CN105811853A - Fault-tolerant control method for power converter of embedded type variable-frequency speed control system - Google Patents

Fault-tolerant control method for power converter of embedded type variable-frequency speed control system Download PDF

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Publication number
CN105811853A
CN105811853A CN201610171941.0A CN201610171941A CN105811853A CN 105811853 A CN105811853 A CN 105811853A CN 201610171941 A CN201610171941 A CN 201610171941A CN 105811853 A CN105811853 A CN 105811853A
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China
Prior art keywords
fault
tolerant
control
power converter
algorithm
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Pending
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CN201610171941.0A
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Chinese (zh)
Inventor
赵金
周德洪
李云华
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Huazhong University of Science and Technology
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Huazhong University of Science and Technology
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Priority to CN201610171941.0A priority Critical patent/CN105811853A/en
Publication of CN105811853A publication Critical patent/CN105811853A/en
Pending legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
    • H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
    • H02P27/06—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters
    • H02P27/08—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation
    • H02P27/085—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation wherein the PWM mode is adapted on the running conditions of the motor, e.g. the switching frequency
    • 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
    • H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
    • H02J9/04—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source
    • H02J9/06—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems
    • H02J9/062—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems for AC powered loads
    • 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
    • H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
    • H02J9/04—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source
    • H02J9/06—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems
    • H02J9/062—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems for AC powered loads
    • H02J9/063—Common neutral, e.g. AC input neutral line connected to AC output neutral line and DC middle point
    • 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
    • H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
    • H02J9/04—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source
    • H02J9/06—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems
    • H02J9/068—Electronic means for switching from one power supply to another power supply, e.g. to avoid parallel connection

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Supply And Distribution Of Alternating Current (AREA)
  • Inverter Devices (AREA)

Abstract

Te invention discloses a fault-tolerant control method for a power converter of an embedded type variable-frequency speed control system. The fault-tolerant control method comprises the steps of carrying out diagnosis on faults of the power converter by adopting a fault diagnosis module based on three-phase current and speed given signals sampled by a current sensor; finishing reconstructing of a hardware topological structure of the system; embedding a fault-tolerant control algorithm into a normal control algorithm; and enabling a normal control policy of the control policy of the system into a corresponding fault-tolerant control policy in a smooth transitional manner through the fault positioning information of the power converter so as to realize the smooth transition from the normal control algorithm to the fault-tolerant control algorithm after the variable-frequency speed control system is in fault. The method is suitable for open-circuit fault non-redundancy tolerance of the power tube of the converter of the three-phase variable-frequency speed control system; according to the method, redundant shunt-wound power tubes are not required, so that the fault-tolerant topological structure of the system is simplified, and the hardware cost of the system is lowered; and in addition, the performance of the system is controlled by controlling the capacitor voltage, so that the stability of the system is further ensured.

