CN2544452Y - Low-voltage idle dynamic compensator - Google Patents
Low-voltage idle dynamic compensator Download PDFInfo
- Publication number
- CN2544452Y CN2544452Y CN 02239201 CN02239201U CN2544452Y CN 2544452 Y CN2544452 Y CN 2544452Y CN 02239201 CN02239201 CN 02239201 CN 02239201 U CN02239201 U CN 02239201U CN 2544452 Y CN2544452 Y CN 2544452Y
- Authority
- CN
- China
- Prior art keywords
- optocoupler
- thyristor
- reactive power
- triggering
- compensation device
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Control Of Electrical Variables (AREA)
Abstract
The utility model relates to a low-voltage reactive dynamic compensator. The inner of the box is provided with a microcomputer reactive compensation controller, a triggering device, an air switch, and a sampling current transformer. The utility model is characterized in that: a main circuit of the compensation device is controlled by three phases and two valves, that is to say, only two phases on each capacitor bank are connected with a half-control valve consisting of a thyristor and a diode, and one phase is through. The capacitor bank is formed by three capacitors according to a triangle connection method. The triggering device uses an active advance triggering circuit which sends out a triggering pulse when the voltage of two ends of the thyristor are approximately equal and connects the thyristor when the thyristor just overcomes a dead zone and the voltage is in a forward bias. Each half-control valve is connected with the capacitor bank through a reactance, and a pre-charge circuit is arranged in the main circuit. The two ends of the thyristor of the main circuit are parallel provided with an RC suction network and a varistor. The device does not need to keep constant temperature; the working temperature under natural cooling conditions is low, and a mistaken triggering does not damage the device at any time. Therefore, the utility model has the advantages of high reliability, low manufacturing cost, and easy popularization and application.
Description
Affiliated technical field
The utility model relates to a kind of low-voltage reactive compensator capable, refers in particular to a kind of low voltage reactive power dynamic compensation device.
Background technology
Most power consumers have all been installed low-voltage reactive compensator capable.Reactive power compensation has improved the power factor (PF) of user power utilization, prevents that a large amount of reactive powers from transmitting at a distance.It can reduce the loss of circuit, reduces voltage drop, and power supply quality is improved, and also can make transformer increase effective output capacity.Traditional low-voltage reactive compensator capable is realized by the mechanical switch switching capacitance, can produce in the switching and shove and overvoltage, makes switch produce spark and noise, and the device operational reliability is poor, and useful life is short.These traditional low-voltage reactive compensator capables can not be worked under the environment that the dust dirt is arranged, and outdoor use is also fragile, can not play compensating action for quick variation and impact load.With this contactless electronic beam switch switched capacitor of thyristor valve, be called Reactive Compensation Device, it can solve above all problems.But there is following subject matter in the product of operation at present: the one, and fan all is equipped with in temperature rise during the alternating-current switch operation basically, what have has also adorned insulating box, even is added with overtemperature function out of service, and so not only cost increases, power consumption also increases, and operational reliability reduces; As: " fully automatic contactless throw-in and throw-off reactive compensator " (ZL00201115.8), one of its characteristics have the idle supervising device of microcomputer etc. exactly in the temperature control casing; The 2nd, on useful life, do not surpass traditional product, when strong jamming or circuit generation fault, damage easily; The 3rd, the product cost height, price is difficult to be accepted by the user, also just can't apply.
Summary of the invention
The purpose of this utility model is to solve the problems referred to above of prior art existence and a kind of low voltage reactive power dynamic compensation device is provided, and it need not constant temperature, and the temperature rise of working under the condition of natural cooling is low, false triggering at any time can not damage yet, the reliability height, low cost of manufacture is applied easily.
For achieving the above object, the solution that the utility model is taked is: a kind of low voltage reactive power dynamic compensation device, microcomputer reactive power compensation controller is arranged in the casing, trigger instrument, air switch, sampled current transformer, the main circuit that it is characterized in that compensation arrangement adopts the control of three-phase two valves, be to have only two to be connected to by a thyristor and the half control valve that diode is formed on every group of capacitance group, one leads directly to mutually.
Described capacitance group is made up of by delta connection three electric capacity.
Described triggering instrument adopts the leading circuits for triggering of active formula, and the leading circuits for triggering of this active formula send trigger impulse when thyristor both end voltage approximately equal, has just overcome at thyristor to make its conducting when dead band voltage is in forward bias.
Described every half control valve is received capacitance group by reactance.
In the described main circuit pre-charge circuit is set.
Described main circuit thyristor two ends also and have RC to absorb network and piezo-resistance.
Because main circuit adopts the simplest three-phase two valves control, used like this element is minimum, controls also the simplest, the electric capacity that adds use is cheapest 380V delta connection electric capacity, it is minimum that cost is dropped to, and price can be accepted by users, helps applying.
Adopt active leading circuits for triggering owing to trigger instrument, the temperature rise when making the thyristor operation drops to minimum, without insulating box, also without the fan heat radiation, more need not to be provided with the overtemperature exit function.
Because every half control valve is received capacitance group by reactance, and this reactance at first guarantees the brilliant lock of false triggering at any time this can not damage, secondly the current-rising-rate in the time of can also reducing the thyristor conducting widely, discharging current when being reduced in the electric capacity input between each group also has inhibitory action to high order harmonic component once more.The place more serious to high order harmonic component can normally move electric capacity according to the situation configuration reactance of minimum subharmonic under the harmonic wave serious environmental.The inductance value of this reactance also should quite keep constant under the range frequencies.
Owing to be provided with pre-charge circuit, no matter be that power supply closes or send a telegram here suddenly in the back that cuts off the power supply, main circuit all can treat that equipment begins operate as normal near disconnecting behind the peak value by this circuit with very little current charges.Because main circuit thyristor two ends also and have RC to absorb network and piezo-resistance, the protection thyristor is not subjected to superpotential damage.Owing to take these measures, guaranteed compensation arrangement freedom from repairs for a long time.
The main circuit of two half control valve controls of three-phase adds pre-charge circuit, the group number and the capacitance of electric capacity input can be increased widely, the compensation arrangement capacity can reach hundreds of kilovars, and switching group number has enlarged the scope of application of product on the capacitance compensation screen of 10-12 level.Also can make traditional product be transformed into the reactive-load dynamic compensation product and become very easy, except that controller, mechanical fling-cut switch, other all can keep in the traditional product, and required expense is very low.
Description of drawings
Below in conjunction with embodiment and accompanying drawing thereof the good effect of the utility model and generation thereof is remake description.
Accompanying drawing 1 is the circuit diagram (only drawn here two groups, group number and capacity should be unrestricted, only need to increase to trigger to get final product) of present embodiment.
Accompanying drawing 2 is sample circuit figure.
Accompanying drawing 3 triggers the wiring schematic diagram of instrument KYCC.
Accompanying drawing 4 is microcomputer reactive power compensation controller JK wiring schematic diagrams.
Accompanying drawing 5 is connection diagrams of time relay KT and auxiliary relay KA.
Accompanying drawing 6 is to trigger instrument KYCC electrical schematic diagram (phase of only drawing, every phase all is identical) here.
Embodiment
As Fig. 1-shown in Figure 6, a kind of low voltage reactive power dynamic compensation device, microcomputer reactive power compensation controller JK is arranged in the casing, trigger instrument KYCC, air switch QF, sampled current transformer TA, the main circuit that it is characterized in that compensation arrangement adopts the control of three-phase two valves, be to have only two to be connected to the half control valve of being made up of a thyristor V1 or V2 or V3 or V4 and diode V5 or V6 or V7 or V8 on every group of capacitance group C1 or the C2, one leads directly to mutually.
As shown in Figure 1, described capacitance group C1 or C2 are made up of by delta connection three electric capacity.
See Fig. 3 and Fig. 6, described triggering instrument KYCC adopts the leading circuits for triggering of active formula, the leading circuits for triggering of this active formula send trigger impulse when thyristor V1 or V2 or V3 or V4 both end voltage approximately equal, just overcome at thyristor V1 or V2 or V3 or V4 to make its conducting when dead band voltage is in forward bias.
As shown in Figure 1, described every half control valve is received capacitance group C1 or C2 by reactance L1 or L2 or L3 or L4.
See Fig. 1 and Fig. 5, in the described main circuit pre-charge circuit is set.Thyristor V1 or V2 or V3 or 4 forwards connect, diode V5 or V6 or V7 or V8 polarity are in contrast, the circuit that is made of resistance R and auxiliary relay KA normally opened contact of having connected in their lower end, this circuit constitutes described pre-charge circuit with time relay KT, auxiliary relay KA.
As shown in Figure 1, described main circuit thyristor V1 or V2 or V3 or V4 two ends are also and have RC to absorb network and piezo-resistance Ru.
As shown in Figure 1, power end is connected to three lightning arrester FV1, FV2, FV3, and they are used to absorb atmospheric over-voltage and switching overvoltage.Air switch QF is as total mains switch, and it has connected identical capacitor group C1, C2, and the electric capacity among capacitor group C1 or the C2 is to receive air switch one phase after the parallel connection.
See Fig. 4, microcomputer reactive power compensation controller JK detects the reactive current in the load current, sends the input signal when needs compensate, and this blackout during the electric capacity excision makes compensation back power factor (PF) reach user's requirement.This controller power factor (PF) can preset by customer requirements, is up to 0.99, and numeral shows; it also has time-delay between overvoltage protection, group, and overpressure value can be adjusted between 400V-440V, and delay time also can be adjusted between 0.1s-60s; adjusted value is presented on the display screen, and is very convenient.It also has automatically-manual operation function, and the 2KV that controller can also be resisted power end input disturbs and can misoperation.
As shown in Figure 2, sampled current transformer TA flows through by the electric current of compensating load, and its voltage sampling is connected to power supply from power supply by a pair of delayed contact of time relay KT, and the controller of microcomputer reactive power compensation just JK starts working after precharge is finished.
See Fig. 1, Fig. 3 and Fig. 6, trigger the conducting of instrument KYCC control thyristor V1 or V2 or V3 or V4.Trigger instrument KYCC and adopt the leading circuits for triggering of active formula, in this circuit, send trigger impulse to thyristor V1 or V2 or V3 or V3 or V3 control utmost point G1 or G2 or G3 or G4 during triode BG conducting, the condition of triode BG conducting is optocoupler IC5 conducting, + 7V power supply passes through resistance R 7 to triode BG base stage input current, optocoupler IC5, optocoupler IC4, optocoupler IC3 series connection, the condition of optocoupler IC5 conducting is optocoupler IC4, all conductings of optocoupler IC3, + 9V power supply is by optocoupler IC4, optocoupler IC5, optocoupler IC3, resistance R 4 arrival-9V power supplys, and the turn-on condition of optocoupler IC4 is K
+, direct current output arranged between Ko.This is provided by microcomputer reactive power compensation controller JK, as long as the instruction of input is arranged, optocoupler IC4 will conducting.And the forward voltage drop of optocoupler IC3 turn-on condition to be capacitance group C1 or C2 go up operating voltage that the current potential absolute value must be higher than voltage-stabiliser tube DW adds diode D1.Because in this circuit, we do not wish at the positive half cycle of power supply trigger impulse is arranged, and are exactly at negative half period, also wish trigger impulse only appear at thyristor V1 or V2 or V3 or V4 current over-zero near.It is that optocoupler IC2 must end that triode BG conducting also has a condition, in case its conducting, 4 times terminal potentials of resistance R will be by clamp to the+9V, and optocoupler IC5 can not conducting.And the condition that optocoupler IC2 ends is thyristor V1 or V2 or V3 or V4 two terminal potential approximately equals, resistance R 1, R2 series connection are on thyristor V1 or V2 or V3 or V4 ends A 1, A2, when thyristor V1 or V2 or V3 or V4 ends A 1, A2 current potential when equating, optocoupler IC1 is output as zero, the output of rectifier bridge BJ direct current also is zero, and optocoupler IC2 ends.This shows, it is that microcomputer reactive power compensation controller JK has output (input signal) that thyristor V1 or V2 or V3 or V4 control utmost point G1 or G2 or G3 or G4 have the condition of trigger impulse, thyristor V1 or V2 or V3 or V4 both end voltage approximately equal (being about 2V-3V) by resistance R 2 adjustings, capacitance group C1 or C2 are filled with certain electric charge, and three conditions are indispensable.Certainly wanting conducting also must be thyristor V1 or V2 or V3 or V4 forward bias.
See Fig. 6, the leading circuits for triggering course of work of active formula is such: in wait state, diode V5 or V6 or V7 or V8 charge to negative peak, if microcomputer reactive power compensation controller JK sends the input signal, then satisfied optocoupler IC4 turn-on condition, optocoupler IC3 turn-on condition this moment also satisfies, as long as supply voltage is near near the negative peak, optocoupler IC2 will end, at this moment trigger impulse output just arranged, will conducting as long as thyristor V1 or V2 or V3 or V4 are in forward bias, capacitance group C1 or C2 are dropped into.Through half period, thyristor V1 or V2 or V3 or V4 will turn-off when current over-zero naturally; Following half period, because of diode V5 or V6 or V7 or V8 are in forward bias, it will keep conducting.This process is gone round and begun again, and is exactly complete sine-wave current on capacitance group C1, C2.Why it is called the leading circuits for triggering of active formula, be at every turn in diode V5 or V6 or V7 or V8 charging process when electric charge reaches certain potentials, just begin to have trigger impulse, but this moment, diode V5 or V6 or V7 or V8 were still in charging, and its two terminal potential makes thyristor V1 or V2 or V3 or V4 be in reverse bias.Have only diode V5 or V6 or V7 or V8 charging to finish, power supply makes thyristor V1 or V2 or V3 or V4 overcome the dead band and presses and be in forward bias, thyristor V1 or V2 or V3 or V4 conducting at once.This circuit has guaranteed that the moment of thyristor V1 or V2 or V3 or the each conducting of V4 all is in forward bias, and two terminal potentials are equal substantially, so temperature rise is minimum.
See Fig. 1-Fig. 6, the operation principle of present embodiment is: air switch QF closes, and when power supply, time relay KT starts working, and at the negative half period of power supply, resistance R is charged to capacitance group C1, C2 by diode V5 or V6 or V7 or V8.This electric current is very little, only is tens of milliamperes, can not impact to circuit and microcomputer reactive power compensation controller JK, triggering instrument KYCC.To be charged to peak value, the delayed contact work of time relay KT, it makes microcomputer reactive power compensation controller JK enter operating state on the one hand, make auxiliary relay KA get electric work on the other hand, auxiliary relay KA normally opened contact closure is with each resistance R short circuit, and thyristor V1 or V2 or V3 or V4 and diode V5 or V6 or V7 or V8 have become direct inverse parallel.Then diode V5 or V6 or V7 or V8 charged to negative peak and were in wait state if microcomputer reactive power compensation controller JK does not send the input signal this moment; This moment is if microcomputer reactive power compensation controller JK sends the input signal, supply voltage near negative peak near, trigger instrument KYCC and can send the triggering and conducting signal to thyristor V1 or V2 or V3 or V4 trigger electrode G1 or G2 or G3 or G4, treat that power supply makes thyristor V1 or V2 or V3 or V4 overcome dead band voltage and when being in forward bias, thyristor V1 or V2 or V3 or V4 conducting immediately, capacitance group C1, C2 drop into.Naturally close when current conducting is maintained to thyristor V1 or V2 or V3 or V4 current over-zero, and diode V5 or V6 or V7 or V8 are in forward conduction during the power-half cycle, this just drops into capacitance group C1, C2.Then do not have trigger impulse if microcomputer reactive power compensation controller JK drops into blackout, thyristor V1 or V2 or V3 or V4 turn-off when current over-zero naturally, and capacitance group C1, C2 deactivate.
Claims (10)
1, a kind of low voltage reactive power dynamic compensation device, microcomputer reactive power compensation controller is arranged in the casing, trigger instrument, air switch, sampled current transformer, it is characterized in that: the main circuit of compensation arrangement adopts the control of three-phase two valves, be to have only two to be connected to by a thyristor and the half control valve that diode is formed on every group of capacitance group, one leads directly to mutually.
2, a kind of low voltage reactive power dynamic compensation device according to claim 1, it is characterized in that: described capacitance group is made up of by delta connection three electric capacity.
3, a kind of low voltage reactive power dynamic compensation device according to claim 1, it is characterized in that: described triggering instrument adopts the leading circuits for triggering of active formula, the leading circuits for triggering of this active formula send trigger impulse when thyristor both end voltage approximately equal, just overcome at thyristor to make its conducting when dead band voltage is in forward bias.
4, a kind of low voltage reactive power dynamic compensation device according to claim 1 is characterized in that: described every half control valve is received capacitance group by reactance.
5, a kind of low voltage reactive power dynamic compensation device according to claim 1 is characterized in that: in the described main circuit pre-charge circuit is set.
6, a kind of low voltage reactive power dynamic compensation device according to claim 1 is characterized in that: described main circuit thyristor two ends also and have RC to absorb network and piezo-resistance.
7, a kind of low voltage reactive power dynamic compensation device according to claim 5 is characterized in that: the circuit that is made of resistance R and auxiliary relay KA normally opened contact constitutes described pre-charge circuit with time relay KT, auxiliary relay KA.
8, a kind of low voltage reactive power dynamic compensation device according to claim 1, it is characterized in that: the main circuit power termination has three lightning arrester FV1, FV2, FV3; Air switch QF is as total mains switch, and it has connected identical capacitor group, and the electric capacity in the capacitor group is to receive air switch QF one phase after the parallel connection.
9, a kind of low voltage reactive power dynamic compensation device according to claim 1, it is characterized in that: sampled current transformer flows through by the electric current of compensating load, and its voltage sampling is connected to power supply from power supply by a pair of delayed contact of time relay KT.
10, a kind of low voltage reactive power dynamic compensation device according to claim 3, it is characterized in that: in the leading circuits for triggering of active formula, send trigger impulse to the thyristor control utmost point during triode BG conducting, the condition of triode BG conducting is optocoupler IC5 conducting, + 7V power supply passes through resistance R 7 to triode BG base stage input current, optocoupler IC5, optocoupler IC4, optocoupler IC3 series connection, the condition of optocoupler IC5 conducting is optocoupler IC4, all conductings of optocoupler IC3, + 9V power supply is by optocoupler IC4, optocoupler IC5, optocoupler IC3, resistance R 4 arrival-9V power supplys, the turn-on condition of optocoupler IC4 is K
+, direct current output arranged between Ko, optocoupler IC3 turn-on condition is the forward voltage drop that operating voltage that capacitance group current potential absolute value must be higher than voltage-stabiliser tube DW adds diode D1, it is that optocoupler IC2 must end that triode BG conducting also has a condition, the condition that optocoupler IC2 ends is thyristor two terminal potential approximately equals, resistance R 1, R2 series connection on the thyristor two ends, when thyristor two terminal potentials when equating, optocoupler IC1 is output as zero, the output of rectifier bridge BJ direct current also is zero, and optocoupler IC2 ends.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02239201 CN2544452Y (en) | 2002-06-15 | 2002-06-15 | Low-voltage idle dynamic compensator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02239201 CN2544452Y (en) | 2002-06-15 | 2002-06-15 | Low-voltage idle dynamic compensator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2544452Y true CN2544452Y (en) | 2003-04-09 |
Family
ID=33712663
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 02239201 Expired - Fee Related CN2544452Y (en) | 2002-06-15 | 2002-06-15 | Low-voltage idle dynamic compensator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2544452Y (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102110985A (en) * | 2011-03-05 | 2011-06-29 | 中国船舶重工集团公司第七一二研究所 | Reactive power compensation device for thyristor cyclically-switched capacitor |
| CN102510067A (en) * | 2011-11-02 | 2012-06-20 | 西安交通大学 | Method for preventing thyristors from being locked during quick and repeated zero cross switching of three-phase thyristor switched capacitor (TSC) |
| CN102946106A (en) * | 2012-11-27 | 2013-02-27 | 常州市宏大电气有限公司 | Silicon controlled rectifier combination switch |
| CN102946108A (en) * | 2012-11-21 | 2013-02-27 | 保定供电公司 | Voltage automatic compensation device |
| CN103606923A (en) * | 2013-11-11 | 2014-02-26 | 董先庆 | Intermediate frequency furnace harmonic wave treatment and reactive power compensation apparatus |
-
2002
- 2002-06-15 CN CN 02239201 patent/CN2544452Y/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102110985A (en) * | 2011-03-05 | 2011-06-29 | 中国船舶重工集团公司第七一二研究所 | Reactive power compensation device for thyristor cyclically-switched capacitor |
| CN102510067A (en) * | 2011-11-02 | 2012-06-20 | 西安交通大学 | Method for preventing thyristors from being locked during quick and repeated zero cross switching of three-phase thyristor switched capacitor (TSC) |
| CN102510067B (en) * | 2011-11-02 | 2014-03-12 | 西安交通大学 | Method for preventing thyristors from being locked during quick and repeated zero cross switching of three-phase thyristor switched capacitor (TSC) |
| CN102946108A (en) * | 2012-11-21 | 2013-02-27 | 保定供电公司 | Voltage automatic compensation device |
| CN102946106A (en) * | 2012-11-27 | 2013-02-27 | 常州市宏大电气有限公司 | Silicon controlled rectifier combination switch |
| CN102946106B (en) * | 2012-11-27 | 2015-04-08 | 常州市宏大电气有限公司 | Silicon controlled rectifier combination switch |
| CN103606923A (en) * | 2013-11-11 | 2014-02-26 | 董先庆 | Intermediate frequency furnace harmonic wave treatment and reactive power compensation apparatus |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20120187089A1 (en) | High-voltage, super-voltage and heavy current breaker | |
| CN102931669B (en) | Based on the device of Synchronous Pre charge switch opening-closing capacitor bank | |
| CN2544452Y (en) | Low-voltage idle dynamic compensator | |
| CN103606933A (en) | Reactive capacitor compensation cabinet | |
| CN211627718U (en) | Multifunctional large-current impact electromagnetic compatibility testing equipment | |
| CN2596644Y (en) | IGBT over current protective circuit | |
| CN1845456A (en) | Series type composite switch circuit of switched capacitor bank | |
| CN201286085Y (en) | SCR self power supply gate triggering board | |
| CN103954810A (en) | 10/700 muS impulse voltage generator | |
| CN2907028Y (en) | Serial-type combined switch circuit for capacitor bank switching | |
| CN208890368U (en) | A kind of substation's overvoltage protection circuit | |
| CN203553955U (en) | Reactive capacitance compensation cabinet | |
| CN2674738Y (en) | Fault current limiter | |
| CN216252192U (en) | Comprehensive protection device for switching transient impact suppression of medium-voltage parallel capacitor | |
| CN2882075Y (en) | Zero cross trigger high voltage dynamic reactive power compensation device | |
| CN2471005Y (en) | High-voltage prize-type power-free compensation device | |
| CN201118240Y (en) | Wind power generation high voltage dynamic filtering compensation apparatus | |
| CN203205878U (en) | Device based on capacitor group switching performed by synchronous pre-charging switches | |
| CN2471006Y (en) | Outdoor compound powerfree compensation device | |
| CN2691138Y (en) | Secondary swithch type 6KV and 10KV static reactive compensator | |
| CN2549635Y (en) | Multifunctional safety device of electrical apparatus | |
| CN218124363U (en) | Charging and discharging circuit, energy router and consumer | |
| CN218243018U (en) | Novel fast saturated damper and capacitive voltage transformer in CVT of intelligent substation | |
| CN202435049U (en) | Novel high-voltage series voltage compensation device | |
| CN213661482U (en) | High-voltage solid soft starting device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |