CN113904315A - Method for protecting serial port of data communication gateway machine of transformer substation - Google Patents
Method for protecting serial port of data communication gateway machine of transformer substation Download PDFInfo
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- CN113904315A CN113904315A CN202111218968.8A CN202111218968A CN113904315A CN 113904315 A CN113904315 A CN 113904315A CN 202111218968 A CN202111218968 A CN 202111218968A CN 113904315 A CN113904315 A CN 113904315A
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- data communication
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
- H02H9/041—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage using a short-circuiting device
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
- H02H9/042—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage comprising means to limit the absorbed power or indicate damaged over-voltage protection device
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
- H02H9/06—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage using spark-gap arresters
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Abstract
The invention discloses a substation data communication gateway machine serial port protection method, which relates to the technical field of substation data communication, and is designed aiming at a substation data communication gateway machine serial port protection circuit, wherein a protection circuit is added in an RS-232 serial port TTL and RS-232 serial port transceiving level conversion circuit, and a four-stage protection circuit is adopted to protect an external serial port signal input by an external serial port connector, so that a serial port signal loop resists external interference: the first stage adopts a gas discharge tube and a fixed resistor to absorb surge impact interference; the second stage adopts a transient suppression diode to absorb residual surge impact interference and static interference; the third stage is an RC low-pass filter circuit for further filtering the front-end residual pulse interference; the fourth stage is an isolation chip which is used for isolating and protecting a rear-stage core circuit. The invention can improve the anti-interference capability of the serial port signal loop of the substation data communication gateway machine.
Description
Technical Field
The invention relates to the technical field of transformer substation data communication, in particular to a method for protecting a serial port of a transformer substation data communication gateway machine.
Background
Because the serial communication has low cost, simple wiring and mature and stable technology, the serial communication is used and started early in an information acquisition system of a transformer substation, and is widely used in various transformer substations with large and small sizes at present, but because the serial communication mode is weak in anti-interference capability compared with network communication, particularly when surge tests and fast transient pulse group interference tests are carried out, because the interference protection of a conventional serial signal loop on large energy and high voltage is not particularly perfect, the transient overvoltage impact is caused on core devices such as a serial level conversion circuit and even a CPU (central processing unit), a serial chip and the like at a high probability, and the irrecoverable damage is caused.
Disclosure of Invention
The technical task of the invention is to provide a method for protecting the serial port of the data communication gateway machine of the transformer substation, aiming at the defects, and the anti-interference capability of the serial port signal loop of the data communication gateway machine of the transformer substation can be improved.
The technical scheme adopted by the invention for solving the technical problems is as follows:
a kind of substation data communication network shutdown serial port protection method, this method is designed to the substation data communication network shutdown serial port protection circuit, increase the protection circuit in RS-232 serial port TTL and RS-232 serial port receiving and dispatching level switching circuit, adopt the four-stage protection circuit, protect the external serial port signal input by the external serial port connector, make the serial port signal loop resist the external disturbance:
the first stage adopts a Gas Discharge Tube (GDT) and a fixed resistor to absorb surge impact interference;
the second stage adopts a transient suppression diode (TVS) to absorb residual surge impact interference and static interference;
the third stage is an RC low-pass filter circuit, so that the front-end residual pulse interference is further filtered, and the interference of serial port signals of the RS-232 transceiver is reduced;
the fourth stage is an isolation chip which is used for isolating and protecting a rear-stage core circuit.
The method can improve the anti-interference capability of the serial port signal loop of the data communication gateway machine of the transformer substation, and the data communication gateway machine product can meet the requirement of electromagnetic compatibility test indexes in GB/T17628 by performing multi-stage protection on the serial port signal input by the serial port connector.
Preferably, the first-stage protection circuit comprises 1 tripolar gas discharge tube and 2 fixed resistors;
the outside is coupled to the large-energy surge impact absorption consumption between the line and between the line and the ground through the RS-232 connector, most surge impact is quickly discharged to the ground through the shell, and residual impact is processed by a rear-stage protection circuit.
In view of the characteristics of large flow, high conduction voltage, slow reaction time and continuous flow of the gas discharge tube, the first-stage protection circuit has good surge impact interference protection performance and poorer pulse interference and electrostatic interference protection capabilities.
Preferably, pins 1 and 3 of the three-pole gas discharge tube are respectively connected with TXD and RXD, and pin 2 is a common pin and is connected with the ground through the machine shell;
the three-pole gas discharge tube selects 3RL090M-5-S, 3RL090M-5-S direct current breakdown voltage 90V and pulse breakdown voltage 600V, and the common pin is grounded, so that surge impact coupled to TXD and RXD signal lines can be effectively discharged.
Furthermore, the second-stage protection circuit is 2 transient suppression diodes (TVS), absorbs residual surge interference, pulse interference and electrostatic interference of the first-stage protection circuit, and quickly discharges the residual surge interference, pulse interference and electrostatic interference to the ground through the casing.
In view of the characteristics of high response speed, high reliability, low on-state voltage, small flow and the like of the TVS tube, the second-stage protection circuit can effectively absorb transient pulse interference and electrostatic interference, so that the interference energy in the rear-stage protection circuit is reduced to be within the bearable range of the device.
Preferably, the transient suppression diode is SMAJ15CA, and residual interference of TXD and RXD signal lines is continuously and quickly released to the ground through the shell; SMAJ15CA cuts off voltage 15V reversely, and limits the voltage between TXD and RXD signal lines and the chassis ground to be below 15V, thereby reducing surge, transient and electrostatic interference residual energy flowing into a rear-stage protection circuit.
Furthermore, the third-level protection circuit realizes an RC low-pass filter circuit by matching 2 groups of 33 ohm fixed resistors with a 1000pF high-voltage ceramic chip capacitor, so that serial port communication is ensured to meet the transmission rate of 115200bps, and residual pulse interference is further absorbed and suppressed.
Furthermore, the fourth-stage protection circuit adopts a nano-core micro-isolation chip NSI8141S0 and a gold anode isolation power supply module H0505S-1WR2,
the NSI8141S0 meets the requirement of 3KV isolation voltage, the ESD protection level is +/-6 KV, and the NSI8141S0 is used for isolating the TTL serial port signal of the core circuit from the signal of the front-stage interference protection circuit;
H0505S-1WR2 is used for RS-232 transceiver power supply, make the core circuit of the back stage and preceding stage interfere with the protective circuit and realize the electric isolation;
external interference has no influence on core circuit devices, and the anti-interference capability of products is improved.
Preferably, the external interference comprises fast transient pulse group interference (+ -2 KV), surge interference (+ -4 KV), electrostatic interference (+ -8 KV contact discharge), power frequency magnetic field interference and damped oscillation magnetic field interference (100A/m).
The invention also claims a serial port protection system of the data communication gateway machine of the transformer substation, which is designed aiming at the serial port protection circuit of the data communication gateway machine of the transformer substation and adopts a four-stage protection circuit:
the first stage adopts a gas discharge tube and a fixed resistor to absorb surge impact interference;
the second stage adopts a transient suppression diode to absorb residual surge impact interference and static interference;
the third stage is an RC low-pass filter circuit, so that the front-end residual pulse interference is further filtered, and the interference of serial port signals of the RS-232 transceiver is reduced;
the fourth stage is an isolation chip which is used for isolating and protecting a rear-stage core circuit.
The system is set according to the method for protecting the serial port of the substation data communication gateway machine.
The invention also claims a serial port protection device of the substation data communication gateway machine, which comprises: a four-level guard circuit, at least one memory, and at least one processor;
the four-stage protection circuit is configured according to the serial port protection method of the substation data communication gateway machine;
the at least one memory to store a machine readable program;
and the at least one processor is used for calling the machine readable program and executing the serial port protection method of the substation data communication gateway machine.
Compared with the prior art, the method for protecting the serial port of the substation data communication gateway machine has the following beneficial effects:
according to the method, the anti-interference capability of a serial port signal loop of the data communication gateway machine of the transformer substation can be improved by designing the serial port protection circuit of the data communication gateway machine of the transformer substation, and the serial port signal input by the serial port connector is protected in a multi-stage manner, so that a data communication gateway machine product can meet the index requirements of fast transient pulse group interference (+/-2 KV), surge interference (+/-4 KV), electrostatic interference (+/-8 KV contact discharge), power frequency magnetic field interference and damped oscillation magnetic field interference (100A/m) in GB/T17628.
