CN212749169U - Non-contact type electrified detection device for mechanical characteristics of circuit breaker - Google Patents
Non-contact type electrified detection device for mechanical characteristics of circuit breaker Download PDFInfo
- Publication number
- CN212749169U CN212749169U CN202022231902.XU CN202022231902U CN212749169U CN 212749169 U CN212749169 U CN 212749169U CN 202022231902 U CN202022231902 U CN 202022231902U CN 212749169 U CN212749169 U CN 212749169U
- Authority
- CN
- China
- Prior art keywords
- unit
- circuit breaker
- circuit
- sensor
- electric field
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Abstract
A non-contact type charged detection device for mechanical characteristics of a circuit breaker relates to a non-contact data acquisition unit of a data circuit breaker, and the non-contact data acquisition unit comprises a speed sampling sensor, a speed sampling shaping circuit unit, a current sampling sensor, a current signal processing circuit unit, an external electric field sensor, an electric field signal processing circuit unit and a CPU (central processing unit), wherein the CPU comprises a high-speed single chip microcomputer, and the CPU is further connected with a peripheral expansion display unit, a keyboard unit, a storage unit, a communication unit and a power supply unit. Compared with the prior art, the utility model realizes the mechanical detection of the high-voltage circuit breaker by measuring the change signal of the additional magnetic field detected by the sensor when the contact of the circuit breaker acts based on the magnetic field and the electric field induction sensor; through the mechanical detection equipment of the circuit breaker, the loaded mechanical data of the circuit breaker can be acquired when the electrified state is switched to the power failure state, so that the correlation between the power failure data and the electrified data can be established, and the actual operation condition of the tested circuit breaker can be truly evaluated.
Description
Technical Field
The utility model relates to a high voltage direct current transmission detects technical field, in particular to electrified detection device of non-contact's circuit breaker mechanical properties.
Background
In recent years, the rapid development of power systems brings new opportunities and challenges to the power industry, so people pay more and more attention to the safety and stability of the operation of power equipment. The high-voltage circuit breaker is one of the most important switching appliances in a power system, and can be used for switching the operation mode during normal operation, so that equipment or lines are put into or quit operation, and the switching control function is realized; when a certain device or line has a fault, the fault can be quickly removed, and the normal operation of the power grid is ensured. Therefore, the high voltage circuit breaker plays an important role in the power system, and the reliability of its operation is directly related to the safe operation of the power system.
The existing developed on-line measurement technology of the circuit breaker is obtained by modifying a power failure maintenance technology, is not an on-line measurement technology which is really researched and developed aiming at state maintenance, still belongs to an off-line measurement technology, the test result and the judgment basis of the on-line measurement technology still use a maintenance guide rule and circuit breaker factory data as standards, and neglect the product operation environment, the operation state, the load and the maintenance condition, so that the judgment standard range is wider, and the actual operation condition of the tested circuit breaker cannot be really judged.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a non-contact's electrified detection device of circuit breaker mechanical properties to solve the technical defect that the actual behavior of circuit breaker under test can't really be judged to the online maintenance of circuit breaker among the prior art.
The technical scheme of the utility model is realized like this:
the utility model provides a electrified detection device of non-contact circuit breaker mechanical properties, includes data circuit breaker non-contact data acquisition unit, data circuit breaker non-contact data acquisition unit includes:
the circuit comprises a speed sampling sensor and a speed sampling shaping circuit unit, wherein the speed sampling sensor is used for acquiring opening and closing speed analog parameters of a contact of a circuit breaker, and the speed sampling shaping circuit unit is used for converting the opening and closing speed analog parameters into digital signals and transmitting the digital signals to a CPU (central processing unit);
the current sampling sensor is used for collecting secondary current, and the current signal processing circuit unit is used for processing secondary current signals and transmitting the processed current signal data to the CPU unit;
the device comprises an external electric field sensor and an electric field signal processing circuit unit, wherein the external electric field sensor is used for collecting electric field intensity data around a high-voltage lead, and the electric field signal processing circuit unit processes the electric field intensity data and then transmits the processed electric field intensity data to a CPU (central processing unit);
the CPU unit comprises a high-speed single chip microcomputer, the CPU unit is further connected with a peripheral extension display unit, a keyboard unit, a storage unit, a communication unit and a power supply unit, and the speed sampling and shaping circuit unit, the current signal processing circuit unit and the electric field signal processing circuit unit are also respectively connected with the CPU unit.
