A redundant communication interface circuit for an energy harvesting device

Abstract

This utility model discloses a redundant communication interface circuit for an energy acquisition device, relating to the field of energy metering and data communication technology. It includes a main communication interface, a backup communication interface, a signal coupler, a status detection unit, and a switching actuator. The signal coupler connects the data receiving pins of the two interfaces to transmit status signals. The status detection unit triggers the switching actuator based on these signals, which synchronously switches the data bus to the backup channel via an electromagnetic relay group and a mechanical linkage arm. This application enables automatic and seamless switching when the main and backup communication links malfunction.

Description

Technical Field

[0001] This utility model relates to the field of power metering and data communication technology, and in particular to a redundant communication interface circuit for a power acquisition device. Background Technology

[0002] Power acquisition equipment is used to obtain power parameters from the power system and upload the data to a monitoring or management system via a communication interface. It has significant application value in smart grids, energy management, and remote monitoring. These devices are typically equipped with communication interface circuits to support data interaction with host computers or other terminals. Common communication methods include RS-485, CAN, Ethernet, or wireless communication. To improve system reliability, some devices employ redundancy, configuring multiple communication channels to switch to a backup channel in case of a primary channel failure, thus ensuring communication continuity.

[0003] However, when existing power acquisition equipment achieves communication redundancy, its redundant communication interface circuits often use independent physical channels and control logic. There is a lack of effective state coordination and automatic switching mechanisms between channels. When the main communication link is abnormal, the switching process may be delayed or require external intervention, which will affect the continuity and real-time performance of data transmission and make it difficult to meet the requirements of seamless communication switching in high-reliability application scenarios. Utility Model Content

[0004] This invention provides a redundant communication interface circuit for an energy acquisition device. Addressing the problem of the lack of state coordination and automatic switching mechanisms between redundant communication channels in the prior art, it achieves rapid and seamless switching of the primary and backup communication links under abnormal conditions by setting up shared detection nodes and linkage switching structures at the physical layer and signal path layer, thereby maintaining the continuity and real-time performance of data transmission.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] Design a redundant communication interface circuit for a power acquisition device, including a main communication interface, a backup communication interface, a signal coupler, a status detection unit, and a switching actuator, wherein:

[0007] The main communication interface and the backup communication interface are respectively configured in the communication port area of ​​the power acquisition device, and each is connected to an independent physical communication line for accessing different external communication networks; the signal coupler is set between the input terminals of the main communication interface and the backup communication interface, and contains a pair of differential signal coupling coils. One end of the differential signal coupling coil is connected to the data receiving pin of the main communication interface, and the other end is connected to the data receiving pin of the backup communication interface, for transmitting communication status signals between the two communication interfaces;

[0008] The status detection unit is integrated on the output side of the signal coupler. It contains a voltage comparator and a reference level source. The positive input terminal of the voltage comparator is connected to the center tap of the differential signal coupling coil, and the negative input terminal is connected to the reference level source. When the data receiving pin of the main communication interface experiences a signal interruption or level abnormality, the potential of the center tap of the differential signal coupling coil shifts, and the voltage comparator outputs a high-level trigger signal.

[0009] The switching actuator includes an electromagnetic relay group and a mechanical linkage arm. The electromagnetic relay group consists of two normally open relays, which are connected in series in the data transmission paths of the main communication interface and the backup communication interface, respectively. One end of the mechanical linkage arm is fixedly connected to the armature of the electromagnetic relay group, and the other end is connected to the toggle lever of the data bus selection switch. When the status detection unit outputs a high-level trigger signal, the main communication relay in the electromagnetic relay group is opened and the backup communication relay is closed. At the same time, the mechanical linkage arm drives the data bus selection switch to switch to the data channel of the backup communication interface.

[0010] Optionally, the signal coupler further includes a shielding shell and a magnetic core support. The shielding shell encloses the differential signal coupling coil to suppress external electromagnetic interference. The magnetic core support is made of a high permeability material and is fixedly installed inside the shielding shell to support the differential signal coupling coil and enhance magnetic coupling efficiency.

[0011] Optionally, the state detection unit further includes a filter capacitor and a hysteresis resistor network. The filter capacitor is connected in parallel to the input terminal of the voltage comparator to filter out high-frequency noise. The hysteresis resistor network is connected between the output terminal and the positive input terminal of the voltage comparator to set the hysteresis threshold for level switching and prevent false triggering due to transient interference.

[0012] Optionally, the switching actuator further includes a reset spring and a limit block. One end of the reset spring is connected to the mechanical linkage arm, and the other end is fixed to the equipment housing. It is used to reset the data bus selection switch to the main communication channel after the main communication interface returns to normal. The limit block is set at both ends of the movement trajectory of the mechanical linkage arm to limit its maximum swing angle and avoid excessive impact.

[0013] Optionally, the power supply pins of the main communication interface and the backup communication interface are respectively connected to a voltage regulation and isolation circuit. The voltage regulation and isolation circuit includes a linear regulator and an optocoupler, which are used to provide a stable operating voltage after isolation for the communication interface and to block ground loop interference.

[0014] Optionally, the data bus selection switch includes multiple sets of synchronous contacts and a rotating shaft. The multiple sets of synchronous contacts correspond to data transmission, data reception and handshake signal lines respectively. The rotating shaft passes through the center of all synchronous contacts and is fixedly connected to the mechanical linkage arm to ensure that each signal line switches synchronously.

[0015] Optionally, the communication port area of ​​the power acquisition device is also provided with a status indicator group, which includes a main communication status light and a backup communication status light, which are respectively connected to the carrier detection pins of the main communication interface and the backup communication interface through current limiting resistors, for real-time display of the currently active communication channel;

[0016] Optionally, the output of the status detection unit is also connected to a non-volatile memory, which is used to record the timestamp and triggering reason of each communication switch, so as to facilitate subsequent fault analysis and system maintenance.

[0017] Optionally, the coil drive terminal of the electromagnetic relay group is connected to a transient suppression diode to absorb the back electromotive force generated when the relay is disconnected, thus protecting the output stage circuit of the status detection unit.

[0018] The beneficial effects of this utility model are:

[0019] This redundant communication interface circuit establishes a state-aware path between the primary and backup communication interfaces via a signal coupler. It utilizes a differential signal coupling coil to monitor the signal integrity of the primary communication link in real time. If the primary link experiences an interruption or anomaly, the state detection unit immediately generates a switching command, driving the switching actuator to complete a hard switch of the physical channel. The entire process does not rely on external control logic or software intervention; the switching response time is limited only by the operating speed of the electromagnetic relay and the inertia of the mechanical linkage arm, typically completed within milliseconds. Because the switching actuator uses a mechanical linkage structure to synchronously control the data bus selection switch and relay group, it ensures synchronous switching of data transmission, reception, and control signals, avoiding data misalignment or protocol conflicts. Furthermore, the voltage regulation isolation circuit and shielded enclosure effectively enhance the anti-interference capability of the communication interface, while the introduction of non-volatile memory provides reliable event traceability for system maintenance. This circuit has a simple structure and high reliability, making it suitable for smart grids and industrial automation scenarios with stringent requirements for communication continuity. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the redundant communication interface circuit of an energy acquisition device according to the present invention;

[0021] Explanation of reference numerals in the attached figures:

[0022] 1. Main communication interface; 2. Backup communication interface; 3. Signal coupler; 4. Status detection unit; 5. Switching actuator; 6. Differential signal coupling coil; 7. Electromagnetic relay group; 8. Mechanical linkage arm; 9. Data bus selection switch; 10. Voltage regulation and isolation circuit. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0024] like Figure 1 As shown: This utility model provides a redundant communication interface circuit for a power acquisition device. This circuit is located in the communication port area of ​​the power acquisition device and is used to realize status sensing and physical channel switching between the primary and backup communication links. The redundant communication interface circuit includes a primary communication interface 1, a backup communication interface 2, a signal coupler 3, a status detection unit 4, and a switching execution mechanism 5.

[0025] The main communication interface 1 and the backup communication interface 2 are respectively configured in adjacent positions in the communication port area of ​​the power acquisition equipment. Each is connected to an independent physical communication line for accessing different external communication networks. Both the main communication interface 1 and the backup communication interface 2 adopt the standard RS485 or CAN bus physical interface form, and their pin definitions include data transmission pins, data reception pins, power supply pins, and ground pins.

