CN113381429A - Flexible power supply device for rail transit and coordination control method - Google Patents

Flexible power supply device for rail transit and coordination control method Download PDF

Info

Publication number
CN113381429A
CN113381429A CN202110622325.3A CN202110622325A CN113381429A CN 113381429 A CN113381429 A CN 113381429A CN 202110622325 A CN202110622325 A CN 202110622325A CN 113381429 A CN113381429 A CN 113381429A
Authority
CN
China
Prior art keywords
converter
energy
current
regenerative braking
power
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.)
Granted
Application number
CN202110622325.3A
Other languages
Chinese (zh)
Other versions
CN113381429B (en
Inventor
陈民武
赖俊宏
程一林
代先锋
陈垠宇
陈天舒
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Southwest Jiaotong University
Original Assignee
Southwest Jiaotong University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Southwest Jiaotong University filed Critical Southwest Jiaotong University
Priority to CN202110622325.3A priority Critical patent/CN113381429B/en
Publication of CN113381429A publication Critical patent/CN113381429A/en
Application granted granted Critical
Publication of CN113381429B publication Critical patent/CN113381429B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • 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
    • H02J3/28—Arrangements for balancing of the load in a network by storage of energy
    • H02J3/32—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means
    • H02J3/322—Arrangements for balancing of the load in a network by storage of energy using batteries with converting means the battery being on-board an electric or hybrid vehicle, e.g. vehicle to grid arrangements [V2G], power aggregation, use of the battery for network load balancing, coordinated or cooperative battery charging
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L9/00—Electric propulsion with power supply external to the vehicle
    • 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
    • H02J5/00—Circuit arrangements for transfer of electric power between ac networks and dc networks
    • 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
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/14—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
    • H02J7/1423—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle with multiple batteries
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
    • H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
    • H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
    • H02M3/158—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/02—Conversion of ac power input into dc power output without possibility of reversal
    • H02M7/04—Conversion of ac power input into dc power output without possibility of reversal by static converters
    • H02M7/12—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/21—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M7/217—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M7/219—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only in a bridge configuration

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Inverter Devices (AREA)

Abstract

The invention discloses a flexible power supply device for rail transit and a coordination control method, which are used for respectively acquiring the voltage and the current of a load at an outlet of a substation at two sides of alternating current and direct current, calculating to obtain the instantaneous power of the load and obtaining the system working condition under a corresponding mode; the power value of each link, such as the power transmitted from the alternating-current side contact network to the intermediate direct-current link, the power transmitted from the intermediate direct-current link to the direct-current side contact network, the power of the energy feedback system, the power of the hybrid energy storage unit and the like, is obtained; calculating a reference current for each converter based on each power; and obtaining the reference current of the AC side contact network converter, the reference current of the hybrid energy storage system unit converter, the reference current of the DC side contact network converter and the reference current of the energy feeding system side converter, and controlling each converter. The invention realizes the full utilization of regenerative braking energy, directly communicates the energy between the alternating current power supply and the direct current power supply, and has the advantages of convenience, safety, environmental friendliness, wide application range, high response speed and the like.