Preferably, the speed sampling sensor adopts a non-contact eddy current sensor, the speed sampling shaping circuit unit processes a circuit breaker contact opening and closing signal sent by the non-contact eddy current sensor and converts the signal into a counting pulse and an addition and subtraction control signal, a counter in the CPU unit is responsible for counting, and the CPU unit reads the count value of the counter periodically and stores the count value in the storage unit in sequence.
Preferably, the current sampling sensor is a hall current sensor, the current signal processing circuit unit includes an amplifying circuit, a filter circuit and an a/D digital-to-analog conversion circuit, and a current signal acquired by the current sampling sensor is amplified and filtered, and then sent to the a/D digital-to-analog conversion circuit to be converted into a digital circuit, and then sent to the CPU unit.
Preferably, the external electric field sensor includes three paths, and the three paths of electric field sensors are respectively connected to the CPU unit.
Preferably, the speed sampling shaping circuit unit adopts a speed sampling chip U-STC15W 201S/016-Z.
Preferably, the A/D conversion circuit adopts an ADS7864 chip.
Preferably, the SST25VF016 storage chip is selected as the storage unit.
Preferably, the communication unit adopts a core device as a CH340 chip, and is configured to transmit data processed by the CPU unit to an upper computer.
Compared with the prior art, the utility model discloses there is following beneficial effect:
the utility model discloses a non-contact electrified detection device of circuit breaker mechanical properties, to outdoor and GIS high voltage circuit breaker, through based on magnetic field, electric field induction sensor, through measuring the change signal of the additional magnetic field that the circuit breaker contact detected when the action, realize the detection of high voltage circuit breaker mechanicalness; the correlation analysis research of the live and power failure test data of the circuit breaker is realized. Through the mechanical detection equipment of the circuit breaker, the mechanical data of the circuit breaker with load when the live state is switched to the power failure state can be acquired, so that data support is provided for correlation research between the live data of the circuit breaker and the power failure measurement data, the correlation between the power failure data and the live data can be established, and the actual operation condition of the detected circuit breaker can be really evaluated.
Drawings
Fig. 1 is a schematic circuit block diagram of the non-contact type circuit breaker mechanical property live detection device of the present invention;
fig. 2 is a schematic circuit diagram of the speed sampling shaping circuit unit of the present invention;
FIG. 3 is a schematic view of the counting direction determination method of the present invention;
fig. 4 is a schematic circuit diagram of the amplifying circuit and the filter circuit of the present invention;
FIG. 5 is a schematic circuit diagram of the A/D DAC circuit of the present invention;
FIG. 6 is a schematic circuit diagram of the electric field signal processing circuit unit of the present invention;
fig. 7 is a schematic circuit diagram of the real-time clock of the present invention;
FIG. 8 is a schematic circuit diagram of a memory cell according to the present invention;
fig. 9 is a schematic circuit diagram of the communication unit of the present invention;
fig. 10 is a block diagram of the software design of the present invention.
Detailed Description
The present invention will be described more fully and clearly with reference to the accompanying drawings, which are incorporated in and constitute a part of this specification.
As shown in fig. 1, a non-contact type device for detecting mechanical characteristics of a circuit breaker with electricity comprises a data circuit breaker non-contact data acquisition unit, wherein the data circuit breaker non-contact data acquisition unit comprises:
the circuit comprises a speed sampling sensor and a speed sampling shaping circuit unit, wherein the speed sampling sensor is used for acquiring opening and closing speed analog parameters of a contact of a circuit breaker, and the speed sampling shaping circuit unit is used for converting the opening and closing speed analog parameters into digital signals and transmitting the digital signals to a CPU (central processing unit);
the current sampling sensor is used for collecting secondary current, and the current signal processing circuit unit is used for processing secondary current signals and transmitting the processed current signal data to the CPU unit;
the device comprises an external electric field sensor and an electric field signal processing circuit unit, wherein the external electric field sensor is used for collecting electric field intensity data around a high-voltage lead, and the electric field signal processing circuit unit processes the electric field intensity data and then transmits the processed electric field intensity data to a CPU (central processing unit);
the CPU unit comprises a high-speed single chip microcomputer, the CPU unit is further connected with a peripheral extension display unit, a keyboard unit, a storage unit, a communication unit and a power supply unit, and the speed sampling and shaping circuit unit, the current signal processing circuit unit and the electric field signal processing circuit unit are also respectively connected with the CPU unit.
As shown in fig. 2, the speed sampling sensor is a non-contact eddy current sensor, the speed sampling shaping circuit unit processes a circuit breaker contact opening and closing signal sent by the non-contact eddy current sensor, and converts the signal into a counting pulse and an addition and subtraction control signal, a counter inside the CPU unit is responsible for counting, and the CPU unit reads the count value of the counter periodically and stores the count value in the storage unit in sequence.
As shown in fig. 3, in order to improve the immunity to interference of the signal transmission of the contactless eddy current sensor, the angle-changed signal is transmitted by 2 sets of differential signals. The two groups of differential signals are respectively defined as A +/A-, B +/B-, the level is HTL, the differential voltage can reach 12V, under the condition, the signal transmission distance of the eddy current sensor can reach more than 1 kilometer, and the anti-interference performance is very strong.
As shown in fig. 4 and 5, the current sampling sensor is a hall current sensor, the current signal processing circuit unit includes an amplifying circuit, a filtering circuit and an a/D digital-to-analog conversion circuit, and a current signal acquired by the current sampling sensor is amplified and filtered, and then sent to the a/D digital-to-analog conversion circuit to be converted into a digital circuit, and then sent to the CPU unit.
The A/D conversion circuit adopts an ADS7864 chip. The ADS7864 is a dual 12-bit, 500kHz analog-to-digital (a/D) converter with 6 differential input channels, divided into 3 pairs, for high speed synchronous signal acquisition. The inputs to the sample and hold amplifier are fully differential and hold to the inputs of the a/D converter. This provides a common mode rejection ratio of 80dB at 50kHz, which is important in high noise environments. The ADS7864 provides a parallel interface and control input to minimize software overhead, with the output data per channel being 16-bit words (address and data) wide. In this embodiment, the maximum value of the control current is 25A, and the AD resolution is 12 bits, so that the minimum current resolution can reach 25A/4095 to 0.006A, and the current analysis requirement is satisfied.
As shown in fig. 6, the external electric field sensor includes three paths, and the external electric field sensor converts the electric field strength into a high level and a low level, where the high level represents an open state and the low level represents a close state. The three external electric field sensors are respectively connected to the CPU unit. The traditional time testing method is that one side of the breaker is in short circuit and grounded, and the ABC three phases on the other side of the breaker are respectively connected with the input of an instrument fracture. When the breaker is opened, the input end of the fracture is equivalent to a suspended state, and a pull-up resistor is arranged in the instrument and is equivalent to a high level; when the breaker is switched on, the fracture input is pulled down and is in a low level. That is to say, the fracture input of the instrument can be connected with the electric field sensor to realize live-line test, and can also be directly connected with a test wire to test by using a traditional method, so that the application occasion of the sampling terminal is widened.
Three-way fracture state can be gathered in the fracture sampling of tester, and DK01-03 corresponds ABC three-phase fracture input signal respectively, and when the fracture was unsettled or high level, K00-K02 output TTL high level, and singlechip (CPU unit) IO can read the fracture state. When the break is pulled low, K00-K02 outputs a low level. The diode and the capacitor are mainly used for protection and filtering, the capacitor mainly has 2 functions, one function is to realize the electrical isolation of a fracture channel and the single chip microcomputer and protect the single chip microcomputer from being broken down or interfered by induction electricity, and the other function is to realize the conversion of level and convert high voltage into TTL level so as to meet the voltage requirement of a single chip microcomputer interface.
When the test is started, the single chip microcomputer reads IO connected with fracture output signals in a fixed period, the minimum reading period is 0.1ms, and the read fracture states are sequentially stored in the RAM by the single chip microcomputer.