[0026] Signal coupler 3 is positioned between the data receiving pins of the main communication interface 1 and the backup communication interface 2, and internally contains a differential signal coupling coil 6. One end of the differential signal coupling coil 6 is connected to the data receiving pin of the main communication interface 1, and the other end is connected to the data receiving pin of the backup communication interface 2. The center tap of the differential signal coupling coil 6 is led out to the status detection unit 4. The differential signal coupling coil 6 is wound on a magnetic core support made of a high-permeability material. The magnetic core support is fixedly installed inside a shielded shell, which is made of conductive metal material and grounded to suppress the influence of external electromagnetic interference on the differential signal coupling coil 6.

[0027] The status detection unit 4 is integrated on the output side of the signal coupler 3, and it contains a voltage comparator and a reference level source. The positive input of the voltage comparator is connected to the center tap of the differential signal coupling coil 6, and the negative input is connected to the reference level source. When the data receiving pin of the main communication interface 1 is in normal communication mode, there is a stable differential signal across the differential signal coupling coil 6, and the center tap potential is maintained near the reference level. When the data receiving pin of the main communication interface 1 experiences signal interruption, short circuit, or abnormal level, the magnetic flux balance of the differential signal coupling coil 6 is disrupted, the center tap potential shifts, exceeding the reference level set threshold, and the voltage comparator outputs a high-level trigger signal.

[0028] The status detection unit 4 also includes a filter capacitor and a hysteresis resistor network. The filter capacitor is connected in parallel between the positive input terminal of the voltage comparator and ground to filter out high-frequency noise interference and prevent false judgments caused by transient interference. The hysteresis resistor network is connected between the output terminal and the positive input terminal of the voltage comparator to form a positive feedback loop, setting the hysteresis threshold for level switching, and ensuring that the switching action is triggered only after the main communication interface 1 has been continuously abnormal for more than a set time.

[0029] The switching actuator 5 includes an electromagnetic relay group 7, a mechanical linkage arm 8, and a data bus selection switch 9. The electromagnetic relay group 7 consists of two normally open electromagnetic relays, one connected in series in the data transmission path of the main communication interface 1, and the other connected in series in the data transmission path of the backup communication interface 2. The coil drive terminal of the electromagnetic relay group 7 is connected to the output terminal of the status detection unit 4, and a transient suppression diode is connected in parallel across the coil to absorb the back electromotive force generated when the relay is disconnected, protecting the output stage circuit of the status detection unit 4.

[0030] One end of the mechanical linkage arm 8 is fixedly connected to the armature of the electromagnetic relay group 7, and the other end is connected to the toggle lever of the data bus selection switch 9. When the status detection unit 4 outputs a high-level trigger signal, the coil of the main communication relay in the electromagnetic relay group 7 is de-energized and its contacts open, while the coil of the backup communication relay is energized and its contacts close. The movement of the armature causes the mechanical linkage arm 8 to swing, and the mechanical linkage arm 8 pushes the toggle lever of the data bus selection switch 9, causing the data bus selection switch 9 to switch to the data channel of the backup communication interface 2.

[0031] The data bus selection switch 9 includes multiple sets of synchronous contacts and a rotating shaft. The synchronous contacts correspond to the data transmission line, data reception line, and handshake signal line, respectively. The rotating shaft passes through the center of all synchronous contacts and is fixedly connected to the mechanical linkage arm 8. The swinging of the mechanical linkage arm 8 drives the rotating shaft to rotate, causing all synchronous contacts to switch synchronously. This ensures that data transmission, reception, and control signals are transferred synchronously between the primary and backup channels, avoiding protocol conflicts or data misalignment caused by signal asynchrony.

[0032] The switching actuator 5 also includes a reset spring and limit blocks. One end of the reset spring is connected to the mechanical linkage arm 8, and the other end is fixed to the equipment housing. When the main communication interface 1 returns to normal communication status, the status detection unit 4 stops outputting a high-level trigger signal, the coil of the electromagnetic relay group 7 is de-energized, the reset spring pulls the mechanical linkage arm 8 back to its original position, and drives the data bus selection switch 9 to switch back to the data channel of the main communication interface 1. The limit blocks are set at both ends of the movement trajectory of the mechanical linkage arm 8 to limit its maximum swing angle and prevent the mechanical linkage arm 8 from damaging the data bus selection switch 9 or the electromagnetic relay group 7 due to inertial impact.