Description

Flexible power supply device for rail transit and coordination control method
Technical Field
The invention belongs to the technical field of rail transit power supply, and particularly relates to a rail transit flexible power supply device and a coordination control method.
Background
At present, an alternating-current and direct-current double-system urban rail transit traction power supply mode is still blank in China, represents the development direction of interconnection and intercommunication between an urban rail transit system and urban railways, and has a very wide application prospect. The key technology for researching AC and DC double-system traction power supply is not only a necessary core technology for completing production tasks at present, but also represents the key direction of future design market development, and has important engineering significance and market value.
Taking Chongqing river jumper as an example, the line is positioned in the southwest of Chongqing city, and the fifth line, the fifth branch line, the seventh line and the seventeen line of urban rail transit are respectively connected in series from east to west, and are important components for planning suburb railway line networks in Chongqing city. In order to realize the through operation with the track traffic five line of the Chongqing, the engineering traction power supply mode adopts an alternating current and direct current double-mode power supply mode. The jump-pedal to middle beam mountain tunnel section connected with the fifth line is powered by a DC 1500V system and is connected with the fifth line of urban rail transit, and can continue to extend to be connected with other rail transit lines in the urban area in a long term. The AC 25kV system is adopted to supply power in the direction from the outside of the urban area to Jiangjin, and the condition of connection with the urban main line railway in a long term is reserved. The power supply scheme not only gives full play to respective advantages of alternating current and direct current traction power supply modes, but also realizes seamless connection between the urban common-speed rail transit line and the urban rail transit express line, greatly improves the rail transit service level, and is the direction of urban rail transit development in the future.
In urban rail transit, due to the short station spacing, the train is started and braked frequently, and the braking energy is considerable from the perspective of energy interchange. The application of technologies such as storage battery energy storage, super capacitor energy storage, flywheel energy storage and the like in the field of rail transit has been widely researched, but a ground regenerative braking energy utilization system applied to a double-current system traction power supply system is still blank, and because a double-current system circuit has split-phase sections of a direct-current system and an alternating-current system, energy between the direct-current circuit and the alternating-current circuit cannot be directly transmitted, so that regenerative braking energy on one side cannot be utilized by the other side.
In summary, how to effectively utilize the regenerative braking energy generated by the dual-current line and provide an energy interconnection channel for the ac line and the dc line is a technical problem to be solved in the field.
Disclosure of Invention
In order to solve the problems, the invention provides a flexible power supply device for rail transit and a coordination control method, which are suitable for a dual-system traction power supply system, can be installed between an alternating-current traction power supply system and a direct-current traction power supply system, realize the full utilization of regenerative braking energy, directly communicate the energy between an alternating-current line and a direct-current line, and have the advantages of convenience, safety, environmental friendliness, wide application range, high response speed and the like.
In order to achieve the purpose, the invention adopts the technical scheme that: a rail transit flexible power supply coordination control method comprises the following steps:
s10, respectively collecting voltage and current of a load at outlets of the power substations on the two sides of the alternating current and the direct current, and calculating to obtain instantaneous power of the load;
s20, according to the load instantaneous power, based on the system working mode division, judging the working mode of the system at the moment, and obtaining the system working condition under the corresponding mode;
s30, based on the system working condition, obtaining the power transmitted from the AC side contact network to the intermediate DC link, the power transmitted from the intermediate DC link to the DC side contact network, the power transmitted from the intermediate DC link to the energy feedback system, and the power transmitted from the intermediate DC link to the hybrid energy storage unit;
s40, calculating a reference current of each converter from the voltage value of the connected device of each converter based on each power acquired in step S30; obtaining a reference current of an alternating current side contact network converter, a reference current of a direct current side contact network converter, a reference current of a hybrid energy storage unit converter and a reference current of an energy feed system converter;
s50, the inverters are controlled based on the reference signals obtained in step S40.
Further, according to the load instantaneous power PL-ACAnd PL-DCJudging the working mode of the system at the moment based on the system working mode division; according to the instantaneous power P of the loadL-ACAnd PL-DCBased on a valley fill threshold value P preset for the AC side transformationLow-ACPeak clipping threshold value PH-ACA valley fill threshold value P preset for DC side transformationLow-DCPeak clipping threshold value PH-DCMaximum charge and discharge power P of hybrid energy storage unitHESS-maxAnd the maximum power P absorbable by the energy feedback systemEFS-maxJudging the system working condition at the moment; the method comprises the following steps:
a: when P is presentL-AC< 0 and PL-DCWhen the voltage is less than 0, the system is in a regenerative braking mode, and the regenerative braking energy of the contact network at the alternating current side is transmitted to the intermediate direct current link through the single-phase AC-DC converter; the regenerative braking energy of the direct-current side contact network is transmitted to the intermediate direct-current link through the first DC-DC converter;
a1)|PL-AC+PL-DC|＜PEFS-maxthe energy feedback system absorbs the regenerative braking energy transmitted to the middle direct current link by the lines on two sides through the three-phase AC-DC converter as a working condition 1;
a2)PEFS-max＜|PL-AC+PL-DC|＜PHESS-max+PEFS-maxif the regenerative braking energy of the lines on the two sides cannot be completely absorbed by the energy feeding system, the hybrid energy storage unit participates in absorbing the part of the regenerative braking energy as a working condition 2;
a3)PHESS-max+PEFS-max＜|PL-AC+PL-DCif the hybrid energy storage unit reaches the maximum charging power and the unabsorbed regenerative braking energy exists at the moment, the energy on the alternating current side is transmitted to a power grid connected with a traction substation in a reverse mode, and the part of energy on the direct current side is dissipated in a heat energy mode to serve as a working condition 3;
b: when P is presentL-AC> 0 and PL-DCWhen the speed is higher than 0, the system is in a traction mode;
b1) when P is presentH-AC＜PL-AC，PH-DC＜PL-DCDuring the operation, the energy storage components of the hybrid energy storage unit are subjected to peak clipping at two sides according to a proportion respectively, and the operation condition is set as a working condition 4;
b2) when P is presentH-AC＜PL-AC,PL-AC-PHESS-max＜PH-AC,PLow-DC＜PL-DC＜PH-DCDuring operation, the hybrid energy storage unit performs peak clipping on the alternating current side, and the working condition is set as 5;
b3) when P is presentH-AC＜PL-AC,PH-AC＜PL-AC-PHESS-max,PLow-DC＜PL-DC＜PH-DCWhen the working condition is 6, the peak clipping capacity of the hybrid energy storage unit is insufficient, and the direct current side is the alternating current side for clipping the peak;
b4) when P is presentLow-AC＜PL-AC＜PH-AC,PH-DC＜PL-DC,PL-DC-PHESS-max＜PH-DCDuring operation, the hybrid energy storage unit performs peak clipping on the direct current side as a working condition 7;
b5) when P is presentLow-AC＜PL-AC＜PH-AC,PH-DC＜PL-DC,PH-DC＜PL-DC-PHESS-maxWhen the working condition is 8, the peak clipping capacity of the hybrid energy storage unit is insufficient, and the alternating current side is the alternating current side for clipping the peak;
b6) when P is presentLow-AC＜PL-AC＜PH-AC,PLow-DC＜PL-DC＜PH-DCWhen the hybrid energy storage unit is in operation, the hybrid energy storage unit does not work, and energy is not exchanged at two sides of the hybrid energy storage unit as a working condition 9;
b7) when P is presentLow-AC＜PL-AC＜PH-AC,0＜PL-DC＜PLow-DCIn the process, the hybrid energy storage unit is subjected to direct-current side valley filling and serves as a working condition 10;
b9) when P is presentLow-DC＜PL-DC＜PH-DC,0＜PL-AC＜PLow-ACDuring operation, the hybrid energy storage unit is subjected to alternating-current side valley filling and serves as a working condition 11;
b10) when 0 < PL-AC＜PLow-AC,0＜PL-DC＜PLow-DCWhen the hybrid energy storage unit is used, filling the valleys at two sides according to a proportion, and taking the filled valleys as a working condition 12;
c: when P is presentL-AC< 0 and PL-DCWhen the voltage is higher than 0, the system is in an energy transmission mode;
c1) when P is presentL-AC＜0,PL-DC-|PL-AC|＜PH-DCIn the process, the regenerative braking energy generated at the alternating current side is transferred to the direct current side to be fully utilized as a working condition 13;
c2) when P is presentL-AC＜0,0＜|PL-AC|-PL-DC＜PEFS-maxWhen the energy is used, all the energy on the direct current side is derived from the regenerative braking energy on the alternating current side, and the extra regenerative braking energy is absorbed by the energy feedback system to serve as a working condition 14;
c3) when P is presentL-AC＜0,PEFS-max＜|PL-AC|-PL-DC＜PHESS-max+PEFS-maxWhen the energy is used, all the energy on the direct current side is derived from the regenerative braking energy on the alternating current side, the energy feedback system absorbs the regenerative braking energy with the maximum power, and the extra regenerative braking energy is absorbed by the hybrid energy storage device to serve as the working condition 15;
c4) when P is presentL-AC＜0,PHESS-max+PEFS-max＜|PL-AC|-PL-DCWhen the energy is used, all the energy on the direct current side is derived from the regenerative braking energy on the alternating current side, the energy feedback system and the hybrid energy storage device absorb the regenerative braking energy with the maximum power, and the extra regenerative braking energy returns to the power grid as a working condition 16;
c5) when P is presentL-AC＜0,PH-DC＜PL-DC-|PL-ACWhen the voltage is lower than the threshold voltage, the hybrid energy storage unit performs peak clipping on the direct current side, and the regenerative braking energy generated on the alternating current side is also transmitted to the direct current sidePerforming peak clipping as working condition 17;
when P is presentL-AC> 0 and PL-DCWhen the frequency is less than 0, the system is in an energy transmission mode;
c6) when P is presentL-DC＜0,0＜PL-AC-|PL-DC|＜PH-ACIn the process, the regenerative braking energy generated by the direct current side is transferred to the alternating current side to be fully utilized as the working condition 18;
c7) when P is presentL-DC＜0,0＜|PL-DC|-PL-AC＜PEFS-maxWhen the energy is used, all the energy on the alternating current side comes from the regenerative braking energy on the direct current side, and the extra regenerative braking energy is absorbed by the energy feedback system to serve as a working condition 19;
c8) when P is presentL-DC＜0,PEFS-max＜|PL-DC|-PL-AC＜PHESS-max+PEFS-maxWhen the energy is used, all the energy on the alternating current side comes from the regenerative braking energy on the direct current side, the energy feedback system absorbs the regenerative braking energy with the maximum power, and the extra regenerative braking energy is absorbed by the hybrid energy storage device to serve as the working condition 20;
c9) when P is presentL-DC＜0,PHESS-max+PEFS-max＜|PL-DC|-PL-ACWhen the energy is used, all the energy on the alternating current side is derived from the regenerative braking energy on the direct current side, the energy feedback system and the hybrid energy storage device absorb the regenerative braking energy with the maximum power, and the extra regenerative braking energy is dissipated in a heat energy form to be used as a working condition 21;
c10) when P is presentL-DC＜0,PH-AC＜PL-AC-|PL-DCWhen the voltage is lower than the preset voltage, the hybrid energy storage unit is used for alternating current side peak clipping, and the regenerative braking energy generated by the direct current side is also transmitted to the alternating current side for peak clipping to serve as a working condition 22.
Further, in step S30, based on the system condition at this time, the power P transmitted by the ac side contact network and the intermediate dc linkMidDC-DCThe power P of the intermediate DC link transmission and the DC side contact networkMidDC-DCPower P of intermediate DC link transmission and energy feedback systemMidDC-FAnd the power P of the intermediate direct current link transmission and hybrid energy storage unitHESS；
Will PHESSThe low-frequency component is transmitted as an intermediate direct current link and the power P of the storage battery through a low-pass filterMidDC-Bat，PHESS-PMidDC-BatPower P as intermediate DC link transmission and super capacitorMidDC-SC。
Further, in step S30, calculating each power value based on the system operating condition at the time includes:
in condition 1:
Figure BDA0003100361090000051
in condition 2:
Figure BDA0003100361090000052
in condition 3:
Figure BDA0003100361090000053
in condition 4:
Figure BDA0003100361090000054
in condition 5:
Figure BDA0003100361090000055
in condition 6:
Figure BDA0003100361090000056
in condition 7:
Figure BDA0003100361090000061
in condition 8:
Figure BDA0003100361090000062
in operating condition 9:
Figure BDA0003100361090000063
in condition 10:
Figure BDA0003100361090000064
in operating condition 11:
Figure BDA0003100361090000065
in operating condition 12:
Figure BDA0003100361090000066
in operating condition 13:
Figure BDA0003100361090000067
in condition 14:
Figure BDA0003100361090000071
in operating condition 15:
Figure BDA0003100361090000072
in condition 16:
Figure BDA0003100361090000073
in operating condition 17:
Figure BDA0003100361090000074
in condition 18:
Figure BDA0003100361090000075
in condition 19:
Figure BDA0003100361090000076
in operating condition 20:
Figure BDA0003100361090000077
in operating condition 21:
Figure BDA0003100361090000078
in operating condition 22:
Figure BDA0003100361090000081
further, in step S40, the reference current of the AC-side contact grid converter is IACrefThe reference current of the direct current side contact network converter is the reference current of the first DC-DC converter and is iDCrefThe reference current of the intermediate direct-current link converter comprises the reference current of the second DC-DC converter and is iBATrefAnd the reference current of the third DC-DC converter is iSCrefThe reference current of the energy-fed system side converter is the reference current of the three-phase AC-DC converter and is iFref；
Reference current I of single-phase AC-DC converterACrefReference current i of the first DC-DC converterDCrefReference current i of the second DC-DC converterBATrefReference current i of the third DC-DC converterSCrefReference current i of three-phase AC-DC converterFrefThe calculation formula is as follows:
Figure BDA0003100361090000082
wherein, VACIs an effective value of the AC side voltage, k1For ac side transformer transformation ratio, VDCIs an effective value of the DC side voltage, VBATIs the battery voltage, VSCIs a super capacitor voltage, VEFSTo be able to feed the system voltage, k2The transformation ratio of the system transformer is fed.
Further, in step S50, when controlling each inverter based on each reference signal obtained in step S40: and (3) single-phase AC-DC converter voltage outer ring prediction current inner ring double-ring control: the voltage reference value u of the intermediate direct current link is compareddc-refAnd the actual value udcSubtracting the input signal from the input signal to form a PI controller, forming a voltage outer loop control, and adding IACrefAnd obtaining a switching signal for controlling the single-phase AC-DC converter through predictive current control and PWM modulation.
Further, in step S50, the first DC-DC converter, the second DC-DC converter, and the third DC-DC converter are PI-controlled when the converters are controlled based on the reference signals obtained in step S40: from a reference current iDCref、iBATref、iSCrefRespectively with the actual value i of the direct current side currentDCActual value i of current of storage battery in hybrid energy storage unitBATActual value i of super capacitor current in hybrid energy storage unitSCAnd obtaining switching signals for controlling the first DC-DC converter, the second DC-DC converter and the third DC-DC converter through PI control and a hysteresis comparator.
Further, in step S50, when controlling each inverter based on each reference signal obtained in step S40: the three-phase AC-DC converter adopts dq decoupling control: from a reference current iFrefAnd the actual values of the three-phase voltage and the three-phase current of the energy feedback system are subjected to park transformation and park inverse transformation to complete decoupling control, and then a switching signal for controlling the three-phase AC-DC converter is obtained through PWM modulation.
On the other hand, the invention also provides a flexible power supply device for rail transit, which comprises a step-down transformer, a single-phase AC-DC converter, a direct-current voltage-stabilizing capacitor, a first DC-DC converter, a second DC-DC converter, a third DC-DC converter, a super capacitor, a storage battery, a three-phase AC-DC converter and an LCL filter circuit, wherein the step-down transformer is connected with the single-phase AC-DC converter; the input end of the step-down transformer is connected with an alternating current side contact network, and the output end of the step-down transformer is connected with the single-phase AC-DC converter; the output end of the single-phase AC-DC converter is connected with a direct-current voltage-stabilizing capacitor, a first DC-DC converter, a second DC-DC converter, a third DC-DC converter and a three-phase AC-DC converter in parallel; the other end of the first DC-DC converter is connected with a direct current side contact network; the output end of the second DC-DC converter is connected with the super capacitor, and the output end of the third DC-DC converter is connected with the storage battery to form a hybrid energy storage unit; and the output end of the three-phase AC-DC converter is connected with the LCL filter circuit and then is connected to the energy feed system.
Further, the single-phase AC-DC converter adopts a two-level H-bridge topology, a cascade H-bridge topology or an MMC topology; the first DC-DC converter, the second DC-DC converter and the third DC-DC converter adopt bidirectional Buck-Boost converters, and the output side of the bidirectional Buck-Boost converters is connected with a filter inductor; the three-phase AC-DC converter adopts a two-level three-bridge-arm H-bridge topology.
The beneficial effects of the technical scheme are as follows:
the method comprises the steps of respectively collecting voltage and current data of loads at outlets of an alternating-current side substation and a direct-current side substation, judging operating conditions at two sides of a system, and dividing 3 working modes; and comparing the power of the substations on the two sides with a peak clipping threshold, a valley filling threshold, the maximum charge-discharge power of the hybrid energy storage device and the maximum load power of the energy feeding system respectively, refining 22 specific conditions under 3 working modes, and setting a power value required to be transmitted by each converter and a corresponding current reference value thereof. In the regenerative braking mode, regenerative braking energy can be supplied to a 10kV load and stored in the hybrid energy storage device; in a traction mode, the hybrid energy storage device is used for peak clipping and valley filling of a substation on an alternating current side and a direct current side; in the energy transmission mode, energy can be directly transmitted between the AC side and the DC side, and the near utilization of regenerative braking energy is realized. The track traffic flexible power supply device and the coordination control method realize the full utilization of regenerative braking energy, effectively reduce the electric charge, directly communicate the energy between the alternating current line and the direct current line, and have the advantages of convenience, safety, environmental friendliness, wide application range, high response speed and the like.
The invention effectively utilizes the energy storage system to recover and reuse the regenerative braking energy generated by the train and improves the utilization rate of the regenerative braking energy. The invention utilizes the energy storage system and the converter to carry out peak clipping on the peak load, and can supply power to the power system by the energy feed system, thereby achieving the effect of effectively reducing the electric charge. The invention provides an energy transmission channel for an alternating current side and a direct current side which are originally isolated from each other by utilizing the single-phase AC-DC converter and the DC-DC converter, realizes the interconnection of energy between two systems and achieves the aim of efficiently utilizing regenerative braking energy.
Drawings
Fig. 1 is a schematic flow chart of a flexible power supply coordination control method for rail transit according to the present invention;
FIG. 2 is a flow chart of the division of the working modes and the division of each specific working condition in the embodiment of the present invention;
FIG. 3 is a block diagram of a double-loop control strategy of an inner loop and an outer loop of a voltage outer loop of the single-phase AC-DC converter in the embodiment of the present invention;
FIG. 4 is a block diagram of a PI control strategy of the DC-DC converter in an embodiment of the present invention;
FIG. 5 is a block diagram of a dq decoupling control strategy for a three-phase AC-DC converter in an embodiment of the invention;
fig. 6 is a schematic structural diagram of a rail transit flexible power supply device according to an embodiment of the present invention;
FIG. 7 is a schematic diagram of a dual-current system traction power supply system and its electrically isolated phase (no-battery) in accordance with an embodiment of the present invention;
fig. 8 is a simulation waveform diagram of DC link voltage, AC side current, DC side current, a feedable a-phase current, single-phase AC-DC converter power factor, and hybrid energy storage device power under typical conditions in an embodiment of the present invention.
The power supply comprises a step-down transformer 1, a single-phase AC-DC converter 2, a direct-current voltage-stabilizing capacitor 3, a first DC-DC converter 4, a second DC-DC converter 5, a third DC-DC converter 6, a super capacitor 7, a storage battery 8, a three-phase AC-DC converter 9 and an LCL filter circuit 10.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described with reference to the accompanying drawings.
In this embodiment, referring to fig. 1, the present invention provides a flexible power supply coordination control method for rail transit, including the steps of:
s10, respectively collecting voltage and current of a load at outlets of the power substations on the two sides of the alternating current and the direct current, and calculating to obtain instantaneous power of the load;
s20, according to the load instantaneous power, based on the system working mode division, judging the working mode of the system at the moment, and obtaining the system working condition under the corresponding mode;
s30, based on the system working condition, obtaining the power transmitted from the AC side contact network to the intermediate DC link, the power transmitted from the intermediate DC link to the DC side contact network, the power transmitted from the intermediate DC link to the energy feedback system, and the power transmitted from the intermediate DC link to the hybrid energy storage unit;
s40, calculating a reference current of each converter from the voltage value of the connected device of each converter based on each power acquired in step S30; obtaining a reference current of an alternating current side contact network converter, a reference current of a direct current side contact network converter, a reference current of a hybrid energy storage unit converter and a reference current of an energy feed system converter;
s50, the inverters are controlled based on the reference signals obtained in step S40.
As an optimization scheme of the above embodiment, as shown in FIG. 2, the instantaneous power P is determined according to the loadL-ACAnd PL-DCJudging the working mode of the system at the moment based on the system working mode division; according to the instantaneous power P of the loadL-ACAnd PL-DCBased on a valley fill threshold value P preset for the AC side transformationLow-ACPeak clipping threshold value PH-ACA valley fill threshold value P preset for DC side transformationLow-DCPeak clipping threshold value PH-DCMaximum charge and discharge power P of hybrid energy storage unitHESS-maxAnd the maximum power P absorbable by the energy feedback systemEFS-maxJudging the system working condition at the moment; the method comprises the following steps:
a: when P is presentL-AC< 0 and PL-DCWhen the voltage is less than 0, the system is in a regenerative braking mode, and the regenerative braking energy of the contact network at the alternating current side is transmitted to the intermediate direct current link through the single-phase AC-DC converter; the regenerative braking energy of the direct-current side contact network is transmitted to the intermediate direct-current link through the first DC-DC converter;
a1)|PL-AC+PL-DC|＜PEFS-maxthe energy feed system absorbs the transmission of two side lines to the middle direct current through the three-phase AC-DC converterThe regenerative braking energy of the link is taken as working condition 1;
a2)PEFS-max＜|PL-AC+PL-DC|＜PHESS-max+PEFS-maxif the regenerative braking energy of the lines on the two sides cannot be completely absorbed by the energy feeding system, the hybrid energy storage unit participates in absorbing the part of the regenerative braking energy as a working condition 2;
a3)PHESS-max+PEFS-max＜|PL-AC+PL-DCif the hybrid energy storage unit reaches the maximum charging power and the unabsorbed regenerative braking energy exists at the moment, the energy on the alternating current side is transmitted to a power grid connected with a traction substation in a reverse mode, and the part of energy on the direct current side is dissipated in a heat energy mode to serve as a working condition 3;
b: when P is presentL-AC> 0 and PL-DCWhen the speed is higher than 0, the system is in a traction mode;
b1) when P is presentH-AC＜PL-AC，PH-DC＜PL-DCDuring the operation, the energy storage components of the hybrid energy storage unit are subjected to peak clipping at two sides according to a proportion respectively, and the operation condition is set as a working condition 4;
b2) when P is presentH-AC＜PL-AC,PL-AC-PHESS-max＜PH-AC,PLow-DC＜PL-DC＜PH-DCDuring operation, the hybrid energy storage unit performs peak clipping on the alternating current side, and the working condition is set as 5;
b3) when P is presentH-AC＜PL-AC,PH-AC＜PL-AC-PHESS-max,PLow-DC＜PL-DC＜PH-DCWhen the working condition is 6, the peak clipping capacity of the hybrid energy storage unit is insufficient, and the direct current side is the alternating current side for clipping the peak;
b4) when P is presentLow-AC＜PL-AC＜PH-AC,PH-DC＜PL-DC,PL-DC-PHESS-max＜PH-DCDuring operation, the hybrid energy storage unit performs peak clipping on the direct current side as a working condition 7;
b5) when P is presentLow-AC＜PL-AC＜PH-AC,PH-DC＜PL-DC,PH-DC＜PL-DC-PHESS-maxThe peak clipping capability of the hybrid energy storage unit is not sufficientThe AC side is the AC side peak clipping and is taken as the working condition 8;
b6) when P is presentLow-AC＜PL-AC＜PH-AC,PLow-DC＜PL-DC＜PH-DCWhen the hybrid energy storage unit is in operation, the hybrid energy storage unit does not work, and energy is not exchanged at two sides of the hybrid energy storage unit as a working condition 9;
b7) when P is presentLow-AC＜PL-AC＜PH-AC,0＜PL-DC＜PLow-DCIn the process, the hybrid energy storage unit is subjected to direct-current side valley filling and serves as a working condition 10;
b9) when P is presentLow-DC＜PL-DC＜PH-DC,0＜PL-AC＜PLow-ACDuring operation, the hybrid energy storage unit is subjected to alternating-current side valley filling and serves as a working condition 11;
b10) when 0 < PL-AC＜PLow-AC,0＜PL-DC＜PLow-DCWhen the hybrid energy storage unit is used, filling the valleys at two sides according to a proportion, and taking the filled valleys as a working condition 12;
c: when P is presentL-AC< 0 and PL-DCWhen the voltage is higher than 0, the system is in an energy transmission mode;
c1) when P is presentL-AC＜0,PL-DC-|PL-AC|＜PH-DCIn the process, the regenerative braking energy generated at the alternating current side is transferred to the direct current side to be fully utilized as a working condition 13;
c2) when P is presentL-AC＜0,0＜|PL-AC|-PL-DC＜PEFS-maxWhen the energy is used, all the energy on the direct current side is derived from the regenerative braking energy on the alternating current side, and the extra regenerative braking energy is absorbed by the energy feedback system to serve as a working condition 14;
c3) when P is presentL-AC＜0,PEFS-max＜|PL-AC|-PL-DC＜PHESS-max+PEFS-maxWhen the energy is used, all the energy on the direct current side is derived from the regenerative braking energy on the alternating current side, the energy feedback system absorbs the regenerative braking energy with the maximum power, and the extra regenerative braking energy is absorbed by the hybrid energy storage device to serve as the working condition 15;
c4) when P is presentL-AC＜0,PHESS-max+PEFS-max＜|PL-AC|-PL-DCWhen the DC side is full of energy, the AC side is full of energyThe energy feedback system and the hybrid energy storage device absorb the regenerative braking energy with the maximum power, and the extra regenerative braking energy returns to the power grid as a working condition 16;
c5) when P is presentL-AC＜0,PH-DC＜PL-DC-|PL-ACWhen the voltage is lower than the preset voltage, the hybrid energy storage unit is used for peak clipping at the direct current side, and the regenerative braking energy generated at the alternating current side is also transmitted to the direct current side for peak clipping as a working condition 17;
when P is presentL-AC> 0 and PL-DCWhen the frequency is less than 0, the system is in an energy transmission mode;
c6) when P is presentL-DC＜0,0＜PL-AC-|PL-DC|＜PH-ACIn the process, the regenerative braking energy generated by the direct current side is transferred to the alternating current side to be fully utilized as the working condition 18;
c7) when P is presentL-DC＜0,0＜|PL-DC|-PL-AC＜PEFS-maxWhen the energy is used, all the energy on the alternating current side comes from the regenerative braking energy on the direct current side, and the extra regenerative braking energy is absorbed by the energy feedback system to serve as a working condition 19;
c8) when P is presentL-DC＜0,PEFS-max＜|PL-DC|-PL-AC＜PHESS-max+PEFS-maxWhen the energy is used, all the energy on the alternating current side comes from the regenerative braking energy on the direct current side, the energy feedback system absorbs the regenerative braking energy with the maximum power, and the extra regenerative braking energy is absorbed by the hybrid energy storage device to serve as the working condition 20;
c9) when P is presentL-DC＜0,PHESS-max+PEFS-max＜|PL-DC|-PL-ACWhen the energy is used, all the energy on the alternating current side is derived from the regenerative braking energy on the direct current side, the energy feedback system and the hybrid energy storage device absorb the regenerative braking energy with the maximum power, and the extra regenerative braking energy is dissipated in a heat energy form to be used as a working condition 21;
c10) when P is presentL-DC＜0,PH-AC＜PL-AC-|PL-DCWhen the voltage is lower than the preset voltage, the hybrid energy storage unit is used for alternating current side peak clipping, and the regenerative braking energy generated by the direct current side is also transmitted to the alternating current side for peak clipping to serve as a working condition 22.
As the above-mentioned embodimentIn step S30, based on the system condition at this time, the power P transmitted by the ac side contact network and the intermediate dc link is optimizedMidDC-DCThe power P of the intermediate DC link transmission and the DC side contact networkMidDC-DCPower P of intermediate DC link transmission and energy feedback systemMidDC-FAnd the power P of the intermediate direct current link transmission and hybrid energy storage unitHESS；
Will PHESSThe low-frequency component is transmitted as an intermediate direct current link and the power P of the storage battery through a low-pass filterMidDC-Bat，PHESS-PMidDC-BatPower P as intermediate DC link transmission and super capacitorMidDC-SC。
In condition 1:
Figure BDA0003100361090000141
in condition 2:
Figure BDA0003100361090000142
in condition 3:
Figure BDA0003100361090000143
in condition 4:
Figure BDA0003100361090000144
in condition 5:
Figure BDA0003100361090000145
in condition 6:
Figure BDA0003100361090000146
in condition 7:
Figure BDA0003100361090000147
in condition 8:
Figure BDA0003100361090000151
in operating condition 9:
Figure BDA0003100361090000152
in condition 10:
Figure BDA0003100361090000153
in operating condition 11:
Figure BDA0003100361090000154
in operating condition 12:
Figure BDA0003100361090000155
in operating condition 13:
Figure BDA0003100361090000156
in condition 14:
Figure BDA0003100361090000157
in operating condition 15:
Figure BDA0003100361090000161
in condition 16:
Figure BDA0003100361090000162
in operating condition 17:
Figure BDA0003100361090000163
in condition 18:
Figure BDA0003100361090000164
in condition 19:
Figure BDA0003100361090000165
in operating condition 20:
Figure BDA0003100361090000166
in operating condition 21:
Figure BDA0003100361090000167
in operating condition 22:
Figure BDA0003100361090000168
as an optimization solution of the above embodiment, in step S40, the reference current of the AC-side contact grid converter is IACrefThe reference current of the direct current side contact network converter is the reference current of the first DC-DC converter and is iDCrefThe reference current of the intermediate direct-current link converter comprises the reference current of the second DC-DC converter and is iBATrefAnd the reference current of the third DC-DC converter is iSCrefThe reference current of the energy-fed system side converter is the reference current of the three-phase AC-DC converter and is iFref；
Reference current I of single-phase AC-DC converterACrefReference current i of the first DC-DC converterDCrefReference current i of the second DC-DC converterBATrefReference current i of the third DC-DC converterSCrefReference current i of three-phase AC-DC converterFrefThe calculation formula is as follows:
Figure BDA0003100361090000171
wherein, VACIs an effective value of the AC side voltage, k1For ac side transformer transformation ratio, VDCIs an effective value of the DC side voltage, VBATIs the battery voltage, VSCIs a super capacitor voltage, VEFSTo be able to feed the system voltage, k2Transformer for energy feed systemAnd (4) transformation ratio.
As an optimization of the above embodiment, as shown in fig. 3, in step S50, when each converter is controlled based on each reference signal obtained in step S40: and (3) single-phase AC-DC converter voltage outer ring prediction current inner ring double-ring control: the voltage reference value u of the intermediate direct current link is compareddc-refAnd the actual value udcSubtracting the input signal from the input signal to form a PI controller, forming a voltage outer loop control, and adding IACrefAnd obtaining a switching signal for controlling the single-phase AC-DC converter through predictive current control and PWM modulation.
In step S50, as shown in fig. 4, the first DC-DC converter, the second DC-DC converter, and the third DC-DC converter adopt PI control when controlling the converters based on the reference signals obtained in step S40: from a reference current iDCref、iBATref、iSCrefRespectively with the actual value i of the direct current side currentDCActual value i of current of storage battery in hybrid energy storage unitBATActual value i of super capacitor current in hybrid energy storage unitSCAnd obtaining switching signals for controlling the first DC-DC converter, the second DC-DC converter and the third DC-DC converter through PI control and a hysteresis comparator.
In step S50, as shown in fig. 5, when each inverter is controlled based on each reference signal obtained in step S40: the three-phase AC-DC converter adopts dq decoupling control: from a reference current iFrefAnd the actual values of the three-phase voltage and the three-phase current of the energy feedback system are subjected to park transformation and park inverse transformation to complete decoupling control, and then a switching signal for controlling the three-phase AC-DC converter is obtained through PWM modulation.
In order to match the implementation of the method of the invention, based on the same inventive concept, as shown in fig. 6, the invention further provides a flexible power supply device for rail transit, which comprises a step-down transformer 1, a single-phase AC-DC converter 2, a direct-current voltage-stabilizing capacitor 3, a first DC-DC converter 4, a second DC-DC converter 5, a third DC-DC converter 6, a super capacitor 7, a storage battery 8, a three-phase AC-DC converter 9 and an LCL filter circuit 10; the input end of the step-down transformer 1 is connected with an alternating current side contact network, and the output end of the step-down transformer 1 is connected with the single-phase AC-DC converter 2; the output end of the single-phase AC-DC converter 2 is connected with a direct-current voltage-stabilizing capacitor 3, a first DC-DC converter 4, a second DC-DC converter 5, a third DC-DC converter 6 and a three-phase AC-DC converter 9 in parallel; the other end of the first DC-DC converter 4 is connected with a direct current side contact network; the output end of the second DC-DC converter 5 is connected with a super capacitor 7, and the output end of the third DC-DC converter 6 is connected with a storage battery 8 to form a hybrid energy storage unit; and the output end of the three-phase AC-DC converter 9 is connected with the LCL filter circuit 10 and then is connected to an energy feed system.
Wherein, the single-phase AC-DC converter 2 can adopt a two-level H-bridge topology, a cascade H-bridge topology or an MMC topology and the like; the first DC-DC converter 4, the second DC-DC converter 5 and the third DC-DC converter 6 adopt bidirectional Buck-Boost converters, and filter inductors are connected to the output side; the three-phase AC-DC converter 9 adopts a two-level three-leg H-bridge topology.
Fig. 7 is a schematic diagram of a dual-current system traction power supply system and an electric phase separation (dead zone) thereof, and the system mainly comprises a traction substation, a contact network, an electric locomotive, a steel rail and an electric phase separation (dead zone). The rail transit flexible power supply device as shown in fig. 6 is installed at an electric phase splitting (dead zone) position of a double-current system traction power supply system, a step-down transformer of the rail transit flexible power supply device can be connected with an AC 25kV system alternating current contact network, and an output port of a direct current converter can be connected with a DC 1500V system direct current contact network.
Of the 22 operating conditions, a typical operating condition was selected for simulation in each mode, i.e., operating condition 3 (regenerative braking mode), operating condition 4 (traction mode), and operating condition 15 (energy transmission mode), and the associated waveforms are shown in fig. 8:
and (3) working condition within 0-1 s, setting the AC side to generate 4MW regenerative braking power, setting the DC side to generate 2.39MW regenerative braking power, giving priority to the energy feedback system for the part of power, and transmitting the rest of power to the hybrid energy storage device. The voltage of the intermediate direct current link is stabilized at 10kV, the power factor of the single-phase AC-DC converter is close to 1, the power absorbed by the hybrid energy storage device is 4MW, and the current waveform of each converter is stable;
working condition 4 is set in 1 st to 2s, the alternating current side needs 2.5MW peak clipping power, the direct current side needs 1.5MW peak clipping power, and the hybrid energy storage device generates peak clipping power of the alternating current side and the direct current side. The voltage of the intermediate direct current link is stabilized at 10kV, the power factor of the single-phase AC-DC converter is close to-1, the power released by the hybrid energy storage device is 4MW, the current waveform of each converter is stable, and the response speed is high;
and (3) setting a working condition 15 in 2-3 s, setting the regenerative braking power of 6MW generated by the alternating current side, setting the traction power of the direct current side to be 1MW, preferentially transmitting the regenerative braking energy generated by the alternating current side to the direct current side for utilization, firstly injecting the rest regenerative braking energy into the energy feedback system, setting the maximum absorbable power of the energy feedback system to be 2.39MW, and then injecting the rest regenerative braking energy into the hybrid energy storage device, wherein the absorbed power is 2.61 MW. The voltage of the intermediate direct current link is stabilized at 10kV, the power factor of the single-phase AC-DC converter is close to 1, the power absorbed by the hybrid energy storage device is 2.61MW, the current waveform of each converter is stable, and the response speed is high.
The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (10)

