CN109980664B - Modulation degree equal amplitude redundancy control method based on zero sequence voltage injection - Google Patents
Modulation degree equal amplitude redundancy control method based on zero sequence voltage injection Download PDFInfo
- Publication number
- CN109980664B CN109980664B CN201910294982.2A CN201910294982A CN109980664B CN 109980664 B CN109980664 B CN 109980664B CN 201910294982 A CN201910294982 A CN 201910294982A CN 109980664 B CN109980664 B CN 109980664B
- Authority
- CN
- China
- Prior art keywords
- phase
- voltage
- zero sequence
- modulation degree
- sequence voltage
- 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
- 238000000034 method Methods 0.000 title claims abstract description 24
- 238000002347 injection Methods 0.000 title claims description 14
- 239000007924 injection Substances 0.000 title claims description 14
- 239000013598 vector Substances 0.000 claims description 8
- 238000004804 winding Methods 0.000 abstract description 9
- 230000008901 benefit Effects 0.000 abstract description 4
- 238000002955 isolation Methods 0.000 abstract description 3
- 238000011217 control strategy Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B19/00—Programme-control systems
- G05B19/02—Programme-control systems electric
- G05B19/04—Programme control other than numerical control, i.e. in sequence controllers or logic controllers
- G05B19/048—Monitoring; Safety
-
- 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
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/26—Arrangements for eliminating or reducing asymmetry in polyphase networks
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/50—Arrangements for eliminating or reducing asymmetry in polyphase networks
Abstract
When a ship high-voltage shore power supply system fails, zero sequence voltage is injected into three-phase voltage, the phase difference of the three-phase voltage is changed, and finally, line voltage symmetry among the three phases is realized. The zero sequence voltage can be obtained by making the modulation degree amplitude values of the three-phase voltages equal and calculating the corresponding mathematical operation. The ship shore power supply system comprises a multi-winding phase-shifting transformer, wherein the shore power grid voltage is divided into 3N groups of winding voltages with different phases through the multi-winding phase-shifting transformer, and N is the number of power module units; the multi-winding phase-shifting transformer is connected with a three-phase rectifier, 3N groups of winding voltages with different phases are rectified and then respectively used as direct current input signals of each group of H bridge units formed by power switch devices, and the direct current input signals are sequentially output through an inverter, a filter and an isolation transformer after being cascaded. The control method has the advantages of high fault tolerance, simple realization, low operation cost and high reliability.
Description
Technical Field
The invention belongs to the field of ship shore power, and relates to a modulation degree and other amplitude redundancy control method based on zero sequence voltage injection.
Background
When the ship is berthed to the wharf, the operation of all marine diesel engine power stations is stopped, and the ship power is supplied by the shore power station, so that the aims of improving the air quality, reducing the noise and the vibration of the port area are fulfilled, and meanwhile, the economic benefit is improved.
The shore power of the ship is suitable for the fields of ports, shipyards, floating docks, ocean drilling platforms and the like. At present, the redundant control strategy of the high-voltage shore power supply of the ship mostly adopts the traditional symmetrical bypass control and the traditional asymmetrical bypass control. And the symmetrical bypass control is that when a certain unit fails, the three-phase units at corresponding positions need to be bypassed, the phase voltages and the line voltages of the output three phases are symmetrical, and the derating operation is performed. The traditional asymmetric bypass control realizes the symmetry of the three-phase line voltage by changing the phase difference of the phase voltage under the condition that only the bypass unit fails, and outputs three-phase voltage higher than the traditional symmetric bypass voltage, the fault tolerance capability is higher than the traditional symmetric bypass control, the cost is low, but the modulation degree amplitude of the three-phase voltage output by the method is unequal.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a modulation degree and other amplitude redundancy control method based on zero sequence voltage injection, which has the advantages of higher fault tolerance than the traditional asymmetric bypass control, low cost and high reliability.
In order to achieve the above object, the modulation degree and other amplitude redundancy control method based on zero sequence voltage injection of the present invention comprises:
1) Judging whether a ship shore power supply system fails, if so, performing the operation of the step 2);
2) And injecting zero sequence voltage into the three-phase voltage, wherein the zero sequence voltage is obtained by performing mathematical operation on the modulation degree amplitude values of the three-phase voltage to be equal, and the phase difference of the three-phase voltage is changed to ensure that the line voltage between the three phases is symmetrical.
Step 1) if the ship shore power supply system does not fail, outputting three-phase voltage U OA ，U OB ，U OC The vectors of (2) are:
in the above, m a 、m b 、m c Modulation degrees corresponding to the A phase, the B phase and the C phase before failure; n is the number of sub-modules; u (U) dc Is the DC bus voltage.
After the step 2) is failed, if P modules of A phase are sent outGenerating faults, M modules of B phase are failed, Z modules of C phase are failed, and injecting zero sequence voltage U OO' Output three-phase voltage U' O'A ，U' O'B ，U' O'C The vectors of (2) are:
wherein ,
m 1 、m 2 、m 3 is a zero sequence voltage scaling factor.
The vectors of the output three-phase voltages after the occurrence of the fault are as follows:
the corresponding modulation degree after the fault is obtained by the method (3) is as follows:
in the above, m' a 、m' b 、m' c The modulation degrees corresponding to the A phase, the B phase and the C phase after the fault are adopted.
|m' a |、|m' b |、|m' c The I is modulation degree amplitude corresponding to A phase, B phase and C phase after failure, so that the I m 'is' a |＝|m' b |＝|m' c The value of P, M, Z of the fault number of each phase submodule is detected and determined, and the zero sequence voltage is calculated
Corresponding scaling factor m 1 、m 2 、m 3 。
A. The number P, M, Z of B, C phase failed modules satisfies the relation P+M+Z < N, and when all sub-modules fail, the output three-phase voltage will be 0, and the control method of the invention will not be adoptedIs applicable to. Modulation m 'corresponding to A phase, B phase and C phase after failure' a 、m' b 、m' c The unsaturated condition is satisfied, and when the modulation degree is saturated, the control strategy will fail.
Compared with the prior art, the invention has the following beneficial effects: the method is improved on the basis of the traditional asymmetric bypass control, when a ship high-voltage shore power supply system fails, zero sequence voltage is injected into three-phase voltages at first, the phase difference of the three-phase voltages is changed, and then the amplitude values of modulation degrees are equal, so that the output three-phase line voltages are symmetric, and the fault tolerance capacity is higher than that of the traditional asymmetric bypass control. The amplitude redundancy control method based on the modulation degree of zero sequence voltage injection and the like ensures the stable operation of the shore power supply device and the ship electric equipment, is simple to realize, and has the advantages of low cost and high reliability.
Drawings
FIG. 1 is a schematic diagram of a high-voltage shore power supply system of a ship;
FIG. 2 is a schematic diagram of the power unit structure of the high-voltage shore power supply system of the ship;
FIG. 3 is a zero sequence voltage vector diagram of a module fault injection of an A-phase high-voltage shore power supply of a ship;
FIG. 4 is a zero sequence voltage injection vector diagram before and after the failure of the high voltage shore power supply of the ship;
in fig. 1-2: 1-a multi-winding phase-shifting transformer; 2-a power unit integration cabinet; a 3-filter; 4-isolation transformers; 5-a switch cabinet; 6-direct current low-frequency capacitance; 7-a three-phase rectifier; an 8-H bridge unit; 9-controlling a protection system; 10-load.
In fig. 3 to 4: u (U) OA 、U OB 、U OC The three-phase voltages before failure are respectively; u (U) AB 、U BC 、U CA The voltages of the three phase lines before and after the fault are respectively; u's' O'A 、U' O'B 、U' O'C And the three-phase voltages after the faults are respectively.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
Referring to fig. 1-2, the invention discloses a ship shore power supply system, the whole system adopts a three-phase uncontrolled rectification + chain structure, shore power grid voltage is firstly divided into 3N groups of windings with different phases through a multi-winding phase-shifting transformer 1, and N is the number of power module units. Then 3N groups of winding voltages with different phases are rectified through a three-phase rectifier 7 and then used as direct current input signals of each group of H bridge units 8 formed by power switching devices respectively, three-phase voltages are output after being isolated through an inverter 8, an LC filter 3 and a transformer 4 after being cascaded, so that power supply to a load is realized, and a switch cabinet 5 is arranged between the isolation transformer 4 and the load 10.
The control method of the invention comprises the following steps: when the high-voltage shore power supply system of the ship fails, zero sequence voltage is injected into the three-phase voltage, and the phase difference of the three-phase voltage is changed, so that the line voltage between the three phases is symmetrical. The zero sequence voltage is obtained by equalizing modulation degree amplitude values of the three-phase voltages and corresponding mathematical operations, as shown in fig. 4.
The zero sequence voltage is calculated as follows:
before failure, three-phase voltage U is output OA ，U OB ，U OC As in formula (1), the three-phase voltages are symmetrical:
after the failure, if P modules of the A phase fail, M modules of the B phase fail, Z modules of the C phase fail, zero sequence voltage is injected, and three-phase voltage U 'is output' O'A ，U' O'B ，U' O'C The method comprises the following steps:
wherein ,
the three-phase voltage is obtained by the formulas (1) and (2), and after the fault occurs, the three-phase voltage is output as follows:
the modulation degree corresponding to the three-phase voltage after the fault can be obtained by the method (3):
let |m 'in the formula (4)' a |＝|m' b |＝|m' c The value of P, M, Z of the fault number of each phase submodule is detected and determined, and m can be calculated through corresponding mathematical operation 1 ，m 2 ，m 3 Thereby calculating the zero sequence voltage to be injected
In the above formulas (1), (2), (3), (4):
m a ，m b ，m c modulation degrees corresponding to the A phase, the B phase and the C phase before failure; n is the number of sub-modules; u (U) dc Is the voltage of a direct current bus; m is m 1 ，m 2 ，m 3 Is a zero sequence voltage proportionality coefficient; m's' a ，m' b ，m' c The modulation degree of the three-phase voltage after the fault is adopted.
Note that: the formula (4) satisfies the condition that P+M+Z is less than N and M' a ，m' b ，m' c The three-phase modulation degree is unsaturated.
The control method of the invention is compared with the traditional asymmetric zero sequence voltage injection control strategy as follows:
if the total number of modules per phase n=10, the individual modules of phase a fail.
1. The invention is based on the amplitude redundancy control strategy such as the modulation degree of zero sequence voltage injection;
as can be seen from fig. 3, the modulation degrees of the zero sequence voltage and the three-phase voltage injected after the fault are calculated as follows:
injecting zero sequence voltage three-phase voltage U 'after fault' O'A ，U' O'B ，U' O'C The amplitude of (2) is:
in the formula (5) |m' a |＝|m' b |＝|m' c |，|U OO' |＝m 1 |U OA Taking n=10, from equation (5): m is m 1 ＝0.0679。
The final injected zero sequence voltage is
Let m 1 ＝0.0679，m 2 ＝0，m 3 The value of the combination of the three-phase voltage modulation m 'after the fault is obtained by substituting 0 into the value of (4)' a ，m' b ，m' c The method comprises the following steps:
will be |m '' a |＝|m' b |＝|m' c Substituting I into (6) to obtain the modulation degree amplitude of the three-phase voltage as I m' a |＝|m' b |＝|m' c |＝1.0357|m a |；
2. Traditional asymmetric zero sequence voltage injection control;
as can be seen from fig. 3, the modulation degrees of the zero sequence voltage and the three-phase voltage injected after the fault are calculated as follows:
injecting zero sequence voltage three-phase voltage U 'after fault' O'A ，U' O'B ，U' O'C The method comprises the following steps:
wherein, will be
Substituting (7) to obtain a three-phase voltage modulation degree:
for (8) solving three-phase voltage modulation degree m' after fault " a ，m b "，m c The magnitude of "can be expressed as formula (9):
wherein ,|ma |＝|m b |＝|m c |。
The amplitude of the three-phase voltage modulation degree after the fault is obtained by the method (9) is as follows:
substituting n=10 into (10) to obtain the amplitude of the modulation degree of the three-phase voltage when the a phase fails to form a sub-module, wherein the amplitude is as follows:
in the formulae (5) to (11), m a ，m b ，m c Modulation degrees corresponding to the A phase, the B phase and the C phase before failure; n is the number of sub-modules; u (U) dc Is the voltage of a direct current bus; m is m 1 ，m 2 ，m 3 Is a zero sequence voltage proportionality coefficient; m's' a ，m' b ，m' c The modulation degree of the three-phase voltage, m' is the modulation degree of the three-phase voltage adopting amplitude redundancy control strategies such as the modulation degree based on zero sequence voltage injection after fault " a ，m b "，m c And the phase modulation degree is three-phase voltage modulation degree by adopting a traditional asymmetric zero sequence voltage injection control strategy after the fault.
Comparing the formula (5) with the formula (11), when the module fails, the modulation amplitude of the three-phase voltage obtained by the control method is smaller than that obtained by the traditional control method, and the modulation reaches larger margin of saturation, so that the control method has higher fault tolerance rate compared with the traditional control method.
The above description is only a preferred embodiment of the present invention and is not intended to limit the invention in any way, and it will be understood by those skilled in the art that the present invention may be modified and replaced without departing from the basic concept of the invention, and the modifications and substitutions fall within the scope of the appended claims.
Claims (1)
1. The modulation degree equal amplitude redundancy control method based on zero sequence voltage injection is characterized by comprising the following steps of:
1) Judging whether a ship shore power supply system fails, if so, performing the operation of the step 2);
2) Injecting zero sequence voltage into the three-phase voltage, wherein the zero sequence voltage is obtained by performing mathematical operation on the modulation degree amplitude values of the three-phase voltage to be equal, and the phase difference of the three-phase voltage is changed to ensure that the line voltage between the three phases is symmetrical;
in the step 1), if the ship shore power supply system does not fail, a three-phase voltage U is output OA ，U OB ，U OC The vectors of (2) are:
step 2) after the ship shore power system fails, if the A phase P modules fail, the B phase M modules fail, the C phase Z modules fail, and the zero sequence voltage U is injected OO' Output three-phase voltage U' O'A ，U' O'B ，U' O'C The vectors of (2) are:
wherein ,
in the formula ,ma 、m b 、m c Modulation degrees corresponding to the A phase, the B phase and the C phase before failure; n is the number of sub-modules; u (U) dc Is the voltage of a direct current bus; m is m 1 、m 2 、m 3 Is a zero sequence voltage proportionality coefficient;
the vectors of the output three-phase voltages after the occurrence of the fault are as follows:
the corresponding modulation degree after the fault is obtained by the method (3) is as follows:
in the formula ,m'a 、m' b 、m' c For the modulation degree corresponding to the A phase, the B phase and the C phase after the fault, the |m 'is formed' a |＝|m' b |＝|m' c I, wherein i m' a |、|m' b |、|m' c The I is modulation degree amplitude values corresponding to the A phase, the B phase and the C phase after the fault;
detecting and determining the value of P, M, Z of fault numbers of sub-modules of each phase, and calculating zero sequence voltage
Corresponding scaling factor m 1 、m 2 、m 3 Further calculate the modulation m 'corresponding to A phase, B phase and C phase after failure' a 、m' b 、m' c ；
A. The number P, M, Z of the modules with B, C phase faults satisfies the relation P+M+Z < N, and the modulation degrees M 'corresponding to the A phase, the B phase and the C phase after the faults' a 、m' b 、m' c The unsaturated condition is satisfied.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910294982.2A CN109980664B (en) | 2019-04-12 | 2019-04-12 | Modulation degree equal amplitude redundancy control method based on zero sequence voltage injection |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910294982.2A CN109980664B (en) | 2019-04-12 | 2019-04-12 | Modulation degree equal amplitude redundancy control method based on zero sequence voltage injection |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109980664A CN109980664A (en) | 2019-07-05 |
| CN109980664B true CN109980664B (en) | 2023-04-25 |
Family
ID=67084433
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910294982.2A Active CN109980664B (en) | 2019-04-12 | 2019-04-12 | Modulation degree equal amplitude redundancy control method based on zero sequence voltage injection |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109980664B (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104283219A (en) * | 2014-10-20 | 2015-01-14 | 中国矿业大学 | Voltage fluctuation restraining method for high-frequency zero-sequence voltage injection cascaded static synchronous compensator (STACOM) |
-
2019
- 2019-04-12 CN CN201910294982.2A patent/CN109980664B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104283219A (en) * | 2014-10-20 | 2015-01-14 | 中国矿业大学 | Voltage fluctuation restraining method for high-frequency zero-sequence voltage injection cascaded static synchronous compensator (STACOM) |
Non-Patent Citations (2)
| Title |
|---|
| 单相电压源整流器新型调制算法与控制策略的研究;毛乾锟;《电气应用》;20161231;第35卷(第13期);第34-40、57页 * |
| 基于零序电压注入的模块化多电平变流器故障容错控制;申科等;《电力系统自动化》;20140310(第05期);第96-102页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109980664A (en) | 2019-07-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5836412B2 (en) | Power converter | |
| Castellan et al. | A review of power electronics equipment for all-electric ship MVDC power systems | |
| JP5993675B2 (en) | Power converter, power conversion system, and control method for power converter | |
| WO2010116806A1 (en) | Power conversion device | |
| Lee et al. | Effect of a SFCL on commutation failure in a HVDC system | |
| CN107947146B (en) | Direct-current power grid based on modular multilevel converter and multilayer fault-tolerant control method | |
| KR20130095257A (en) | Hvdc converter comprising fullbridge cells for handling a dc side short circuit | |
| CN105324903A (en) | Methods and devices for controlling active power flow in a three-phase modular multilevel converter | |
| EP3387745A2 (en) | System and method for integrating energy storage into modular power converter | |
| US9461555B2 (en) | HVDC series current source converter | |
| WO2017138400A1 (en) | Power conversion device | |
| EP3007297B1 (en) | Multilevel converter for reactive power compensation | |
| CN105978040A (en) | Intelligent reverse power control system and control method for variable-frequency variable-voltage power supply | |
| EP3304710A1 (en) | Modular multilevel converter with cascaded h-bridges and phase-shifted transformer groups | |
| CN109980664B (en) | Modulation degree equal amplitude redundancy control method based on zero sequence voltage injection | |
| EP3236571B1 (en) | Cascaded h-bridge converter with multiphase transformer for reduction of harmonics | |
| CN102810856B (en) | Phase correction method for arbitrary impulse converter transformer current difference | |
| An et al. | A new DC multipulse integrated shipboard power supply system and performance analysis referring to transformer noninteger turns ratio deviation | |
| Lai et al. | A shunt-connected phase-shift transformer for shipboard harmonics eliminating rectifiers | |
| Oka et al. | Active front-end topology for 5 level medium voltage drive system with isolated DC bus | |
| Zhou et al. | Dual voltage DC generator for compact light-weight ship electrical systems | |
| Cheng et al. | Analysis of the commutation failure of inverters during open‐conductor faults at the AC side | |
| Wu et al. | A novel voltage balancing strategy for four-level hybrid-clamped converters under selective harmonic elimination PWM | |
| Babaei et al. | A new topology for interline dynamic voltage restorer based on direct three-phase converter | |
| Khaleghi et al. | Hardware-Based Fault-Tolerant Technique for Modular Multilevel Converter Based on Shifting Submodules between Legs |
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 |