CN108629499A - A kind of power distribution network photovoltaic plant addressing constant volume method based on second order cone theazy - Google Patents
A kind of power distribution network photovoltaic plant addressing constant volume method based on second order cone theazy Download PDFInfo
- Publication number
- CN108629499A CN108629499A CN201810381008.5A CN201810381008A CN108629499A CN 108629499 A CN108629499 A CN 108629499A CN 201810381008 A CN201810381008 A CN 201810381008A CN 108629499 A CN108629499 A CN 108629499A
- Authority
- CN
- China
- Prior art keywords
- photovoltaic plant
- distribution network
- power
- constant volume
- power distribution
- 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.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q10/00—Administration; Management
- G06Q10/04—Forecasting or optimisation specially adapted for administrative or management purposes, e.g. linear programming or "cutting stock problem"
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q10/00—Administration; Management
- G06Q10/06—Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
- G06Q10/063—Operations research, analysis or management
- G06Q10/0631—Resource planning, allocation, distributing or scheduling for enterprises or organisations
- G06Q10/06313—Resource planning in a project environment
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q50/00—Systems or methods specially adapted for specific business sectors, e.g. utilities or tourism
- G06Q50/06—Electricity, gas or water supply
Abstract
The invention discloses power distribution network photovoltaic plant addressing constant volume method of the kind based on second order cone theazy, include the following steps：The photovoltaic plant quantity of establishing power grid access is M, and the corresponding capacity of each photovoltaic plant is Cm, minimum object function is lost with distribution network line, it is in normal range (NR) with each node voltage of power distribution network, the power grid that low-voltage-grade in overload and power distribution network does not occur for each circuit of power distribution network does not occur counter send of trend to the power grid of voltage levels and establishes photovoltaic plant addressing constant volume Optimized model for constraints, it is then based on second order cone theoretical calculation photovoltaic plant addressing constant volume Optimized model, obtain the optimal addressing constant volume of power distribution network photovoltaic plant, complete the power distribution network photovoltaic plant addressing constant volume based on second order cone theazy, this method can realize the addressing constant volume of power distribution network photovoltaic plant.
Description
Technical field
The invention belongs to new-energy grid-connected planning fields, are related to a kind of power distribution network photovoltaic plant choosing based on second order cone theazy
Location constant volume method.
Background technology
Relative to fossil energy, solar energy has amount of storage huge as a kind of regenerative resource, widely distributed, uses
It is at low cost, the features such as cleanliness without any pollution, worldwide it is widely used.
The main of solar energy using form is generated electricity using solar energy, i.e. photovoltaic generation, according to photo-voltaic power generation station with
Photovoltaic generating system can be divided into photovoltaic off-grid electricity generation system (independent type photovoltaic power generation system) and photovoltaic by the relationship between power grid
Grid-connected system.The characteristics of photovoltaic off-grid electricity generation system, is not to be directly connected to power grid, and the electric energy more than needed sent out can lead to
It crosses energy storage device such as accumulator to store, when supply of electrical energy deficiency uses, and since its cost is higher, reliability is low, uses more
In the region far from public electric wire net.The characteristics of grid-connected photovoltaic system, is that it is directly connected to power grid, the electricity more than needed sent out
It can be delivered directly to power grid, in illumination deficiency, also can obtain electric energy from power grid.According to the scale and concentration of grid-connected system
Degree, and centralized photovoltaic generating system and distributed generation can be divided into.The characteristics of centralized photovoltaic generating system, is
Its design capacity is big, and access voltage class is high；The characteristics of distributing photovoltaic generating system, is that its design capacity is small, accesses voltage
Grade is low, and quantity is more but disperses very much.The access of both pv grid-connected plants can all generate power grid certain influence, photovoltaic
The random access in power station is unfavorable for the unified planning and stable operation of power grid, so there is an urgent need to the accesses to grid-connected photovoltaic power station
Problem carries out theoretical research.Now to the research method of the problem there are mainly two types of thinking, the first thinking is soft using emulating
Part such as DIgSILENT builds power distribution network simulation model, the advantage is that it can obtain every power index in detail very much, has
Conducive to analysis and research, but due to the limitation of emulation mode, optimization problem is not can solve, if by enumerating
Method finds optimal solution, and calculation amount can be very big, and can not necessarily acquire optimal solution, and second of thinking is that build power grid each
Partial mathematical model is solved using optimization algorithm, but good method can be carried specifically very much currently not yet
Go out accurate photovoltaic plant access scheme, i.e., can't realize the addressing constant volume of power distribution network photovoltaic plant.
Invention content
It is an object of the invention to overcome the above-mentioned prior art, a kind of distribution based on second order cone theazy is provided
Net photovoltaic plant addressing constant volume method, this method can realize the addressing constant volume of power distribution network photovoltaic plant.
In order to achieve the above objectives, the power distribution network photovoltaic plant addressing constant volume method of the present invention based on second order cone theazy
Include the following steps：
The photovoltaic plant quantity of establishing power grid access is M, and the corresponding capacity of each photovoltaic plant is Cm, damaged with distribution network line
Minimum object function is consumed, is in normal range (NR) with each node voltage of power distribution network, each circuit of power distribution network does not overload and matches
The power grid of low-voltage-grade does not occur counter send of trend to the power grid of voltage levels and establishes photovoltaic plant for constraints in power grid
Addressing constant volume Optimized model is then based on second order cone theoretical calculation photovoltaic plant addressing constant volume Optimized model, obtains power distribution network photovoltaic
The optimal addressing constant volume in power station completes the power distribution network photovoltaic plant addressing constant volume based on second order cone theazy.
Object function is：
Constraints is：
pGjmin≤pGj≤pGjmaxJ=1, K N (7)
vjmin≤vj≤vjmaxJ=1, K N (8)
0≤lij≤lijmaxI, j=1 ..., N (9)
Wherein, CmFor the size of m-th of photovoltaic plant capacity of access, pGjAnd qGjRespectively node j is by upper level power grid
The active power and reactive power of conveying, pDjAnd qDjThe respectively burden with power of node j and load or burden without work, pjAnd qjRespectively save
The equivalent burden with power of point j and load or burden without work, ajiFor the decision variable of photovoltaic plant access point, work as aji=1, then it represents that i-th
Photovoltaic plant accesses j-th of power transformation tiny node, works as aji=0, then it represents that i-th of photovoltaic plant does not access j-th of power transformation tiny node,
PijAnd QijThe active power and reactive power that flow to jth point by i-th point are indicated respectively；zijAnd xijThe respectively resistance of circuit ij
And reactance, lijFor circuit ij line currents square three times；vjFor square of node j voltage magnitudes, N is the sum of substation.
The invention has the advantages that：
Power distribution network photovoltaic plant addressing constant volume method of the present invention based on second order cone theazy when specific operation,
In the case of ensureing power distribution network safe operation so that minimum theoretical foundation is lost in distribution network line, is lost with distribution network line
Minimum object function, be in normal range (NR) with each node voltage of power distribution network, each circuit of power distribution network do not occur overload and distribution
In net the power grid of low-voltage-grade to the power grid of voltage levels do not occur trend it is counter send for constraints establish photovoltaic plant choosing
Location constant volume Optimized model recycles the above-mentioned Optimized model of second order cone theoretical calculation, to obtain the addressing of power distribution network photovoltaic plant
And constant volume, through emulation, there is no limit flexibility ratio is high, can directly obtain optimal result, relatively for scale of the present invention to power distribution network
In the optimization method of traditional simplified electrical network model, accuracy of the invention and reliability are more excellent.
Description of the drawings
Fig. 1 is the structure chart of 33 node 10kV distribution systems of ieee standard；
Fig. 2 is the structure chart of somewhere 35kV distribution systems.
Specific implementation mode
The present invention is described in further detail below in conjunction with the accompanying drawings：
Power distribution network photovoltaic plant addressing constant volume method of the present invention based on second order cone theazy includes the following steps：
The photovoltaic plant quantity of establishing power grid access is M, and the corresponding capacity of each photovoltaic plant is Cm, damaged with distribution network line
Minimum object function is consumed, is in normal range (NR) with each node voltage of power distribution network, each circuit of power distribution network does not overload and matches
The power grid of low-voltage-grade does not occur counter send of trend to the power grid of voltage levels and establishes photovoltaic plant for constraints in power grid
Addressing constant volume Optimized model is then based on second order cone theoretical calculation photovoltaic plant addressing constant volume Optimized model, obtains power distribution network photovoltaic
The optimal addressing constant volume in power station completes the power distribution network photovoltaic plant addressing constant volume based on second order cone theazy.
Wherein, object function is：
Wherein, constraints is：
pGjmin≤pGj≤pGjmaxJ=1, K N (7)
vjmin≤vj≤vjmaxJ=1, K N (8)
0≤lij≤lijmaxI, j=1 ..., N (9)
Wherein, CmFor the size of m-th of photovoltaic plant capacity of access, pGjAnd qGjRespectively node j is by upper level power grid
The active power and reactive power of conveying, pDjAnd qDjThe respectively burden with power of node j and load or burden without work, pjAnd qjRespectively save
The equivalent burden with power of point j and load or burden without work, ajiFor the decision variable of photovoltaic plant access point, work as aji=1, then it represents that i-th
Photovoltaic plant accesses j-th of power transformation tiny node, works as aji=0, then it represents that i-th of photovoltaic plant does not access j-th of power transformation tiny node,
PijAnd QijThe active power and reactive power that flow to jth point by i-th point are indicated respectively；zijAnd xijThe respectively resistance of circuit ij
And reactance, lijFor circuit ij line currents square three times；vjFor square of node j voltage magnitudes, N is the sum of substation.
Emulation experiment
Optimization program is write according to photovoltaic plant addressing constant volume Optimized model on optimization software cplex platforms, below will
33 node 10kV distribution systems of ieee standard and the photovoltaic plant addressing constant volume problem of somewhere 35kV distribution systems are ground
Study carefully.
33 node 10kV distribution systems structure chart of ieee standard is as shown in Figure 1, distribution network parameters are as shown in table 1, the distribution
Total burden with power of net is 3.715MW, and total load or burden without work is 2.4Mvar.Photovoltaic plant addressing constant volume Optimized model is set as：Become
The voltage in power station 1 is 10.5kV, and the active output upper limit is 6MW, lower limit 0；The voltage range of each node is 9.3kV-10.7kV；
The electric current normal upper limit of circuit isThe counter of circuit send the upper current limit to beOptimization aim is line loss
It is minimum.The quantity of access photovoltaic plant is set according to actual conditions.
Table 2 and table 3 give optimum results when 1 photovoltaic plant of access and 2 photovoltaic plants, wherein table is front-seat
The optimum results that data acquire when being given photovoltaic plant capacity, last column are while optimizing photovoltaic plant on-position and connecing
Enter the optimum results of capacity.
Somewhere 35kV distribution systems structure chart as shown in Fig. 2, the parameter of power distribution network as shown in table 4 and table 5, wherein section
Point 8 is T-type line node.Optimized model is set as：Dark colour node is 110kV substations, and the node of light colour is 35kV
Substation, using 110kV substations as voltage reference node, if the voltage magnitude of substation 1 and substation 3 is 36.75kV, voltage
Phase angle is 0, and the voltage magnitude of substation 9 and substation 12 is 36.75kV；The voltage magnitude of each node ranging from 33.25kV-
38.5kV, the sum of generating positive and negative voltage deviation are no more than the 10% of rated value；The load of each node will use minimum load as calculating
Standard；The Optimized model can constrain trend amount of the anti-send in detail, be set as not allowing to carry out tide to upper level power grid here
Stream is counter to be sent, and Line Flow positive direction is as shown in Figure 2；Optimization aim is that line loss is minimum.The quantity for accessing photovoltaic plant can root
It is set according to actual conditions.
Optimum results when 1 photovoltaic plant of access and 2 photovoltaic plants are as shown in table 6 and table 7, wherein table is front-seat
The optimum results that data acquire when being given photovoltaic plant capacity, last column are while optimizing photovoltaic plant on-position and connecing
Enter the optimum results of capacity.
Table 1
Table 2
Table 3
Table 4
Table 5
Table 6
Table 7
Claims (3)
1. a kind of power distribution network photovoltaic plant addressing constant volume method based on second order cone theazy, which is characterized in that include the following steps：
The photovoltaic plant quantity of establishing power grid access is M, and the corresponding capacity of each photovoltaic plant is Cm, most with distribution network line loss
It is small for object function, be in normal range (NR) with each node voltage of power distribution network, each circuit of power distribution network does not occur to overload and power distribution network
The power grid of middle low-voltage-grade does not occur counter send of trend to the power grid of voltage levels and establishes photovoltaic plant addressing for constraints
Constant volume Optimized model is then based on second order cone theoretical calculation photovoltaic plant addressing constant volume Optimized model, obtains power distribution network photovoltaic plant
Optimal addressing constant volume, complete the power distribution network photovoltaic plant addressing constant volume based on second order cone theazy.
2. the power distribution network photovoltaic plant addressing constant volume method according to claim 1 based on second order cone theazy, feature exist
In object function is：
3. the power distribution network photovoltaic plant addressing constant volume method according to claim 1 based on second order cone theazy, feature exist
In constraints is：
pGjmin≤pGj≤pGjmaxJ=1, K N (7)
vjmin≤vj≤vjmaxJ=1, K N (8)
0≤lij≤lijmaxI, j=1 ..., N (9)
Wherein, CmFor the size of m-th of photovoltaic plant capacity of access, pGjAnd qGjRespectively node j is conveyed by upper level power grid
Active power and reactive power, pDjAnd qDjThe respectively burden with power of node j and load or burden without work, pjAnd qjRespectively node j
Equivalent burden with power and load or burden without work, ajiFor the decision variable of photovoltaic plant access point, work as aji=1, then it represents that i-th of light
Overhead utility accesses j-th of power transformation tiny node, works as aji=0, then it represents that i-th of photovoltaic plant does not access j-th of power transformation tiny node,
PijAnd QijThe active power and reactive power that flow to jth point by i-th point are indicated respectively；zijAnd xijThe respectively resistance of circuit ij
And reactance, lijFor circuit ij line currents square three times；vjFor square of node j voltage magnitudes, N is the sum of substation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810381008.5A CN108629499A (en) | 2018-04-25 | 2018-04-25 | A kind of power distribution network photovoltaic plant addressing constant volume method based on second order cone theazy |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810381008.5A CN108629499A (en) | 2018-04-25 | 2018-04-25 | A kind of power distribution network photovoltaic plant addressing constant volume method based on second order cone theazy |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108629499A true CN108629499A (en) | 2018-10-09 |
Family
ID=63694559
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810381008.5A Pending CN108629499A (en) | 2018-04-25 | 2018-04-25 | A kind of power distribution network photovoltaic plant addressing constant volume method based on second order cone theazy |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108629499A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109782124A (en) * | 2018-12-24 | 2019-05-21 | 国网江苏省电力有限公司苏州供电分公司 | A kind of main adapted integration Fault Locating Method and system based on gradient descent algorithm |
| CN110689187A (en) * | 2019-09-23 | 2020-01-14 | 北京洛斯达数字遥感技术有限公司 | Multi-condition constraint-based automatic site selection method for transformer substation |
| CN111478321A (en) * | 2020-04-23 | 2020-07-31 | 许昌许继风电科技有限公司 | Power distribution network node selection method for connecting distributed wind power generation system |
| CN113746128A (en) * | 2020-05-27 | 2021-12-03 | 国网辽宁省电力有限公司 | Optimal distributed photovoltaic power generation planning method and device considering line loss of power distribution network |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103353979A (en) * | 2013-05-31 | 2013-10-16 | 国家电网公司 | Optimization method for locating and sizing of distributed power |
| CN103400208A (en) * | 2013-08-01 | 2013-11-20 | 天津大学 | Power distribution network distributive power supply optimal access capacity determining method based on cone optimization |
| CN104376378A (en) * | 2014-11-14 | 2015-02-25 | 浙江工商大学 | Distributed-power-source-contained power distribution network reactive power optimization method based on mixed integer cone optimization |
| CN106655177A (en) * | 2017-01-18 | 2017-05-10 | 中国南方电网有限责任公司电网技术研究中心 | Method for computing maximum access capacity of distributed power sources on basis of expansion second-order cone programming |
| CN106779313A (en) * | 2016-11-25 | 2017-05-31 | 上海电力学院 | Multiple target distributed power source addressing constant volume method based on mixed integer programming |
| CN107846040A (en) * | 2017-11-02 | 2018-03-27 | 国网重庆市电力公司电力科学研究院 | Distributed photovoltaic and energy storage coordinated planning method and system based on second order cone relaxation |
-
2018
- 2018-04-25 CN CN201810381008.5A patent/CN108629499A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103353979A (en) * | 2013-05-31 | 2013-10-16 | 国家电网公司 | Optimization method for locating and sizing of distributed power |
| CN103400208A (en) * | 2013-08-01 | 2013-11-20 | 天津大学 | Power distribution network distributive power supply optimal access capacity determining method based on cone optimization |
| CN104376378A (en) * | 2014-11-14 | 2015-02-25 | 浙江工商大学 | Distributed-power-source-contained power distribution network reactive power optimization method based on mixed integer cone optimization |
| CN106779313A (en) * | 2016-11-25 | 2017-05-31 | 上海电力学院 | Multiple target distributed power source addressing constant volume method based on mixed integer programming |
| CN106655177A (en) * | 2017-01-18 | 2017-05-10 | 中国南方电网有限责任公司电网技术研究中心 | Method for computing maximum access capacity of distributed power sources on basis of expansion second-order cone programming |
| CN107846040A (en) * | 2017-11-02 | 2018-03-27 | 国网重庆市电力公司电力科学研究院 | Distributed photovoltaic and energy storage coordinated planning method and system based on second order cone relaxation |
Non-Patent Citations (1)
| Title |
|---|
| 朱俊澎等: "考虑网络动态重构的分布式电源选址定容优化方法", 《电力系统自动化》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109782124A (en) * | 2018-12-24 | 2019-05-21 | 国网江苏省电力有限公司苏州供电分公司 | A kind of main adapted integration Fault Locating Method and system based on gradient descent algorithm |
| CN109782124B (en) * | 2018-12-24 | 2021-07-23 | 国网江苏省电力有限公司苏州供电分公司 | Main distribution integrated fault positioning method and system based on gradient descent algorithm |
| CN110689187A (en) * | 2019-09-23 | 2020-01-14 | 北京洛斯达数字遥感技术有限公司 | Multi-condition constraint-based automatic site selection method for transformer substation |
| CN110689187B (en) * | 2019-09-23 | 2023-05-23 | 北京洛斯达科技发展有限公司 | Automatic site selection method for transformer substation based on multi-condition constraint |
| CN111478321A (en) * | 2020-04-23 | 2020-07-31 | 许昌许继风电科技有限公司 | Power distribution network node selection method for connecting distributed wind power generation system |
| CN113746128A (en) * | 2020-05-27 | 2021-12-03 | 国网辽宁省电力有限公司 | Optimal distributed photovoltaic power generation planning method and device considering line loss of power distribution network |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103353979B (en) | The Optimizing Site Selection of a kind of distributed power source and constant volume method | |
| CN104578157B (en) | Load flow calculation method of distributed power supply connection power grid | |
| CN108629499A (en) | A kind of power distribution network photovoltaic plant addressing constant volume method based on second order cone theazy | |
| WO2017067120A1 (en) | Method for acquiring low-voltage ride-through data of photovoltaic power station | |
| CN112653154B (en) | Distributed photovoltaic power distribution network reactive power optimization control method based on edge calculation | |
| CN101882785B (en) | Flow analysis system and method for intelligent power distribution networks containing distributed generation | |
| CN105375513A (en) | Automatic 110kV wind power field voltage control method based on real-time online equivalence | |
| CN110912177A (en) | Multi-objective optimization design method for multi-terminal flexible direct current power transmission system | |
| CN107332252A (en) | A kind of power distribution network low-voltage comprehensive processing method of meter and broad sense reactive source | |
| CN202651806U (en) | Smooth wind-power photovoltaic power generation control system of battery energy storage station | |
| CN104362650A (en) | Electric power system reactive power optimization method considering cost factor | |
| Parija et al. | Power quality improvement in hybrid power system using D-STATCOM | |
| CN111478335B (en) | Power distribution network load flow calculation method and system considering distributed photovoltaic | |
| Lei et al. | Modeling and analysis of MW-level grid-connected PV plant | |
| CN110323779B (en) | Method and system for dynamically aggregating power of distributed power generation and energy storage device | |
| Capasso et al. | Power architectures for the integration of photovoltaic generation systems in DC-microgrids | |
| CN110380419A (en) | It is a kind of to mix random and interval variable uncertain tidal current computing method | |
| CN101154828A (en) | Networking intermittent renewable power supply network-merging equipment | |
| Matsuo et al. | Grid-connected electric-power control algorithm for promoting the introduction of renewable energy | |
| CN201075701Y (en) | Renewable energy source parallel in power generation system | |
| Ethmane et al. | Transient stability enhancement of statcom integration in power grid | |
| Lu et al. | Impact of series compensation on operation performance of large‐scale PV plants | |
| CN107562971B (en) | Alternating current/direct current power grid power flow calculation method based on PSS/E | |
| CN106410867B (en) | A kind of electric energy router power flow method for optimization analysis | |
| CN206211549U (en) | A kind of collecting and distributing type photovoltaic power generation control system based on micro-capacitance sensor technology |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20181009 |
|
| RJ01 | Rejection of invention patent application after publication |