CN114792971A - Grouping centralized direct current energy consumption device for optimizing direct current voltage control and control method - Google Patents

Grouping centralized direct current energy consumption device for optimizing direct current voltage control and control method Download PDF

Info

Publication number
CN114792971A
CN114792971A CN202210712131.7A CN202210712131A CN114792971A CN 114792971 A CN114792971 A CN 114792971A CN 202210712131 A CN202210712131 A CN 202210712131A CN 114792971 A CN114792971 A CN 114792971A
Authority
CN
China
Prior art keywords
energy consumption
centralized
direct current
modules
energy
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
CN202210712131.7A
Other languages
Chinese (zh)
Other versions
CN114792971B (en
Inventor
郭铭群
赵峥
田园园
李明
张涛
薛英林
李探
黄曹炜
罗舒翰
滕尚甫
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.)
State Grid Jiangxi Electric Power Co ltd
State Grid Economic And Technological Research Institute Co LtdB412 State Grid Office
Original Assignee
State Grid Jiangxi Electric Power Co ltd
State Grid Economic And Technological Research Institute Co LtdB412 State Grid Office
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 State Grid Jiangxi Electric Power Co ltd, State Grid Economic And Technological Research Institute Co LtdB412 State Grid Office filed Critical State Grid Jiangxi Electric Power Co ltd
Priority to CN202210712131.7A priority Critical patent/CN114792971B/en
Publication of CN114792971A publication Critical patent/CN114792971A/en
Application granted granted Critical
Publication of CN114792971B publication Critical patent/CN114792971B/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
    • H02J1/00—Circuit arrangements for dc mains or dc distribution networks
    • H02J1/14—Balancing the load in a network
    • 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
    • H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/08—Modifications for protecting switching circuit against overcurrent or overvoltage
    • H03K17/081—Modifications for protecting switching circuit against overcurrent or overvoltage without feedback from the output circuit to the control circuit
    • H03K17/08116—Modifications for protecting switching circuit against overcurrent or overvoltage without feedback from the output circuit to the control circuit in composite switches
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
    • H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
    • H03K17/567—Circuits characterised by the use of more than one type of semiconductor device, e.g. BIMOS, composite devices such as IGBT
    • 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
    • H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
    • H02J2003/365—Reducing harmonics or oscillations in HVDC

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Electrical Variables (AREA)
  • Supply And Distribution Of Alternating Current (AREA)
  • Air Conditioning Control Device (AREA)
  • Selective Calling Equipment (AREA)

Abstract

The invention belongs to the field of direct current transmission, and relates to a grouping centralized direct current energy consumption device, a control method and a readable medium for optimizing direct current voltage control. The problem of large direct-current voltage switching spike of the centralized direct-current energy consumption device is effectively solved through the external parallel capacitor branch, and the steady-state fluctuation amplitude of direct-current voltage during the action period of the centralized direct-current energy consumption device is effectively reduced through the grouping arrangement structure and the grouping control strategy, so that the direct-current voltage control effect of the centralized direct-current energy consumption device is obviously optimized.

Description

Grouping centralized direct current energy consumption device for optimizing direct current voltage control and control method
Technical Field
The invention relates to a grouping centralized direct current energy consumption device, a control method and a readable medium for optimizing direct current voltage control, belongs to the field of direct current power transmission, and particularly relates to a design of a system for transmitting open-sea wind power out through flexible direct current.
Background
The flexible direct current transmission is an optimal technical scheme for large-capacity and long-distance open sea wind power grid connection. In order to solve the problem of surplus power after the fault of an alternating current power grid at the receiving end of a remote sea wind power flexible direct current system, a direct current energy consumption device with flexibly controllable consumed power must be introduced to realize fault ride-through, wherein a centralized direct current energy consumption device is formed by connecting cascade sub-modules in series with resistors which are arranged in a centralized manner, and the device is favored due to the advantages of compact structure, simplicity in control, no need of configuring a water cooling system, low cost and the like. However, in the switching process of the centralized direct current energy consumption device, the integral switching and integral switching of the energy consumption module is realized through hard switching on/off of all power devices, the power impact is large, the control effect is not ideal enough, a large direct current voltage fluctuation range is often caused, a large switching peak is easily generated on the direct current voltage between electrodes in the instant of switching on/off of the devices, the switching peak frequently appears in the enabling period of the direct current energy consumption device, the direct current voltage control effect is greatly reduced, and related electrical equipment frequently bears the impact, so that the system operation safety is possibly seriously influenced.
Disclosure of Invention
In view of the above problems, an object of the present invention is to provide a grouped centralized dc energy consuming device, a control method, and a readable medium for optimizing dc voltage control, which effectively solve the problem of large dc voltage switching spikes of the centralized dc energy consuming device through an external parallel capacitor branch, and effectively reduce the steady-state fluctuation range of dc voltage during the action of the centralized dc energy consuming device by using a grouped arrangement structure and a grouped control strategy, thereby significantly optimizing the dc voltage control effect of the centralized dc energy consuming device.
In order to achieve the purpose, the invention provides the following technical scheme: a grouping centralized direct current energy consumption device for optimizing direct current voltage control is connected between a direct current positive electrode and a direct current negative electrode and comprises an upper group and a lower group which are symmetrical, wherein the upper group and the lower group respectively comprise a resistor and a plurality of energy consumption modules, the energy consumption modules are connected in series and are connected in series with the resistor, the upper group and the lower group are respectively connected with a capacitor in parallel, and the upper group and the lower group are grounded through the upper group and the lower group of junctions.
Furthermore, the energy consumption module comprises a P-type field effect transistor and a diode which is connected with the P-type field effect transistor in an anti-parallel mode.
Further, at the moment when the energy consumption module is put into operation, the parallel capacitor discharges electricity to the energy consumption module, and a direct-current voltage input peak is restrained; at the moment when the energy consumption module is cut out, surplus power charges the parallel capacitor, and therefore the peak cut-out of the direct-current voltage is restrained.
Further, when two sets of energy-consuming modules are put into operation, the power of the energy-consuming branch isP N The discharge power of the capacitor isP N -△P(ii) a When two sets of energy-consuming modules are cut off, the power of energy-consuming branch circuit is 0, and the discharge power of capacitor is deltaP(ii) a When one set of energy consumption module is put into and the other set of energy consumption module is cut out quickly, the power of the energy consumption branch is 1/2P N If ΔP<1/2P N The capacitor discharge power at this time is 1/2P N -△PIf ΔP>1/2P N Then the capacitor charging power is delta at this timeP-1/2P N If ΔP=1/2P N The capacitor has no charge and discharge power at this time.
Further, the maximum value of the steady-state direct-current voltage fluctuation of the grouped centralized direct-current energy consumption device is as follows:
Figure 509411DEST_PATH_IMAGE001
wherein, U is a steady-state direct-current voltage, C is an equivalent capacitance, and T is a unit carrier period.
The invention also discloses a control method of the grouped centralized direct current energy consumption device for optimizing direct current voltage control, which uses any one of the grouped centralized direct current energy consumption devices and comprises the following steps: generating a duty ratio a of the energy consumption module fast input through proportional integral control based on the direct-current voltage reference value; in the enabling period of the direct current energy consumption device, the phase difference of the carriers of the upper and lower groups of energy consumption modules is 180 degrees; and comparing the duty ratio a with the carriers of the upper and lower groups of energy consumption modules to generate a switching-on or switching-off instruction of the energy consumption modules.
Furthermore, when the duty ratio a is larger than the carrier, the energy consumption modules of all the sub-modules in the corresponding group are conducted, and the energy consumption modules are quickly put into use; and when the duty ratio a is smaller than the carrier wave, the energy consumption modules of all the sub-modules in the corresponding group are turned off, so that the energy consumption modules are quickly exited.
Further, the higher the actual value of the direct-current voltage is, the larger the duty ratio a is.
Further, the carrier wave is a triangular carrier wave, the upper limit value and the lower limit value of the triangular carrier wave are respectively 1 and 0, and the frequency of the triangular carrier wave is determined according to the switching frequency of the energy consumption module.
The invention also discloses a computer readable storage medium, on which a computer program is stored, the computer program is executed by a processor to implement the control method of any one of the above grouped centralized direct current energy consumption devices for optimizing direct current voltage control.
Due to the adoption of the technical scheme, the invention has the following advantages: the invention provides a topological structure and a control method of a grouping centralized direct current energy consumption device for optimizing a direct current voltage control effect, which effectively solve the problem of large direct current voltage switching peak of the centralized direct current energy consumption device through an external parallel capacitor branch, effectively reduce the steady state fluctuation range of direct current voltage during the action of the centralized direct current energy consumption device by adopting a grouping arrangement structure and a grouping control strategy, obviously optimize the direct current voltage control effect of the centralized direct current energy consumption device, and have huge practical value and wide application prospect in the field of sending out far-sea wind power through flexible direct current.
Drawings
Fig. 1 is a schematic structural diagram of a grouped centralized dc energy consumption device for optimizing dc voltage control according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a control method of a grouped centralized DC energy consuming device according to an embodiment of the present invention, where Udc is the actual DC operating voltage; udcref is the dc reference voltage; a is the duty ratio of the fast input of the energy consumption module; f1 is a switching instruction of the upper group of direct current energy consumption devices; f2 is a switching instruction of the lower group of direct current energy consumption devices;
fig. 3 is a schematic diagram of a carrier and a duty cycle in the upper set of centralized dc power consumption devices according to an embodiment of the invention;
fig. 4 is a schematic diagram of a carrier and a duty cycle in the lower set of centralized dc energy consumption devices according to an embodiment of the present invention;
fig. 5 is a schematic diagram of switching commands of upper and lower dc energy consuming devices when the duty ratio a is <1/2 in an embodiment of the present invention;
fig. 6 is a schematic diagram of switching instructions of upper and lower groups of dc energy consumption devices when the duty ratio a =1/2 in an embodiment of the present invention;
fig. 7 is a schematic diagram of switching commands of upper and lower dc energy consuming devices when the duty ratio a is greater than 1/2 in an embodiment of the present invention;
FIG. 8 is a DC voltage waveform during the operation of the DC energy consuming device under the condition of receiving end AC system failure when the system surplus power is 1100MW according to an embodiment of the present invention;
FIG. 9 is a DC voltage waveform during the operation of the DC energy consuming device under the condition of receiving end AC system failure when the system surplus power is 550MW according to an embodiment of the present invention;
fig. 10 is a dc voltage waveform during the operation of the dc energy consuming device when the receiving ac system fails when the system surplus power is 100MW according to an embodiment of the present invention.
Detailed Description
The present invention is described in detail with reference to specific embodiments in order to enable those skilled in the art to better understand the technical solutions of the present invention. It should be understood, however, that the detailed description is provided for purposes of illustration only and should not be construed to limit the invention. In describing the present invention, it is to be understood that the terminology used is for the purpose of description only and is not intended to be indicative or implied of relative importance.
Aiming at the problems that switching spikes frequently appear in a direct current energy consumption device in the prior art, the direct current voltage control effect is greatly reduced, and related electrical equipment is frequently impacted, the invention provides a grouping centralized direct current energy consumption device, a control method and a readable medium for optimizing direct current voltage control. The invention will be explained in detail below by way of example with reference to the accompanying drawings.
Example one
As shown in fig. 1, the present embodiment discloses a grouped centralized dc energy dissipation device for optimizing dc voltage control, the centralized dc energy dissipation device is connected between a dc positive electrode and a dc negative electrode, and includes an upper group and a lower group, which are symmetric to each other, where the upper group and the lower group both include a resistor and a plurality of energy dissipation modules, the number of the energy dissipation modules in the upper group and the lower group in fig. 1 is n, which are represented as SM1, SM2, and … SMn, each energy dissipation module is connected in series and is connected in series with the resistor, the upper group and the lower group are connected in parallel with a capacitor, and the connection point of the upper group and the lower group is grounded. The energy consumption module comprises a P-type field effect transistor and a diode connected with the P-type field effect transistor in an anti-parallel mode.
In the prior art, the centralized direct current energy consumption device does not comprise a capacitor connected in parallel, and the current of the energy consumption branch circuit cannot suddenly change because the current of the reactors connected to the two sides of the energy consumption branch circuit cannot suddenly change. At the moment of the input of the energy consumption resistor, the current of the energy consumption branch is still 0, but the equivalent resistance of the energy consumption branch is already changed
Figure 895393DEST_PATH_IMAGE002
The voltage between the two ends of the capacitor is suddenly reduced to form a downward input peak; at the moment of cutting off the energy consumption resistor, the current of the energy consumption branch circuit is still the energy consumption current, but the equivalent resistance of the energy consumption branch circuit is changed from R to R
Figure 393239DEST_PATH_IMAGE002
Therefore, the voltage between the terminals thereof suddenly increases, so that the direct current voltage presents an upward cut-off peak.
For the centralized dc energy dissipation device including the external capacitive branch in this embodiment, although the current of the inductive branch at both sides cannot change suddenly, the current of the parallel capacitive branch can be changed by charging/discharging the capacitor, so as to adjust the instantaneous current of the energy dissipation branch. At the moment of the input of the energy consumption resistor, the parallel capacitor discharges to the energy consumption resistor, so that the branch current of the energy consumption resistor is not maintained to be 0 any more, even if the equivalent resistance of the energy consumption branch is changed from the equivalent resistance
Figure 991711DEST_PATH_IMAGE002
When the voltage is changed into R, the voltage between the ends of the R can not drop suddenly, but can be kept unchanged instantly under the voltage stabilizing effect of the parallel capacitor, so that the input peak of the direct current voltage is restrained; at the moment of cutting off the energy consumption resistor, surplus power charges the parallel capacitor, so that the current of the branch circuit of the energy consumption resistor is instantaneously changed into 0, namely the equivalent resistance of the branch circuit of the energy consumption resistor is changed from R to R
Figure 274925DEST_PATH_IMAGE002
The voltage between the terminals will not suddenly increase, but will be in parallelThe capacitor is instantaneously kept unchanged under the voltage stabilization effect, so that the cut-out peak of the direct current voltage is inhibited.
For non-grouped centralized direct current energy dissipation devices, when the energy dissipation resistor is put into use, the power of the energy dissipation branch circuit isP N The discharge power of the capacitor isP N -△PIn which a isPRepresenting system surplus power; when the energy-consuming resistor is cut off, the power of the energy-consuming branch circuit is 0, and the discharge power of the capacitor is deltaP. Its steady state DC voltage fluctuation
Figure 815496DEST_PATH_IMAGE003
Maximum value of (c):
Figure 551371DEST_PATH_IMAGE004
wherein, U is steady-state direct current voltage, C is equivalent capacitance, and T is unit carrier period.
For the grouped centralized dc energy dissipation device in this embodiment, when two energy dissipation modules are both put into operation, the power of the energy dissipation branch isP N The discharge power of the capacitor isP N -△P(ii) a When two sets of energy consuming modules are cut off, the power of the energy consuming branch circuit is 0, and the discharge power of the capacitor is deltaP(ii) a When one set of energy consumption module is put into and the other set of energy consumption module is cut out quickly, the power of the energy consumption branch is 1/2P N If ΔP<1/2P N The capacitor discharge power at this time is 1/2P N -△PIf ΔP>1/2P N Then the capacitor charging power is delta at this timeP-1/2P N If ΔP=1/2P N The capacitor has no charge and discharge power at this time. Its steady state DC voltage fluctuation
Figure 219113DEST_PATH_IMAGE003
The maximum value of (c) is:
Figure 356833DEST_PATH_IMAGE005
。
it can be seen that the dc voltage fluctuation of the grouped centralized dc energy consuming device in this embodiment is only 1/4 of the maximum steady-state dc voltage fluctuation of the non-grouped centralized dc energy consuming device, and the dc voltage fluctuation is greatly reduced.
Example two
Based on the same inventive concept, this embodiment discloses a method for controlling a grouped centralized dc energy consumption device for optimizing dc voltage control, where the grouped centralized dc energy consumption device is used, as shown in fig. 2, and includes the following steps:
s1, based on the direct-current voltage reference value, generating a duty ratio a of the energy consumption module input through proportional integral control; fig. 3 and fig. 4 are schematic diagrams of carriers and duty ratios in the upper group and the lower group of centralized dc energy consuming devices, respectively, in this embodiment. The duty ratio a is defined as the proportion of the input time of the energy consumption resistor in a unit period. In this embodiment, the carrier is a triangular carrier, and the higher the actual value of the dc voltage is, the larger the surplus power is, and the larger the duty ratio a is.
S2, in the enabling period of the direct current energy consumption device, the phase difference of the carrier wave of the upper and lower energy consumption modules is 180 degrees, the upper and lower limit values of the triangular carrier wave are 1 and 0 respectively, and the frequency of the triangular carrier wave is determined according to the switching frequency of the energy consumption modules.
And S3, comparing the duty ratio a generated in the step S1 with the triangular carrier waves of the upper and lower groups of energy consumption modules to generate the on or off instruction of the energy consumption modules. When the duty ratio a is larger than the carrier wave, the energy consumption modules of all the sub-modules in the corresponding group are conducted, and the energy consumption modules are quickly put into use; and when the duty ratio a is smaller than the carrier wave, turning off the energy consumption modules of all the sub-modules in the corresponding group to enable the energy consumption modules to exit quickly.
For non-grouped centralized direct current energy dissipation devices, when the energy dissipation resistor is put into use, the power of the energy dissipation branch circuit isP N The discharge power of the capacitor isP N -△PIn which a isPRepresenting system surplus power; when the energy dissipation resistor is cut out, the power of the energy dissipation branch is 0, and the discharge power of the capacitor is deltaP. In order to ensure the stability of DC voltage, the average power of the energy-consuming branch in unit carrier period T should be in accordance with the systemTotal surplus power deltaPEqual, so the on-time of the energy consuming resistor in the unit period T is DeltaP/P N *T. Therefore, in the unit carrier period T, the discharge energy and the charge energy of the capacitor are respectively:
Figure 68306DEST_PATH_IMAGE006
therefore, in the unit carrier period T, the discharging energy and the charging energy of the capacitor are equal, so that the direct-current voltage can be maintained stable, and the maximum fluctuation range of the direct-current voltage can be calculated accordingly. Assuming a steady state DC voltage fluctuation range of
Figure 557056DEST_PATH_IMAGE007
And the system equivalent capacitance is C, then:
Figure 762910DEST_PATH_IMAGE008
therefore, the steady-state DC voltage fluctuates
Figure 755136DEST_PATH_IMAGE003
The expression of (c) is as follows:
Figure 653822DEST_PATH_IMAGE009
since the delta is more than or equal to 0P≤P N Thus, when ΔP =1/2 P N While obtaining steady-state DC voltage fluctuation
Figure 613557DEST_PATH_IMAGE003
Maximum value of (d):
Figure 357522DEST_PATH_IMAGE010
for the grouping centralized direct current energy consumption device, when two groups of energy consumption resistors are switched on, the power of the energy consumption branch isP N The discharge power of the capacitor isP N -△P(ii) a When two groups of energy dissipation resistors are cut off, the power of the energy dissipation branch circuit is 0, and the discharge power of the capacitor is deltaP(ii) a When one group of energy consumption resistors is switched in and the other group of energy consumption resistors is switched out, the power of the energy consumption branch is 1/2P N If ΔP<1/2P N The discharge power of the capacitor is 1/2P N -△PIf ΔP>1/2P N Then the capacitor charging power is delta at this timeP-1/2P N If ΔP=1/2P N The capacitor has no charge and discharge power at this time.
In combination with the control method of the present embodiment, steady-state DC voltage fluctuation is further analyzed
Figure 469835DEST_PATH_IMAGE003
。
The triangular carrier wave equation of the upper and lower groups of direct current energy consumption devices in a unit period [0, T ] is as follows:
Figure 273842DEST_PATH_IMAGE011
as shown in fig. 3, two intersecting moments of the carrier and the duty ratio of the upper group of dc energy consuming devices are:
Figure 720873DEST_PATH_IMAGE012
as shown in fig. 4, the time when the carrier of the following dc energy consuming devices intersects with the duty ratio is:
Figure 268529DEST_PATH_IMAGE013
to ensure the stability of the DC voltage, the available duty ratio a = DeltaP/P N 。
As shown in FIG. 5, if 0≤△P<1/2P N Then, 0≤a<1/2, at this timeIs provided with
Figure 235348DEST_PATH_IMAGE014
。
In that
Figure 475837DEST_PATH_IMAGE015
In the period, one group of energy consumption resistors are switched in, the other group of energy consumption resistors are switched out, and the discharge power of the capacitor is 1/2P N -△P。
In that
Figure 144584DEST_PATH_IMAGE016
In the period, two groups of energy dissipation resistors are cut out simultaneously, and the discharge power of the capacitor is deltaP。
Further considering the cyclicity of the carrier, it can be known that the continuous charging/discharging energy of the capacitor in a unit carrier period is:
Figure 761510DEST_PATH_IMAGE017
Figure 582836DEST_PATH_IMAGE018
this gives:
Figure 994226DEST_PATH_IMAGE019
therefore, the expression for the steady state dc voltage fluctuation is as follows:
Figure 150269DEST_PATH_IMAGE020
when a =0.25 of the total weight of the composition,
Figure 39728DEST_PATH_IMAGE021
。
as shown in FIG. 6, if ΔP=1/2P N Then a =1/2, at this time
Figure 246718DEST_PATH_IMAGE022
At any moment, one group of energy consumption resistors is switched in, the other group of energy consumption resistors is switched out, and the capacitor has no charge and discharge power, so that the theoretical value of steady-state direct-current voltage fluctuation is 0.
As shown in fig. 7, if 1/2P N <△P≤P N Then 1/2<a is less than or equal to 1, in this case
Figure 829009DEST_PATH_IMAGE023
。
In that
Figure 223082DEST_PATH_IMAGE024
In the period, one group of energy dissipation resistors is switched in, the other group of energy dissipation resistors is switched out, and the charging power of the capacitor is deltaP-1/2P N ；
In that
Figure 165499DEST_PATH_IMAGE025
In the period, two sets of energy dissipation resistors are simultaneously put into use, and the discharge power of the capacitor isP N -△P。
Further considering the cyclicity of the carrier, it can be known that the continuous charging/discharging energy of the capacitor in a unit carrier period is:
Figure 695837DEST_PATH_IMAGE026
Figure 714609DEST_PATH_IMAGE027
this gives:
Figure 595977DEST_PATH_IMAGE028
therefore, the expression of the steady-state dc voltage fluctuation is as follows:
Figure 342085DEST_PATH_IMAGE029
when a =0.75, the ratio of a =0.75,
Figure 992509DEST_PATH_IMAGE030
。
therefore, the maximum value of the steady-state dc voltage fluctuation of the grouped centralized dc energy consumption devices is:
Figure 651024DEST_PATH_IMAGE030
，
the fluctuation of the direct current voltage is only 1/4 of the maximum value of the steady-state direct current voltage fluctuation of the non-grouped centralized direct current energy consumption device, and the direct current voltage fluctuation is greatly reduced.
EXAMPLE III
In order to further verify the effectiveness and feasibility of the scheme of the invention, the device and the method in the first embodiment and the second embodiment are verified through a specific embodiment.
The open sea wind power flexible direct current output system model with rated direct current voltage of +/-400 kV and rated capacity of 1100MW is built in PSCAD software, the grouped centralized direct current energy consumption device in the first embodiment is configured, the enabling criterion of the direct current energy consumption device is set to be that the direct current voltage exceeds 1.1pu, the exit criterion is that the direct current voltage is lower than 0.97pu, and the direct current voltage reference value is 1.02pu, and the enabling criterion and the exit criterion are respectively used for verifying the direct current voltage control effect of the grouped centralized direct current energy consumption device.
Fig. 8, fig. 9, and fig. 10 are dc voltage waveforms during the operation of the dc energy consuming device when the receiving ac system fault occurs when the system surplus power is 1100MW, 550MV, and 100MV, respectively, in this embodiment. As shown in fig. 8-10, when a fault occurs in the receiving-end ac power grid under different surplus power of the system, the dc energy dissipation device can quickly stabilize the dc voltage near the reference value, there is no switching spike of the dc voltage at the moment of switching, and the steady-state fluctuation amplitude of the dc voltage is small, so that the dc voltage control effect is good.
The embodiment shows that the grouped centralized direct-current energy consumption device in the first embodiment can effectively solve the problem of large direct-current voltage switching peak of the centralized direct-current energy consumption device through the external capacitor branch, and effectively reduce the steady-state fluctuation range of direct-current voltage during the action of the centralized direct-current energy consumption device by adopting a grouped arrangement structure and a grouped control strategy, so that the direct-current voltage control effect of the centralized direct-current energy consumption device is obviously optimized, and the grouped centralized direct-current energy consumption device has great practical value and wide application prospect in the field of sending far-sea wind power through flexible direct current.
EXAMPLE III
Based on the same inventive concept, the present embodiment discloses a computer-readable storage medium, on which a computer program is stored, the computer program being executed by a processor to implement the method for controlling any one of the above described grouped centralized dc energy consuming devices for optimizing dc voltage control.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims. The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (10)

1. A grouping centralized direct current energy consumption device for optimizing direct current voltage control is characterized in that the centralized direct current energy consumption device is connected between a direct current positive electrode and a direct current negative electrode and comprises an upper group and a lower group which are symmetrical, the upper group and the lower group both comprise a resistor and a plurality of energy consumption modules, the energy consumption modules are connected in series and are connected with the resistor in series, the upper group and the lower group are respectively connected with a capacitor in parallel, and the upper group and the lower group are grounded through the connection positions of the upper group and the lower group.
2. The device of claim 1, wherein the energy dissipation module comprises a PFET and a diode connected in anti-parallel therewith.
3. The grouped and centralized dc energy dissipation device for optimizing dc voltage control according to claim 2, wherein the capacitors are connected in parallel to discharge the capacitors to the energy dissipation modules at the moment the energy dissipation modules are turned on, so as to suppress dc voltage input spikes; and at the moment when the energy consumption module is switched out, surplus power charges the parallel capacitor, so that the peak is restrained from being switched out by the direct-current voltage.
4. The grouped and centralized dc energy dissipation device for optimizing dc voltage control as claimed in claim 3, wherein when both sets of energy dissipation modules are turned on, the branch energy dissipation means has a power ofP N The discharge power of the capacitor isP N -△P(ii) a When two sets of energy consuming modules are cut off, the power of the energy consuming branch circuit is 0, and the discharge power of the capacitor is deltaP(ii) a When one set of energy consumption module is put into and the other set of energy consumption module is cut out quickly, the power of the energy consumption branch is 1/2P N If ΔP<1/2P N The capacitor discharge power at this time is 1/2P N -△PIf ΔP>1/2P N Then the capacitor charging power is ΔP-1/2P N If ΔP=1/2P N The capacitor has no charge and discharge power at this time.
5. The grouped concentrated dc energy consumption device for optimizing dc voltage control according to claim 4, wherein the maximum value of the steady-state dc voltage fluctuation of the grouped concentrated dc energy consumption device is:
Figure 263450DEST_PATH_IMAGE001
wherein, U is a steady-state direct-current voltage, C is an equivalent capacitance, and T is a unit carrier period.
6. A method for controlling a group centralized dc consumer for optimizing dc voltage control, wherein the group centralized dc consumer of any one of claims 1 to 5 is used, and the method comprises the following steps:
generating a duty ratio a of the energy consumption module fast input through proportional integral control based on the direct-current voltage reference value;
in the enabling period of the direct current energy consumption device, the phase difference of the carriers of the upper and lower groups of energy consumption modules is 180 degrees;
and comparing the duty ratio a with the carriers of the upper and lower groups of energy consumption modules to generate a switching-on or switching-off instruction of the energy consumption module.
7. The method for controlling a grouped centralized direct-current energy consumption device according to claim 6, wherein when the duty ratio a is greater than the carrier, the energy consumption modules of all the sub-modules in the corresponding group are turned on, and the energy consumption modules are put into operation; and when the duty ratio a is smaller than the carrier wave, the energy consumption modules of all the sub-modules in the corresponding group are turned off, so that the energy consumption modules are quickly exited.
8. The method for controlling a grouped and centralized dc consumer according to claim 6, wherein the higher the actual value of the dc voltage, the larger the duty cycle a.
9. The method as claimed in claim 6, wherein the carrier is a triangular carrier, the upper and lower limits of the triangular carrier are 1 and 0, respectively, and the frequency of the triangular carrier is determined according to the switching frequency of the energy consumption module.
10. A computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, which computer program is executable by a processor to implement the method for controlling an optimized dc voltage controlled, grouped, centralized dc consumer according to any of the claims 6-9.
CN202210712131.7A 2022-06-22 2022-06-22 Grouping centralized direct current energy consumption device for optimizing direct current voltage control and control method Active CN114792971B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210712131.7A CN114792971B (en) 2022-06-22 2022-06-22 Grouping centralized direct current energy consumption device for optimizing direct current voltage control and control method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210712131.7A CN114792971B (en) 2022-06-22 2022-06-22 Grouping centralized direct current energy consumption device for optimizing direct current voltage control and control method

Publications (2)

Publication Number Publication Date
CN114792971A true CN114792971A (en) 2022-07-26
CN114792971B CN114792971B (en) 2022-09-13

Family

ID=82463700

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210712131.7A Active CN114792971B (en) 2022-06-22 2022-06-22 Grouping centralized direct current energy consumption device for optimizing direct current voltage control and control method

Country Status (1)

Country Link
CN (1) CN114792971B (en)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108539796A (en) * 2018-05-31 2018-09-14 华中科技大学 A kind of fault traversing and energy dissipation control method of the bipolar soft straight power grid of wind-powered electricity generation
CN109586327A (en) * 2018-11-07 2019-04-05 詹长江 A kind of energy absorption device and its control method
CN109950890A (en) * 2019-03-25 2019-06-28 华中科技大学 A kind of full-control type energy-consuming device
CN210380245U (en) * 2019-05-21 2020-04-21 清华大学 Direct current energy consumption system and electric power system
WO2020082660A1 (en) * 2018-10-22 2020-04-30 南京南瑞继保电气有限公司 Direct current energy dissipation apparatus and control method therefor
CN111525531A (en) * 2020-04-16 2020-08-11 清华大学 Direct current energy dissipation device containing interelectrode capacitance
WO2021212987A1 (en) * 2020-04-21 2021-10-28 南京南瑞继保电气有限公司 Fault redundancy control method for modular direct current energy consumption apparatus
CN113852113A (en) * 2021-09-14 2021-12-28 广东电网有限责任公司阳江供电局 Modular distributed resistance energy consumption device, control method and storage medium

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108539796A (en) * 2018-05-31 2018-09-14 华中科技大学 A kind of fault traversing and energy dissipation control method of the bipolar soft straight power grid of wind-powered electricity generation
WO2020082660A1 (en) * 2018-10-22 2020-04-30 南京南瑞继保电气有限公司 Direct current energy dissipation apparatus and control method therefor
CN109586327A (en) * 2018-11-07 2019-04-05 詹长江 A kind of energy absorption device and its control method
CN109950890A (en) * 2019-03-25 2019-06-28 华中科技大学 A kind of full-control type energy-consuming device
CN210380245U (en) * 2019-05-21 2020-04-21 清华大学 Direct current energy consumption system and electric power system
CN111525531A (en) * 2020-04-16 2020-08-11 清华大学 Direct current energy dissipation device containing interelectrode capacitance
WO2021212987A1 (en) * 2020-04-21 2021-10-28 南京南瑞继保电气有限公司 Fault redundancy control method for modular direct current energy consumption apparatus
CN113852113A (en) * 2021-09-14 2021-12-28 广东电网有限责任公司阳江供电局 Modular distributed resistance energy consumption device, control method and storage medium

Also Published As

Publication number Publication date
CN114792971B (en) 2022-09-13

Similar Documents

Publication Publication Date Title
Mosaad et al. Application of superconductors to improve the performance of DFIG-based WECS
CN101950973A (en) Double-fed wind generating set control system and stable control method
CN102891497A (en) Method for starting ultra-weak receiving-end high-voltage direct-current power transmission system by using static synchronous compensation
CN103178548A (en) Symmetrical fault ride-through control method of double-fed wind generator set
Wu et al. An adaptive phase-locked loop for the transient stability enhancement of grid-connected voltage source converters
Wang et al. DC electric springs with DC/DC converters
Wu et al. Modeling and control of multi-terminal HVDC with offshore wind farm integration and DC chopper based protection strategies
Hillers et al. Low-voltage fault ride through of the modular multilevel converter in a battery energy storage system connected directly to the medium voltage grid
Zhang et al. Coordinated utilization of adaptive inertia control and virtual impedance regulation for transient performance increase of VSG under different faults
Sedighizadeh et al. Coordinated optimization and control of SFCL and SMES for mitigation of SSR using HBB-BC algorithm in a fuzzy framework
CN114792971B (en) Grouping centralized direct current energy consumption device for optimizing direct current voltage control and control method
Gupta Integration Challenges of Wind Power on Power System Grid A Review
Makolo et al. Fault ride through technique for dfig-based wind turbines under grid three-phase faults
CN113013917B (en) Hybrid phase synchronization controller and control method for power electronic converter
Arasteh et al. Fault ride through capability of grid forming wind turbines: A comparison of control schemes
Bharadwaj et al. E-STATCOM (energy storage+ STATCOM): a solution to integrate large-scale wind farms into the grid at medium and high power levels
Subburaj et al. Battery and wind system in weak/strong grid analysis
Emamalipour et al. THD minimization in variable input cascaded H-bridge multi-level inverters via state table
Kim et al. A seamless transfer algorithm based on frequency detection and feedforward control method in distributed generation system
He-feng et al. Optimized operation mode of coordination between the flywheel energy storage and generators for pulsed loads in micro-grid
Biswal et al. An enhanced control methodology for LVRT Improvement of DFIG under fault condition
Jassim et al. Dual Droop-Based Controllers for Hybrid Microgrid with Photovoltaic and Wind Turbine Distributed Generators
Mahrouch et al. LVRT Control for Wind Farm Based on Permanent Magnet Synchronous Generator Connected into the Grid
Liu et al. Research on LVRT Control Combination Strategy of PV Station
Ni et al. A model predictive control of SMES-battery hybrid energy storage system for voltage regulation in DC microgrids

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
CB03 Change of inventor or designer information
CB03 Change of inventor or designer information

Inventor after: Guo Mingqun

Inventor after: Teng Shangfu

Inventor after: Zhao Zheng

Inventor after: Tian Yuanyuan

Inventor after: Li Ming

Inventor after: Zhang Tao

Inventor after: Xue Yinglin

Inventor after: Li Tan

Inventor after: Huang Caowei

Inventor after: Luo Shuhan

Inventor before: Guo Mingqun

Inventor before: Teng Shangfu

Inventor before: Zhao Zheng

Inventor before: Tian Yuanyuan

Inventor before: Li Ming

Inventor before: Zhang Tao

Inventor before: Xue Yinglin

Inventor before: Li Tan

Inventor before: Huang Caowei

Inventor before: Luo Shuhan