CN104977514A - Determination method of corona onset voltage of high-voltage direct-current circuit - Google Patents
Determination method of corona onset voltage of high-voltage direct-current circuit Download PDFInfo
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- CN104977514A CN104977514A CN201510378757.9A CN201510378757A CN104977514A CN 104977514 A CN104977514 A CN 104977514A CN 201510378757 A CN201510378757 A CN 201510378757A CN 104977514 A CN104977514 A CN 104977514A
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Abstract
The invention provides a determination method of a corona onset voltage of a high-voltage direct-current circuit. The determination method comprises: constructing a voltage-audible noise A-sound level curve and a voltage-audible noise high-frequency component curve of a high-voltage direct-current circuit; step 2, obtaining a corona onset voltage stop value based on the voltage-audible noise A-sound level curve and a corona onset voltage initial value based on the voltage-audible noise high-frequency component curve; and step 3, according to the corona onset voltage stop value and the corona onset voltage initial value, calculating a discharge inception voltage. Compared with the prior art, the provided determination method has the following beneficial effects: the audible noises are used as a decision content; the contact with the high voltage is avoided; the whole test process is safe; and the corona onset field intensity of the ultra-/extra-high-voltage direct-current circuit can be obtained accurately from the perspective of the audible noises.
Description
Technical field
The present invention relates to direct current transportation field, be specifically related to a kind of hvdc transmission line discharge inception voltage decision method.
Background technology
The electromagnetic environment problem of UHV transmission line is the key technical problem must considered in extra-high voltage alternating current-direct current Transmission Line Design, construction and operation, and it is directly related with the corona characteristic of transmission line of electricity.Consider economy, transmission line of electricity is usually designed to the corona discharge allowed under normal operating voltage to a certain degree.Corona discharge will produce audible noise, radio interference and corona loss etc., can affect to environment and operation.Consider from construction and the many-side such as operating cost and environmental protection, appropriate design wire, moderate control corona effect, extremely important to development UHV transmission.
These problems that corona causes are the key technical problems must considered in power transmission engineering design, construction and operation.In addition, along with the development of economy and the enhancing of common people's environmental consciousness, its environmental impact issues more and more receives the concern of people, is subject to the strict restriction of environmental protection, becomes decision transmission line structure, affect the key factor of construction cost etc.Therefore, the research of UHV transmission technology be strengthened, reduce and avoid generation and the corona effect of corona, the corona characteristic that wire must be analyzed and the series of problems brought thereof.Wherein, the accurate judgement of DC line corona inception voltage and corona inception field strength be carry out the systematic study of wire discharge inception voltage before need a major issue first solving.Particularly 800kV, 1100kV extra-high voltage direct-current transmission, corona inception voltage and corona inception field strength also do not have systematic research achievement at home and abroad.Therefore, need in conjunction with actual conditions, obtain the corona inception voltage of 800kV extra high voltage direct current transmission line and the result of study of corona inception field strength.
Wire discharge inception voltage is the important parameter of research conductor corona characteristic, for instructing great significance for design that is super, UHV transmission line.But the current determination methods to wire discharge inception voltage disunity.At present, the test method of wire and the initial corona characteristic of equipment mainly contains range estimation, night vision device measurement, corona current waveform measurement, digital vedio recording picture analysis etc.The result difference that different measuring method obtains is comparatively large, is exactly same measuring method, and different people, different observation place measurement results can be variant; Due to the impact of environmental baseline, also may there is larger difference in the result of different time measurements, and the method for testing of test is by the result of direct influence research.
Discharge inception voltage can be calculated by theory, also can be judged by test, but before corona discharge problem in high voltage subject thoroughly solves, the judgement being carried out discharge inception voltage by test is more reliable.Patent CN100595600C gives a kind of method of DC equipment discharge inception voltage being carried out to relative air density calibration based on existing theoretical method, mainly theory calculate.Patent CN101738552A is based on the 750kV transmission line wire discharge inception voltage high-altitude correction method of corona loss experiment curv.Patent CN101477159A gives extra-high voltage and super-high voltage line conductor discharge inception voltage high-altitude correction method.Patent CN101187686 gives the discharge inception voltage of pipe bus and the test decision method of extinction voltage, this patent based on pipe bus fixing with do not fix corona point discharge inception voltage judged, but fixing with do not fix corona point it is determined that the presence of more subjectivity.Patent 102680781B proposes middle pressure twisted polyethylene cable without covering initial corona voltage test method, lays particular emphasis on subjects, and trial voltage is alternating voltage.Patent CN103675629A proposes a kind of electrode discharge inception voltage Forecasting Methodology based on Field signature amount, but it does not provide the discharge inception voltage decision method of often kind of electrode.Patent CN102508122B gives High aititude transmission line hardware discharge inception voltage adjustment for altitude method.
The bloom of actual outdoor ultra-high/extra-high voltage DC power transmission line is a process, along with the rising of voltage, on transmission line of electricity, there is discontinuity corona discharge in certain point of local before this, then be that intermittent point of discharge increases gradually, occurring more stable and fewer point of discharge after developing deeply, is finally all fronts corona discharges comprehensively.Thus actual split conductor is difficult to determine a discharge inception voltage accurately, and its bloom is a process, certain point of thus usually said transmission line of electricity discharge inception voltage in fact bloom process.
Utilize the DC corona cage in extra-high voltage experiment base, carrying out the discharge inception voltage decision method research of DC line audible noise, is follow-up basic prerequisite of carrying out the research of UHVDC Transmission Lines bloom field intensity.Once solve this difficult problem, the bloom field intensity test of a large amount of DC wire just can be done systematically in corona cage, for the bloom characteristic grasping true type split conductor better carries out tachnical storage.
Summary of the invention
In order to meet the needs of prior art, the invention provides a kind of hvdc transmission line discharge inception voltage decision method.
Technical scheme of the present invention is:
Described method comprises:
Step 1: the voltage-audible noise A sound level curve and the voltage-audible noise high fdrequency component curve that build hvdc transmission line;
Step 2: according to described voltage-audible noise A sound level curve acquisition discharge inception voltage stop value, and according to described voltage-audible noise high fdrequency component curve acquisition discharge inception voltage initial value;
Step 3: according to described discharge inception voltage stop value and discharge inception voltage calculation of initial value discharge inception voltage.
Preferably, voltage-audible noise A sound level curve is built in described step 1 and voltage-audible noise high fdrequency component curve comprises:
Step 1-1: ground unrest A sound level and the spectrum component thereof of measuring described hvdc transmission line;
Step 1-2: the initial voltage of setting hvdc transmission line, step-down or boost at equal intervals at equal intervals, measures the audible noise A sound level A under each electric pressure from described initial voltage
iwith high fdrequency component f
i, i is the sequence number of electric pressure;
Step 1-3: choose described audible noise A sound level A
iin be greater than the described audible noise A sound level of ground unrest A sound level and the test data of high fdrequency component, matching is carried out to the test data of audible noise A sound level and obtains described voltage-audible noise A sound level curve, matching is carried out to the test data of high fdrequency component and obtains voltage-audible noise high fdrequency component curve;
Preferably, ground unrest A sound level measurement and the high fdrequency component of carrying out described hvdc transmission line in described step 1-2 are measured simultaneously;
Preferably, in described step 1-2 when extraneous conditional stability, ground unrest A sound level measurement and the high fdrequency component of carrying out described hvdc transmission line are respectively measured;
Preferably, in described step 1-3, matching is carried out to measurement data and comprise linear fitting and high order curve fitting process;
Preferably, obtain discharge inception voltage stop value in described step 2 to comprise:
Using the magnitude of voltage of the intersection of the ground unrest A sound level of described voltage-audible noise A sound level curve and hvdc transmission line as discharge inception voltage stop value;
Preferably, obtain discharge inception voltage initial value in described step 2 to comprise:
Using the magnitude of voltage of the high fdrequency component intersection of the ground unrest of described voltage-audible noise high fdrequency component curve and hvdc transmission line as discharge inception voltage initial value;
Preferably, described discharge inception voltage is the mean value of described discharge inception voltage stop value and discharge inception voltage initial value;
Preferably, described discharge inception voltage is described discharge inception voltage stop value and discharge inception voltage initial value
distance values, n > 1.
Compared with immediate prior art, excellent effect of the present invention is:
1, a kind of hvdc transmission line discharge inception voltage decision method provided by the invention, adopt audible noise as decision content, do not contact with high pressure, whole process of the test is safer, can obtain the bloom field intensity of ultra-high/extra-high voltage DC line more exactly from audible noise angle;
2, a kind of hvdc transmission line discharge inception voltage decision method provided by the invention, all these actual conditions of process according to the bloom of split conductor in engineering, propose bloom and start voltage and bloom final voltage, to the description more science of this physical quantity of discharge inception voltage;
3, a kind of hvdc transmission line discharge inception voltage decision method provided by the invention, improves the Research Ability of extra high voltage direct current transmission line electromagnetic environment, for extra-high voltage direct-current engineering construction provides more strong technical support.
Accompanying drawing explanation
Below in conjunction with accompanying drawing, the present invention is further described.
Fig. 1: a kind of hvdc transmission line discharge inception voltage decision method schematic diagram in the embodiment of the present invention;
Fig. 2: in the embodiment of the present invention, the discharge inception voltage of actual wire judges schematic diagram;
Partial enlarged drawing in Fig. 3: Fig. 2 near actual wire bloom.
Embodiment
Be described below in detail embodiments of the invention, the example of described embodiment is shown in the drawings, and wherein same or similar label represents same or similar element or has element that is identical or similar functions from start to finish.Be exemplary below by the embodiment be described with reference to the drawings, be intended to for explaining the present invention, and can not limitation of the present invention be interpreted as.
A kind of hvdc transmission line discharge inception voltage decision method provided by the invention, adopt audible noise as decision content, do not contact with high pressure, whole process of the test is safer.The embodiment of mesohigh DC line discharge inception voltage decision method of the present invention as shown in Figure 1, is specially:
The step of the method comprises:
1, voltage-audible noise A sound level curve and the voltage-audible noise high fdrequency component curve of hvdc transmission line is built:
(1) ground unrest A sound level and the spectrum component thereof of hvdc transmission line is measured.
(2) set the initial voltage of hvdc transmission line, from initial voltage, step-down or boost at equal intervals from initial voltage at equal intervals, measures the audible noise A sound level A under each electric pressure
iwith high fdrequency component f
i, i is the sequence number of electric pressure.
Can in carry out simultaneously the ground unrest A sound level of hvdc transmission line and high fdrequency component measured, also can when extraneous conditional stability, ground unrest A sound level measurement and the high fdrequency component that carry out hvdc transmission line are respectively measured.The present embodiment high frequency components is the 8kHz component of audible noise, also can be other frequency components.
(3) audible noise A sound level A is chosen
iin be greater than the audible noise A sound level of ground unrest A sound level and the test data of high fdrequency component, matching is carried out to the test data of audible noise A sound level and obtains voltage-audible noise A sound level curve, matching is carried out to the test data of high fdrequency component and obtains voltage-audible noise high fdrequency component curve.
In the present embodiment, matching is carried out to measurement data and comprise linear fitting, high order curve fitting process and other Function Fitting methods.
2, according to voltage-audible noise A sound level curve acquisition discharge inception voltage stop value, and according to voltage-audible noise high fdrequency component curve acquisition discharge inception voltage initial value.
In the present embodiment using the magnitude of voltage of the intersection of the ground unrest A sound level of voltage-audible noise A sound level curve and hvdc transmission line as discharge inception voltage stop value.Using the magnitude of voltage of the intersection of the high fdrequency component of the ground unrest of voltage-audible noise high fdrequency component curve and hvdc transmission line as discharge inception voltage initial value.
3, according to discharge inception voltage stop value and discharge inception voltage calculation of initial value discharge inception voltage.
Discharge inception voltage is the mean value of discharge inception voltage stop value and discharge inception voltage initial value, also can be discharge inception voltage stop value and discharge inception voltage initial value
distance values, n > 1, n=3 in the present embodiment.
Another embodiment of mesohigh DC line discharge inception voltage decision method of the present invention is:
(1) ground unrest A sound level and the spectrum component thereof of hvdc transmission line is measured, Measuring Time more than 1 hour.
(2) initial voltage setting hvdc transmission line is 1100kV, and step-down at equal intervals from initial voltage, measures the audible noise A sound level A under each electric pressure
iwith high fdrequency component f
icomprise 1000kV, 1050kV, 1000kV, 950kV, 900kV, 850kV, 800kV, 750kV, 700kV, 650kV, 600kV, 550kV, 500kV, 450kV and 400kV, from 2 minutes to 1 hour not etc., voltage is lower, and Measuring Time is longer for Measuring Time under each electric pressure.
(3) audible noise A sound level A is chosen
iin be greater than the audible noise A sound level of ground unrest A sound level and the test data of high fdrequency component, adopt the test data of quadratic fit method to audible noise A sound level to carry out matching and obtain voltage-audible noise A sound level curve, and adopt quadratic fit method to carry out matching to the test data of high fdrequency component to obtain voltage-audible noise high fdrequency component curve.
(4) according to voltage-audible noise A sound level curve acquisition discharge inception voltage stop value, as shown in right vertical line in Fig. 2 and Fig. 3, and according to voltage-audible noise high fdrequency component curve acquisition discharge inception voltage initial value, as shown in left side vertical line in Fig. 2 and Fig. 3.
(5) according to discharge inception voltage stop value and discharge inception voltage calculation of initial value discharge inception voltage.
The present embodiment mesohigh DC line discharge inception test adopts bipolar corona cage to test, and wherein single cage cross section is 10m × 10m, long 70m, and wide 20.5m has the spacer region of 0.5m between two cage, spacer region can be removed when carrying out the test of bipolar corona cage.Hvdc transmission line adopts 6 division JL/G1A-720/50-45/7 wires, and heading spacing is 0.45m, hangs on center in positive and negative electrode corona cage.
Utilize corona cage carry out hvdc transmission line wire audible noise test time, measuring sonde be arranged in span center xsect on, cage wall 4 directions of test lead place cage face wire arrangements 4 measuring sondes.The 3560-C noise automatic measurement system that audible noise measuring instrument adopts B & K company of Denmark to produce, records 1 A sound level and frequency spectrum every 1s, finally carries out statistical processing and analysis to measurement data again.
To 6 × 720mm in corona cage
2the audible noise of wire carries out the statistical study of said method, as shown in Figures 2 and 3, show that discharge inception voltage stop value is Uc=542.1kV, discharge inception voltage initial value Up=394.6kV.If discharge inception voltage is the mean value of discharge inception voltage stop value and discharge inception voltage initial value, then discharge inception voltage stop value Uc=468.4kV; If discharge inception voltage is discharge inception voltage stop value and discharge inception voltage initial value
distance values, then discharge inception voltage stop value Uc=443.8kV.
Finally should be noted that: described embodiment is only some embodiments of the present application, instead of whole embodiments.Based on the embodiment in the application, those of ordinary skill in the art are not making the every other embodiment obtained under creative work prerequisite, all belong to the scope of the application's protection.
Claims (9)
1. a hvdc transmission line discharge inception voltage decision method, is characterized in that, described method comprises:
Step 1: the voltage-audible noise A sound level curve and the voltage-audible noise high fdrequency component curve that build hvdc transmission line;
Step 2: according to described voltage-audible noise A sound level curve acquisition discharge inception voltage stop value, and according to described voltage-audible noise high fdrequency component curve acquisition discharge inception voltage initial value;
Step 3: according to described discharge inception voltage stop value and discharge inception voltage calculation of initial value discharge inception voltage.
2. the method for claim 1, is characterized in that, described step 1 comprises:
Step 1-1: ground unrest A sound level and the spectrum component thereof of measuring described hvdc transmission line;
Step 1-2: the initial voltage of setting hvdc transmission line, step-down or boost at equal intervals at equal intervals, measures the audible noise A sound level A under each electric pressure from described initial voltage
iwith high fdrequency component f
i, i is the sequence number of electric pressure;
Step 1-3: choose described audible noise A sound level A
iin be greater than the described audible noise A sound level of ground unrest A sound level and the test data of high fdrequency component, matching is carried out to the test data of audible noise A sound level and obtains described voltage-audible noise A sound level curve, matching is carried out to the test data of high fdrequency component and obtains voltage-audible noise high fdrequency component curve.
3. method as claimed in claim 2, is characterized in that, ground unrest A sound level measurement and the high fdrequency component of carrying out described hvdc transmission line in described step 1-2 are measured simultaneously.
4. method as claimed in claim 2, is characterized in that, in described step 1-2 when extraneous conditional stability, ground unrest A sound level measurement and the high fdrequency component of carrying out described hvdc transmission line are respectively measured.
5. method as claimed in claim 2, is characterized in that, carry out matching comprise linear fitting and high order curve fitting process in described step 1-3 to measurement data.
6. the method for claim 1, is characterized in that, obtains discharge inception voltage stop value and comprise in described step 2:
Using the magnitude of voltage of the intersection of the ground unrest A sound level of described voltage-audible noise A sound level curve and hvdc transmission line as discharge inception voltage stop value.
7. the method for claim 1, is characterized in that, obtains discharge inception voltage initial value and comprise in described step 2:
Using the magnitude of voltage of the high fdrequency component intersection of the ground unrest of described voltage-audible noise high fdrequency component curve and hvdc transmission line as discharge inception voltage initial value.
8. the method for claim 1, is characterized in that, described discharge inception voltage is the mean value of described discharge inception voltage stop value and discharge inception voltage initial value.
9. the method for claim 1, is characterized in that, described discharge inception voltage is described discharge inception voltage stop value and discharge inception voltage initial value
distance values, n > 1.
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Cited By (4)
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| CN107478326A (en) * | 2017-09-15 | 2017-12-15 | 中国电力科学研究院 | A kind of multichannel audible noise synchronized measurement system and method |
| CN110361635A (en) * | 2018-11-26 | 2019-10-22 | 华北电力大学 | It is a kind of for determining the method and device of corona inception voltage |
| CN110456238A (en) * | 2019-07-26 | 2019-11-15 | 苏州微木智能系统有限公司 | A kind of corona discharge ion source detection method and system |
| CN111505449A (en) * | 2020-03-24 | 2020-08-07 | 中国电力科学研究院有限公司 | Method and system for judging direct-current corona-starting field intensity of split conductor |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107478326A (en) * | 2017-09-15 | 2017-12-15 | 中国电力科学研究院 | A kind of multichannel audible noise synchronized measurement system and method |
| CN110361635A (en) * | 2018-11-26 | 2019-10-22 | 华北电力大学 | It is a kind of for determining the method and device of corona inception voltage |
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| CN110456238A (en) * | 2019-07-26 | 2019-11-15 | 苏州微木智能系统有限公司 | A kind of corona discharge ion source detection method and system |
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| CN111505449A (en) * | 2020-03-24 | 2020-08-07 | 中国电力科学研究院有限公司 | Method and system for judging direct-current corona-starting field intensity of split conductor |
| CN111505449B (en) * | 2020-03-24 | 2022-12-02 | 中国电力科学研究院有限公司 | Method and system for judging direct current corona onset field intensity of split conductor |
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