CN111404128B - Simulation modeling analysis method for analyzing response capability of fuse in frequency converter of direct-current power system to short-circuit current - Google Patents
Simulation modeling analysis method for analyzing response capability of fuse in frequency converter of direct-current power system to short-circuit current Download PDFInfo
- Publication number
- CN111404128B CN111404128B CN202010190391.3A CN202010190391A CN111404128B CN 111404128 B CN111404128 B CN 111404128B CN 202010190391 A CN202010190391 A CN 202010190391A CN 111404128 B CN111404128 B CN 111404128B
- Authority
- CN
- China
- Prior art keywords
- fuse
- direct current
- copper bar
- circuit
- frequency converter
- 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.)
- Active
Links
- 238000004458 analytical method Methods 0.000 title claims abstract description 13
- 230000004044 response Effects 0.000 title claims abstract description 13
- 238000005094 computer simulation Methods 0.000 title claims abstract description 12
- 238000004364 calculation method Methods 0.000 claims abstract description 24
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 75
- 229910052802 copper Inorganic materials 0.000 claims description 75
- 239000010949 copper Substances 0.000 claims description 75
- 239000003990 capacitor Substances 0.000 claims description 23
- 238000004088 simulation Methods 0.000 claims description 7
- 238000009825 accumulation Methods 0.000 claims description 6
- 239000000178 monomer Substances 0.000 claims description 6
- 230000035699 permeability Effects 0.000 claims description 6
- 230000006855 networking Effects 0.000 abstract description 8
- 238000000034 method Methods 0.000 abstract description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 5
- 229910052744 lithium Inorganic materials 0.000 description 5
- 238000010586 diagram Methods 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
- H02H7/268—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured for dc systems
Landscapes
- Inverter Devices (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
The invention discloses a simulation modeling analysis method for analyzing the response capability of a fuse in a frequency converter of a direct-current power system to a short-circuit current. The method can accurately obtain the I of the fuse in each device when the direct current of the frequency converter is short-circuited by establishing the calculation model2And T, the reliability of selective fault removal of the direct-current networking system can be effectively verified, and a basis can be provided for design and type selection of the fuse.
Description
Technical Field
The invention relates to an electrical system applied to a ship, in particular to a simulation modeling analysis method for analyzing the response capability of a fuse in a frequency converter of a direct-current power system to short-circuit current.
Background
The networking mode of the C-PP direct-current networking technology is a direct-current network, namely a shore power supply and a lithium battery pack on a ship are connected with a power load through a C-PP frequency converter networking, and the whole electric power is distributed through a direct-current bus with high efficiency and high dynamic characteristics. In a C-PP system, when a short-circuit fault occurs in a certain device, an obvious overcurrent may occur at a dc bus, a frequency converter or an ac output terminal, and if the fault device is not selectively removed, a ship may be completely powered off, the ship may lose maneuverability, that is, lose propulsion capability, and a ship collision or a ship fire may be seriously caused.
Therefore, when a short-circuit failure occurs in a certain device, the failed device needs to be removed from the entire system as soon as possible to avoid the enlargement of the failure. According to the selective overcurrent protection guidelines for marine power systems, the CCS code provides for the selective implementation of faults, which provides for the automatic switching of the electrical system, and all short-circuit protection, including critical equipment circuits, should be selective, except in the case of double sets of critical equipment powered by different distribution panels. Meanwhile, on the premise of satisfying selective protection, a fault circuit should be cut off as soon as possible, thereby reducing the influence on the power system and the risk of fire.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the simulation modeling analysis method for analyzing the response capability of the fuse in the frequency converter of the direct-current power system to the short-circuit current is provided.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a simulation modeling analysis method for analyzing the response capability of a fuse in a frequency converter of a direct current power system to a short-circuit current is specifically as follows;
1) building a cabinet model, for example, building a single cabinet, modeling a capacitor C formed by a frequency converter thereinM1And its equivalent direct current resistance RESRcThe fuse comprises a series model, two groups of fuses of direct current buses are respectively connected with the input side and the output side of a frequency converter, the fuses of each group of direct current buses comprise two fuse monomers which are arranged in parallel, the fuse monomers are modeled into a resistor, and cables or copper bars between the input side and the output side of the frequency converter and the fuses are marked as CO 1; cables or copper bars from the two groups of fuses to the direct current busbar are marked as CO 2; the copper bar on the direct current bus is marked as CO3 and consists of a positive group and a negative group; the single cables or copper bars CO1 and CO2 are simplified into a model of series connection of a resistor and an inductor, the single copper bar CO3 is simplified into a model of series connection of a resistor and an inductor, and the capacitor of the copper bar CO3 is simplified into an equivalent capacitor C arranged between a positive direct current bus and a negative direct current busint(ii) a (ii) a Calculating to obtain specific parameters of the cabinet body model; the specific calculation is as follows:
(a) calculating the equivalent direct current resistance through the steady-state direct current power consumption and the rated current of the fuse, and obtaining the following formula:
equivalent short-circuit resistance R of fuse in simulation model in short-circuit stateSCFuseModeling by adopting a mode of carrying out short-circuit test on the fuse and carrying out curve fitting after acquiring an actual fusing waveform of the fuse;
(b) calculating the value R of the resistance and the direct current inductance formed by simplifying the cable or the copper barco1,Rco2,Rco3,Lco1,Lco2,Lco3Calculating the equivalent capacitance C of the copper bar CO3int(ii) a The value L of the direct current inductance formed by simplifying the calculation copper barco1,Lco2,Lco3The calculation formula of (2) is:
wherein: magnetic permeability mu in vacuum0Is a constant of 4 π × 10-7(ii) a The average distance a between the positive copper bar and the negative copper bar; the unit m; the width b of the single-phase copper bar is calculated by overlapping the widths if the single-phase copper bar is a plurality of copper bars; the unit m; the height h of the copper bar; the unit m; the length l of the single-phase copper bar is unit m;
2) establishing a cabinet simplified circuit model, and removing a capacitor C between the positive and negative direct current busesM1And its equivalent direct current resistance RESRcThe external resistance is equivalent to a resistance Ra, and a capacitor C is arranged between the positive and negative direct current busesM1And its equivalent direct current resistance RESRcThe external inductor is equivalent to an inductor La; the resistance on the positive and negative direct current buses is equivalent to a resistance Rb, and the inductance on the positive and negative direct current buses is equivalent to an inductance Lb, so that a simplified model is obtained, wherein:
3) establishing a system circuit model, and establishing an integral circuit model of the C-PP system including all cabinets by referring to the steps;
4) obtaining I of fuses in each internal frequency converter of a cabinet when direct current of the internal frequency converter of a cabinet is short-circuited by using MATLAB simulation calculation2T；
Accumulation of current and time of the fault loop fuse reaches its fuse I quickly2T, cutting off a fault loop; if the current and time accumulation of all other non-fault loop fuses does not exceed the pre-arc I of the corresponding fuse when the fault loop is cut off2T, indicating that the non-faulty loop is not affected; if the current and time of the non-fault circuit fuse exceeds the pre-arc I of the corresponding fuse when the fault circuit is cut off2T, the fuse at the position needs to be replaced by a fuse I before the arc2T larger fuse.
Preferably, the calculation of the value R of the resistance into which the cable or the copper bar is simplified is performedco1,Rco2,Rco3The specific calculation formula is as follows:
wherein: resistance value R, unit omega; resistivity ρ, unit: omega m2(ii)/m; length l of cable or copper bar, unit: m; the sectional area A of the cable or the copper bar, unit: m is2。
Preferably, the calculation of the value L of the direct current inductance simplified by the cable is carried outco1,Lco2,Lco3The calculation formula of (2) is:
wherein: magnetic permeability mu in vacuum0Is a constant of 4 π × 10-7(ii) a The unit H/m; the central distance a of 2 round cables is unit m; radius r of the cableLThe unit m; length of single cable l, unit m.
As a preferable scheme, the copper barThe equivalent capacitance calculation formula of CO3 is:
wherein epsilondiIs a capacitance constant with a value of 8.854 × 10-12F/m, a is the average distance between the positive copper bar and the negative copper bar, m and b are the widths of the copper bars, and m and h are the lengths of the single-phase copper bars and m.
The invention has the beneficial effects that: the method can accurately obtain the I of the fuse in each device when the direct current of the frequency converter is short-circuited by establishing the calculation model2And T, the reliability of selective fault removal of the direct-current networking system can be effectively verified, and a basis can be provided for design and type selection of the fuse.
And when a frequency converter on a certain section of direct current bus has a direct current short circuit, the power electronic switch can cut out the fault half board from the direct current bus of the non-fault half board, so that for analyzing the direct current short circuit of the frequency converter, only all equipment on the single section of direct current bus where the fault frequency converter is located needs to be considered, and all the equipment on the whole board does not need to be analyzed.
Drawings
FIG. 1 is a single line diagram of a DC power system of the present invention;
FIG. 2 is a schematic diagram of the DC short circuit at the outer side of the capacitor of the frequency converter according to the present invention;
FIG. 3 is a schematic diagram of the DC short circuit inside the capacitor of the frequency converter according to the present invention;
FIG. 4 is a simulation model of the M1 cabinet of the present invention;
FIG. 5 is an equivalent circuit model of copper bar CO3 in the present invention;
FIG. 6 is a cable model of the present invention;
FIG. 7 is a copper bar model of the present invention;
FIG. 8 is a circuit model of the M1 cabinet of the present invention;
FIG. 9 is a simplified circuit model of the M1 cabinet of the present invention;
FIG. 10 is an overall model of the system of the present invention.
In the figure: 1-a shore power supply; 2-a lithium battery; networking a 3-C-PP frequency converter; 4-a generator set; 5-a propulsion motor; 6-daily load; 7-power electronic switches; 31-a frequency converter; 311-a power module; 312-capacitance; a 32-fuse; 33-direct current bus bar.
Detailed Description
Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
As shown in fig. 1, the direct current power system comprises a shore power supply 1 on a ship, a lithium battery 2 and a generator set 4, wherein the shore power supply 1, the lithium battery 2 and the generator set 4 are connected with a daily load 4 and a propulsion motor 5 through a C-PP frequency converter network 3; the direct current power system at least comprises two groups of C-PP frequency converter networking 3, and the C-PP frequency converter networking 3 are connected through a power electronic switch 7; the C-PP frequency converter network 3 comprises a frequency converter 31, a fuse 32 and a direct current bus 33; one side of the frequency converter 31 is connected with a shore power supply 1 or a lithium battery pack 2, and the other side is connected with a direct-current bus bar 33 through a fuse 32; as shown in fig. 2 and 3, the frequency converter 31 includes a power module 311 and a capacitor 312.
When two sections of direct-current busbars 33 connected with a port and a starboard in a direct-current power system are in contact to generate short circuit or a frequency converter 31 generates direct-current short circuit, a power electronic switch 7 connected with the two sections of direct-current busbars 33 can be tripped within 15-25 microseconds, so that a fault half board is cut out of direct-current busbars of non-fault half boards, the short-circuit busbars and normally-working busbars are physically isolated, the operation capacity of equipment on the residual direct-current busbars is guaranteed, and selective protection of faults is realized;
when the frequency converter 31 has a dc short circuit, there are two short circuit situations, fig. 2 shows that the dc short circuit is on the outer side of the capacitor 312, and fig. 3 shows that the dc short circuit is on the inner side of the capacitor 312;
the short circuit loops in both cases are similar, when a short circuit occurs, P1Capacitor C of1Will discharge to the short-circuit point and deliver current I1，P2Capacitor C of2Discharging the short-circuit point and supplying a current I through a relatively long circuit2；I1Does not pass through the fuse, I2Will flow through the fuse and may cause the fuse to blow;
due to C1Smaller, the resistance of the loop is also smaller, so the discharge time constant of the whole loop is shorter, I1The attenuation is fast; due to C2Is generally larger (C)2The capacitance of all non-fault modules) and the circuit is longer and includes the impedance of the fuse, so the discharge time constant of the whole circuit is longer;
fuse F1Due to I2I of electric current2T is accumulated and fused, so that a loop is cut off; and F2I of (A)2T does not reach its pre-arc I2T, cannot be damaged; therefore, fault selective removal during direct-current short circuit of the frequency converter is realized;
i due to a second short-circuit condition2The discharge circuit of (2) is longer, the short-circuit current is smaller, and the situation is more moderate than the first situation, so that the first situation can be considered to cover the second situation, and therefore, the response capability of the fuse to the short-circuit current is analyzed in the case of the direct-current short circuit outside the capacitor of the frequency converter.
In order to verify the reliability of the selective fault removal, a simulation modeling analysis method for analyzing the response capability of the fuse in the frequency converter of the direct current power system to the short-circuit current is provided below, which is used for calculating the I of the fuse 32 of each device in the direct current power system when the frequency converter 31 generates the direct current short circuit2T。
When short-circuit occurs, the power electronic switch connecting the two sections of direct current buses can be tripped within 15-25 mu s, the two connected direct current buses are separated, the interaction of the two sections of direct current buses within a very short time is ignored, and therefore, for direct current short-circuit analysis of the frequency converter, all equipment on a single section of direct current bus where the fault frequency converter is located only needs to be considered, and all equipment on the whole board does not need to be analyzed.
The simulation modeling analysis method for analyzing the response capability of the fuse in the frequency converter of the direct-current power system to the short-circuit current comprises the following specific steps;
1. establishing a cabinet model, taking the establishment of a main push cabinet M1 as an example, as shown in FIG. 4, modeling a capacitor C formed by a frequency converter thereinM1And its equivalent direct current resistance RESRcSeries connection of models, fusing of two sets of dc buses connected respectively at the input and output sides of the frequency converterThe fuse of each group of direct current buses comprises two fuse monomers which are arranged in parallel, the fuse monomers are modeled into resistors, and cables or copper bars between the input side and the output side of the frequency converter and the fuses are marked as CO 1; cables or copper bars from the two groups of fuses to the direct current busbar are marked as CO 2; the copper bar on the direct current bus is marked as CO3 and consists of a positive group and a negative group; the single cables or copper bars CO1 and CO2 are simplified into a model of series connection of resistors and inductors (because the specifications of the cables or copper bars CO1 and the cables or copper bars CO2 are small, parallel capacitors can be ignored under the condition of short circuit), the single copper bar CO3 is simplified into a model of series connection of resistors and inductors, and the capacitor of the copper bar CO3 is simplified into an equivalent capacitor C arranged between a positive direct current bus and a negative direct current busint(because in the case of a short circuit, the shunt capacitance is negligible); calculating to obtain specific parameters of the cabinet body model; the specific calculation is as follows:
(a) calculating the equivalent direct current resistance through the steady-state direct current power consumption and the rated current of the fuse, and obtaining the following formula:
equivalent short-circuit resistance R of fuse in simulation model in short-circuit stateSCFuseModeling by adopting a mode of carrying out short-circuit test on the fuse and carrying out curve fitting after acquiring an actual fusing waveform of the fuse;
usually, a large amount of short-circuit current flows into the fuse, which causes the temperature of the fuse to rise rapidly, and the equivalent short-circuit resistance RSCFuseThe nonlinear increase along with the temperature rise is realized, in order to simulate the nonlinear fusing characteristic of the fuse more truly, short circuit test is carried out on the fuse, and the actual fusing waveform of the fuse is collected;
(b) see fig. 5,FIG. 6; calculating the values R of the resistance, the inductance and the capacitance formed by simplifying the copper barco1，Rco2，Rco3,，Lco1，Lco2，Lco3，cintThe calculation formula is as follows:
the calculation formula of the series resistance of the copper bar is as follows:
wherein: resistance value R, unit omega; resistivity ρ, unit: omega m2(ii)/m; length l of cable or copper bar, unit: m; sectional area a of the copper bar, unit: m is2；
As shown in fig. 6, if a cable is used, the dc inductance value is calculated by the following formula:
wherein: magnetic permeability mu in vacuum0Is a constant of 4 π × 10-7(ii) a The unit H/m; the central distance a of 2 round cables is unit m; radius r of the cableLThe unit m; length of single cable l, unit m;
as shown in fig. 7, the direct current inductance value of the copper bar is calculated by the following formula:
wherein: magnetic permeability mu in vacuum0Is a constant of 4 π × 10-7(ii) a The unit H/m; the average distance a between the positive copper bar and the negative copper bar; the unit m; the width b of the single-phase copper bar is calculated by overlapping the widths if the single-phase copper bar is a plurality of copper bars; the unit m; the height h of the copper bar; the unit m; the length l of the single-phase copper bar is unit m;
the capacitance calculation formula of the copper bar CO3 is as follows:
wherein epsilondiIs a capacitance constant with a value of 8.854 × 10-12F/m, wherein a is the average distance between the positive copper bar and the negative copper bar, m and b are the widths of the copper bars, m and h are the lengths of the single-phase copper bars, and m is the unit;
2. establishing a simplified circuit model of the cabinet body, as shown in fig. 8 and 9, removing a capacitor C between the positive and negative direct current busesM1And its equivalent direct current resistance RESRcThe external resistance is equivalent to a resistor RaThe capacitance C is removed between the positive and negative DC busesM1And its equivalent direct current resistance RESRcThe external inductor is equivalent to an inductor La(ii) a The resistances on the positive and negative direct current buses are equivalent to a resistance RbThe inductance on the positive and negative DC buses is equivalent to an inductance LbSo as to obtain the simplified model,
wherein:
3. establishing a system circuit model, and establishing an integral circuit model of the C-PP system including all cabinets by referring to the steps, as shown in FIG. 10;
4. MATLAB simulation calculation is used to obtain I of fuses in each internal frequency converter of a cabinet when direct current of one internal frequency converter of the cabinet is short-circuited2T；
Accumulation of current and time of the fault loop fuse reaches its fuse I quickly2T, thereforeCutting off a barrier circuit; if the current and time accumulation of all other non-fault loop fuses does not exceed the pre-arc I of the corresponding fuse when the fault loop is cut off2T, indicating that the non-faulty loop is not affected; if the current and time of the non-fault circuit fuse exceeds the pre-arc I of the corresponding fuse when the fault circuit is cut off2T, the fuse at the position needs to be replaced by a fuse I before the arc2T larger fuse.
The above-mentioned embodiments are merely illustrative of the principles and effects of the present invention, and some embodiments may be used, not restrictive; it should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the inventive concept of the present invention, and these changes and modifications belong to the protection scope of the present invention.
Claims (4)
1. A simulation modeling analysis method for analyzing the response capability of a fuse in a frequency converter of a direct current power system to a short-circuit current is specifically as follows;
1) building a cabinet model, for example, building a single cabinet, modeling a capacitor C formed by a frequency converter thereinM1And its equivalent direct current resistance RESRcThe fuse comprises a series model, two groups of fuses of direct current buses are respectively connected with the input side and the output side of a frequency converter, the fuses of each group of direct current buses comprise two fuse monomers which are arranged in parallel, the fuse monomers are modeled into a resistor, and cables or copper bars between the input side and the output side of the frequency converter and the fuses are marked as CO 1; cables or copper bars from the two groups of fuses to the direct current busbar are marked as CO 2; the copper bar on the direct current bus is marked as CO3 and consists of a positive group and a negative group; the single cables or copper bars CO1 and CO2 are simplified into a model of series connection of a resistor and an inductor, the single copper bar CO3 is simplified into a model of series connection of a resistor and an inductor, and the capacitor of the copper bar CO3 is simplified into an equivalent capacitor C arranged between a positive direct current bus and a negative direct current busint(ii) a Calculating to obtain specific parameters of the cabinet body model; the specific calculation is as follows:
(a) calculating the equivalent direct current resistance through the steady-state direct current power consumption and the rated current of the fuse, and obtaining the following formula:
wherein: pV FuseIs the steady state dc power consumption of the fuse;
is the square of the steady state dc current of the fuse; rFuseIs a steady state dc resistance;
equivalent short-circuit resistance R of fuse in simulation model in short-circuit stateSCFuseModeling by adopting a mode of carrying out short-circuit test on the fuse and carrying out curve fitting after acquiring an actual fusing waveform of the fuse;
(b) calculating the value R of the resistance and the direct current inductance formed by simplifying the cable or the copper barco1,Rco2,Rco3,Lco1,Lco2,Lco3Calculating the equivalent capacitance C of the copper bar CO3int(ii) a The value L of the direct current inductance formed by simplifying the calculation copper barco1,Lco2,Lco3The calculation formula of (2) is:
wherein: magnetic permeability mu in vacuum0Is a constant of 4 π × 10-7(ii) a The average distance a between the positive copper bar and the negative copper bar; the unit m; the width b of the single-phase copper bar is calculated by overlapping the widths if the single-phase copper bar is a plurality of copper bars; the unit m; the height h of the copper bar; the unit m; the length l of the single-phase copper bar is unit m;
2) establishing a cabinet simplified circuit model, and removing a capacitor C between the positive and negative direct current busesM1And its equivalent direct current resistance RESRcThe external resistance is equivalent to a resistance Ra, and a capacitor C is arranged between the positive and negative direct current busesM1And its equivalent direct current resistance RESRcThe external inductor is equivalent to an inductor La; the resistance on the positive and negative direct current buses is equivalent to a resistance Rb, and the inductance on the positive and negative direct current buses is equivalent to an inductance Lb, so that a simplified model is obtained, wherein:
3) establishing a system circuit model, and establishing an integral circuit model of the C-PP system including all cabinets by referring to the steps;
4) obtaining I of fuses in each internal frequency converter of a cabinet when direct current of the internal frequency converter of a cabinet is short-circuited by using MATLAB simulation calculation2T；
Accumulation of current and time of the fault loop fuse reaches its fuse I quickly2T, cutting off a fault loop; if the current and time accumulation of all other non-fault loop fuses does not exceed the pre-arc I of the corresponding fuse when the fault loop is cut off2T, indicating that the non-faulty loop is not affected; if the current and time of the non-fault circuit fuse exceeds the pre-arc I of the corresponding fuse when the fault circuit is cut off2T, the fuse at the position needs to be replaced by a fuse I before the arc2T larger fuse.
2. The simulation modeling analysis method for analyzing the response capability of the fuse in the frequency converter of the direct current power system to the short-circuit current according to claim 1, characterized in that: the numerical value R of the resistance into which the cable or the copper bar is simplified is calculatedco1,Rco2,Rco3The specific calculation formula is as follows:
wherein: resistance value R, unit omega; resistivity ρ, unit: omega m2(ii)/m; length l of cable or copper bar, unit: m; the sectional area A of the cable or the copper bar, unit: m is2。
3. The simulation modeling analysis method for analyzing the response capability of the fuse in the frequency converter of the direct current power system to the short-circuit current according to claim 2, characterized in that: the value L of the direct current inductance simplified by the calculation cableco1,Lco2,Lco3The calculation formula of (2) is:
wherein: magnetic permeability mu in vacuum0Is a constant of 4 π × 10-7(ii) a The unit H/m; the central distance a of 2 round cables is unit m; radius r of the cableLThe unit m; length of single cable l, unit m.
4. The simulation modeling analysis method for analyzing the response capability of the fuse in the frequency converter of the direct current power system to the short-circuit current according to claim 3, characterized in that: the calculation formula of the equivalent capacitance of the copper bar CO3 is as follows:
wherein epsilondiIs a capacitance constant with a value of 8.854 × 10-12F/m, a is the average distance between the positive copper bar and the negative copper bar, m and b are the widths of the copper bars, and m and h are the lengths of the single-phase copper bars and m.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010190391.3A CN111404128B (en) | 2020-03-18 | 2020-03-18 | Simulation modeling analysis method for analyzing response capability of fuse in frequency converter of direct-current power system to short-circuit current |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010190391.3A CN111404128B (en) | 2020-03-18 | 2020-03-18 | Simulation modeling analysis method for analyzing response capability of fuse in frequency converter of direct-current power system to short-circuit current |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111404128A CN111404128A (en) | 2020-07-10 |
| CN111404128B true CN111404128B (en) | 2021-03-16 |
Family
ID=71428901
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010190391.3A Active CN111404128B (en) | 2020-03-18 | 2020-03-18 | Simulation modeling analysis method for analyzing response capability of fuse in frequency converter of direct-current power system to short-circuit current |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111404128B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112615358A (en) * | 2020-12-22 | 2021-04-06 | 武汉船用电力推进装置研究所（中国船舶重工集团公司第七一二研究所） | Ship direct-current networking electric propulsion system and short-circuit fault rapid protection method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014147755A1 (en) * | 2013-03-19 | 2014-09-25 | 三菱電機株式会社 | Power converter |
| CN110504672A (en) * | 2019-09-06 | 2019-11-26 | 中国船舶重工集团公司第七0四研究所 | The design protection method of ship direct current synthesis electrical method system and system |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106505559A (en) * | 2016-11-25 | 2017-03-15 | 国家电网公司 | Distribution network reliability analysis method based on power supply zone |
| CN108599589A (en) * | 2018-06-20 | 2018-09-28 | 瑞纳智能设备股份有限公司 | A kind of isolated low power consumption power supply automatic switchover communication device |
-
2020
- 2020-03-18 CN CN202010190391.3A patent/CN111404128B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014147755A1 (en) * | 2013-03-19 | 2014-09-25 | 三菱電機株式会社 | Power converter |
| CN110504672A (en) * | 2019-09-06 | 2019-11-26 | 中国船舶重工集团公司第七0四研究所 | The design protection method of ship direct current synthesis electrical method system and system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111404128A (en) | 2020-07-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108475928B (en) | Inverter with grid disconnection point and insulation resistance measurement and method for measuring insulation resistance | |
| CN103269166A (en) | Frequency converter with pre-charging protection function | |
| CN107359688A (en) | The fault handling method and device of power supply unit | |
| CN116014681B (en) | Protection device and protection method of photovoltaic power generation system and photovoltaic power generation system | |
| KR102541790B1 (en) | High voltage battery cluster and overcurrent protection circuit and switch box of high voltage battery cluster | |
| CN112615358A (en) | Ship direct-current networking electric propulsion system and short-circuit fault rapid protection method | |
| JP2012023875A (en) | System interconnection inverter system | |
| CN111404128B (en) | Simulation modeling analysis method for analyzing response capability of fuse in frequency converter of direct-current power system to short-circuit current | |
| CN111337804A (en) | Multi-channel direct-current insulation resistance detection protection circuit and protection method | |
| CN107425704A (en) | Failure protection method for parallel operation of modular inverters and modular inverter | |
| CN108365600A (en) | The faulty line detection method of hybrid dc circuit breaker system and breaker closing | |
| CN108146261B (en) | Fault protection method and device for electric vehicle rapid charging station | |
| KR102151107B1 (en) | Protection and distribution board for energy storage system | |
| CN207976558U (en) | Pressure-resistant test system between a kind of DC voltage support capacitor terminal | |
| CN208028772U (en) | A kind of high-power converter soft starting circuit | |
| CN108519544A (en) | Pressure-resistant test system and test method between a kind of DC voltage support capacitor terminal | |
| CN112379173A (en) | Direct current-to-ground insulation impedance detection circuit and method for variable bus voltage | |
| CN114825937A (en) | Inverter, protection method for insulation failure of direct current side of inverter and photovoltaic system | |
| CN113629695A (en) | Ship direct-current integrated power system and short-circuit protection design method thereof | |
| CN102262217A (en) | Test method and device for verifying short-circuit withstanding time of lead-acid battery | |
| CN202840606U (en) | Power supply device with safety mechanisms | |
| CN214954009U (en) | Fault simulation device for direct current system of transformer substation | |
| CN217820765U (en) | Switching unit and DC insulation detection device | |
| CN2874787Y (en) | Serial battery with breaking protective switch | |
| CN216794615U (en) | Marine direct-current busbar system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address |
Address after: Plot 83-D, Development Zone, Xinwu District, Wuxi City, Jiangsu Province, 214000 Patentee after: China Shipbuilding Saisiyi (Wuxi) Electrical Technology Co.,Ltd. Country or region after: China Patentee after: China State Shipbuilding Corporation Fenxi Heavy Industry Co.,Ltd. Address before: 214000 saisiyi, plot 83-d, development zone, Xinwu District, Wuxi City, Jiangsu Province Patentee before: WUXI SILENT ELECTRIC SYSTEM (SES) TECHNOLOGY Co.,Ltd. Country or region before: China Patentee before: SHANXI FENXI HEAVY INDUSTRY Co.,Ltd. |
|
| CP03 | Change of name, title or address |