The speed sampling shaping circuit unit adopts a speed sampling chip U-STC15W 201S/016-Z.
As shown in fig. 7 and 8, the storage unit is an SST25VF016 storage chip, and when the tester collects data, the tester needs to record the date and time of the breaker operation, so that a real-time clock with a battery is integrated in the collection terminal. In addition, the test data of the tester needs to be stored for a long time, so the tester also integrates a nonvolatile FLASH memory for storing the data,
the real time clock is PCF8563 real time clock chip. The PCF8563 is an industrial grade multifunctional clock/calendar chip PCF8563 with an I2C bus interface function and extremely low power consumption, and can complete various complex timing services by a timer function, a clock output function and an interrupt output function of various alarming functions, and even can provide a watchdog function for a single chip microcomputer. The internal clock circuit, the internal oscillation circuit, the internal low voltage detection circuit (1.0V) and the two-wire system I2C bus communication mode not only make the peripheral circuit and the conciseness, but also increase the reliability of the chip, and the embedded word address register can automatically generate increment after reading and writing data each time, and the PCF8563 which is taken as the clock chip also solves the problem in 2000 years, and is widely applied to the product fields of portable instruments such as electric meters, water meters, gas meters, telephones, fax machines and the like, instrument instruments and meters powered by batteries and the like. The chip provides automatic timing function for second, minute, hour, day, month and year, and also provides the functions of minute alarm, hour alarm, day alarm, etc.
The real-time clock chip selects the CR2032 button cell as the power, under the normal condition, can supply the chip to work for 5 years, under the instrument circular telegram circumstances, because supply voltage VDD is higher than battery voltage, the chip power supply is supplied power by the lithium cell of sampling terminal. The communication mode of the clock chip and the single chip microcomputer is I2C, and occupation of an IO port line is reduced under the condition that the communication speed is met.
Due to the processing error in the period, the 32768Hz crystal oscillator may have frequency error, and may cause timing error after long-time operation, so that whether the real clock of the sampling terminal is accurate or not can be checked at intervals, and if the real clock has error, the data storage module can be adjusted and calibrated through the human-computer interface of the sampling terminal.
As shown in fig. 9, the communication unit is used for transmitting the data processed by the CPU unit to the upper computer. After the detector stores a plurality of data, the data need to be transmitted and stored to a computer. The core device of the communication unit is a CH340 chip. The CH340 is a switching chip of a USB bus, and implements a USB to serial function. So that the sampling terminals can be directly connected by a USB cable.
The RXD/TXD signal of the CH340 is connected with a serial port IO of the single chip microcomputer. And a CH340 driving program is installed on the computer, so that the function of accessing the sampling terminal by the PC is realized. The CH340 has a separate transmit-receive buffer built therein to support simplex, half-duplex or full-duplex asynchronous serial communications. The serial data comprises 1 low-level start bit, 5, 6, 7 or 8 data bits and 1 or 2 high-level stop bits, and supports odd check/even check/mark check/blank check. CH340 supports the common communication baud rate: 50. 75, 100, 110, 134.5, 150, 300, 600, 900, 1200, 1800, 2400, 3600, 4800, 9600, 14400, 19200, 28800, 33600, 38400, 56000, 57600, 76800, 115200, 128000, 153600, 230400, 460800, 921600, 1500000, 2000000, and the like. The Baud rate error of the serial port sending signal is less than 0.3%, and the allowable Baud rate error of the serial port receiving signal is not less than 2%. Under the Windows operating system of the computer end, the driver program of CH340 can imitate the standard serial port, so most of the original serial port application programs are completely compatible, and usually do not need to make any modification.
As shown in fig. 10, the utility model discloses still include the software unit, shown software unit adopts the modularization, and every function accomplishes respective function, conveniently realizes that the group compiles in coordination. The system is mainly divided into the following modules.
And the test setting is used for setting test modes, such as circuit breaker speed definition, sensor type selection, acquisition terminal trigger mode, single sampling duration and other parameters.