1. A rail transit flexible power supply coordination control method is characterized by comprising the following steps:
s10, respectively collecting voltage and current of a load at outlets of the power substations on the two sides of the alternating current and the direct current, and calculating to obtain instantaneous power of the load;
s20, according to the load instantaneous power, based on the system working mode division, judging the working mode of the system at the moment, and obtaining the system working condition under the corresponding mode;
s30, based on the system working condition, obtaining the power transmitted from the AC side contact network to the intermediate DC link, the power transmitted from the intermediate DC link to the DC side contact network, the power transmitted from the intermediate DC link to the energy feedback system, and the power transmitted from the intermediate DC link to the hybrid energy storage unit;
s40, calculating a reference current of each converter from the voltage value of the connected device of each converter based on each power acquired in step S30; obtaining a reference current of an alternating current side contact network converter, a reference current of a direct current side contact network converter, a reference current of a hybrid energy storage unit converter and a reference current of an energy feed system converter;
s50, the inverters are controlled based on the reference signals obtained in step S40.
2. The rail transit flexible power supply coordination control method according to claim 1, characterized in that according to the load instantaneous power PL-ACAnd PL-DCJudging the working mode of the system at the moment based on the system working mode division; according to the instantaneous power P of the loadL-ACAnd PL-DCBased on a valley fill threshold value P preset for the AC side transformationLow-ACPeak clipping threshold value PH-ACA valley fill threshold value P preset for DC side transformationLow-DCPeak clipping threshold value PH-DCMaximum charge and discharge power P of hybrid energy storage unitHESS-maxAnd the maximum power P absorbable by the energy feedback systemEFS-maxJudging the system working condition at the moment; the method comprises the following steps:
a: when P is presentL-AC< 0 and PL-DCWhen the voltage is less than 0, the system is in a regenerative braking mode, and the regenerative braking energy of the contact network at the alternating current side is transmitted to the intermediate direct current link through the single-phase AC-DC converter; the regenerative braking energy of the direct-current side contact network is transmitted to the intermediate direct-current link through the first DC-DC converter;
a1)|PL-AC+PL-DC|＜PEFS-maxthe energy feedback system absorbs the regenerative braking energy transmitted to the middle direct current link by the lines on two sides through the three-phase AC-DC converter as a working condition 1;
a2)PEFS-max＜|PL-AC+PL-DC|＜PHESS-max+PEFS-maxregenerative braking energy of the two-sided line cannot be completedWhen the energy is absorbed by the energy feedback system, the hybrid energy storage unit participates in absorbing the part of regenerative braking energy as a working condition 2;
a3)PHESS-max+PEFS-max＜|PL-AC+PL-DCif the hybrid energy storage unit reaches the maximum charging power and the unabsorbed regenerative braking energy exists at the moment, the energy on the alternating current side is transmitted to a power grid connected with a traction substation in a reverse mode, and the part of energy on the direct current side is dissipated in a heat energy mode to serve as a working condition 3;
b: when P is presentL-AC> 0 and PL-DCWhen the speed is higher than 0, the system is in a traction mode;
b1) when P is presentH-AC＜PL-AC，PH-DC＜PL-DCDuring the operation, the energy storage components of the hybrid energy storage unit are subjected to peak clipping at two sides according to a proportion respectively, and the operation condition is set as a working condition 4;
b2) when P is presentH-AC＜PL-AC,PL-AC-PHESS-max＜PH-AC,PLow-DC＜PL-DC＜PH-DCDuring operation, the hybrid energy storage unit performs peak clipping on the alternating current side, and the working condition is set as 5;
b3) when P is presentH-AC＜PL-AC,PH-AC＜PL-AC-PHESS-max,PLow-DC＜PL-DC＜PH-DCWhen the working condition is 6, the peak clipping capacity of the hybrid energy storage unit is insufficient, and the direct current side is the alternating current side for clipping the peak;
b4) when P is presentLow-AC＜PL-AC＜PH-AC,PH-DC＜PL-DC,PL-DC-PHESS-max＜PH-DCDuring operation, the hybrid energy storage unit performs peak clipping on the direct current side as a working condition 7;
b5) when P is presentLow-AC＜PL-AC＜PH-AC,PH-DC＜PL-DC,PH-DC＜PL-DC-PHESS-maxWhen the working condition is 8, the peak clipping capacity of the hybrid energy storage unit is insufficient, and the alternating current side is the alternating current side for clipping the peak;
b6) when P is presentLow-AC＜PL-AC＜PH-AC,PLow-DC＜PL-DC＜PH-DCThe hybrid energy storage unit is not put into operation, andenergy is not exchanged on the two sides, and the working condition is 9;
b7) when P is presentLow-AC＜PL-AC＜PH-AC,0＜PL-DC＜PLow-DCIn the process, the hybrid energy storage unit is subjected to direct-current side valley filling and serves as a working condition 10;
b9) when P is presentLow-DC＜PL-DC＜PH-DC,0＜PL-AC＜PLow-ACDuring operation, the hybrid energy storage unit is subjected to alternating-current side valley filling and serves as a working condition 11;
b10) when 0 < PL-AC＜PLow-AC,0＜PL-DC＜PLow-DCWhen the hybrid energy storage unit is used, filling the valleys at two sides according to a proportion, and taking the filled valleys as a working condition 12;
c: when P is presentL-AC< 0 and PL-DCWhen the voltage is higher than 0, the system is in an energy transmission mode;
c1) when P is presentL-AC＜0,PL-DC-|PL-AC|＜PH-DCIn the process, the regenerative braking energy generated at the alternating current side is transferred to the direct current side to be fully utilized as a working condition 13;
c2) when P is presentL-AC＜0,0＜|PL-AC|-PL-DC＜PEFS-maxWhen the energy is used, all the energy on the direct current side is derived from the regenerative braking energy on the alternating current side, and the extra regenerative braking energy is absorbed by the energy feedback system to serve as a working condition 14;
c3) when P is presentL-AC＜0,PEFS-max＜|PL-AC|-PL-DC＜PHESS-max+PEFS-maxWhen the energy is used, all the energy on the direct current side is derived from the regenerative braking energy on the alternating current side, the energy feedback system absorbs the regenerative braking energy with the maximum power, and the extra regenerative braking energy is absorbed by the hybrid energy storage device to serve as the working condition 15;
c4) when P is presentL-AC＜0,PHESS-max+PEFS-max＜|PL-AC|-PL-DCWhen the energy is used, all the energy on the direct current side is derived from the regenerative braking energy on the alternating current side, the energy feedback system and the hybrid energy storage device absorb the regenerative braking energy with the maximum power, and the extra regenerative braking energy returns to the power grid as a working condition 16;
c5) when P is presentL-AC＜0,PH-DC＜PL-DC-|PL-ACWhen the voltage is lower than the preset voltage, the hybrid energy storage unit is used for peak clipping at the direct current side, and the regenerative braking energy generated at the alternating current side is also transmitted to the direct current side for peak clipping as a working condition 17;
when P is presentL-AC> 0 and PL-DCWhen the frequency is less than 0, the system is in an energy transmission mode;
c6) when P is presentL-DC＜0,0＜PL-AC-|PL-DC|＜PH-ACIn the process, the regenerative braking energy generated by the direct current side is transferred to the alternating current side to be fully utilized as the working condition 18;
c7) when P is presentL-DC＜0,0＜|PL-DC|-PL-AC＜PEFS-maxWhen the energy is used, all the energy on the alternating current side comes from the regenerative braking energy on the direct current side, and the extra regenerative braking energy is absorbed by the energy feedback system to serve as a working condition 19;
c8) when P is presentL-DC＜0,PEFS-max＜|PL-DC|-PL-AC＜PHESS-max+PEFS-maxWhen the energy is used, all the energy on the alternating current side comes from the regenerative braking energy on the direct current side, the energy feedback system absorbs the regenerative braking energy with the maximum power, and the extra regenerative braking energy is absorbed by the hybrid energy storage device to serve as the working condition 20;
c9) when P is presentL-DC＜0,PHESS-max+PEFS-max＜|PL-DC|-PL-ACWhen the energy is used, all the energy on the alternating current side is derived from the regenerative braking energy on the direct current side, the energy feedback system and the hybrid energy storage device absorb the regenerative braking energy with the maximum power, and the extra regenerative braking energy is dissipated in a heat energy form to be used as a working condition 21;
c10) when P is presentL-DC＜0,PH-AC＜PL-AC-|PL-DCWhen the voltage is lower than the preset voltage, the hybrid energy storage unit is used for alternating current side peak clipping, and the regenerative braking energy generated by the direct current side is also transmitted to the alternating current side for peak clipping to serve as a working condition 22.
3. The rail transit flexible power supply coordination control method according to claim 2, characterized in that in step S30, based on the system condition at that time, the power P transmitted by the ac side contact network and the intermediate dc linkMidDC-DCIntermediate direct current linkTransmitting power P to a direct current side contact networkMidDC-DCPower P of intermediate DC link transmission and energy feedback systemMidDC-FAnd the power P of the intermediate direct current link transmission and hybrid energy storage unitHESS；
Will PHESSThe low-frequency component is transmitted as an intermediate direct current link and the power P of the storage battery through a low-pass filterMidDC-Bat，PHESS-PMidDC-BatPower P as intermediate DC link transmission and super capacitorMidDC-SC。
4. The rail transit flexible power supply coordination control method according to claim 3, wherein in step S30, each power value is calculated based on the system operating condition at that time, and the method comprises:
in condition 1:
Figure FDA0003100361080000041
in condition 2:
Figure FDA0003100361080000042
in condition 3:
Figure FDA0003100361080000043
in condition 4:
Figure FDA0003100361080000044
in condition 5:
Figure FDA0003100361080000045
in condition 6:
Figure FDA0003100361080000046
in condition 7:
Figure FDA0003100361080000047
in condition 8:
Figure FDA0003100361080000051
in operating condition 9:
Figure FDA0003100361080000052
in condition 10:
Figure FDA0003100361080000053
in operating condition 11:
Figure FDA0003100361080000054
in operating condition 12:
Figure FDA0003100361080000055
in operating condition 13:
Figure FDA0003100361080000056
in condition 14:
Figure FDA0003100361080000057
in operating condition 15:
Figure FDA0003100361080000061
in condition 16:
Figure FDA0003100361080000062
in operating condition 17:
Figure FDA0003100361080000063
in condition 18:
Figure FDA0003100361080000064
in condition 19:
Figure FDA0003100361080000065
in operating condition 20:
Figure FDA0003100361080000066
in operating condition 21:
Figure FDA0003100361080000067
in operating condition 22:
Figure FDA0003100361080000068
5. the rail transit flexible power supply coordination control method according to claim 4, characterized in that, in step S40, the reference current of the AC-side contact network converter is the reference current of the single-phase AC-DC converter is IACrefThe reference current of the direct current side contact network converter is the reference current of the first DC-DC converter and is iDCrefThe reference current of the intermediate direct-current link converter comprises the reference current of the second DC-DC converter and is iBATrefAnd the reference current of the third DC-DC converter is iSCrefThe reference current of the energy-fed system side converter is the reference current of the three-phase AC-DC converter and is iFref；
Reference current I of single-phase AC-DC converterACrefReference current i of the first DC-DC converterDCrefReference current i of the second DC-DC converterBATrefReference current i of the third DC-DC converterSCrefReference current i of three-phase AC-DC converterFrefThe calculation formula is as follows:
Figure FDA0003100361080000071
wherein, VACIs an effective value of the AC side voltage, k1For ac side transformer transformation ratio, VDCIs an effective value of the DC side voltage, VBATIs the battery voltage, VSCIs a super capacitor voltage, VEFSTo be able to feed the system voltage, k2The transformation ratio of the system transformer is fed.
6. The rail transit flexible power supply coordination control method according to any one of claims 2-5, characterized in that in step S50, when controlling each converter based on each reference signal obtained in step S40: and (3) single-phase AC-DC converter voltage outer ring prediction current inner ring double-ring control: the voltage reference value u of the intermediate direct current link is compareddc-refAnd the actual value udcSubtracting the input signal from the input signal to form a PI controller, forming a voltage outer loop control, and adding IACrefAnd obtaining a switching signal for controlling the single-phase AC-DC converter through predictive current control and PWM modulation.
7. The rail transit flexible power supply coordination control method according to any one of claims 2 to 5, characterized in that in step S50, when controlling each converter based on each reference signal obtained in step S40, PI control is adopted for the first DC-DC converter, the second DC-DC converter and the third DC-DC converter: from a reference current iDCref、iBATref、iSCrefRespectively with the actual value i of the direct current side currentDCActual value i of current of storage battery in hybrid energy storage unitBATActual value i of super capacitor current in hybrid energy storage unitSCAnd obtaining switching signals for controlling the first DC-DC converter, the second DC-DC converter and the third DC-DC converter through PI control and a hysteresis comparator.
8. The rail transit flexible power supply coordination control method according to any one of claims 2-5, characterized in that in step S50, on a step-by-step basisWhen each of the reference signals obtained in step S40 controls each of the inverters: the three-phase AC-DC converter adopts dq decoupling control: from a reference current iFrefAnd the actual values of the three-phase voltage and the three-phase current of the energy feedback system are subjected to park transformation and park inverse transformation to complete decoupling control, and then a switching signal for controlling the three-phase AC-DC converter is obtained through PWM modulation.
9. The rail transit flexible power supply device is characterized by comprising a step-down transformer (1), a single-phase AC-DC converter (2), a direct-current voltage-stabilizing capacitor (3), a first DC-DC converter (4), a second DC-DC converter (5), a third DC-DC converter (6), a super capacitor (7), a storage battery (8), a three-phase AC-DC converter (9) and an LCL filter circuit (10); the input end of the step-down transformer (1) is connected with an alternating-current side contact network, and the output end of the step-down transformer (1) is connected with the single-phase AC-DC converter (2); the output end of the single-phase AC-DC converter (2) is connected with a direct-current voltage-stabilizing capacitor (3), a first DC-DC converter (4), a second DC-DC converter (5), a third DC-DC converter (6) and a three-phase AC-DC converter (9) in parallel; the other end of the first DC-DC converter (4) is connected with a direct current side contact network; the output end of the second DC-DC converter (5) is connected with a super capacitor (7), and the output end of the third DC-DC converter (6) is connected with a storage battery (8) to form a hybrid energy storage unit; and the output end of the three-phase AC-DC converter (9) is connected with the LCL filter circuit (10) and then is connected to the energy feed system.
10. The rail transit flexible power supply device according to claim 9, characterized in that the single-phase AC-DC converter (2) adopts a two-level H-bridge topology, a cascaded H-bridge topology or an MMC topology; the first DC-DC converter (4), the second DC-DC converter (5) and the third DC-DC converter (6) adopt bidirectional Buck-Boost converters, and filter inductors are connected to the output side; the three-phase AC-DC converter (9) adopts a two-level three-bridge-arm H-bridge topology.
CN202110622325.3A 2021-06-04 2021-06-04 Flexible power supply device for rail transit and coordination control method Active CN113381429B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110622325.3A CN113381429B (en) 2021-06-04 2021-06-04 Flexible power supply device for rail transit and coordination control method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110622325.3A CN113381429B (en) 2021-06-04 2021-06-04 Flexible power supply device for rail transit and coordination control method

Publications (2)

Publication Number Publication Date
CN113381429A true CN113381429A (en) 2021-09-10
CN113381429B CN113381429B (en) 2022-05-20

Family

ID=77575735

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110622325.3A Active CN113381429B (en) 2021-06-04 2021-06-04 Flexible power supply device for rail transit and coordination control method

Country Status (1)

Country Link
CN (1) CN113381429B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114498706A (en) * 2022-01-28 2022-05-13 西南交通大学 Urban rail hybrid regenerative energy utilization system control method based on power distribution

Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104648170A (en) * 2015-01-27 2015-05-27 株洲南车时代电气股份有限公司 Electric traction system of double current system inter-city vehicle
CN105459839A (en) * 2015-11-24 2016-04-06 唐山轨道客车有限责任公司 Dual-mode current collecting system and method
CN107769239A (en) * 2017-09-11 2018-03-06 北京交通大学 A kind of new alternating electromotive force electronic transformer topological structure
WO2018180889A1 (en) * 2017-03-31 2018-10-04 パナソニックＩｐマネジメント株式会社 Power conversion device, power conversion system, and dc power supply device
US20190067939A1 (en) * 2016-05-18 2019-02-28 China Electric Power Research Institute Company Limited Multi-time-scale digital/analog hybrid simulation system and method for power distribution network and storage medium
CN208923831U (en) * 2018-11-13 2019-05-31 中国铁道科学研究院集团有限公司 A kind of alternating current-direct current mixed support power supply system
CN110535192A (en) * 2019-09-12 2019-12-03 陕西科技大学 A kind of alternating current-direct current mixing micro-capacitance sensor system and its control method based on parallel-connection network side converter
CN110535153A (en) * 2019-04-23 2019-12-03 内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司 Mixed energy storage system DC/AC converter control method for coordinating and device
WO2020020325A1 (en) * 2018-07-27 2020-01-30 比亚迪股份有限公司 Rail transport power supply system
CN110789360A (en) * 2019-10-31 2020-02-14 湖南大学 Multi-system traction transmission system and method based on modular multilevel converter
CN110829435A (en) * 2019-10-09 2020-02-21 西南交通大学 Electrified railway energy storage type traction power supply system and control method thereof
CN111541258A (en) * 2020-03-03 2020-08-14 北方工业大学 Large signal stability control method of alternating current-direct current hybrid micro-grid system in island mode
CN211606377U (en) * 2020-03-10 2020-09-29 株洲中车时代电气股份有限公司 Train and traction system of train of double-flow system thereof
CN112467739A (en) * 2020-12-15 2021-03-09 通号（长沙）轨道交通控制技术有限公司 Urban rail power supply system configuration method of hybrid regenerative braking energy utilization device
US20210098994A1 (en) * 2019-09-30 2021-04-01 James Arnim White Renewable Energy Metering System
CN112803582A (en) * 2021-03-23 2021-05-14 西南交通大学 Alternating current-direct current hybrid subway power supply system and coordination control method thereof

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104648170A (en) * 2015-01-27 2015-05-27 株洲南车时代电气股份有限公司 Electric traction system of double current system inter-city vehicle
CN105459839A (en) * 2015-11-24 2016-04-06 唐山轨道客车有限责任公司 Dual-mode current collecting system and method
US20190067939A1 (en) * 2016-05-18 2019-02-28 China Electric Power Research Institute Company Limited Multi-time-scale digital/analog hybrid simulation system and method for power distribution network and storage medium
WO2018180889A1 (en) * 2017-03-31 2018-10-04 パナソニックＩｐマネジメント株式会社 Power conversion device, power conversion system, and dc power supply device
CN107769239A (en) * 2017-09-11 2018-03-06 北京交通大学 A kind of new alternating electromotive force electronic transformer topological structure
WO2020020325A1 (en) * 2018-07-27 2020-01-30 比亚迪股份有限公司 Rail transport power supply system
CN208923831U (en) * 2018-11-13 2019-05-31 中国铁道科学研究院集团有限公司 A kind of alternating current-direct current mixed support power supply system
CN110535153A (en) * 2019-04-23 2019-12-03 内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司 Mixed energy storage system DC/AC converter control method for coordinating and device
CN110535192A (en) * 2019-09-12 2019-12-03 陕西科技大学 A kind of alternating current-direct current mixing micro-capacitance sensor system and its control method based on parallel-connection network side converter
US20210098994A1 (en) * 2019-09-30 2021-04-01 James Arnim White Renewable Energy Metering System
CN110829435A (en) * 2019-10-09 2020-02-21 西南交通大学 Electrified railway energy storage type traction power supply system and control method thereof
CN110789360A (en) * 2019-10-31 2020-02-14 湖南大学 Multi-system traction transmission system and method based on modular multilevel converter
CN111541258A (en) * 2020-03-03 2020-08-14 北方工业大学 Large signal stability control method of alternating current-direct current hybrid micro-grid system in island mode
CN211606377U (en) * 2020-03-10 2020-09-29 株洲中车时代电气股份有限公司 Train and traction system of train of double-flow system thereof
CN112467739A (en) * 2020-12-15 2021-03-09 通号（长沙）轨道交通控制技术有限公司 Urban rail power supply system configuration method of hybrid regenerative braking energy utilization device
CN112803582A (en) * 2021-03-23 2021-05-14 西南交通大学 Alternating current-direct current hybrid subway power supply system and coordination control method thereof

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
CHAOXIAN WU ET AL: "Optimal Sizing of Onboard Energy Storage Devices for Electrified Railway Systems", 《IEEE TRANSACTIONS ON TRANSPORTATION ELECTRIFICATION》 *
周志余: "基于超级电容的双流制机车储能系统研究", 《中国优秀硕士学位论文全文数据库 工程科技Ⅱ辑》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114498706A (en) * 2022-01-28 2022-05-13 西南交通大学 Urban rail hybrid regenerative energy utilization system control method based on power distribution
CN114498706B (en) * 2022-01-28 2023-03-24 西南交通大学 Urban rail hybrid regenerative energy utilization system control method based on power distribution

Also Published As

Publication number Publication date
CN113381429B (en) 2022-05-20

Similar Documents

Publication Publication Date Title
CN110829435B (en) Electrified railway energy storage type traction power supply system and control method thereof
CN110654241B (en) Optimized energy interconnection system for urban rail train
CN109572491B (en) Electrified railway traction network power supply structure and control method thereof
CN103311950B (en) City railway train regenerating braking energy absorbs system and method
CN107776416A (en) A kind of track traffic hybrid power circuit, stored energy power bag and its method of supplying power to
WO2015014249A1 (en) New energy-based hybrid bidirectional interactive dc traction power supply system
CN113263920B (en) Vehicle-mounted hybrid energy storage system of electrified railway and energy management method thereof
CN110718930A (en) Railway traction network regenerative braking energy utilization device
Kaleybar et al. EV charging station integrated with electric railway system powering by train regenerative braking energy
CN110649623A (en) Energy utilization system for railway traction network
CN104527960A (en) Ship braking energy control system and method
CN113381429B (en) Flexible power supply device for rail transit and coordination control method
CN105790317B (en) A kind of rail traffic vehicles main circuit suitable for multiple power sources power supply
CN110071648A (en) The progress control method of PWM rectifier in a kind of city rail traffic tractive power supply system
Kaleybar et al. Sustainable Electrified Transportation Systems: Integration of EV and E-bus Charging Infrastructures to Electric Railway Systems
CN112803504A (en) Multifunctional integrated converter equipment and control method thereof
Zhou et al. Research on comprehensive utilization technology of regenerative braking energy for heavy haul railway
CN209505511U (en) A kind of electric railway traction net powered construction
Lai et al. Power Flow Optimization and Control Strategy for Energy Router in Dual Mode Traction Power Supply System
CN114726010A (en) Regenerative braking energy storage device of double-current traction power supply line and control method thereof
CN217215985U (en) Multi-station comprehensive renewable energy utilization device for heavy haul railway
Dai et al. Analysis and Simulation of Energy Router Suitable for Metro Power Supply Network
Lukianov et al. Power converter interface for urban DC traction substations-solutions and functionality.
CN115800350B (en) Rail transit vehicle and regenerative braking energy comprehensive utilization device and method thereof
CN204578108U (en) A kind of converter device and 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