CN102842951B - Low voltage loop-closing selective-tripping system - Google Patents
Low voltage loop-closing selective-tripping system Download PDFInfo
- Publication number
- CN102842951B CN102842951B CN201110174401.5A CN201110174401A CN102842951B CN 102842951 B CN102842951 B CN 102842951B CN 201110174401 A CN201110174401 A CN 201110174401A CN 102842951 B CN102842951 B CN 102842951B
- Authority
- CN
- China
- Prior art keywords
- relay
- air switch
- low
- pressure ring
- tripping system
- 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
- 238000007363 ring formation reaction Methods 0.000 claims description 18
- 230000009977 dual effect Effects 0.000 claims description 8
- 238000004804 winding Methods 0.000 claims description 7
- 230000007935 neutral effect Effects 0.000 abstract 1
- 238000000034 method Methods 0.000 description 7
- 150000001875 compounds Chemical class 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 230000009191 jumping Effects 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 238000005259 measurement Methods 0.000 description 5
- 230000009471 action Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000005057 refrigeration Methods 0.000 description 1
Abstract
The invention provides a low voltage loop-closing selective-tripping system, comprising auxiliary connection points of three air switches, a relay and a selective-tripping switch, wherein the relay comprises three normally open contacts; the selective-tripping switch comprises three groups of connection points, and moreover, only one group of connection points is located in the on-state; the auxiliary connection points of the three air switches are connected in series in order; the auxiliary connection point of the first air switch is connected with a live wire of a power supply source; the auxiliary connection point of the third air switch is connected in series with the first end of a coil of the relay; the second end of the coil of the relay is connected with a neutral wire of the power supply source; the three normally open contacts of the relay are connected with three input connection points in the three groups of connection points of the selective-tripping switch respectively; and three output connection points in the three groups of connection points of the selective-tripping switch are connected with opening coils of three opening loops of the three air switches respectively. With the adoption of the low voltage loop-closing selective-tripping system, the problem of voltage flicker of momentary interruption during the switching operation can be solved; the power can be supplied reliably; and the personal safety of operators can be guaranteed.
Description
Technical field
The present invention relates to power supply technique field, be specifically related to a kind of low-pressure ring-closing selective tripping system.
Background technology
The high pressure user who has at present many duplicate supplys and many power supplys, these users are very high to the quality requirement of power supply reliability and power supply.Figure 1 shows that the main wiring diagram of the dual power supply system of prior art mesolow single-trunk segmental wiring form, comprising First air switch QF1, second air switch QF2 and the 3rd air switch QF3, wherein First air switch QF1 and second air switch QF2 are respectively service entrance switch, and the 3rd air switch QF3 is bus connection switch.This dual power supply system is carried out in grid switching operation process, can there is the voltage flicker of instantaneous power-off in user's busbar voltage.The voltage flicker of instantaneous power-off is very large on the impact of modernization electric equipment, and every electric equipment that computer chip is housed all can quit work, and after these electric equipments quit work, user will be produced to very serious consequence.Many high-power gas charging illuminating lamp instantaneous power-off numbers millisecond quit work, again after incoming call, need etc. can restart for several minutes, this produces greatly challenge to important place electric consumption on lighting, some refrigeration plants are also very sensitive to the voltage flicker of instantaneous power-off, even after instantaneous power-off, can damage.
For the impact that prevents that the voltage flicker of instantaneous power-off from causing user, the measure of generally taking is that contact is in short-term carried out in many high pressure users' high-pressure side, then in the situation that low-pressure side is got in touch with in short-term, allow and need the equipment having a power failure to depart from power supply, to avoid occurring in back brake process the voltage flicker of instantaneous power-off.
According to the aforesaid way of prior art, because the voltage difference of high-pressure side and low-pressure side is larger, can make circulation surpass protection definite value, cause mains side protection to be moved, original unnecessary user occurs to have a power failure, simultaneously, larger circulation can make the circuit of double power-supply system occur the overload that can not restrain oneself in short-term, this grid switching operation can cause equipment burnout because of operating personnel's misoperation, and increased the difficulty of scheduling, the probability that makes staff that electric shock accidents occur increases, and it is elongated that this mode also can make single supply system originally become time of double power-supply system, cause the malfunctioning or sensitivity of some protective devices to change.
In the prior art, the mode of getting in touch with in short-term by high-pressure side and low-pressure side avoids occurring in grid switching operation process the voltage flicker of instantaneous power-off, causing can not reliable power supply and can not guarantee operating personnel's personal safety for these problems, not yet to propose at present effective solution.
Summary of the invention
Main purpose of the present invention is to provide a kind of low-pressure ring-closing selective tripping system, to solve the mode of getting in touch with in short-term by high-pressure side and low-pressure side in prior art, the voltage flicker of instantaneous power-off occurs in grid switching operation process, causing can not reliable power supply and the problem that can not guarantee operating personnel's personal safety.
To achieve these goals, the invention provides a kind of low-pressure ring-closing selective tripping system, for the choosing of three of the dual power supply system of single-trunk segmental wiring form air switches being carried out after cyclization, jump control.
Low-pressure ring-closing selective tripping system of the present invention comprises: the auxiliary contact of three air switches; Relay, comprises three normally opened contacts; Select TRIP, comprise three groups of contacts and only have one group of contact in on-state at every turn;
In described three air switches, the auxiliary contact of First air switch, second air switch and the 3rd air switch is connected in series successively, wherein the auxiliary contact of First air switch and the power firestreak of described low-pressure ring-closing selective tripping system are connected, the first end of the 3rd auxiliary contact of air switch and the coil of described relay is connected in series mutually, and the second end of the coil of described relay is connected with zero-power line;
Three normally opened contacts of described relay are connected with three input contacts in described three groups of contacts that select TRIP respectively, and three output contacts in described three groups of contacts that select TRIP are connected with the switching winding of three sub-gate circuits of described three air switches respectively.
Further, between the auxiliary contact of described First air switch and described power firestreak, be also provided with fuse.
Further, described relay also comprises the 4th normally opened contact, is connected, for sending cyclization signal with relay indicating light.
Further, described relay is AC intermediate relay.
Further, the rated voltage of described AC intermediate relay is AC (alternating current) 220V.
Further, described AC intermediate relay is the multiconductor AC intermediate relay of electromagnetic solenoid type structure.
Further, described three air switches are universal air switch.
According to technical scheme of the present invention, low-pressure ring-closing selective tripping system of the present invention adopts low pressure cyclization to start, automatically will select after tripping cyclization the grid switching operation mode of a switch in three switches of jumping, not only avoid the generation of the voltage flicker of instantaneous power-off, also guaranteed the reliability of power supply and operating personnel's personal safety.
Accompanying drawing explanation
Figure of description is used to provide a further understanding of the present invention, forms the application's a part, and schematic description and description of the present invention is used for explaining the present invention, does not form inappropriate limitation of the present invention.In the accompanying drawings:
Fig. 1 is the main wiring diagram of the dual power supply system of prior art mesolow single-trunk segmental wiring form;
Fig. 2 starts the schematic diagram in loop according to the cyclization of the low-pressure ring-closing selective tripping system of the embodiment of the present invention; And
Fig. 3 jumps according to the choosing of the low-pressure ring-closing selective tripping system of the embodiment of the present invention schematic diagram of carrying out loop.
Embodiment
It should be noted that, in the situation that not conflicting, embodiment and the feature in embodiment in the application can combine mutually.Describe below with reference to the accompanying drawings and in conjunction with the embodiments the present invention in detail.
In the present embodiment, low-pressure ring-closing selective tripping system of the present invention is for carrying out the choosing jumping control after cyclization to the First air switch QF1 of the dual power supply system of Fig. 1 mesolow single-trunk segmental wiring form, second air switch QF2 and the 3rd air switch QF3.
In the present embodiment, low-pressure ring-closing selective tripping system of the present invention comprises: cyclization starts loop and execution loop is jumped in choosing.
Fig. 2 starts the schematic diagram in loop according to the cyclization of the low-pressure ring-closing selective tripping system of the embodiment of the present invention.
As shown in Figure 2, this cyclization startup loop comprises:
The auxiliary contact 21 of the First air switch QF1 of serial connection, second auxiliary contact 22 of air switch QF2 are, the auxiliary contact 23 of the 3rd air switch QF3 successively.
Relay coil 24, one end is connected in series mutually with the auxiliary contact 23 of the 3rd air switch QF3, and the other end is connected with zero-power line N.
Fuse 25, one end is connected in series mutually with the auxiliary contact 21 of First air switch QF1, and the other end is connected with the live wire L of low-pressure ring-closing selective tripping system of the present invention.
In the present embodiment, only at three air switches during all at closing position, the auxiliary contact of three air switches is simultaneously closed, and the cyclization of the low-pressure ring-closing selective tripping system of the embodiment of the present invention shown in Fig. 2 starts loop and just connects.
Fig. 3 jumps according to the choosing of the low-pressure ring-closing selective tripping system of the embodiment of the present invention schematic diagram of carrying out loop.
As shown in Figure 3, this choosing is jumped and is carried out three groups of contacts that loop mainly comprises four normally opened contacts of relay and selects TRIP.
Wherein, first normally opened contact 31 of relay is connected in series mutually with selecting the input contact A of first group of contact 35 of TRIP, and the output contact a of first group of contact 35 is connected with the switching winding of the sub-gate circuit of First air switch QF1.
Wherein, second normally opened contact 32 of relay is connected in series mutually with selecting the input contact B of second group of contact 36 of TRIP, and the output contact b of second group of contact 36 is connected with the switching winding of the sub-gate circuit of second air switch QF2.
Wherein, the 3rd normally opened contact 33 of relay is connected in series mutually with selecting the input contact C of the 3rd group of contact 37 of TRIP, and the output contact c of the 3rd group of contact 37 is connected with the switching winding of the sub-gate circuit of the 3rd air switch QF3.
Wherein, the 4th normally opened contact 34 of relay, as standby normally opened contact, can be connected with relay indicating light, for sending cyclization signal.
In the present embodiment, relay is the multiconductor AC intermediate relay of electromagnetic solenoid type structure, and its rated voltage is AC220V, is not more than 50 milliseconds the operate time under rated voltage, and scope operate time that sub-gate circuit is connected in actual measurement is 31～33 milliseconds.
In the present embodiment, First air switch QF1, second air switch QF2 and the 3rd air switch QF3 can be all MT series, the serial universal low-voltage air switch of E, electric pressure is 220V, and the actual measurement opening time scope of these three air switches is 50～51 milliseconds.
In the present embodiment, selecting TRIP is universal seclector, in its three groups of contacts, only has one group of contact in on-state at every turn.
In the present embodiment, in the normal course of operation of the dual power supply system shown in Fig. 1, First air switch QF1 and second air switch QF2 are in closing position, and the 3rd air switch QF3 is in open position.After closing the ring, low-pressure ring-closing selective tripping system of the present invention can select jumps First air switch QF1 or second air switch QF2.According to the needs of dual power supply system, low-pressure ring-closing selective tripping system of the present invention can have multiple choosing to jump compound mode, specifically sees the following form one:
Table one: compound mode is jumped in the choosing of low-pressure ring-closing selective tripping system
In upper table one, comprised altogether six kinds of choosings and jumped compound mode, be explained as follows respectively:
Compound mode is jumped in the first choosing: under initial condition, First air switch QF1 and second air switch QF2 are in closing position, the 3rd air switch QF3 is in open position, if the switch that choosing is jumped is First air switch QF1, the process of ring-closing selective tripping is as follows:
First, will select TRIP to jumping QF1 position, connect the first group of contact 35 that selects TRIP;
Secondly, the 3rd the air switch QF3 that close, the auxiliary contact 21 of First air switch QF1, second auxiliary contact 22 of air switch QF2 and the auxiliary contact 23 of the 3rd air switch QF3 are in closure state, and cyclization starts loop and connects;
Finally, relay coil 24 energisings, make four normally opened contacts of relay simultaneously closed, owing to selecting first group of contact 35 of TRIP in on-state, be attached thereto the switching winding energising of sub-gate circuit of First air switch QF1, the action of separating brake iron core, makes the automatic tripping of main contact of First air switch QF1.
In the present embodiment, can according to choosing, jump the principle of First air switch QF1, complete six kinds of choosings of automatic jump selection the second to the and jump compound mode.
In the present embodiment, after the selected jumping of air switch, often need to recover former operational mode, the former operational mode that compound mode is jumped in the first choosing that recovers above-mentioned selected jumping of take describes as example, and process is as follows:
First, will select TRIP to jumping QF3 position, connect the 3rd group of contact 37 that selects TRIP;
Secondly, the First air switch QF1 that closes, the auxiliary contact 21 of First air switch QF1, second auxiliary contact 22 of air switch QF2 and the auxiliary contact 23 of the 3rd air switch QF3 are in closure state, and cyclization starts loop and connects;
Finally, relay coil 24 energisings, make four normally opened contacts of relay simultaneously closed, owing to selecting the 3rd group of contact 37 of TRIP in on-state, be attached thereto the switching winding energising of sub-gate circuit of the 3rd air switch QF3, the action of separating brake iron core, makes the automatic tripping of main contact of the 3rd air switch QF3, thereby has recovered former operational mode.
From above description, can find out, low-pressure ring-closing selective tripping system of the present invention, adopt low pressure cyclization to start, automatically perform the grid switching operation mode that choosing is jumped, not only avoided the generation of the voltage flicker of instantaneous power-off, the reliability of power supply and operating personnel's personal safety have also been guaranteed, the time that simultaneously makes script single supply system become double power-supply system shortens greatly, actual measurement is less than 100 milliseconds, basic suitable with the time of a circuit fast tripping protection action, can not make the malfunctioning or sensitivity of power-supply system protective device change, poor 5% of the rated voltage that is not more than of both sides supply voltage of actual measurement, the cyclization electric current of actual measurement is substantially between the 30-40% of rated current, therefore can compared with ambassador's cyclization electric current, not surpass protection definite value because both sides supply voltage is poor causes mains side protection to be moved.
The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (7)
1. a low-pressure ring-closing selective tripping system, jumps control for the choosing of three of the dual power supply system of single-trunk segmental wiring form air switches being carried out after cyclization, it is characterized in that, comprising:
The auxiliary contact of three air switches;
Relay, comprises three normally opened contacts;
Select TRIP, comprise three groups of contacts and only have one group of contact in on-state at every turn;
In described three air switches, the auxiliary contact of First air switch, second air switch and the 3rd air switch is connected in series successively, wherein the auxiliary contact of First air switch and the power firestreak of described low-pressure ring-closing selective tripping system are connected, the first end of the 3rd auxiliary contact of air switch and the coil of described relay is connected in series mutually, and the second end of the coil of described relay is connected with zero-power line;
Three normally opened contacts of described relay are connected with three input contacts in described three groups of contacts that select TRIP respectively, three output contacts in described three groups of contacts that select TRIP are connected with the switching winding of three sub-gate circuits of described three air switches respectively
Wherein, described relay is electromagnetic solenoid type structure.
2. low-pressure ring-closing selective tripping system according to claim 1, is characterized in that, between the auxiliary contact of described First air switch and described power firestreak, is also provided with fuse.
3. low-pressure ring-closing selective tripping system according to claim 1, is characterized in that, described relay also comprises the 4th normally opened contact, is connected, for sending cyclization signal with relay indicating light.
4. low-pressure ring-closing selective tripping system according to claim 3, is characterized in that, described relay is AC intermediate relay.
5. low-pressure ring-closing selective tripping system according to claim 4, is characterized in that, the rated voltage of described AC intermediate relay is AC220V.
6. low-pressure ring-closing selective tripping system according to claim 4, is characterized in that, described AC intermediate relay is the multiconductor AC intermediate relay of electromagnetic solenoid type structure.
7. according to the low-pressure ring-closing selective tripping system described in any one in claim 1 to 6, it is characterized in that, described three air switches are universal air switch.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110174401.5A CN102842951B (en) | 2011-06-24 | 2011-06-24 | Low voltage loop-closing selective-tripping system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110174401.5A CN102842951B (en) | 2011-06-24 | 2011-06-24 | Low voltage loop-closing selective-tripping system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102842951A CN102842951A (en) | 2012-12-26 |
| CN102842951B true CN102842951B (en) | 2014-12-10 |
Family
ID=47370084
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110174401.5A Active CN102842951B (en) | 2011-06-24 | 2011-06-24 | Low voltage loop-closing selective-tripping system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102842951B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2726644C1 (en) * | 2020-02-04 | 2020-07-15 | Федеральное государственное бюджетное научное учреждение "Федеральный научный агроинженерный центр ВИМ" (ФГБНУ ФНАЦ ВИМ) | Multicontact switching system having independent control of eight power contact groups connected in a mixed circuit |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104682544A (en) * | 2013-11-29 | 2015-06-03 | 国家电网公司 | Spare power automatic switching method and device |
| CN104167810A (en) * | 2014-06-13 | 2014-11-26 | 国家电网公司 | Method for verifying correctness of decoupling operation mode of expanded inner bridging line standby power automatic switching |
| CN104682551B (en) * | 2015-03-18 | 2017-01-11 | 常熟开关制造有限公司(原常熟开关厂） | Closed-loop screening method for power parallel conversion device and power parallel conversion device |
| RU2726856C1 (en) * | 2020-02-05 | 2020-07-16 | Федеральное государственное бюджетное научное учреждение "Федеральный научный агроинженерный центр ВИМ" (ФГБНУ ФНАЦ ВИМ) | Multi-contact switching system having independent control of six power contact groups connected in a mixed circuit |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101056008A (en) * | 2007-02-16 | 2007-10-17 | 江苏省电力公司常州供电公司 | Quick switching method of the transformation station power supply |
| RU2363086C1 (en) * | 2008-02-18 | 2009-07-27 | Государственное образовательное учреждение высшего профессионального образования "Уральский государственный технический университет УГТУ-УПИ" | Device for automatic switching on of section switch |
| CN201690265U (en) * | 2010-02-26 | 2010-12-29 | 南京大全电气有限公司 | PLC relay switching dual power supply |
| CN202127282U (en) * | 2011-06-24 | 2012-01-25 | 北京市电力公司 | Low-pressure ring-closing selective tripping system |
-
2011
- 2011-06-24 CN CN201110174401.5A patent/CN102842951B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101056008A (en) * | 2007-02-16 | 2007-10-17 | 江苏省电力公司常州供电公司 | Quick switching method of the transformation station power supply |
| RU2363086C1 (en) * | 2008-02-18 | 2009-07-27 | Государственное образовательное учреждение высшего профессионального образования "Уральский государственный технический университет УГТУ-УПИ" | Device for automatic switching on of section switch |
| CN201690265U (en) * | 2010-02-26 | 2010-12-29 | 南京大全电气有限公司 | PLC relay switching dual power supply |
| CN202127282U (en) * | 2011-06-24 | 2012-01-25 | 北京市电力公司 | Low-pressure ring-closing selective tripping system |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2726644C1 (en) * | 2020-02-04 | 2020-07-15 | Федеральное государственное бюджетное научное учреждение "Федеральный научный агроинженерный центр ВИМ" (ФГБНУ ФНАЦ ВИМ) | Multicontact switching system having independent control of eight power contact groups connected in a mixed circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102842951A (en) | 2012-12-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102842951B (en) | Low voltage loop-closing selective-tripping system | |
| CN107910232B (en) | A kind of Intelligent leakage protection switch | |
| CN107171431B (en) | Uninterrupted power regulating equipment, uninterrupted power regulating system and uninterrupted power regulating control method | |
| RU2568560C2 (en) | Switching device | |
| CN103630789A (en) | Auxiliary experiment device for breaker failure protection | |
| CN106291141B (en) | Automatic phase sequence identification device for three-phase power supply on construction site | |
| CN100533913C (en) | Quick switching method of the transformation station power supply | |
| CN104868584B (en) | A kind of seamless automatic switching control equipment of dc source | |
| CN105006881B (en) | One kind hauling oneself willingly into runback control system | |
| CN104715972B (en) | A kind of automatic change-over electric appliance with duplicate | |
| CN108061838A (en) | A kind of leakage tests method for ensureing user's normal electricity consumption | |
| CN202127282U (en) | Low-pressure ring-closing selective tripping system | |
| CN204732957U (en) | The seamless automatic switching control equipment of a kind of DC power supply | |
| CN202916353U (en) | Backup power auto-switching debugging circuit | |
| CN103199614A (en) | Two-way alternating current inlet wire and connection power distribution control method | |
| CN110336272A (en) | Low voltage liaison net switch-box and interconnection switch turn method of supplying power to, device | |
| CN114465209A (en) | Local feeder fault processing method and system | |
| CN203039358U (en) | An AC brake opening and closing self-holding circuit | |
| CN210724305U (en) | Fault guiding safety device, power utilization safety system, multi-path power utilization safety system and automatic bus transfer interlocking control system | |
| CN207651433U (en) | A kind of Intelligent leakage protection switch | |
| CN208001183U (en) | Backup auto-activating device and system | |
| CN202513106U (en) | Dedicated molded case circuit breaker for prepayment type electric energy meter | |
| CN2930053Y (en) | General intelligent power saving device | |
| CN211209618U (en) | Control circuit of variable frequency control cabinet of oil pumping unit | |
| CN215641683U (en) | Circuit breaker anti-tripping function testing device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| ASS | Succession or assignment of patent right |
Owner name: BEIJING ELECTRIC POWER CORP. BEIJING LUDIAN ELECTR Free format text: FORMER OWNER: BEIJING LUDIAN ELECTRIC EQUIPMENT CO., LTD. Effective date: 20121221 Owner name: STATE GRID CORPORATION OF CHINA Free format text: FORMER OWNER: BEIJING ELECTRIC POWER CORP. Effective date: 20121221 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| COR | Change of bibliographic data |
Free format text: CORRECT: ADDRESS; FROM: 100031 XICHENG, BEIJING TO: 100031 DONGCHENG, BEIJING |
|
| TA01 | Transfer of patent application right |
Effective date of registration: 20121221 Address after: 100031 West Chang'an Avenue, Beijing, No. 86 Applicant after: State Grid Corporation of China Applicant after: Beijing Electric Power Corp. Applicant after: Beijing Lead Electric Equipment Co., Ltd. Address before: 100031 Beijing Qianmen West Street, Xicheng District, No. 41 Applicant before: Beijing Electric Power Corp. Applicant before: Beijing Lead Electric Equipment Co., Ltd. |
|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |