals between safe voltage and medium-high voltage regions via fiber optic cable, achieving voltage isolation. It also prevents high-voltage signals from being transmitted to the safe voltage region in the event of a short circuit or device failure in the medium-high voltage region. Simultaneously, a conversion circuit is used to perform voltage conversion to adapt to different voltage environments.
This reduces the risk of electric shock to personnel and minimizes the impact of electromagnetic interference on signals, ensuring the reliability of isolated communication.
Smart Images
Figure CN224583085U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of automation control technology, and in particular to a power converter and an isolated communication circuit. Background Technology
[0002] Digital Input (DI) and Digital Output (DO) interfaces are critical signal transmission interfaces in industrial automation control systems. The DI interface receives switching signals from field devices such as buttons and limit switches, while the DO interface outputs control signals to actuators such as relays and solenoid valves. Both DI and DO interfaces typically transmit signals via a 24V connection.
[0003] In medium- and high-voltage systems, the safe voltage zone where the control system is located typically uses DO signals to control high voltage from low voltage. However, this signal control method has many drawbacks. For example, the isolation between high and low voltage relies on the insulation performance of the relevant devices themselves. When these devices are damaged or short-circuited, high voltage may be transmitted directly to the safe voltage zone along the DI and DO signal loops, posing a risk of electric shock to personnel. Summary of the Invention
[0004] To address the aforementioned technical problems in the prior art, this application provides a power converter and an isolated communication circuit that can reduce the risk of electric shock to personnel and reduce the impact of received electromagnetic interference.
[0005] In a first aspect, this application provides a power converter, comprising: a power cabinet, a control cabinet, and one or more isolated communication circuits. The isolated communication circuits include a first module and a second module connected via optical fiber; one of the first and second modules is located in the power cabinet, and the other is located in the control cabinet; the first module is used to connect to a digital signal source, and to convert the digital signal into an optical signal and transmit it to the second module via optical fiber; the digital signal source is a digital input (DI) signal source or a digital output (DO) signal source, the DO signal source is a control system in the control cabinet, and the DI signal source is a device in the power cabinet; the second module is used to convert the optical signal transmitted via optical fiber into a digital signal and output it.
[0006] The power converter provided in this application includes a power cabinet with a medium-high voltage area and a control cabinet with a safety voltage area, i.e., a low-voltage area. The power converter achieves communication between the power cabinet and the control cabinet through an isolation communication circuit. When achieving isolated communication, the first and second modules of the isolation communication circuit are connected by optical fiber. The first module can convert digital signals into optical signals and output them to the remote second module through optical fiber. The second module then converts the optical signals into digital signals and outputs them. The first and second modules of this scheme can be set in the safety voltage area and the medium-high voltage area, respectively. When a short circuit or device damage occurs in the medium-high voltage area, the high-voltage signal cannot be transmitted to the safety voltage area through optical fiber. At the same time, the safety voltage area and the medium-high voltage area are generally far apart, and using optical fiber connection can also avoid the influence of electromagnetic interference.
[0007] In summary, the power converter provided in this application can reduce the risk of electric shock to personnel and reduce the impact of received electromagnetic interference.
[0008] In one possible implementation, the first module includes a digital input (DI) port and an optical fiber transmitter; the DI port and the optical fiber transmitter are connected, the digital input (DI) port is used to connect to a digital signal source, and the optical fiber transmitter is used to generate an optical signal; the second module includes a digital output (DO) port and an optical fiber receiver; the optical fiber receiver and the DO port are connected, the optical fiber receiver is used to generate an electrical signal using the optical signal, the electrical signal is used to convert to a digital signal, and the DO port is used to output a digital signal.
[0009] In this implementation, the first module converts digital signals into optical signals and sends them to the second module via optical fiber. The second module then converts the optical signals back into digital signals and outputs them, thereby achieving isolated communication.
[0010] In one possible implementation, the first module further includes a first conversion circuit; the input of the first conversion circuit is connected to the DI port, and the output of the first conversion circuit is connected to the optical fiber transmitter; the first conversion circuit is used to convert the voltage of the digital signal source connected to the DI port into a first voltage and output it to the optical fiber transmitter so that the optical fiber transmitter generates an optical signal.
[0011] Since the voltage of the digital signal may differ from the operating voltage of the optical fiber transmitter during isolated communication, a first conversion circuit can be added to the first module in this implementation to perform voltage conversion.
[0012] In one possible implementation, the first conversion circuit is a step-down voltage converter.
[0013] In one possible implementation, the second module further includes a second conversion circuit; the input of the second conversion circuit is connected to the optical fiber receiver, and the output of the second conversion circuit is connected to the DO port; the second conversion circuit is used to convert the voltage of the electrical signal output by the optical fiber receiver into a second voltage and then output it to the DO port.
[0014] Since the voltage of the digital signal may differ from the operating voltage of the optical fiber receiver during isolated communication, a second conversion circuit can be added to the second module in this implementation to perform voltage conversion.
[0015] In one possible implementation, the second conversion circuit is a boost circuit.
[0016] In one possible implementation, the power converter includes a first set of isolated communication circuits and a second set of isolated communication circuits, each set of isolated communication circuits including at least one isolated communication circuit; a first module of the first set of isolated communication circuits is located in a control cabinet, and a second module of the first set of isolated communication circuits is located in a power cabinet; a first module of the second set of isolated communication circuits is located in a power cabinet, and a first module of the second set of isolated communication circuits is located in a control cabinet.
[0017] In one possible implementation, the control cabinet includes relays and circuit breakers; a second module of at least one of the first set of isolated communication circuits is connected to the relay; a first module of at least one of the second set of isolated communication circuits is connected to the relay; the relay is used to control the circuit breaker to open or close.
[0018] Secondly, this application also provides an isolated communication circuit, including: a first module and a second module; the first module and the second module are connected by an optical fiber; the first module is used to connect a digital signal source, and to convert the digital signal into an optical signal and output it to the second module through the optical fiber, wherein the digital signal source is a digital input (DI) signal source or a digital output (DO) signal source; the second module is used to convert the optical signal transmitted through the optical fiber into a digital signal and output it.
[0019] The first and second modules of this isolated communication circuit are connected via optical fiber to achieve isolated communication. The first module converts digital signals into optical signals and outputs them to the remote second module via optical fiber. The second module then converts the optical signals back into digital signals and outputs them. The first and second modules of this scheme can be set in the safe voltage zone and the medium-high voltage zone, respectively. When a short circuit or device failure occurs in the medium-high voltage zone, the high voltage signal cannot be transmitted to the safe voltage zone via optical fiber. At the same time, the safe voltage zone and the medium-high voltage zone are generally far apart, and using optical fiber connection can also avoid the influence of electromagnetic interference.
[0020] In one possible implementation, the first module includes a digital input (DI) port and an optical fiber transmitter; the DI port and the optical fiber transmitter are connected, the digital input (DI) port is used to connect to a digital signal source, and the optical fiber transmitter is used to generate an optical signal; the second module includes a digital output (DO) port and an optical fiber receiver; the optical fiber receiver and the DO port are connected, the optical fiber receiver is used to generate an electrical signal using the optical signal, the electrical signal is used to convert to a digital signal, and the DO port is used to output a digital signal.
[0021] In one possible implementation, the first module further includes a first conversion circuit; the input of the first conversion circuit is connected to the DI port, and the output of the first conversion circuit is connected to the optical fiber transmitter; the first conversion circuit is used to convert the voltage of the digital signal source connected to the DI port into a first voltage and output it to the optical fiber transmitter so that the optical fiber transmitter generates an optical signal.
[0022] In one possible implementation, the first conversion circuit is a buck converter.
[0023] In one possible implementation, the second module further includes a second conversion circuit; the input of the second conversion circuit is connected to the optical fiber receiver, and the output of the second conversion circuit is connected to the DO port; the second conversion circuit is used to convert the voltage of the electrical signal output by the optical fiber receiver into a second voltage and then output it to the DO port.
[0024] In one possible implementation, the second conversion circuit is a boost circuit. Attached Figure Description
[0025] Figure 1 A schematic diagram of the isolation scheme between the safe voltage zone and the medium- and high voltage zone;
[0026] Figure 2 A schematic diagram of an isolated communication circuit provided in an embodiment of this application;
[0027] Figure 3 Connection diagram of the isolated communication circuit provided in the embodiments of this application Figure 1 ;
[0028] Figure 4 Connection diagram of the isolated communication circuit provided in the embodiments of this application Figure 2 ;
[0029] Figure 5 A schematic diagram of another isolated communication circuit provided in an embodiment of this application;
[0030] Figure 6 A schematic diagram of yet another isolated communication circuit provided in an embodiment of this application;
[0031] Figure 7 A schematic diagram of a power converter provided in an embodiment of this application;
[0032] Figure 8 A schematic diagram of another power converter provided in an embodiment of this application;
[0033] Figure 9 This is a schematic diagram of another power converter provided in an embodiment of this application. Detailed Implementation
[0034] To enable those skilled in the art to better understand the present application, the application scenarios of the present application are described below.
[0035] See Figure 1 The figure shows a schematic diagram of the isolation scheme between the safe voltage zone and the medium- and high voltage zone.
[0036] In medium- and high-voltage systems, the safe voltage zone and the high-voltage zone where the control system is located must meet the safety regulations for reinforced insulation to prevent electric shock hazards when personnel operate the control system in the safe voltage zone. For example... Figure 1 As shown, the DI and DO signals that cross the safe voltage zone 10 and the medium-high voltage zone 20 need to be isolated; otherwise, the DI and DO signal lines may conduct dangerous voltages to the safe voltage zone 10.
[0037] The control system 11 in the safe voltage zone 10 typically uses DO signals to control high voltage from low voltage. For example, the DO signal controls an external relay 12, which in turn switches the circuit breaker 21 on or off. Finally, the coil of the circuit breaker 21 controls the opening and closing of the medium and high voltage sides. Similarly, the node signals on the medium and high voltage sides can be converted into 24V DI signals for detection by the circuit breaker 21 and relay 12. In this case, the isolation between high and low voltage currents relies solely on the insulation performance of the circuit breaker 21 itself.
[0038] However, when the circuit breaker 21 is damaged or short-circuited, the high voltage in the medium-high voltage zone 20 may be directly transmitted to the safe voltage zone 10 through the DI and DO signal loops, potentially causing electric shock to personnel. Furthermore, the entire signal link is transmitted via electrical signals, and the wiring from the safe voltage zone 10 to the medium-high voltage zone 20 is relatively long, making it susceptible to electromagnetic interference and potentially causing false signal triggering.
[0039] To address the above issues, this application provides a power converter and an isolated communication circuit. The first and second modules of the isolated communication circuit are connected via optical fiber. The first module converts the DO signal into an optical signal and outputs it through the optical fiber to a remote second module. The second module then converts the optical signal back into a DO signal and outputs it. The first and second modules are located in different voltage regions. When a short circuit or device failure occurs in the medium-high voltage region, the high-voltage signal cannot be transmitted to the safe voltage region via optical fiber. Furthermore, the safe voltage region and the medium-high voltage region are generally far apart; using optical fiber connection also avoids the influence of electromagnetic interference.
[0040] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings.
[0041] The terms "first" and "second" used in this application description are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated.
[0042] In this application, unless otherwise expressly specified and limited, the term "connection" shall be interpreted broadly. For example, "connection" may be a fixed connection, a detachable connection, or an integral part; it may be a direct connection or an indirect connection through an intermediate medium.
[0043] This application provides an isolated communication circuit, which will be described in detail below with reference to the accompanying drawings.
[0044] See Figure 2 The figure is a schematic diagram of an isolated communication circuit provided in an embodiment of this application.
[0045] The isolated communication circuit 10 provided in this application embodiment includes a first module 11 and a second module 12.
[0046] The first module 11 and the second module 12 are connected by optical fiber.
[0047] In one possible implementation, the isolated communication circuit 10 can be applied to a power converter, the power cabinet of which includes a medium-high voltage area and the control cabinet includes a safe voltage area. One of the first module 11 and the second module 12 is located in the power cabinet, and the other of the first module 11 and the second module 12 is located in the control cabinet. That is, when the first module 11 is located in the power cabinet of the power converter, the second module 12 is located in the control cabinet of the power converter, and when the second module 12 is located in the power cabinet, the first module 11 is located in the control cabinet.
[0048] The first module 11 is used to connect to a digital signal source and convert the digital signal acquired by the digital signal source into an optical signal, which is then output to the second module via optical fiber. The digital signal source can be a control system in a control cabinet or a device in a power cabinet. Specifically, when the first module 11 is located in a control cabinet, the digital signal source is a control system, and the digital signal is used to control the devices in the power cabinet; when the first module 11 is located in a power cabinet, the digital signal source is a device in the power cabinet, and the digital signal is used to indicate the operating status of the device in the power cabinet or as a detection signal for the device in the power cabinet.
[0049] The second module 12 is used to convert the optical signals transmitted through the optical fiber into digital signals and output the digital signals.
[0050] In this embodiment, the digital signal source is a digital input (DI) signal source or a digital output (DO) signal source. The DI signal source is a device in the power cabinet, and the DO signal source is a control system in the control cabinet. It should be understood that the digital signal input to the first module 11 should be consistent with the digital signal output by the second module 12, such as the same DI signal or the same DO signal, thereby achieving isolated communication functionality. In one possible implementation, the digital signal can use a first voltage to represent a "1" state and a 0 voltage to represent a "0" state; the first voltage can be, for example, 24V.
[0051] The following explanation will be based on specific application scenarios.
[0052] See also Figure 3 and Figure 4 .in, Figure 3 Connection diagram of the isolated communication circuit provided in the embodiments of this application Figure 1 ; Figure 4 Connection diagram of the isolated communication circuit provided in the embodiments of this application Figure 2 .
[0053] Figure 3 The diagram illustrates how the first module 11 of the isolated communication circuit 10 is located in the safe voltage zone 20 of the control cabinet, and the second module 12 is located in the high voltage zone 30 of the power cabinet.
[0054] Taking the isolation communication used to control the circuit breaker 32 in the medium and high voltage zone 30 to disconnect as an example, the control system 21 acts as a digital signal source to output a DO signal to the first module 11. The first module 11 converts the DO signal into an optical signal and transmits it to the second module 12 through an optical fiber. The second module 12 converts the optical signal into a DO signal and outputs it to the relay 31. The DO signal controls the relay 31 to turn the circuit breaker 21 on or off.
[0055] In this implementation, even if a short circuit or device damage occurs in the medium-high voltage zone 30, such as an insulation abnormality in the circuit breaker 32 and the relay 31, the medium-high voltage signal can at most be transmitted to the second module 12, but cannot be further transmitted to the safe voltage zone 20 through optical fiber, thus reducing the risk of electric shock to personnel in the safe voltage zone 20.
[0056] Figure 4 The diagram illustrates the implementation method where the first module 11 of the isolated communication circuit 10 is located in the medium-high voltage zone 30 of the power cabinet, and the second module 12 is located in the safe voltage zone 20 of the control cabinet.
[0057] At this time, relay 31 acts as a digital signal source, connected to the first module 11. Relay 31 is used to output DI signal to the first module 11. The first module 11 converts the DI signal into an optical signal and transmits it to the second module 12 through optical fiber. The second module 12 converts the optical signal into a DI signal and outputs it to the control system 21 in the safe voltage zone 20. At this time, the DI signal can be understood as the working status signal of relay 31 or a detection signal. The control system 21 determines the working status of relay 31 or detects relay 31 based on the DI signal.
[0058] In this implementation, even if a short circuit or device damage occurs in the medium-high voltage zone 30, such as an insulation abnormality in the circuit breaker 32 and the relay 31, the high voltage signal can at most be transmitted to the first module 11, but cannot be further transmitted to the safe voltage zone 20 through optical fiber, thus reducing the risk of electric shock to personnel in the safe voltage zone 20.
[0059] In summary, after applying the isolation communication circuit provided in this application embodiment to the power converter, the isolation between high-voltage and low-voltage circuits no longer relies solely on the insulation performance of devices in the medium- and high-voltage areas. Instead, voltage isolation is achieved through optical fiber, ensuring that when a short circuit fault or device damage occurs on the medium- and high-voltage side, the high-voltage signal cannot be transmitted to the safe voltage area via optical fiber, effectively reducing the risk of electric shock to personnel. Furthermore, even if the safe voltage area and the medium- and high-voltage area are generally far apart, the use of optical fiber connection can also avoid the influence of electromagnetic interference, ensuring the reliability of isolated communication.
[0060] The following section will explain the specific implementation method.
[0061] See Figure 5 This figure is a schematic diagram of another isolated communication circuit provided in an embodiment of this application.
[0062] Figure 5 The first module 11 of the isolated communication circuit 10 shown specifically includes a DI port 111 and an optical fiber transmitter 112. The second module 12 includes a DO port 122 and an optical fiber receiver 121.
[0063] The DI port 111 is connected to the optical fiber transmitter 112. The DI port 111 is used to connect to a digital signal source and use the digital signal provided by the digital signal source as the input signal of the first module 11.
[0064] The optical fiber transmitter 112 is used to generate an optical signal using an electrical signal.
[0065] The optical fiber receiver 121 is used to generate an electrical signal from an optical signal, and the electrical signal is used to convert it into a digital signal. The DO port 122 is used to output the digital signal.
[0066] The optical fiber transmitter 112 in this embodiment can also be referred to as the transmitting part of an optical transceiver, and the optical fiber receiver 121 can also be referred to as the receiving part of an optical transceiver.
[0067] In practical applications, since the voltage of the digital signal may differ from the operating voltage of the fiber optic transmitter / receiver during isolated communication, a conversion circuit can be added to the first module 11 and the second module 12 to perform the conversion, which will be explained in detail below.
[0068] See Figure 6 This figure is a schematic diagram of another isolated communication circuit provided in an embodiment of this application.
[0069] In this embodiment of the application, the first module 11 of the isolated communication circuit 10 further includes a first conversion circuit 113, and the second module 12 further includes a second conversion circuit 123.
[0070] The input of the first conversion circuit 113 is connected to the DI port 111, and the output is connected to the optical fiber transmitter 112. The first conversion circuit 113 is used to convert the voltage of the digital signal connected to the DI port 111 into a first voltage and output it to the optical fiber transmitter so that the optical fiber transmitter generates an optical signal.
[0071] The first voltage is specifically related to the voltage of the optical fiber transmitter 112 when it is working. This application embodiment does not make a specific limitation on this. For example, the first voltage can be 3.3V or 5V.
[0072] The voltage when the digital signal is in state "1" is the second voltage. This application embodiment does not specifically limit the magnitude of the second voltage. Taking the second voltage as 24V and the first voltage as 3.3V or 5V as an example, the first conversion circuit 113 is a buck circuit, which is used to convert the second voltage into a lower first voltage.
[0073] The input of the second conversion circuit 123 is connected to the optical fiber receiver 121, and the output of the second conversion circuit 123 is connected to the DO port.
[0074] The second conversion circuit 123 is used to convert the voltage of the electrical signal output 121 from the optical fiber receiver into a second voltage and then output it to the DO port 122.
[0075] Similarly, taking a second voltage of 24V and a first voltage of 3.3V or 5V as an example, the second conversion circuit 123 is a boost circuit, used to convert the first voltage into a higher second voltage before output.
[0076] In summary, the isolation communication circuit provided in this application not only reduces the risk of electric shock to personnel and the impact of received electromagnetic interference, but also ensures the normal operation of the optical fiber transmitter 112 through the first conversion circuit and ensures that the voltage of the digital signal output by the second module is equal to the voltage of the digital signal input to the first module through the second conversion circuit 123, thereby ensuring the reliability of the isolation communication function.
[0077] Based on the isolated communication circuits provided in the above embodiments, this application also provides a power converter, which may include one or more isolated communication circuits provided in the embodiments. The following is a detailed description in conjunction with the accompanying drawings.
[0078] See Figure 7 This figure is a schematic diagram of a power converter provided in an embodiment of this application.
[0079] The power converter provided in this application embodiment may include a power cabinet and a control cabinet. The power cabinet and the control cabinet may be physically separated.
[0080] The control cabinet includes a safety voltage zone 20, which may include a control system 21.
[0081] The control system 21 can be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), a digital signal processor (DSP), or a combination thereof. The PLD can be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof; this application does not specifically limit the specific type of PLD.
[0082] The power cabinet may include a medium-high voltage zone 20. For ease of explanation, this embodiment uses a medium-high voltage zone 20 specifically including devices such as relays 31 and circuit breakers 32 as an example. It should be understood that in actual applications, the medium-high voltage zone 20 may also include other controlled devices, such as cooling systems (e.g., fans).
[0083] Relay 31 is used to control the circuit breaker 32 to open or close. In one possible implementation, circuit breaker 32 can be located on the DC side or AC side of the power conversion circuit in the power cabinet; this application embodiment does not impose specific limitations. For example, when the power conversion circuit is an inverter circuit, circuit breaker 32 can be located on the DC side of the inverter circuit.
[0084] One of the first module 11 and the second module 12 is located in the power cabinet, and the other of the first module 11 and the second module 12 is located in the control cabinet. Figure 7 In the implementation shown, the second module 12 of the isolation communication circuit is located in the power cabinet, i.e., in the medium-high voltage zone 30; the first module 11 of the isolation communication circuit is located in the control cabinet, i.e., in the safe voltage zone.
[0085] At this time, the control system 21 acts as a DO signal source to output a DO signal to the first module 11. The first module 11 converts the DO signal into an optical signal and transmits it to the second module 12 through an optical fiber. The second module 12 converts the optical signal into a DO signal and outputs it to the relay 31. The DO signal controls the relay 31 to turn the circuit breaker 21 on or off.
[0086] See Figure 8 This figure is a schematic diagram of another power converter provided in an embodiment of this application.
[0087] The first module 11 of the isolation communication circuit is located in the power cabinet of the power converter, i.e., in the medium-high voltage zone 30. The second module 12 of the isolation communication circuit is located in the control cabinet of the power converter, i.e., in the safe voltage zone 20.
[0088] At this time, relay 31 is connected to the first module 11. Relay 31 acts as a DI signal source and is used to output DI signal to the first module 11. The first module 11 converts the DI signal into an optical signal and transmits it to the second module 12 through optical fiber. The second module 12 converts the optical signal into a DI signal and outputs it to the control system 21 in the safe voltage zone 20. At this time, the DI signal can be understood as the working status signal of relay 31 or a detection signal. The control system 21 determines the working status of relay 31 or detects relay 31 based on the DI signal.
[0089] The above Figure 7 and Figure 8In this paper, we will only take the example of a power converter that includes one isolated communication circuit. The following describes the implementation method when the power converter includes multiple isolated communication circuits.
[0090] See Figure 9 This figure is a schematic diagram of another power converter provided in an embodiment of this application.
[0091] In this embodiment, the power converter may include a first set of isolated communication circuits and a second set of isolated communication circuits.
[0092] The first module of the first set of isolated communication circuits is located in the control cabinet of the power converter (i.e., in the safe voltage zone 20), and the second module of the first set of isolated communication circuits is located in the power cabinet of the power converter (i.e., in the medium and high voltage zone 30).
[0093] The first module of the second set of isolated communication circuits is located in the power cabinet of the power converter (i.e., in the medium-high voltage zone 30), and the second module of the second set of isolated communication circuits is located in the control cabinet of the power converter (i.e., in the safe voltage zone 20).
[0094] It should be understood that the power converter may include only the first set of isolation communication circuits or only the second set of isolation communication circuits, which will not be described in detail in the embodiments of this application.
[0095] When the power converter includes both a first group of isolated communication circuits and a second group of isolated communication circuits, each group of isolated communication circuits may include at least one isolated communication circuit. Figure 9 The following description uses the example of the first group of isolated communication circuits including isolated communication circuit 10A and the second group of isolated communication circuits including isolated communication circuit 10B, but this does not constitute a limitation on the technical solution of this application. For example, each group of isolated communication circuits may include two or more isolated communication circuits.
[0096] At this time, the control system 21 can output a DO signal, which is transmitted to the relay 31 through the isolation communication circuit 10A, and then the relay 31 is controlled to turn on or off the circuit breaker 21. The DI signal, which is used to characterize the working state signal or detection signal of the relay 31, can be transmitted to the control system 21 through the isolation communication circuit 10B, so that the control system 21 can determine the working state of the relay 31 or detect the relay 31 based on the DI signal.
[0097] In summary, the isolation communication circuit in the power converter provided in this application achieves voltage isolation through optical fiber, ensuring that when a short circuit fault or device damage occurs on the high-voltage side, the high-voltage signal cannot be transmitted to the safe voltage area through the optical fiber, effectively reducing the risk of electric shock to personnel. Furthermore, even if the safe voltage area and the high-voltage area are generally far apart, the use of optical fiber connection can also avoid the influence of electromagnetic interference, ensuring the reliability of the isolated communication.
[0098] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.
[0099] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on its differences from other embodiments. The device embodiments described above are merely illustrative, and the units and modules described as separate components may or may not be physically separate. Furthermore, some or all of the units and modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.
[0100] The above description is only a specific embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.
Claims
1. A power converter, characterized by, include: Power cabinet, control cabinet, isolated communication circuit; The isolated communication circuit includes a first module and a second module connected by optical fiber. One of the first module and the second module is located in the power cabinet, and the other of the first module and the second module is located in the control cabinet; The first module is used to connect to a digital signal source and to convert the digital signal into an optical signal and transmit it to the second module through the optical fiber. The digital signal source is a digital input (DI) signal source or a digital output (DO) signal source. The DO signal source is the control system in the control cabinet, and the DI signal source is the device in the power cabinet. The second module is used to convert the optical signal transmitted by the optical fiber into the digital signal and output it.
2. The power converter of claim 1, wherein, The first module includes a digital input (DI) port and an optical fiber transmitter. The DI port is connected to the optical fiber transmitter, the digital input DI port is used to connect to the digital signal source, and the optical fiber transmitter is used to generate the optical signal; The second module includes a digital output (DO) port and an optical fiber receiver. The optical fiber receiver is connected to the DO port. The optical fiber receiver is used to generate an electrical signal using an optical signal. The electrical signal is used to convert the signal into a digital signal. The DO port is used to output the digital signal.
3. The power converter of claim 2, wherein, The first module also includes a first conversion circuit; The input terminal of the first conversion circuit is connected to the DI port, and the output terminal of the first conversion circuit is connected to the optical fiber transmitter. The first conversion circuit is used to convert the voltage of the digital signal source connected to the DI port into a first voltage and output it to the optical fiber transmitter so that the optical fiber transmitter generates the optical signal.
4. The power converter of claim 3, wherein, The second module also includes a second conversion circuit; The input of the second conversion circuit is connected to the optical fiber receiver, and the output of the second conversion circuit is connected to the DO port. The second conversion circuit is used to convert the voltage of the electrical signal output from the optical fiber receiver into a second voltage and then output it to the DO port.
5. The power converter of claim 4, wherein, The first conversion circuit is a buck converter, and the second conversion circuit is a boost converter.
6. The power converter of claim 1, wherein, The power converter includes a first group of isolated communication circuits and a second group of isolated communication circuits, each group of isolated communication circuits including at least one isolated communication circuit. The first module of the first group of isolated communication circuits is located in the control cabinet, and the second module of the first group of isolated communication circuits is located in the power cabinet. The first module of the second set of isolated communication circuits is located in the power cabinet, and the first module of the second set of isolated communication circuits is located in the control cabinet.
7. The power converter of claim 6, wherein, The control cabinet includes relays and circuit breakers; The second module of at least one of the first group of isolated communication circuits is connected to the relay; At least one of the isolated communication circuits in the second group of isolated communication circuits is connected to the relay in its first module. The relay is used to control the circuit breaker to open or close.
8. An isolated communication circuit, comprising: include: Module 1 and Module 2; The first module and the second module are connected via optical fiber; the first module is used to connect to a digital signal source, and to convert the digital signal into an optical signal and output it to the second module via the optical fiber. The digital signal source is a digital input (DI) signal source or a digital output (DO) signal source. The second module is used to convert the optical signal transmitted by the optical fiber into the digital signal and output it.
9. The isolated communication circuit of claim 8, wherein, The first module includes a digital input (DI) port and an optical fiber transmitter. The DI port is connected to the optical fiber transmitter, the digital input DI port is used to connect to the digital signal source, and the optical fiber transmitter is used to generate the optical signal; The second module includes a digital output (DO) port and an optical fiber receiver. The optical fiber receiver is connected to the DO port. The optical fiber receiver is used to generate an electrical signal using an optical signal. The electrical signal is used to convert the signal into a digital signal. The DO port is used to output the digital signal.
10. The isolated communication circuit of claim 9, wherein, The first module also includes a first conversion circuit; The input terminal of the first conversion circuit is connected to the DI port, and the output terminal of the first conversion circuit is connected to the optical fiber transmitter. The first conversion circuit is used to convert the voltage of the digital signal source connected to the DI port into a first voltage and output it to the optical fiber transmitter so that the optical fiber transmitter generates the optical signal.
11. The isolated communication circuit of claim 9 or 10, wherein, The second module also includes a second conversion circuit; The input of the second conversion circuit is connected to the optical fiber receiver, and the output of the second conversion circuit is connected to the DO port. The second conversion circuit is used to convert the voltage of the electrical signal output from the optical fiber receiver into a second voltage and then output it to the DO port.