[0033] The power supply pins of the main communication interface 1 and the backup communication interface 2 are respectively connected to the voltage regulation and isolation circuit 10. The voltage regulation and isolation circuit 10 includes a linear regulator and an optocoupler. The linear regulator converts the main power supply of the device into the operating voltage required by the communication interface. The optocoupler is placed between the power input terminal and the output terminal to achieve electrical isolation, block ground loop interference, and improve the common-mode interference immunity of the communication interface.

[0034] The communication port area of ​​the power acquisition equipment is also equipped with a status indicator group, which includes a main communication status light and a backup communication status light. The main communication status light is connected to the carrier detection pin of the main communication interface 1 through a current-limiting resistor, and the backup communication status light is connected to the carrier detection pin of the backup communication interface 2 through a current-limiting resistor. When the main communication interface 1 is active, the main communication status light is lit; when the switching actuator 5 switches to the backup communication interface 2, the backup communication status light is lit, displaying the currently active communication channel in real time.

[0035] The output of the status detection unit 4 is also connected to a non-volatile memory. Each time the status detection unit 4 outputs a high-level trigger signal, the non-volatile memory records the current system timestamp and trigger reason code. The trigger reason code is encoded according to the duration and amplitude of the voltage comparator output signal, which facilitates subsequent fault analysis and allows system maintenance personnel to trace communication switching events.

[0036] In this embodiment, the main communication interface 1 and the backup communication interface 2 use the same physical interface specifications, ensuring that no external wiring adjustments are required during switching. The turns ratio of the differential signal coupling coil 6 is 1:1, ensuring the symmetry of signal levels between the main and backup communication interfaces. The voltage comparator uses a low-power, high-response-speed model, ensuring that status judgment is completed within milliseconds. The operating time of the electromagnetic relay group 7 does not exceed five milliseconds, and combined with the rigid connection structure of the mechanical linkage arm 8, the entire switching process is completed within ten milliseconds, meeting the stringent requirements of power acquisition equipment for communication continuity.

[0037] The shielding shell of signal coupler 3 is fixed to the internal metal bracket of the equipment with screws to achieve good grounding. The magnetic core bracket is made of permalloy, which has high initial permeability and low coercivity, improving the differential signal coupling efficiency. The linear regulator in the voltage regulation and isolation circuit 10 has an output voltage accuracy of ±2% and a ripple voltage of less than 50 millivolts, ensuring stable operating voltage of the communication interface.

[0038] The synchronous contacts of the data bus selection switch 9 are gold-plated, with a contact resistance of less than ten milliohms and a durability of no less than one hundred thousand cycles. The mechanical linkage arm 8 is made of stainless steel by stamping, possessing high strength and fatigue resistance. The return spring is made of phosphor bronze, and its elastic coefficient has been precisely calculated to ensure reliable reset after the electromagnetic relay group 7 is de-energized.

[0039] The non-volatile memory uses a serial EEPROM chip, which is connected to the status detection unit 4 via an I2C bus. It has a storage capacity of 64 kilobytes and can record at least 1,000 communication switching events. The status indicator lights use high-brightness LEDs with an operating current not exceeding 5 mA, limited by surface-mount resistors, and are mounted in a visible position on the front panel of the device.

[0040] When the power acquisition device is powered on and initialized, the redundant communication interface circuit of this invention defaults to enabling the main communication interface 1. During normal operation of the main communication interface 1, a stable differential signal exists at both ends of the differential signal coupling coil 6, the center tap potential is stable, the voltage comparator outputs a low level, the main communication relay in the electromagnetic relay group 7 remains closed, the backup communication relay remains open, and the data bus selection switch 9 connects to the data channel of the main communication interface 1. When the main communication interface 1 experiences abnormal data receiving pin levels due to line disconnection, short circuit, or external interference, the magnetic flux balance of the differential signal coupling coil 6 is disrupted, the center tap potential shifts, the voltage comparator outputs a high level, driving the electromagnetic relay group 7 to operate. Simultaneously, the mechanical linkage arm 8 drives the data bus selection switch 9 to switch to the backup communication interface 2, achieving seamless switching of the communication link. After the main communication interface 1 returns to normal, the status detection unit 4 stops outputting a high level, the reset spring pulls the mechanical linkage arm 8 back to its original position, and the system automatically switches back to the main communication interface 1. The entire switching process does not rely on external controllers or software logic; it is entirely completed autonomously by the hardware circuit, ensuring the continuity and real-time performance of data transmission even under extreme operating conditions.