And data sampling, wherein the module is a core module, and in the sampling process, a sampling terminal samples signals at the frequency of 10kHz and mainly collects main parameters such as fracture states, current values and counting values of a sensor counting module. And after the data sampling is finished, the CPU automatically calculates various parameters according to the test setting, and after all the parameters are calculated, the parameters are automatically displayed on an LCD display of the sampling terminal. The user may switch to view the data.
The data storage module has two calling modes, one mode is an automatic mode, and in the automatic mode, the data is stored once every time the sampling terminal samples; the other mode is a manual mode, in which the sampling terminal does not automatically store data, but an operator autonomously selects whether to store data.
And the data reading module is used for operating the reading module to select the data to be checked if the data stored in the acquisition terminal needs to be checked, reading the data into the memory by the CPU after selecting a certain group of data, and automatically displaying the data on the LCD after calculating parameters.
The time and date setting module is used for acquiring the real-time clock built in the terminal, timing errors may exist after long-time timing, and if the timing errors occur, the date and time of the real-time clock built in the acquisition terminal can be modified through the time and date setting interface, so that the accuracy of the data timestamp is ensured.
5.2 comprehensive evaluation of the mechanicalness of the Circuit breaker
The health state of the circuit breaker is obtained mainly by two means of a power failure test and online monitoring, the power failure test has strict maintenance regulations for judgment, the online monitoring has no clear judgment standard, the judgment standard of the power failure test can only be used as a judgment basis at present, but the live operation and the power failure state of the circuit breaker are completely different. In order to comprehensively master the mechanical condition of the circuit breaker, a correlation mode of power failure data and live data of the circuit breaker needs to be established, and a data processing technology is relied on, so that the mechanical property of the circuit breaker is effectively evaluated and predicted.
By integrating the circuit structure and the principle of the utility model, the mechanical detection of the high-voltage circuit breaker can be realized by measuring the change signal of the additional magnetic field detected by the sensor when the circuit breaker contact acts based on the magnetic field and the electric field induction sensor aiming at outdoor and GIS high-voltage circuit breakers; the correlation analysis research of the live and power failure test data of the circuit breaker is realized. Through the mechanical detection equipment of the circuit breaker, the mechanical data of the circuit breaker with load when the live state is switched to the power failure state can be acquired, so that data support is provided for correlation research between the live data of the circuit breaker and the power failure measurement data, the correlation between the power failure data and the live data can be established, and the actual operation condition of the detected circuit breaker can be really evaluated.
Claims (8)
1. The utility model provides a charged detection device of non-contact circuit breaker mechanical properties which characterized in that: including data circuit breaker non-contact data acquisition unit, data circuit breaker non-contact data acquisition unit includes:
the circuit comprises a speed sampling sensor and a speed sampling shaping circuit unit, wherein the speed sampling sensor is used for acquiring opening and closing speed analog parameters of a contact of a circuit breaker, and the speed sampling shaping circuit unit is used for converting the opening and closing speed analog parameters into digital signals and transmitting the digital signals to a CPU (central processing unit);
the current sampling sensor is used for collecting secondary current, and the current signal processing circuit unit is used for processing secondary current signals and transmitting the processed current signal data to the CPU unit;
the device comprises an external electric field sensor and an electric field signal processing circuit unit, wherein the external electric field sensor is used for collecting electric field intensity data around a high-voltage lead, and the electric field signal processing circuit unit processes the electric field intensity data and then transmits the processed electric field intensity data to a CPU (central processing unit);
the CPU unit comprises a high-speed single chip microcomputer, the CPU unit is further connected with a peripheral extension display unit, a keyboard unit, a storage unit, a communication unit and a power supply unit, and the speed sampling and shaping circuit unit, the current signal processing circuit unit and the electric field signal processing circuit unit are also respectively connected with the CPU unit.
2. The non-contact type charged detector for mechanical characteristics of circuit breaker according to claim 1, wherein the speed sampling sensor is a non-contact eddy current sensor, the speed sampling and shaping circuit unit processes the opening and closing signals of the contacts of the circuit breaker sent by the non-contact eddy current sensor and converts the signals into counting pulses and up and down control signals, a counter inside the CPU unit is responsible for counting, and the CPU unit reads the counting values of the counter periodically and stores the counting values in the storage unit in sequence.