Description

A kind of insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method
Technical field
The invention belongs to the technical field of frequency control, particularly relate to a kind of insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method.
Background technology
In recent years, the three-phase inverter being made up of all-controlling power electronics device, due to the existence of the problems such as power tube open circuit, their reliable rows aspect has certain risk, the performance of system is also easily thus subject to large effect, even at producing bigger loss in commercial Application.In order to improve the reliability of system, it is to avoid this loss, it is desirable to these power tube faults are had certain fault-tolerant ability by system.And these failure tolerants and reconfiguration system generate electricity by way of merging two or more grid systems in the regenerative resource such as tide energy, wind energy, and the system such as frequency control has wide practical use.
Numerous for the three-phase frequency-conversion speed-regulation system failure in the fault-tolerant prior art with reconfigurable control strategy, when frequency conversion speed-adjusting system is properly functioning and when faults-tolerant control runs, control strategy is often individually designed, this makes to need two set control programs when Fault-tolerant Control System Design, adds the expense of system resource；Meanwhile, system is difficult to seamlessly transit by normal system to fault-tolerant control system.
Summary of the invention
Disadvantages described above for prior art, the technical problem to be solved of the present invention is in that to provide a kind of insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method, realize high performance fault diagnosis and system reconfiguration, utilize quick fault diagnosis module to carry out system to detect in real time, utilize Embedded failure tolerant algorithm that system after mistake is controlled by the seamless switching of guarantee system and stablizing of performance.
The present invention provides a kind of insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method, comprises the following steps:
S1, utilize three-phase current and speed preset signal that current sensor samples, adopt fault diagnosis module that Power Converter faults is diagnosed；
S2, design corresponding power tube fault topology reconstruction circuit, fault diagnosis module is utilized to obtain Power Converter faults location information, turn on corresponding bidirectional thyristor, the correspondence of fault brachium pontis is connected to the electric capacity central point of DC side, the hardware topology reconstruct of completion system；
S3, by before fault with fault after frequency conversion speed-adjusting system carry out consistent modeling, design is normal controls the control module consistent with faults-tolerant control, ratio compared with normal control algolithm and tolerant fail algorithm, by control to capacitance voltage in fault-tolerant control algorithm, fault-tolerant control algorithm is embedded in normal control algolithm；
S4, utilize Power Converter faults location information, the control strategy of system is smoothly transitted into corresponding faults-tolerant control strategy by normal control strategy, to realize frequency conversion speed-adjusting system after fault occurs, by normal control algolithm taking over seamlessly to fault-tolerant control algorithm.
Further, described fault diagnosis module monitors when not breaking down, and system operates under normal finite aggregate predictive control algorithm；Described fault diagnosis module monitors when breaking down, and utilizes fault location information to switch on-off and make fault phase be connected to DC bus capacitor central point to update converter topology structure controlling nonredundancy；Fault brachium pontis is carried out Fault Isolation and is then controlled algorithm renewal by the fault location information that described control module utilizes fault diagnosis to feed back.
In general, by the contemplated above technical scheme of the present invention compared with prior art, have the advantages that
The insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method of the present invention is determined by the length L of periodic current signal array, calculates the variance Var of three current sample arrays, then calculates contra extent εx, relative variance ε according to gainedxDetermining whether that fault occurs, when there is single tube fault, then utilizing degree of bias γxDetermine whether the position of fault power pipe, improve the accuracy of the fault diagnosis of AC variable-frequency speed regulation system power inverter, and algorithm is simple, it is easy to accomplish.
Accompanying drawing explanation
Fig. 1 be the inventive method be suitable for the irredundant fault-tolerant frequency conversion speed-adjusting system of three-phase and basic block diagram.
Fig. 2 is the structured flowchart of the basic controlling of the inventive method.
Fig. 3 is the concrete control block diagram of the present invention.
Fig. 4 is the flow chart of the inventive method.
Detailed description of the invention
Describing the specific embodiment of the present invention in detail below in conjunction with accompanying drawing, it is as the part of this specification, by embodiment, principles of the invention is described, other aspects of the present invention, feature and advantage thereof will be become apparent from by this detailed description.In the accompanying drawing of institute's reference, in different figure, same or analogous parts use identical drawing reference numeral to represent.For making the present invention easier to understand, specific embodiments of the invention are further illustrated below.
As Figure 1-Figure 4, for the structural representation of the insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method of the present invention, wherein, Fig. 2 illustrates the basic control structure block diagram of the inventive method, and it specifically comprises the following steps that
1, all variablees are initialized.
2, biphase current i measured respectively by the current sensor in system (CT), voltage sensor (VT) and velocity sensora、ib, capacitance voltage vc1、vc2With motor speed ω.
3, according to the current information gathered, fault diagnosis module determines whether that changer open circuit fault occurs, and fault message is sent to control algolithm module.
4, when not having fault to occur, control module and adopt normal finite aggregate PREDICTIVE CONTROL scheme that motor is controlled.
5, when a failure occurs it, output switching signal is controlled to switch t by fault diagnosis module according to fault location informationatbtcBreak-make make fault phase be connected to DC bus capacitor central point, control module and according to fault location information, fault brachium pontis control to make its two power tubes be open-circuit condition.
6, control module and update control algolithm according to fault location information, be simultaneously introduced Embedded tolerant fail algorithm module, increase the control to capacitance voltage, to adapt to the topological structure after converting, complete the control to control object.
The present invention comprises fault diagnosis module and monitors in real time, and fault diagnosis positions and isolation, and system hardware reconstructs, and systematic control algorithm adapts to four steps.
First, system operates under normal topological structure, and now fault diagnosis module utilizes three-phase current that current sensor collects to carry out the monitoring of fault.
Secondly, when there is the power tube open circuit fault of changer, by fault diagnosis module by the malfunction monitoring of system out, fault location is then carried out, it is judged that the brachium pontis that fault occurs；
Then, the fault brachium pontis information according to location, fault brachium pontis is isolated, then sends system topology reconstruction signal, to system hardware topology reconstruction.
Finally, utilize the failure tolerant algorithm of insertion type, in conjunction with the information of fault location, System Fault Tolerance algorithm is incorporated in normal control algolithm, increase the control to capacitance voltage, it is ensured that stablizing of systematic function.
Subscript in the present invention represents sampling instant, and * represents set-point.Understanding in order to convenient, Fig. 3 illustrates the concrete control block diagram during a kind of this programme is implemented, and wherein broken box represents embeddable tolerant fail algorithm part.As shown in Figure 4, the insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method of the present invention, comprise the following steps:
S1, utilize three-phase current and speed preset signal that current sensor samples, adopt fault diagnosis module that Power Converter faults is diagnosed.
S2, design corresponding power tube fault topology reconstruction circuit, fault diagnosis module is utilized to obtain Power Converter faults location information, turn on corresponding bidirectional thyristor, the correspondence of fault brachium pontis is connected to the electric capacity central point of DC side, the hardware topology reconstruct of completion system.
S3, by before fault with fault after frequency conversion speed-adjusting system carry out consistent modeling, design is normal controls the control module consistent with faults-tolerant control, feature than compared with normal control algolithm and tolerant fail algorithm, find fault-tolerant control algorithm adds the control to capacitance voltage, utilize finite aggregate prediction torque control algorithm easily to add the feature of control object, fault-tolerant control algorithm is embedded in normal control algolithm.
S4, utilize Power Converter faults location information, the control strategy of system is smoothly transitted into corresponding faults-tolerant control strategy by normal control strategy, to realize frequency conversion speed-adjusting system after fault occurs, by normal control algolithm taking over seamlessly to fault-tolerant control algorithm.
Wherein, fault diagnosis module monitors when not breaking down, and system operates under normal finite aggregate predictive control algorithm；Fault diagnosis module monitors when breaking down, and utilizes fault location information to switch on-off and make fault phase be connected to DC bus capacitor central point to update converter topology structure controlling nonredundancy；Control module utilizes the fault location information that fault diagnosis is fed back that fault brachium pontis carries out Fault Isolation and is then controlled algorithm renewal.
The insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method of the present invention avoids and arranges redundant parallel power tube, simplify the Fault-Tolerant Topology structure of system, reduce the hardware cost of system, when there is changer open fault and control algolithm switches in the system that can also ensure that, performance is affected by little, and the method is fault-tolerant and reconfigurable control suitable in the three-phase frequency-conversion speed-regulation system failure.The method of the present invention instead of the method for the redundant power pipe arranging parallel connection in traditional scheme on changer, after power tube fault, fault phase is connected to DC capacitor voltage central point, the performance of system is controlled by controlling capacitance voltage, and then ensure that stablizing of system, can ensure that the stable performance of the uninterrupted operation of system and control object, the impact being subject to fault is little.

Claims (2)

1. an insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method, it is characterised in that comprise the following steps:
S1, utilize three-phase current and speed preset signal that current sensor samples, adopt fault diagnosis module that Power Converter faults is diagnosed；
S2, design corresponding power tube fault topology reconstruction circuit, fault diagnosis module is utilized to obtain Power Converter faults location information, turn on corresponding bidirectional thyristor, the correspondence of fault brachium pontis is connected to the electric capacity central point of DC side, the hardware topology reconstruct of completion system；
S3, by before fault with fault after frequency conversion speed-adjusting system carry out consistent modeling, design is normal controls the control module consistent with faults-tolerant control, ratio compared with normal control algolithm and tolerant fail algorithm, by control to capacitance voltage in fault-tolerant control algorithm, fault-tolerant control algorithm is embedded in normal control algolithm；
S4, utilize Power Converter faults location information, the control strategy of system is smoothly transitted into corresponding faults-tolerant control strategy by normal control strategy, to realize frequency conversion speed-adjusting system after fault occurs, by normal control algolithm taking over seamlessly to fault-tolerant control algorithm.
2. insertion type frequency conversion speed-adjusting system Power Converter faults fault tolerant control method according to claim 1, it is characterised in that described fault diagnosis module monitors when not breaking down, and system operates under normal finite aggregate predictive control algorithm；Described fault diagnosis module monitors when breaking down, and utilizes fault location information to switch on-off and make fault phase be connected to DC bus capacitor central point to update converter topology structure controlling nonredundancy；Fault brachium pontis is carried out Fault Isolation and is then controlled algorithm renewal by the fault location information that described control module utilizes fault diagnosis to feed back.
CN201610171941.0A 2016-03-23 2016-03-23 Fault-tolerant control method for power converter of embedded type variable-frequency speed control system Pending CN105811853A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107069771A (en) * 2016-12-23 2017-08-18 重庆大学 The method of LOAD FREQUENCY control of the multi-area Interconnected Power System based on failure tolerant
CN108649825A (en) * 2018-04-25 2018-10-12 上海海事大学 A kind of multiple faults partition method of cascade multilevel inverter
CN110149084A (en) * 2019-07-03 2019-08-20 河北工业大学 A kind of two-phase direct current generator driving system structure and open-circuit fault fault-tolerance approach
CN112305350A (en) * 2020-10-20 2021-02-02 云南电网有限责任公司电力科学研究院 Fault detection device for power module of frequency modulation test platform of new energy unit

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EP2562021A2 (en) * 2011-08-25 2013-02-27 Hamilton Sundstrand Corporation Regenerative load electric power management systems and methods
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CN204392129U (en) * 2015-02-07 2015-06-10 盐城工学院 A kind of error-tolerance type Instantaneous torque control asynchronous machine power generation system

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107069771A (en) * 2016-12-23 2017-08-18 重庆大学 The method of LOAD FREQUENCY control of the multi-area Interconnected Power System based on failure tolerant
CN107069771B (en) * 2016-12-23 2019-07-30 重庆大学 The method that multi-area Interconnected Power System is controlled based on the LOAD FREQUENCY of failure tolerant
CN108649825A (en) * 2018-04-25 2018-10-12 上海海事大学 A kind of multiple faults partition method of cascade multilevel inverter
CN110149084A (en) * 2019-07-03 2019-08-20 河北工业大学 A kind of two-phase direct current generator driving system structure and open-circuit fault fault-tolerance approach
CN110149084B (en) * 2019-07-03 2023-02-07 河北工业大学 Two-phase direct current motor driving system structure and open-circuit fault tolerance method
CN112305350A (en) * 2020-10-20 2021-02-02 云南电网有限责任公司电力科学研究院 Fault detection device for power module of frequency modulation test platform of new energy unit
CN112305350B (en) * 2020-10-20 2022-09-02 云南电网有限责任公司电力科学研究院 Fault detection device for power module of frequency modulation test platform of new energy unit

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Application publication date: 20160727