[0041] The technical solution of this utility model is not limited to the specific embodiments described above. All technical modifications made according to the technical solution of this utility model fall within the protection scope of this utility model.

Claims

1. A redundant communication interface circuit for an electric energy harvesting device, characterized by: It includes a main communication interface (1), a backup communication interface (2), a signal coupler (3), a status detection unit (4), and a switching actuator (5), wherein: The main communication interface (1) and the backup communication interface (2) are respectively connected to independent physical communication lines; The signal coupler (3) is located between the data receiving pins of the main communication interface (1) and the backup communication interface (2). It contains a differential signal coupling coil (6). One end of the differential signal coupling coil (6) is connected to the data receiving pin of the main communication interface (1), and the other end is connected to the data receiving pin of the backup communication interface (2). The center tap is connected to the status detection unit (4). The state detection unit (4) includes a voltage comparator and a reference level source. The positive input terminal of the voltage comparator is connected to the center tap of the differential signal coupling coil (6), and the negative input terminal is connected to the reference level source. The switching actuator (5) includes an electromagnetic relay group (7), a mechanical linkage arm (8), and a data bus selection switch (9). The electromagnetic relay group (7) consists of two normally open relays, which are connected in series on the data transmission paths of the main communication interface (1) and the backup communication interface (2), respectively. One end of the mechanical linkage arm (8) is connected to the armature of the electromagnetic relay group (7), and the other end is connected to the toggle lever of the data bus selection switch (9).

2. The redundant communication interface circuit for an electric energy harvesting device of claim 1, wherein: The signal coupler (3) also includes a shielding shell and a magnetic core support. The shielding shell encloses the differential signal coupling coil (6), and the magnetic core support is made of a high permeability material and fixed inside the shielding shell.

3. The redundant communication interface circuit for an electric energy-harvesting device of claim 1, wherein: The state detection unit (4) also includes a filter capacitor and a hysteresis resistor network. The filter capacitor is connected in parallel between the positive input terminal of the voltage comparator and ground, and the hysteresis resistor network is connected between the output terminal and the positive input terminal of the voltage comparator.

4. The redundant communication interface circuit for an electric energy-harvesting device of claim 1, wherein: The switching actuator (5) also includes a reset spring and a limit block. One end of the reset spring is connected to the mechanical linkage arm (8), and the other end is fixed to the equipment housing. The limit block is set at both ends of the movement trajectory of the mechanical linkage arm (8).

5. The redundant communication interface circuit for an electric energy-harvesting device of claim 1, wherein: The power supply pins of the main communication interface (1) and the backup communication interface (2) are respectively connected to the voltage regulation isolation circuit (10), which includes a linear regulator and an optocoupler.

6. The redundant communication interface circuit for an electric energy-harvesting device of claim 1, wherein: The data bus selection switch (9) includes multiple sets of synchronous contacts and a rotating shaft. The multiple sets of synchronous contacts correspond to the data transmission line, data reception line and handshake signal line respectively. The rotating shaft passes through the center of all synchronous contacts and is fixedly connected to the mechanical linkage arm (8).

7. The redundant communication interface circuit for an electric energy-harvesting device of claim 1, wherein: The communication port area of ​​the power acquisition device is provided with a status indicator group, which includes a main communication status light and a backup communication status light. The main communication status light is connected to the carrier detection pin of the main communication interface (1) through a current limiting resistor, and the backup communication status light is connected to the carrier detection pin of the backup communication interface (2) through a current limiting resistor.

8. The redundant communication interface circuit for an electric energy-harvesting device of claim 1, wherein: The output of the state detection unit (4) is connected to a non-volatile memory to record the timestamp and trigger reason for communication switching.

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