CN103124063B - Arrester overvoltage protection device with variable voltage ratio and implementation method - Google Patents
Arrester overvoltage protection device with variable voltage ratio and implementation method Download PDFInfo
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- CN103124063B CN103124063B CN201210267156.7A CN201210267156A CN103124063B CN 103124063 B CN103124063 B CN 103124063B CN 201210267156 A CN201210267156 A CN 201210267156A CN 103124063 B CN103124063 B CN 103124063B
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- lightning arrester
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- thyristor
- detection system
- arrester
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- 238000000034 method Methods 0.000 title claims abstract description 13
- 238000001514 detection method Methods 0.000 claims abstract description 38
- 229910044991 metal oxide Inorganic materials 0.000 claims description 5
- 150000004706 metal oxides Chemical group 0.000 claims description 5
- 238000012544 monitoring process Methods 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 18
- 239000011787 zinc oxide Substances 0.000 description 9
- 230000008901 benefit Effects 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 4
- 230000001681 protective effect Effects 0.000 description 3
- 230000000630 rising effect Effects 0.000 description 2
- 230000001052 transient effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
Abstract
The invention provides an arrester overvoltage protection device with a variable voltage ratio and an implementation method, belonging to the technical field of power electronics. The device comprises an arrester serial connection group, a thyristor system and a fault detection system; the thyristor system is connected in parallel with an arrester in the arrester serial connection group; and the fault detection system is connected in parallel with the arrester serial connection group. The arrester overvoltage protection device with the variable voltage ratio has a relatively small number of used parts, a simple structure and a small floor area. In addition, as the power electronic devices used by the device are low in cost, the arrester overvoltage protection device with the variable voltage ratio lowers comprehensive manufacturing cost of a whole set of device, gives a consideration to economical efficiency and practical applicability, and has relatively good application foreground.
Description
Technical field
The invention belongs to electric and electronic technical field, be specifically related to the variable lightning arrester over-pressure safety device of a kind of pressure ratio and implementation method.
Background technology
Overvoltage refers to due to internal fault, switching manipulation or is struck by lightning, and causes the instantaneous or long-term voltage rising that also electric device may be caused to damage higher than the specified permission voltage of electrical network.Restriction transmission system overvoltage is for reduction project cost and ensure that system safety stable operation is significant.In circuit on power system, restriction Frequency Transient Overvoltage, all types of switching overvoltages need be carried out and (comprise circuit and transformer station's closing overvoltage, circuit single-phase reclose overvoltage, line-to-ground fault occurs and eliminates overvoltage and off-the-line overvoltage), the research of the measure such as system thunder defending, recovery voltage.In the occasion that some precision equipments run, if there is overvoltage fault, not only possibility damage equipment, makes equipment ineffective treatment, also can produce a very large impact simultaneously to system line, bring serious loss.For proterctive equipment normally runs, need the overvoltage of limiting device.Current overvoltage protection device mainly adopts metal oxide to cross depressor and zinc oxide arrester.
Metal oxide arrester (zinc oxide arrester) develops from valve type arrester; it is the lightning arrester of current performance the best; because of the nonlinear characteristic that it is good, both can be used as the lightning protection device of power transmission line, transformer station, also can be used as the protective device of line over-voltage.Residual voltage under zinc oxide arrester nominal current and the ratio of nominal voltage are pressure ratio.For transmission line, pressure ratio ratio is less in theory, then lightning arrester is non-linear better, and protective value is better.Pressure ratio depends on the manufacturing level of lightning arrester, and zinc oxide arrester internal structure main body is the piezo-resistance of multicolumn parallel connection, can reduce pressure ratio, but corresponding technological level requires by increasing parallel column number or increasing resistor disc diameter high, expensive.
Zinc oxide arrester internal structure main body is the piezo-resistance of multicolumn parallel connection, be that material of main part is made with zinc oxide, its voltage nonlinearity is high, capacity is large, residual voltage is low, leakage current is little, without afterflow, voltage-current characteristic is symmetrical, voltage range is wide, fast response time, voltage temperature coefficient are little, and has the advantages such as technique is simple, with low cost.In the voltage-current characteristic of zinc oxide resistance sheet, when magnitude of voltage is lower than puncture voltage, resistor disc is close to insulator, the electric current flow through is very little, when applied voltage is higher than puncture voltage, the electric current flowing through resistor disc sharply increases with the increase of voltage, even reaches the increase of several order of magnitude, shows very strong non-linear relation.When flowing through current density > 10
3a/cm
2time, voltage-current characteristic reaches big current rising area.Adopt during zinc oxide arrester overvoltage and mainly apply its good nonlinear characteristic.When there is overvoltage fault, the lightning arrester in parallel with equipment effectively can absorb big current, and the equipment voltage of making remains on certain value, avoids overvoltage and the rush of current of equipment.
The key property characterizing zinc oxide arrester has: allow the highest power frequency voltage effective value be applied between lightning arrester two ends to be rated voltage, determined by system transient modelling overvoltage; The highest power frequency voltage effective value be applied to lastingly between lightning arrester two ends is allowed to be continuous operating voltage; Residual voltage under nominal current and the ratio of nominal voltage are pressure ratio; The maximum of the highest power-frequency voltage be applied to lastingly between lightning arrester two ends is allowed to be chargeability to the ratio of power frequency reference voltage; Discharging current is residual voltage by the maximum voltage value at its two ends during lightning arrester.These parameters are all lightning arrester regulations when dispatching from the factory, and such as residual voltage test can only simulate reference value when every sheet piezoresistive wafer leads to nominal impulse electric current.Adopt the lightning arrester that rated voltage is higher to be used as overvoltage protection, while adding continuous operating voltage, residual voltage also correspondingly increases, and may impact the equipment that need protect.Take into full account with system insulation mated condition after, the protective value of the lower lightning arrester of pressure ratio is better.
In the control of transmission line of alternation current, compare with the lightning arrester bypass mode such as mechanical switch and relay, anti-parallel thyristor has the advantages such as response is fast, easy to control, and positive and negative pulse all can triggering and conducting, and thus its control circuit is fairly simple.The rated current of current thyristor can reach kiloampere, has good registration property with lightning arrester.
Summary of the invention
In order to overcome above-mentioned the deficiencies in the prior art; the invention provides the variable lightning arrester over-pressure safety device of a kind of pressure ratio and implementation method; use parts are less; structure is simple, and floor space is little, in addition; device power electronic device cost used is low; reduce the comprehensive cost of the complete sets of equipment, take into account economy and practicality, there is good application prospect.
In order to realize foregoing invention object, the present invention takes following technical scheme:
The lightning arrester over-pressure safety device that pressure ratio is variable, described device comprises lightning arrester series connection group, thyristor system and fault detection system; Connect with described lightning arrester lightning arrester in group of described thyristor system is in parallel, and described fault detection system is connected with described lightning arrester group parallel connection.
Described thyristor system comprises at least one anti-parallel thyristor and circuits for triggering thereof, and described circuits for triggering are in parallel with fault detection system.
Described lightning arrester series connection group is composed in series successively by two or more lightning arresters, and a lightning arrester anti-parallel thyristor in parallel, described lightning arrester series connection group is in parallel with protected equipment.
Described fault detection system comprises overvoltage detection system and over-current detection system; overvoltage detection system group of connecting with described protected equipment and described lightning arrester is all in parallel, and the over-current detection system lightning arrester of anti-parallel thyristor not in parallel in group of connecting with described lightning arrester is connected.
Described anti-parallel thyristor is inverse parallel gate level turn-off thyristor.
Described lightning arrester is metal oxide arrester.
The voltage magnitude at the protected equipment two ends of described fault detection system on-line monitoring and the current amplitude of lightning arrester branch road, if voltage magnitude exceedes definite value V1 or current amplitude when exceeding definite value A1, described fault detection system judges that overvoltage fault appears in protected equipment, described circuits for triggering send triggering signal to anti-parallel thyristor gate pole, control anti-parallel thyristor conducting, the lightning arrester that temporary short circuit is in parallel with anti-parallel thyristor; During the overvoltage failture evacuation of protected equipment; fault detection system detects the current amplitude flowing through the lightning arrester of anti-parallel thyristor not in parallel; if flow through the current amplitude of the lightning arrester of anti-parallel thyristor not in parallel lower than definite value A2; described circuits for triggering stop sending triggering signal; during voltage zero-cross, anti-parallel thyristor disconnects, and the lightning arrester of short circuit puts into operation again.
The lightning arrester overvoltage protection implementation method that pressure ratio is variable, said method comprising the steps of:
Step 1: carry out On-line Fault Detection;
Step 2: Logic judgment, if the voltage magnitude at protected equipment two ends is less than definite value V1 and the current amplitude of lightning arrester branch road is less than definite value A1, then returns step 1 and continues to perform; If the current amplitude that the voltage magnitude at protected equipment two ends rises to definite value V1 or lightning arrester branch road is greater than definite value A1, then perform step 3;
Step 3: circuits for triggering send triggering signal to anti-parallel thyristor gate pole, make anti-parallel thyristor conducting, the lightning arrester that short circuit is in parallel with it;
Step 4: the electric current on-line checkingi carrying out lightning arrester branch road;
Step 5: Logic judgment, if the current amplitude flowing through lightning arrester not in parallel with anti-parallel thyristor is not less than A2, then returns step 4 and continues to perform; If the current amplitude flowing through lightning arrester not in parallel with anti-parallel thyristor is less than A2, then circuits for triggering stop sending triggering signal, and anti-parallel thyristor disconnects, and the lightning arrester of short circuit accesses lightning arrester series connection group again, returns step 1.
Compared with prior art, beneficial effect of the present invention is:
1. use parts less, structure is simple, and floor space is little;
2. the power electronic device cost that device is used is low, reduces the comprehensive cost of the complete sets of equipment, takes into account economy and practicality, have good application prospect;
3. residual voltage of arrester when limiting fault, can reduce pressure ratio, improve the level of protection of lightning arrester, improve system reliability, can directly apply to known excess voltage protection, will bring very large economic benefit;
4. the overvoltage protection of pair protected equipment is more effective, and control system is simple and easy to realize.
Accompanying drawing explanation
Fig. 1 is the lightning arrester over-pressure safety device structure chart that in the embodiment of the present invention, pressure ratio is variable;
Fig. 2 is the lightning arrester overvoltage protection implementation method flow chart that in the embodiment of the present invention, pressure ratio is variable.
Embodiment
Below in conjunction with accompanying drawing, the present invention is described in further detail.
As Fig. 1, the lightning arrester over-pressure safety device that a kind of pressure ratio is variable, described device comprises lightning arrester series connection group, thyristor system and fault detection system; Connect with described lightning arrester lightning arrester in group of described thyristor system is in parallel, and described fault detection system is connected with described lightning arrester group parallel connection.
Described thyristor system comprises at least one anti-parallel thyristor and circuits for triggering thereof, and described circuits for triggering are in parallel with fault detection system.
Described lightning arrester series connection group is composed in series successively by two or more lightning arresters, and a lightning arrester anti-parallel thyristor in parallel, described lightning arrester series connection group is in parallel with protected equipment.
Described fault detection system comprises overvoltage detection system and over-current detection system; overvoltage detection system group of connecting with described protected equipment and described lightning arrester is all in parallel, and the over-current detection system lightning arrester of anti-parallel thyristor not in parallel in group of connecting with described lightning arrester is connected.
Described anti-parallel thyristor is inverse parallel gate level turn-off thyristor.
Described lightning arrester is metal oxide arrester.
The voltage magnitude at the protected equipment two ends of described fault detection system on-line monitoring and the current amplitude of lightning arrester branch road, if voltage magnitude exceedes definite value V1 or current amplitude when exceeding definite value A1, described fault detection system judges that overvoltage fault appears in protected equipment, described circuits for triggering send triggering signal to anti-parallel thyristor gate pole, control anti-parallel thyristor conducting, the lightning arrester that temporary short circuit is in parallel with anti-parallel thyristor; During the overvoltage failture evacuation of protected equipment; fault detection system detects the current amplitude flowing through the lightning arrester of anti-parallel thyristor not in parallel; if flow through the current amplitude of the lightning arrester of anti-parallel thyristor not in parallel lower than definite value A2; described circuits for triggering stop sending triggering signal; during voltage zero-cross, anti-parallel thyristor disconnects, and the lightning arrester of short circuit puts into operation again.
As Fig. 2, the lightning arrester overvoltage protection implementation method that a kind of pressure ratio is variable, said method comprising the steps of:
Step 1: carry out On-line Fault Detection;
Step 2: Logic judgment, if the voltage magnitude at protected equipment two ends is less than definite value V1 and the current amplitude of lightning arrester branch road is less than definite value A1, then returns step 1 and continues to perform; If the current amplitude that the voltage magnitude at protected equipment two ends rises to definite value V1 or lightning arrester branch road is greater than definite value A1, then perform step 3;
Step 3: circuits for triggering send triggering signal to anti-parallel thyristor gate pole, make anti-parallel thyristor conducting, the lightning arrester that short circuit is in parallel with it;
Step 4: the electric current on-line checkingi carrying out lightning arrester branch road;
Step 5: Logic judgment, if the current amplitude flowing through lightning arrester not in parallel with anti-parallel thyristor is not less than A2, then returns step 4 and continues to perform; If the current amplitude flowing through lightning arrester not in parallel with anti-parallel thyristor is less than A2, then circuits for triggering stop sending triggering signal, and anti-parallel thyristor disconnects, and the lightning arrester of short circuit accesses lightning arrester series connection group again, returns step 1.
Described on end, the variable lightning arrester overvoltage protection of this pressure ratio uses parts less, and structure is simple, and floor space is little; Residual voltage of arrester when limiting fault, can reduce pressure ratio, improve the level of protection of lightning arrester, improve system reliability, can directly apply to known excess voltage protection, will bring very large economic benefit; Device power electronic device cost used is low, reduces the comprehensive cost of the complete sets of equipment, takes into account economy and practicality, have good application prospect; More effective to the overvoltage protection of protected equipment, control system is simple and easy to realize.
Finally should be noted that: above embodiment is only in order to illustrate that technical scheme of the present invention is not intended to limit, although with reference to above-described embodiment to invention has been detailed description, those of ordinary skill in the field are to be understood that: still can modify to the specific embodiment of the present invention or equivalent replacement, and not departing from any amendment of spirit and scope of the invention or equivalent replacement, it all should be encompassed in the middle of right of the present invention.
Claims (5)
1. the lightning arrester over-pressure safety device that pressure ratio is variable, is characterized in that: described device comprises lightning arrester series connection group, thyristor system and fault detection system; Connect with described lightning arrester lightning arrester in group of described thyristor system is in parallel, and described fault detection system is connected with described lightning arrester group parallel connection;
Described thyristor system comprises at least one anti-parallel thyristor and circuits for triggering thereof, and described circuits for triggering are in parallel with fault detection system;
Described fault detection system comprises overvoltage detection system and over-current detection system, overvoltage detection system group of connecting with protected equipment and described lightning arrester is all in parallel, and the over-current detection system lightning arrester of anti-parallel thyristor not in parallel in group of connecting with described lightning arrester is connected;
The voltage magnitude at the protected equipment two ends of described fault detection system on-line monitoring and the current amplitude of lightning arrester branch road, if voltage magnitude exceedes definite value V1 or current amplitude when exceeding definite value A1, described fault detection system judges that overvoltage fault appears in protected equipment, described circuits for triggering send triggering signal to anti-parallel thyristor gate pole, control anti-parallel thyristor conducting, the lightning arrester that temporary short circuit is in parallel with anti-parallel thyristor; During the overvoltage failture evacuation of protected equipment; fault detection system detects the current amplitude flowing through the lightning arrester of anti-parallel thyristor not in parallel; if flow through the current amplitude of the lightning arrester of anti-parallel thyristor not in parallel lower than definite value A2; described circuits for triggering stop sending triggering signal; during voltage zero-cross, anti-parallel thyristor disconnects, and the lightning arrester of short circuit puts into operation again.
2. the lightning arrester over-pressure safety device that pressure ratio according to claim 1 is variable; it is characterized in that: described lightning arrester series connection group is composed in series successively by two or more lightning arresters; a lightning arrester anti-parallel thyristor in parallel, described lightning arrester series connection group is in parallel with protected equipment.
3. the lightning arrester over-pressure safety device that pressure ratio according to claim 1 and 2 is variable, is characterized in that: described anti-parallel thyristor is inverse parallel gate level turn-off thyristor.
4. the lightning arrester over-pressure safety device that pressure ratio according to claim 1 and 2 is variable, is characterized in that: described lightning arrester is metal oxide arrester.
5. the lightning arrester overvoltage protection implementation method that pressure ratio is variable, is characterized in that: said method comprising the steps of:
Step 1: carry out On-line Fault Detection;
Step 2: Logic judgment, if the voltage magnitude at protected equipment two ends is less than definite value V1 and the current amplitude of lightning arrester branch road is less than definite value A1, then returns step 1 and continues to perform; If the current amplitude that the voltage magnitude at protected equipment two ends rises to definite value V1 or lightning arrester branch road is greater than definite value A1, then perform step 3;
Step 3: circuits for triggering send triggering signal to anti-parallel thyristor gate pole, make anti-parallel thyristor conducting, the lightning arrester that short circuit is in parallel with it;
Step 4: the electric current on-line checkingi carrying out lightning arrester branch road;
Step 5: Logic judgment, if the current amplitude flowing through lightning arrester not in parallel with anti-parallel thyristor is not less than A2, then returns step 4 and continues to perform; If the current amplitude flowing through lightning arrester not in parallel with anti-parallel thyristor is less than A2, then circuits for triggering stop sending triggering signal, and anti-parallel thyristor disconnects, and the lightning arrester of short circuit accesses lightning arrester series connection group again, returns step 1.
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| CN201210267156.7A CN103124063B (en) | 2012-07-13 | 2012-07-13 | Arrester overvoltage protection device with variable voltage ratio and implementation method |
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| CN103630729B (en) * | 2013-11-13 | 2015-12-30 | 国家电网公司 | The primary connection device and method of test 1000kV lightning arrester reference voltage and leakage current |
| CN110535115A (en) * | 2019-09-24 | 2019-12-03 | 全球能源互联网研究院 | A kind of direct current controllable arrester device |
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