CN107294096A - A kind of determination unit function coefficient method for considering alternating current filter - Google Patents
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
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Abstract
A kind of method for the determination unit function coefficient for considering alternating current filter of the present invention, belong to generator failure analysis field, influence of the alternating current filter to circuit in circuit is have ignored for traditional unit function coefficient analytic approach, the method of determination unit function coefficient hair of the present invention based on subsynchronous concussion analysis, double tunning ripple alternating current filter is added in systems, including：Adjust AC harmonic filter to be added to rectification side in high voltage direct current converter system by more；Consider the capacity reactive compensation influences for adjusting AC harmonic filter to DC transmission system more；Three short circuit current between new direct current transportation converting plant and generating set on ac bus is obtained by short circuit calculation, three-phase shortcircuit capacity calculation methods on direct current transportation converting plant ac bus are improved, so as to further improve the method for determining unit function coefficient, improve the measurement accuracy of unit function coefficient method, it is highly reliable, this method is used in real process, the risk of subsynchronous concussion is greatly reduced.
Description
Technical Field
The invention belongs to the technical field of generator set fault analysis, and particularly designs a method for determining a generator set action coefficient based on subsynchronous oscillation analysis and considering an alternating current filter.
Background
At present, ten million kilowatt-level wind power bases are built in China, and large-scale wind power delivery becomes inevitable. The problem of subsynchronous oscillation may be induced by the ultra-high voltage alternating current transmission and the high voltage direct current transmission which are additionally provided with the series compensation capacitors as important modes of large-scale wind power delivery. Therefore, the method has great significance for the make internal disorder or usurp research on the large-scale wind power delivery subsynchronous oscillation mechanism. The high-voltage direct-current transmission is widely applied to the aspect of power transmission of a power system by virtue of advanced technical and economic advantages, and plays an important role in western-to-east power transmission projects in China. However, people also realize that under a certain system structure and operation mode, the HVDC is easy to cause the problem of subsynchronous oscillation (SSO) of a steam turbine generator unit connected with a rectification side, the problem of safety and stability of an alternating current and direct current system caused by SSO needs to be researched in the planning and operation of a modern power system, and the method for deeply analyzing and detecting the SSO caused by the direct current transmission system has great significance for the power system, and has important significance for researching the action mechanism of the SSO phenomenon and the inhibition measure thereof, and has important engineering value.
For the subsynchronous oscillation problem, a number of effective analysis methods have been developed, such as: the method comprises a unit action coefficient analysis method, an impedance scanning analysis method, a characteristic value analysis method, a complex torque coefficient analysis method and a time domain simulation analysis method. The unit action coefficient analysis method is mainly used for qualitatively analyzing and screening the units with subsynchronous array defense risks and the operation conditions, and has the advantages of simple calculation method, high speed, less required basic data and the like.
However, the influence of an alternating current filter in a circuit on the circuit is neglected by a traditional unit action coefficient analysis method, and alternating current generated by a generator needs to be filtered by the alternating current filter before being sent to a high-voltage direct current transmission line through a rectifying station, so that unnecessary current harmonic waves are bypassed to a power ground. The alternating current filter has reactive compensation effect on the system, influence factors of the alternating current filter are not considered completely, and subsynchronous oscillation risks of the unit are difficult to effectively reflect.
Disclosure of Invention
One of the purposes of the invention is to provide a method for determining the unit action coefficient based on the synchronous vibration square analysis, which considers the influence of an alternating current filter on a circuit, improves the traditional unit action coefficient calculation method, and perfects the parameter calculation method, so as to solve the reactive compensation influence of the alternating current filter on the circuit in the prior art and improve the calculation precision.
In some illustrative embodiments, the method for determining the coefficient of action of a unit based on subsynchronous oscillation analysis adds a double-tuned harmonic alternating current filter to a system, and comprises the following steps: adding a multi-tone alternating current harmonic filter to a rectification side of a high-voltage direct current conversion system; considering the reactive compensation influence of the multi-tone alternating current harmonic filter on the capacity of the direct current transmission system; three-phase short circuit cutoff on an alternating current bus between a new direct current transmission rectifying station and a generator set is obtained through short circuit calculation; and determining a new unit action coefficient according to the new short-circuit current, and analyzing the relation between the value and the detection subsynchronous oscillation.
Illustrative embodiments of the invention include the following advantages over the prior art:
the method for determining the action coefficient of the generator set is further improved by considering the reactive compensation condition of the alternating current filter between the rectifier station and the generator set in the high-voltage direct-current transmission system and improving the method for calculating the three-phase short-circuit capacity on the alternating current bus of the direct-current transmission rectifier station through short-circuit calculation, so that the measurement accuracy of the action coefficient method of the generator set is improved, the reliability is high, and the risk of subsynchronous oscillation is greatly reduced by adopting the method in the actual process.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:
FIG. 1 is a flow chart in accordance with an illustrative embodiment of the present invention;
fig. 2 is a circuit diagram of the high-voltage direct-current power transmission system of the embodiment.
FIG. 3 is a circuit diagram of a multi-tone AC harmonic filter and its equivalent;
FIG. 4 is an equivalent circuit diagram of the high-voltage direct-current transmission in normal operation and an equivalent circuit diagram of the f-point short circuit between a rectifier station and a generator set;
Detailed Description
In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. Specific components and circuits have not been shown but simplified to equivalent circuits, but those skilled in the art will understand the invention without additional specificity. In other instances, basic circuits, components, methods, and formulas have not been described in detail so as not to obscure the present invention.
The invention provides a method for determining a unit action coefficient by considering an alternating current filter, which is used for improving the unit action coefficient method for detecting the subsynchronous oscillation condition, forming a new unit action coefficient formula by considering the influence of the alternating current filter on high-voltage direct-current power transmission, improving the original unit action formula and further improving the calculation efficiency and accuracy.
As shown in fig. 1, a method for determining a unit action coefficient based on subsynchronous oscillation analysis is disclosed:
1. adding a multi-tone alternating current harmonic filter to a rectification side of a high-voltage direct current conversion system;
2. considering the reactive compensation influence of the multi-tone alternating current harmonic filter on the capacity of the direct current transmission system;
3. three-phase short circuit cutoff on an alternating current bus between a new direct current transmission rectifying station and a generator set is obtained through short circuit calculation;
4. and determining a new unit action coefficient according to the new short-circuit current, and analyzing the relation between the value and the detection subsynchronous oscillation.
As shown in fig. 2, a multi-tone ac harmonic filter is added to the rectification side of the existing hvdc transmission system to form a new system circuit diagram.
A multi-tone alternating current harmonic filter is added between a rectification station and a generator set of the high-voltage direct current transmission system, and the function of the multi-tone alternating current harmonic filter is to bypass unnecessary current harmonics to a power ground.
Compared with a single-tuned wave filter, the multi-tuned alternating current harmonic filter can simultaneously eliminate 2 harmonics with different frequencies, namely, the multi-tuned alternating current harmonic filter can be equivalent to two single-tuned wave filters.
From fig. 2, it is possible to derive fig. 4 as an equivalent circuit of a high voltage direct current transmission system taking into account an ac filter, whereby the short circuit calculation is performed according to fig. 3, 4.
Fig. 3 shows a circuit diagram of a multi-tone ac harmonic filter and its equivalent circuit diagram. Determining the impedance of the multi-tone alternating current harmonic filter according to the parameters of each resistor, each capacitor and each inductor of the multi-tone alternating current harmonic filter:
in the formula, Z (omega) is the equivalent impedance of a reactive power compensation part generated by the multi-tone alternating current harmonic filter; omega is the resonance frequency of the alternating current resonance filter; c1，L1Capacitance and inductance values of the series part of the AC harmonic filter respectively; ci，LiCapacitance and inductance values of the parallel parts of the AC harmonic filter respectively; k is the number of harmonic waves (k is more than or equal to 2) of different frequencies which can be filtered by the AC harmonic filter.
The formula summarizes the equivalent impedance of the reactive compensation part of the multi-tone alternating current harmonic filter, and is suitable for calculating the equivalent impedance of the basic multi-tone alternating current harmonic filter. When n is 0, the equivalent impedance of the single-tuned filter is equivalent, and when n is 1, the equivalent impedance of the multi-tuned filter is equivalent. When k is larger than or equal to 2, the alternating current filter can filter more than two harmonic waves with different frequencies.
The circuit load is equivalent to a motor with the same rated capacity as the generator set, and the short-circuit current is calculated according to the impedance of the multi-tone alternating current harmonic filter:
calculating the equivalent short-circuit current of the generator side:
calculating equivalent motor-side equivalent short-circuit current:
calculating short-circuit current of an alternating current bus at a rectifying side:
wherein,is the current of the circuit between the short-circuit point and the generator;is the generator equivalent electromotive force per unit value; x is the number of1，x2Respectively an equivalent reactance of the generator and an equivalent reactance of a power transmission line between the short-circuit point and the generator; z (omega) is the equivalent impedance of the multi-tone alternating current harmonic filter; i isBIs a line current reference value;is the equivalent current between the equivalent motor and the short-circuit point;is the motor equivalent electromotive force; x is the number of3The equivalent reactance of the transmission line between the equivalent motor and the short-circuit point;
according to the formula, the method for calculating the three-phase short-circuit capacity on the alternating-current bus of the direct-current transmission rectifier station in the new unit action coefficient formula is obtained, taking the three-phase short-circuit capacity on the alternating-current bus of the direct-current transmission rectifier station which does not include contribution of the ith generator set as an example:
wherein, SCi"to take into account the influence of the ac filter on the dc transmission, the three-phase short-circuit capacity on the ac bus of the dc transmission system rectifying station of the ith generator set is not calculated,the rated voltage of the line alternating current bus is,to account for the short circuit current affected by the multi-tone ac harmonic filter. SC'TOTFor considering the influence of the AC filter on the DC transmission, the three-phase short-circuit capacity on the AC bus of the rectifying station of the DC transmission system of the ith generator is calculated by the same calculation method as SC "i。
4. The method is characterized in that the calculation formula of the action coefficient of the original unit is improved to obtain a new calculation formula, and the calculation formula is characterized in that: coefficient SC in coefficient of action formula of unitiAnd SCTOTThe improvement is made to take into account the influence of the ac filter on the circuit:
in the formula, UIFi"is the action coefficient between the new ith generating set and the direct current transmission considering the influence of the alternating current filter; sHVDCRated capacity (MW) for the dc transmission system; siRated capacity (MVA) of the ith power generation unit. Wherein SHVDCAnd SiIt is known to plan and design power plants and dc transmission projects.
The above scheme is specifically described below:
in an alternating current and direct current power system, the problem of subsynchronous oscillation (SSO for short) caused by direct current transmission is that a steam turbine generator unit generates shafting resonance, and the shafting is damaged when the problem is serious. The unit action coefficient method is an analysis method provided for solving the problem of subsynchronous oscillation of a power system related to a direct-current power transmission system. When an HVDC (high voltage direct current) rectification station is close to a thermal power plant, subsynchronous oscillation is easily caused by interaction of a steam turbine generator shafting, so that a unit action coefficient analysis method is provided by the IEC/TR60919-3 standard and is used for evaluating the risk of subsynchronous oscillation caused by HVDC engineering.
The standard requires that, for any new hvdc transmission system, if there is a potential for torsional-steering interaction with the turbine generator, the specifications should provide the information needed to determine if extensive research needs to be undertaken and design studies using additional subsynchronous damping controllers (SSDC). The unit coefficient of action method can be expressed as:
in the formula UIFiThe action coefficient of the ith generating set; sHVDCThe rated capacity of the direct current transmission system; siThe rated capacity of the ith generating set; SC (Single chip computer)iFor three-phase short-circuit capacity on an alternating current bus of the direct current transmission rectifier station, the contribution of an ith generating set is not included when the short-circuit capacity is calculated, and the function of an alternating current filter is not included in synchronization; SC (Single chip computer)TOTAnd calculating the three-phase short-circuit capacity comprising contribution of the ith generating set on the alternating current bus of the direct current transmission rectifying station, wherein the short-circuit capacity does not comprise the action of an alternating current filter.
The invention aims to provide an improved calculation method considering the influence of an alternating current filter on the calculation of the short-circuit capacity of an overall circuit aiming at the incompleteness of the action coefficient formula of the existing unit.
In a high-voltage direct-current transmission system, an alternating-current filter is arranged on a rectifying side and used for filtering out unnecessary harmonic waves, the influence of the alternating-current filter on a system line is ignored by a traditional unit action coefficient method, but actually, the alternating-current filter has a reactive compensation effect on the line, so that the calculation of short-circuit capacity is influenced and is not ignored.
Where S is the line capacity, PdFor line active power, QfFor line reactive power, QEWithout taking into account the reactive power of the AC filter, Q, for the original lineLCReactive power compensated for the ac filter.
According to the invention, on the basis of the traditional unit action coefficient method, the influence of the alternating current filter on the line is considered, and the multi-tone alternating current harmonic filter is added into the system, so that the calculation accuracy is improved.
As shown in fig. 1, a method for determining a unit action coefficient considering the influence of an ac filter on a power transmission system based on the synchronous oscillation analysis is disclosed, which includes:
(1) adding a multi-tone alternating current harmonic filter to a rectification side of a high-voltage direct current conversion system;
(2) considering the reactive compensation influence of the multi-tone alternating current harmonic filter on the capacity of the direct current transmission system;
(3) obtaining three-phase short-circuit current on an alternating current bus between a new direct current transmission rectifier station and a generator set through short-circuit calculation;
(4) determining new unit action coefficient according to new short-circuit current, and analyzing the relation between the value and the detection subsynchronous oscillation
A multi-tone alternating current harmonic filter is added between a rectification station and a generator set of the high-voltage direct current transmission system, the structure of the multi-tone alternating current harmonic filter is shown as the figure 3, and the multi-tone alternating current harmonic filter has the function of bypassing unnecessary current harmonics to a power ground. Compared with a single-tuned wave filter, the multi-tuned alternating current harmonic filter can simultaneously eliminate 2 harmonics with different frequencies, namely, the multi-tuned alternating current harmonic filter can be equivalent to two single-tuned wave filters.
The specific calculation steps of the correction method are as follows:
(1) the coefficient of action of the unit is calculated according to a conventional method as follows:
(2) according to the parameters of each resistor, capacitor and inductor of the multi-tone AC harmonic filter shown in the attached figure 2, the impedance can be determined as follows:
in the formula, Z (omega) is the equivalent impedance of the reactive power compensation part generated by the double-tuned wave filter; omega is the resonance frequency of the alternating current resonance filter; c1，L1Capacitance and inductance values of the series part of the AC harmonic filter respectively; ci，LiCapacitance and inductance values of the parallel parts of the AC harmonic filter respectively; k is the number of harmonic waves (k is more than or equal to 2) of different frequencies which can be filtered by the AC harmonic filter.
The circuit load is equivalent to a motor with the same rated capacity as the generator set, and an equivalent circuit diagram as the figure 4 is formed. In the equivalent circuit, for convenient analysis, the rated capacities of the motor with equivalent load and the generator set to be measured are assumed to be the same. Generally, the influence of impedance on the circuit is neglected under the condition of high-voltage power transmission, and only the inductive reactance existing in the circuit is considered, so that an equivalent circuit diagram as shown in the figure 3 is obtained. According to the impedance of the multi-tone alternating current harmonic filter, calculating the short-circuit current:
(3) calculating the reference current values of the generator and the motor:
wherein S isBRated capacity of the generator to be tested and the equivalent motor; u shapeEIs the rated voltage of the equivalent circuit.
(4) To be provided withTaking a per unit value as a reference vector to obtain:
wherein, Uf(0)The voltage value at the short-circuit point f is such that its phase angle corresponds to the nominal voltage phase angle.
(5) According to the equivalent circuit of the attached figure 3, the current under normal work is obtained:
where P is the motor active power, cos θ is the line power factor, and θ is the power angle.
(6) To solve the per unit value
(7) The transient electromotive force of the generator can be obtained by working current, and the following steps are obtained:
wherein x is1Is equivalent to the generator reactance, x2And z is the equivalent impedance of the multi-tone alternating current harmonic filter.
(8) Similarly, the transient electromotive force of the motor can be obtained by:
wherein x is3Is the equivalent motor reactance.
(9) After short circuit, calculating each current according to the equivalent circuit:
a) calculating the equivalent short-circuit current of the generator side:
b) calculating equivalent motor-side equivalent short-circuit current:
(10) summing the equivalent short-circuit current of the generator side and the equivalent short-circuit current of the equivalent motor side, and calculating the short-circuit current of the alternating current bus of the rectifier side:
wherein,is the current of the circuit between the short-circuit point and the generator;is the generator equivalent electromotive force per unit value; x is the number of1，x2Respectively an equivalent reactance of the generator and an equivalent reactance of a power transmission line between the short-circuit point and the generator; z (omega) is the equivalent impedance of the multi-tone alternating current harmonic filter; i isBIs a line current standard value;is the equivalent current between the equivalent motor and the short-circuit point;is the motor equivalent electromotive force; x is the number of3The equivalent reactance of the transmission line between the equivalent motor and the short-circuit point;
the method for calculating the short-circuit current of the alternating-current bus at the rectifying side obtains a three-phase short-circuit capacity calculation method on the alternating-current bus of the direct-current transmission rectifying station in a new unit action coefficient formula, considers the influence of reactive compensation of an alternating-current filter between the rectifying side and a generator set on the whole short-circuit capacity, and takes the three-phase short-circuit capacity on the alternating-current bus of the direct-current transmission rectifying station without contribution of the ith generator set as an example:
wherein, SCi"to take into account the influence of the ac filter on the dc transmission, the three-phase short-circuit capacity on the ac bus of the dc transmission system rectifying station of the ith generator set is not calculated,the rated voltage of the line alternating current bus is,to account for the short circuit current affected by the multi-tone ac harmonic filter. SC'TOTFor considering the influence of the AC filter on the DC transmission, the three-phase short-circuit capacity on the AC bus of the rectifying station of the DC transmission system of the ith generator is calculated by the same calculation method as SC "i。
(12) Improving the calculation formula of the action coefficient of the original unit to obtain a new calculation formula, and calculating the coefficient SC in the original formulaiAnd SCTOTThe improvement is made to take into account the influence of the ac filter on the circuit:
in the formula,UIFi"is the action coefficient between the new ith generating set and the direct current transmission considering the influence of the alternating current filter; sHVDCRated capacity (MW) for the dc transmission system; siRated capacity (MVA) of the ith power generation unit. Wherein SHVDCAnd SiIt is known to plan and design power plants and dc transmission projects.
Claims (4)
1. A method for determining a unit action coefficient by considering an alternating current filter is characterized in that: the method for detecting the unit action coefficient of the subsynchronous oscillation condition is improved, the influence of an alternating current filter on high-voltage direct current transmission needs to be considered, a new unit action coefficient formula is formed, and the method specifically comprises the following steps:
step 1: adding a multi-tone alternating current harmonic filter to a rectification side of a high-voltage direct current conversion system;
step 2: considering the reactive compensation influence of the multi-tone alternating current harmonic filter on the capacity of the direct current transmission system;
and step 3: three-phase short circuit cutoff on an alternating current bus between a new direct current transmission rectifying station and a generator set is obtained through short circuit calculation;
and 4, step 4: and determining a new unit action coefficient according to the new short-circuit current, and analyzing the relation between the value and the detection subsynchronous oscillation.
2. A method of considering ac filter effects as claimed in claim 1 wherein: an alternating current harmonic filter is added between a rectification station and a generator set of the high-voltage direct current transmission system, and the function of the alternating current harmonic filter is to bypass unnecessary current harmonics to a power ground. Compared with a single-tuning harmonic filter, the multi-tuning alternating-current harmonic filter can simultaneously eliminate 2 or more than 2 harmonics with different frequencies, namely, the multi-tuning alternating-current harmonic filter can be equivalent to a plurality of single-tuning wave filters. Determining the impedance of the multi-tone alternating current harmonic filter according to the parameters of each resistor, each capacitor and each inductor of the multi-tone alternating current harmonic filter, then performing short circuit calculation, considering the reactive compensation influence of the alternating current filter, and calculating short circuit current:
in the formula, Z (omega) is the equivalent impedance of a reactive power compensation part generated by the multi-tone alternating current harmonic filter; omega is the resonance frequency of the alternating current resonance filter; c1，L1Capacitance and inductance values of the series part of the AC harmonic filter respectively; ci，LiCapacitance and inductance values of the parallel parts of the AC harmonic filter respectively; k is the number of harmonic waves (k is more than or equal to 2) of different frequencies which can be filtered by the AC harmonic filter.
The circuit load is equivalent to a motor with the same rated capacity as the generator set, and the short-circuit current is calculated according to the impedance of the multi-tone alternating current harmonic filter:
step 1: calculating the equivalent short-circuit current of the generator side:
step 2: calculating equivalent motor-side equivalent short-circuit current:
and step 3: calculating short-circuit current of an alternating current bus at a rectifying side:
wherein,is the current of the circuit between the short-circuit point and the generator;is the generator equivalent electromotive force per unit value; x is the number of1，x2Respectively an equivalent reactance of the generator and an equivalent reactance of a power transmission line between the short-circuit point and the generator; the equivalent impedance of the Z (omega) multi-modulation AC harmonic filter; i isBIs a line current standard value;is the equivalent current between the equivalent motor and the short-circuit point;is the motor equivalent electromotive force; x is the number of3The equivalent reactance of the transmission line between the equivalent motor and the short-circuit point.
3. The method for calculating the short-circuit current of the alternating-current bus at the rectifying side according to the claim 2 to obtain the three-phase short-circuit capacity calculation method on the alternating-current bus of the direct-current transmission rectifying station in the new unit action coefficient formula is characterized in that: considering the influence of reactive compensation of an alternating current filter between a rectifying side and a generating set on the whole short-circuit capacity, taking the three-phase short-circuit capacity on an alternating current bus of a direct current transmission rectifying station without contribution of the ith generating set as an example:
wherein, SCiIn order to consider the influence of the alternating current filter on the direct current transmission, the three-phase short-circuit capacity on the alternating current bus of the direct current transmission system rectifying station of the ith generating set is not calculated,the rated voltage of the line alternating current bus is,to account for the short circuit current affected by the multi-tone ac harmonic filter. SC'TOTIn order to consider the influence of the alternating current filter on the direct current transmission, the three-phase short circuit capacity on the alternating current bus of the direct current transmission system rectifying station of the ith generator is calculated by the same calculation method as SC ″i。
4. According to claims 1-3, the calculation formula of the action coefficient of the original unit is improved to obtain a new calculation formula, which is characterized in that: coefficient SC in coefficient of action formula of unitiAnd SCTOTThe improvement is made to take into account the influence of the ac filter on the circuit:
in the formula, UIFiThe action coefficient between the new ith generating set and the direct current transmission is considered in consideration of the influence of the alternating current filter; sHVDCRated capacity (MW) for the dc transmission system; siRated capacity (MVA) of the ith power generation unit. Wherein SHVDCAnd SiIt is known to plan and design power plants and dc transmission projects.
This formula is only applicable to the condition that all generating set diverse that connect on same generating line, and at this moment, each unit has different natural torsional vibration frequency, and the torsional vibration of every unit does not influence the torsional vibration of other units.
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Cited By (3)
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|---|---|---|---|---|
| CN109494717A (en) * | 2018-11-16 | 2019-03-19 | 国网新疆电力有限公司经济技术研究院 | It can avoid the safe capacity of short circuit screening technique and system of subsynchronous resonance risk |
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| CN113433483A (en) * | 2021-06-01 | 2021-09-24 | 南京南瑞继保电气有限公司 | On-line monitoring method and monitoring device for short-circuit current of alternating current system |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109494717A (en) * | 2018-11-16 | 2019-03-19 | 国网新疆电力有限公司经济技术研究院 | It can avoid the safe capacity of short circuit screening technique and system of subsynchronous resonance risk |
| CN112749486A (en) * | 2020-12-29 | 2021-05-04 | 南方电网科学研究院有限责任公司 | Method and device for batch calculation of unit action coefficients and storage medium |
| CN112749486B (en) * | 2020-12-29 | 2023-05-16 | 南方电网科学研究院有限责任公司 | Method, device and storage medium for batch calculation of unit action coefficients |
| CN113433483A (en) * | 2021-06-01 | 2021-09-24 | 南京南瑞继保电气有限公司 | On-line monitoring method and monitoring device for short-circuit current of alternating current system |
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| CN107294096B (en) | 2019-01-11 |
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