Drawings
Fig. 1 is a schematic diagram of a serial port protection circuit of a substation data communication gateway machine according to an embodiment of the present invention.
Detailed Description
The invention is further described with reference to the following figures and specific examples.
The embodiment of the invention provides a method for protecting a serial port of a substation data communication gateway machine, which is designed aiming at a serial port protection circuit of the substation data communication gateway machine, a protection circuit is added in a TTL (transistor-transistor logic) and RS-232 serial port transceiving level conversion circuit, a four-stage protection circuit is adopted to protect an external serial port signal input by an external serial port connector, so that a serial port signal loop can withstand fast transient pulse group interference (+ -2 KV), surge interference (+ -4 KV), electrostatic interference (+ -8 KV contact discharge), power frequency magnetic field and damping oscillation magnetic field interference (100A/m), and the anti-interference capability of the data communication gateway machine is improved.
The first stage of the four-stage protection circuit is provided with 1 Gas Discharge Tube (GDT) and 2 fixed resistors and is mainly used for absorbing surge impact interference; the second stage is 2 transient suppression diodes (TVS) which are mainly used for absorbing residual surge impact interference and electrostatic interference; the third stage is an RC filter circuit which is mainly used for filtering residual pulse interference at the front end and reducing the interference to serial port signals of an RS-232 transceiver; the fourth stage is an isolation chip which is mainly used for isolating and protecting a rear-stage core circuit.
The first-stage protection circuit adopts a gas discharge tube and a fixed resistor, the outside is coupled to the line-line and line-ground high-energy surge impact absorption consumption through an RS-232 connector, most surge impact is quickly released to the ground through the casing, and residual impact is processed by the rear-stage protection circuit. In view of the characteristics of large flow, high conduction voltage, slow reaction time and continuous flow of the gas discharge tube, the first-stage protection circuit has good surge impact interference protection performance and poorer pulse interference and electrostatic interference protection capabilities.
The TVS tube is adopted by the second-stage protection circuit, residual surge interference, pulse interference and electrostatic interference of the first-stage protection circuit are absorbed, and the residual surge interference, the pulse interference and the electrostatic interference are quickly released to the ground through the casing. In view of the characteristics of high response speed, high reliability, low on-state voltage, small flow and the like of the TVS tube, the second-stage protection circuit can effectively absorb transient pulse interference and electrostatic interference, so that the interference energy in the rear-stage protection circuit is reduced to be within the bearable range of the device.
And the third-stage protection circuit adopts an RC low-pass filter circuit to further filter residual pulse interference of the second-stage protection circuit.
The fourth-stage protection circuit adopts an isolation chip, so that the rear-stage core circuit is electrically isolated from the interference protection circuit, external interference has no influence on core circuit devices, and the anti-interference capability of the product is improved.
Fig. 1 is a schematic diagram of a serial port protection circuit of a substation data communication gateway machine.
In this embodiment, the first stage protection circuit is composed of 1 three-electrode gas discharge tube GDT (3RL090M-5-S) and 2 fixed resistors (33R), wherein pins 1 and 3 of the GDT are respectively connected to TXD and RXD, and pin 2 (common pin) is connected to ground through the chassis. 3RL090M-5-S DC breakdown voltage 90V, pulse breakdown voltage 600V, common pin ground, surge impact that can effectively discharge coupling to TXD, RXD signal line. When the gas discharge tube is conducted, the through-flow pressure of the rear-stage protection circuit is reduced, and the rear-stage protection circuit is ensured to work in a safety range.
The second stage protection circuit consists of 2 TVS tubes (SMAJ15CA) and quickly discharges TXD and RXD signal line residual interference to the ground continuously through the shell. SMAJ15CA cuts off voltage 15V reversely, and limits the voltage between TXD and RXD signal lines and the chassis ground to be below 15V, thereby reducing surge, transient and electrostatic interference residual energy flowing into a rear-stage protection circuit.
The third-level protection circuit realizes an RC low-pass filter circuit by matching 2 groups of 33 ohm fixed resistors and a 1000pF high-voltage ceramic chip capacitor, ensures that serial communication meets the transmission rate of 115200bps, and further absorbs and inhibits residual pulse interference.
The fourth-stage protection circuit adopts a nano-core micro-isolation chip (NSI8141S0) and a golden rising sun isolation power supply module (H0505S-1WR2), the NSI8141S0 meets the requirement of 3KV isolation voltage, the ESD protection level is +/-6 KV, the core circuit TTL serial port signal is isolated from the front stage interference protection circuit signal, the H0505S-1WR2 is used for supplying power to the RS-232 transceiver, the rear stage core circuit is electrically isolated from the front stage interference protection circuit, external interference has no influence on core circuit devices, and the anti-interference capability of products is improved.
The method can improve the anti-interference capability of the serial port signal loop of the data communication gateway machine of the transformer substation, and the data communication gateway machine product can meet the requirement of electromagnetic compatibility test indexes in GB/T17628 by performing multi-stage protection on the serial port signal input by the serial port connector.
The embodiment of the invention also provides a substation data communication gateway serial port protection system, which is designed aiming at the substation data communication gateway serial port protection circuit and adopts a four-stage protection circuit:
the first stage adopts a gas discharge tube and a fixed resistor to absorb surge impact interference;
the second stage adopts a transient suppression diode to absorb residual surge impact interference and static interference;
the third stage is an RC low-pass filter circuit, so that the front-end residual pulse interference is further filtered, and the interference of serial port signals of the RS-232 transceiver is reduced;
the fourth stage is an isolation chip which is used for isolating and protecting a rear-stage core circuit.
The system is set according to the method for protecting the serial port of the substation data communication gateway machine in the embodiment.
The embodiment of the invention also provides a serial port protection device for the data communication gateway machine of the transformer substation, which comprises the following components: a four-level guard circuit, at least one memory, and at least one processor;
the four-stage protection circuit is configured according to the serial port protection method of the substation data communication gateway machine;
the at least one memory to store a machine readable program;
the at least one processor is configured to call the machine-readable program, and execute the serial port protection method for the substation data communication gateway machine in the foregoing embodiment.
While the invention has been shown and described in detail in the drawings and in the preferred embodiments, it is not intended to limit the invention to the embodiments disclosed, and it will be apparent to those skilled in the art that various combinations of the code auditing means in the various embodiments described above may be used to obtain further embodiments of the invention, which are also within the scope of the invention.
Claims (10)
1. The utility model provides a transformer substation data communication gateway machine serial ports protection method which characterized in that, designs to transformer substation data communication gateway machine serial ports protection circuit, increases protection circuit in RS-232 serial ports TTL and RS-232 serial ports receiving and dispatching level conversion circuit, adopts the level four protection circuit, protects by the outside serial ports signal to the external serial ports connector input, makes the serial ports signal loop resist external interference:
the first stage adopts a gas discharge tube and a fixed resistor to absorb surge impact interference;
the second stage adopts a transient suppression diode to absorb residual surge impact interference and static interference;
the third stage is an RC low-pass filter circuit, so that the front-end residual pulse interference is further filtered, and the interference of serial port signals of the RS-232 transceiver is reduced;
the fourth stage is an isolation chip which is used for isolating and protecting a rear-stage core circuit.
2. The method for protecting the serial port of the substation data communication gateway machine according to claim 1, wherein the first-stage protection circuit comprises 1 tripolar gas discharge tube and 2 fixed resistors;
the outside is coupled to the large-energy surge impact absorption consumption between the line and between the line and the ground through the RS-232 connector, most surge impact is quickly discharged to the ground through the shell, and residual impact is processed by a rear-stage protection circuit.
3. The method for protecting the serial port of the substation data communication gateway machine according to claim 2, wherein pins 1 and 3 of the tripolar gas discharge tube are respectively connected with TXD and RXD, and pin 2 is a common pin and is connected with the ground through a shell;
the three-pole gas discharge tube selects 3RL090M-5-S, 3RL090M-5-S direct current breakdown voltage 90V and pulse breakdown voltage 600V, and the common pin is grounded, so that surge impact coupled to TXD and RXD signal lines can be effectively discharged.
4. The method for protecting the serial port of the substation data communication gateway machine according to claim 2, wherein the second-stage protection circuit is 2 transient suppression diodes, and residual surge interference, pulse interference and electrostatic interference of the first-stage protection circuit are absorbed and quickly discharged to the ground through a shell.
5. The method for protecting the serial port of the substation data communication gateway machine according to claim 4, wherein the transient suppression diode is SMAJ15CA, and residual interferences of TXD and RXD signal lines are continuously and quickly released to the ground through a shell; SMAJ15CA cuts off voltage 15V reversely, and limits the voltage between TXD and RXD signal lines and the chassis ground to be below 15V, thereby reducing surge, transient and electrostatic interference residual energy flowing into a rear-stage protection circuit.
6. The method for protecting the serial port of the substation data communication gateway machine according to claim 5, wherein the third-level protection circuit is an RC low-pass filter circuit realized by matching 2 groups of 33 ohm fixed resistors and a 1000pF high-voltage ceramic chip capacitor, so that the serial port communication is ensured to meet the transmission rate of 115200bps, and the residual pulse interference is further absorbed and suppressed.
7. The method for protecting the serial port of the substation data communication gateway machine according to claim 5, wherein the fourth-level protection circuit adopts a nano-core micro-isolation chip NSI8141S0 and a Jinsheng Yang isolation power supply module H0505S-1WR2,
the NSI8141S0 meets the requirement of 3KV isolation voltage, the ESD protection level is +/-6 KV, and the NSI8141S0 is used for isolating the TTL serial port signal of the core circuit from the signal of the front-stage interference protection circuit;
H0505S-1WR2 is used for RS-232 transceiver power supply, makes the back level core circuit realize the electric isolation with preceding stage interference protection circuit.
8. The method for protecting the serial port of the substation data communication gateway machine according to any one of claims 1 to 7, wherein the external interference comprises fast transient pulse group interference, surge interference, electrostatic interference, power frequency magnetic field interference and damped oscillation magnetic field interference.
9. The utility model provides a serial ports protection system of data communication internet of transformer substation, its characterized in that, this system designs to the serial ports protection circuit of data communication internet of transformer substation, adopts level four protection circuit:
the first stage adopts a gas discharge tube and a fixed resistor to absorb surge impact interference;
the second stage adopts a transient suppression diode to absorb residual surge impact interference and static interference;
the third stage is an RC low-pass filter circuit, so that the front-end residual pulse interference is further filtered, and the interference of serial port signals of the RS-232 transceiver is reduced;
the fourth stage is an isolation chip which is used for isolating and protecting a rear-stage core circuit.
The system is arranged according to the serial port protection method of the substation data communication gateway machine of any one of claims 1 to 8.
10. The utility model provides a data communication internet of transformer substation machine serial ports protector which characterized in that includes: a four-level guard circuit, at least one memory, and at least one processor;
the four-stage protection circuit configured according to the method of any of claims 1 to 8;
the at least one memory to store a machine readable program;
the at least one processor, configured to invoke the machine readable program to perform the method of any of claims 1 to 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111218968.8A CN113904315A (en) | 2021-10-20 | 2021-10-20 | Method for protecting serial port of data communication gateway machine of transformer substation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111218968.8A CN113904315A (en) | 2021-10-20 | 2021-10-20 | Method for protecting serial port of data communication gateway machine of transformer substation |
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| Publication Number | Publication Date |
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| CN113904315A true CN113904315A (en) | 2022-01-07 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202111218968.8A Pending CN113904315A (en) | 2021-10-20 | 2021-10-20 | Method for protecting serial port of data communication gateway machine of transformer substation |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114866160A (en) * | 2022-05-27 | 2022-08-05 | 安徽南瑞中天电力电子有限公司 | Isolation protection circuit, module and chip of RS485 chip in acquisition terminal |
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2021
- 2021-10-20 CN CN202111218968.8A patent/CN113904315A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114866160A (en) * | 2022-05-27 | 2022-08-05 | 安徽南瑞中天电力电子有限公司 | Isolation protection circuit, module and chip of RS485 chip in acquisition terminal |
| CN114866160B (en) * | 2022-05-27 | 2024-02-06 | 安徽南瑞中天电力电子有限公司 | Isolation protection circuit, module and chip of RS485 chip in acquisition terminal |
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