3. The device for detecting mechanical characteristics of a non-contact breaker as claimed in claim 1, wherein the current sampling sensor is a hall current sensor, the current signal processing circuit unit includes an amplifying circuit, a filtering circuit and an a/D digital-to-analog conversion circuit, and a current signal collected by the current sampling sensor is amplified and filtered, and then sent to the a/D digital-to-analog conversion circuit to be converted into a digital circuit, and then sent to the CPU unit.
4. The apparatus for detecting mechanical characteristics of non-contact type circuit breaker with electricity as claimed in claim 1, 2 or 3, wherein said external electric field sensor comprises three electric field sensors, each of which is connected to the CPU unit.
5. The apparatus of claim 1, wherein the speed sampling and shaping circuit unit employs a speed sampling chip U-STC15W 201S/016-Z.
6. The apparatus for detecting the electrification of mechanical characteristics of a non-contact type circuit breaker according to claim 3, wherein the A/D conversion circuit employs an ADS7864 chip.
7. The apparatus for detecting the mechanical characteristics of the non-contact type circuit breaker according to claim 1, wherein the storage unit is an SST25VF016 storage chip.
8. The apparatus according to claim 1, wherein the communication unit uses a CH340 chip as a core device, and the communication unit is configured to transmit data processed by the CPU unit to an upper computer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022231902.XU CN212749169U (en) | 2020-10-09 | 2020-10-09 | Non-contact type electrified detection device for mechanical characteristics of circuit breaker |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022231902.XU CN212749169U (en) | 2020-10-09 | 2020-10-09 | Non-contact type electrified detection device for mechanical characteristics of circuit breaker |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212749169U true CN212749169U (en) | 2021-03-19 |
Family
ID=74990854
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022231902.XU Active CN212749169U (en) | 2020-10-09 | 2020-10-09 | Non-contact type electrified detection device for mechanical characteristics of circuit breaker |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212749169U (en) |
-
2020
- 2020-10-09 CN CN202022231902.XU patent/CN212749169U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN201465279U (en) | Wireless multi-channel vibration data synchronous acquisition system supplied with power by battery | |
| RU2613130C1 (en) | Automated equipment monitoring device for electric substation | |
| CN103792939B (en) | Absolute value encoder signal measurement and control instrument and its detection method | |
| CN204304613U (en) | II type electric energy efficiency office terminal and system | |
| CN110187193B (en) | Dielectric loss monitoring system and method based on total-station voltage transformer stability judgment | |
| CN102611201A (en) | On-line monitoring system of power distribution cabinet | |
| CN106066465A (en) | A kind of Watt-hour meter's field test remote impulse module and method of calibration thereof | |
| CN201130428Y (en) | Optic fiber gyroscope data acquisition model based on FPGA | |
| CN104625276A (en) | On-line operation parameter real-time monitoring system and method of spark machine | |
| CN204794352U (en) | Intelligence electric power monitored control system | |
| CN212749169U (en) | Non-contact type electrified detection device for mechanical characteristics of circuit breaker | |
| CN200944111Y (en) | Water quality analyzer with wireless communication function | |
| CN209148803U (en) | Intelligent casing on-Line Monitor Device | |
| CN112526332A (en) | Non-contact type electrified detection device for mechanical characteristics of circuit breaker | |
| CN203658883U (en) | Temperature and humidity monitoring system for power battery pack of electric vehicle | |
| CN200989917Y (en) | Voltage sensor | |
| CN202916360U (en) | Switching value tester | |
| CN205353657U (en) | Diagnosis of multi -functional communication interface data and signal driver card | |
| CN204304614U (en) | I type electric energy efficiency office terminal and system | |
| CN101776773B (en) | Testing system of ship weather instrument | |
| CN201561863U (en) | Data quality assurance device for mining equipment fault diagnosis | |
| CN205941876U (en) | Long -range pulse module of on --spot check -up of electric energy meter | |
| CN203981661U (en) | A kind of portable water quality on-line detector | |
| CN208270729U (en) | Breaker mechanic property comprehensive detection system based on ARM controller | |
| CN102243198A (en) | High-precision digitized cotton moisture intelligent detector |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |