Wideband oscillation coordination control method, device and system for new energy sending-out area

Abstract

The invention belongs to the field of power system automation, and discloses a broadband oscillation coordination control method, device and system for a new energy sending-out area. Comprising the following steps: deploying a control master station in a hub substation of a new energy delivery area, and deploying a control substation in a new energy pooling station; an emergency control measure set is screened out according to the oscillation modal power of the pooling station outgoing line of each control substation; selecting and switching the new energy grid connection line with the maximum oscillation power amplitude ratio in the screened set; and controlling in turns, and adjusting the control range according to the control effect. According to the invention, accurate positioning and rapid coordination control of an oscillation source in a new energy sending area can be realized, unit overcut caused by disordered action of protection equipment of each station after oscillation is avoided, and safe and stable operation of a power grid is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of power systems and automation thereof, and specifically relates to a method, device and system for coordinated control of broadband oscillation in a renewable energy transmission area. Background Art

[0002] With the increasing proportion of installed capacity of new energy sources such as wind power and photovoltaics, as well as the rapid development of flexible direct current transmission and power electronic loads, the power system is gradually showing a high proportion of power electronic characteristics.

[0003] In new power systems, broadband oscillations are very likely to occur between new energy units and flexible DC and new energy units. Traditional oscillation suppression methods are difficult to adapt to the complex and changeable oscillation scenarios brought about by large-scale new energy access. In recent years, oscillations caused by new energy have frequently spread to the main grid, seriously threatening the safe and stable operation of the power grid.

[0004] At present, the control of broadband oscillation in engineering mostly adopts local control mode, and there is a lack of unified coordinated control for large-scale new energy transmission areas, which easily causes disordered operation of equipment between plants and stations and over-cutting of units. At the same time, the existing control strategy lacks theoretical support and the control means are extensive, resulting in a high cost of oscillation control.

[0005] Prior art document 1 (CN 115528701 A) discloses a coordinated control method and system for improving the broadband oscillation stability of a power grid. It is worth noting that in the technical solution of prior art document 1: 1) the control master station and the control substation realize broadband information and control instruction interaction through a dispatching data network, and the real-time and reliability of the control are difficult to guarantee, which is not suitable for emergency control of broadband oscillations; 2) the coordinated control strategy mechanism is unclear, and there is a risk of over-cutting new energy; 3) the implementation method is complex, and the project implementation is difficult.

[0006] Prior art document 2 (CN 115693706 A) discloses a method and device for controlling wide-band oscillation of a power grid integrating multi-feature information. It is worth noting that in the technical solution of prior art document 2: 1) the control method lacks coordination, and regional oscillation may cause disorderly power switching of multiple plant stations, which may worsen the oscillation and even bring other safety and stability problems; 2) the control strategy mechanism is unclear, and there is a risk of over-cutting new energy; 3) the sequence resistance of the oscillation mode is difficult to measure accurately, and the method is difficult to implement. Summary of the invention

[0007] The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art and provide a method, device and system for coordinated control of broadband oscillation in a new energy transmission area.

[0008] To achieve the above object, the present invention adopts the following technical solutions: A first aspect of the present invention provides a method for coordinated control of broadband oscillation in a new energy transmission area, comprising:

[0009] Step 1: Monitor the oscillation characteristic quantity of the regional power grid tie line to determine whether there is oscillation in the regional power grid tie line. If there is no oscillation, continue to monitor the regional power grid tie line; if there is oscillation, collect the voltage and current signals of the outgoing line of the collection station and the new energy grid-connected line to obtain the fundamental wave characteristic quantity and oscillation characteristic quantity of the line;

[0010] Step 2: Calculate the ratio of the oscillation modal power of the outgoing line of the collection station and the oscillation power amplitude of the new energy grid-connected line;

[0011] Step 3: Select the emergency control measures set S1 and S2 according to the direction and magnitude of the oscillation modal power of the outgoing line of the collection station;

[0012] Step 4: Eliminate the new energy grid-connected lines that are out of service or have no oscillation in the emergency control measures set S1 and S2;

[0013] Step 5: Sort the new energy grid-connected lines in the emergency control measure sets S1 and S2 respectively according to the oscillation power amplitude ratio from large to small, and sort the new energy grid-connected lines in the emergency control measure set S1 as a whole before the emergency control measure set S2;

[0014] Step 6: Cut off the new energy grid-connected line with the highest ranking, and determine the control scope of subsequent rounds based on the control effect of this round;

[0015] Step 7: Repeat the above steps until the oscillation is under control.

[0016] Preferably, in step 2, calculating the oscillation modal power of the outgoing line of the collection station includes:

[0017] When the oscillation voltage amplitude is lower than the set ratio of the rated voltage or the oscillation current amplitude is lower than the set ratio of the rated current, the formula (2) is used to calculate the oscillation modal power of the outgoing line of the collection station; otherwise, the formula (1) is used to calculate the oscillation modal power of the outgoing line of the collection station:

[0018]

[0019] in:

[0020] P m_WF0 (t) is the oscillation mode power of the outgoing line of the collection station m,

[0021] U m_WF (t) is the oscillation voltage amplitude of the outgoing line of the collection station m,

[0022] I m_WF (t) is the oscillating current amplitude of the outgoing line of the collection station m,

[0023] θ m_WF is the phase angle difference between the oscillating voltage and oscillating current of the outgoing line of the collection station m,

[0024] P m_DC (t) is the DC component of the power outgoing from the collection station m,

[0025] P m_0 (t) is the fundamental power of the outgoing line from the collection station m.

[0026] Preferably, in step 2, the calculation of the oscillation power amplitude ratio of the new energy grid-connected line is expressed by the following formula (3):

[0027]

[0028] in,

[0029] P mn_WF_REL (t) is the oscillation power amplitude ratio of the new energy grid-connected line n at the collection station m,

[0030] P mn_WF (t) is the oscillation power amplitude of the new energy grid-connected line n at the collection station m,

[0031] P mn_0 (t) is the fundamental power of the new energy grid-connected line n at the collection station m.

[0032] Preferably, step 3 includes: setting an oscillation modal power threshold, if the oscillation modal power of the outgoing line of the collection station is positive and greater than the oscillation modal power threshold, the new energy grid-connected line of the collection station is included in the emergency control measures set S1; if the oscillation modal power of the outgoing line of the collection station is negative and the absolute value is greater than the oscillation modal power threshold, the new energy grid-connected line of the collection station is included in the emergency control measures set S2; otherwise, the new energy grid-connected line of the collection station is not included in the emergency control measures set.

[0033] Preferably, step 4 includes: setting a threshold for determining the presence of oscillation, if the oscillation amplitude ratio of the new energy grid-connected line exceeds the threshold for determining the presence of oscillation, determining that the new energy grid-connected line has oscillation; otherwise, determining that the new energy grid-connected line does not have oscillation.

[0034] Preferably, step 6 includes: determining whether the oscillation of the regional power grid interconnection line is suppressed after the new energy grid-connected line is cut off, and dynamically adjusting the control range according to the oscillation suppression situation, specifically including: if the oscillation is suppressed, the new energy collection station selected in this round is still allowed to be included in the subsequent round of emergency control measures set; otherwise, the new energy collection station selected in this round is no longer included in the subsequent round of emergency control measures set.

[0035] Preferably, determining whether the oscillation is suppressed in step 6 includes:

[0036] If the oscillation amplitude of the regional power grid interconnection line monitored by the new energy hub substation decreases after the current round of new energy grid-connected lines are cut off, it is judged that the oscillation is suppressed, otherwise it is judged that the oscillation is not suppressed.

[0037] A second aspect of the present invention provides a wide-band oscillation coordination control device for a new energy transmission area, comprising:

[0038] The data acquisition and analysis module is used to collect the voltage and current signals of the outgoing lines of the collection station and the new energy grid-connected lines, and obtain the fundamental wave characteristic quantity and oscillation characteristic quantity of the lines;

[0039] A calculation module, used to calculate the oscillation modal power of the outgoing line of the collection station and the oscillation power amplitude ratio of the new energy grid-connected line;

[0040] A screening module is used to screen out emergency control measures sets S1 and S2 according to the power of the outgoing oscillation mode of the collection station;

[0041] A sorting module is used to sort the new energy grid-connected lines in the sets S1 and S2 in descending order according to the oscillation power amplitude ratio;

[0042] A judgment module is used to judge whether there is oscillation in the new energy, whether the oscillation is suppressed after control, and whether the new energy collection station selected in this round will participate in the subsequent rounds of control;

[0043] The communication module is used to achieve millisecond-level communication between devices in different plants and stations.

[0044] The third aspect of the present invention provides a new energy transmission area broadband oscillation coordination control system, and the operation of the new energy transmission area broadband oscillation coordination control method comprises:

[0045] The control master station is deployed in the hub substation in the renewable energy delivery area;

[0046] Control substation, deployed at the new energy collection station;

[0047] The communication medium is used to provide a physical link for communication between the control master station and the control substation, and to achieve millisecond-level communication between plant and station devices.

[0048] The fourth aspect of the present invention provides a computer-readable storage medium, which stores a computer program, characterized in that when the computer program is executed by a processor, it runs the method for coordinated control of wide-band oscillation in a new energy transmission area.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] The present invention provides a method, device and system for coordinated control of broadband oscillation in a new energy transmission area. By calculating the oscillation modal power of the outgoing line of a collection station and the oscillation power amplitude ratio of the new energy grid-connected line, emergency control measure sets S1 and S2 are screened out according to the direction and size of the oscillation modal power of the outgoing line of the collection station, and the new energy grid-connected line is preferentially cut off in the order of the oscillation power amplitude ratio from large to small in the set S1, so as to realize accurate positioning and rapid coordinated control of the oscillation source in the new energy transmission area.

[0051] The present invention solves the problem of disorderly operation of multiple plants and over-cut units caused by local control of broadband oscillation in the renewable energy transmission area, and realizes accurate and rapid positioning of the oscillation area through oscillation modal power, providing a theoretical basis for oscillation control. The present invention can be applied to power systems with large-scale renewable energy access, realize precise and coordinated control of regional broadband oscillations, and effectively guarantee the safe and stable operation of new power systems in complex environments.

[0052] More specifically, compared with the aforementioned prior art documents, the beneficial technical effects achieved by the present invention include at least:

[0053] 1) The control master station is deployed in the hub substation in the renewable energy transmission area, and communicates with the control substation through a millisecond-level communication network. The real-time and reliability of data and control command interaction are high, reducing the risk of mis-cutting renewable energy, and is suitable for emergency control of broadband oscillations; 2) Considering the problem that the oscillation modal power is difficult to measure directly and accurately, the direct method and indirect method are used to calculate the oscillation modal power respectively; 3) The coordinated control strategy has a clear mechanism, and locates the oscillation source based on the oscillation energy flow direction to avoid multiple plants and stations from cutting off units at the same time, which can reduce the amount of renewable energy cutting and thus reduce the cost of oscillation control; 4) The control range is dynamically adjusted according to the control effect of each round, and the optimal control combination can be screened to avoid the continuous divergence of oscillations due to the failure of control measures. 5) The implementation method is simple and clear, and easy to implement in engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A flow chart of a method for coordinated control of wide-band oscillation in a new energy transmission area provided in an embodiment of the present invention.

[0055] Figure 2 This is a schematic diagram of the network topology structure of a certain area provided in Example 1 of the present invention.

[0056] Figure 3 This is a schematic diagram of the screening of the emergency control measures set provided in Example 1 of the present invention.

[0057] Figure 4 This is a schematic diagram of the structure of the broadband oscillation coordination control device for the new energy transmission area provided in Example 2 of the present invention.

[0058] Figure 5This is a schematic diagram of the structure of a wide-band oscillation coordination control system for a new energy transmission area provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0059] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0060] The present invention will be further described below in conjunction with the accompanying drawings.

[0061] Example 1

[0062] There is at least one new energy collection station in the controlled regional power grid. Each new energy collection station is connected to multiple new energy stations through the new energy grid-connected line of the collection station. Each new energy collection station is connected to the first substation through the outgoing line. The first substation is connected to the second substation through the regional power grid interconnection line to send the new energy power generation out of the regional power grid.

[0063] See also Figure 1 In embodiment 1 of the present invention, a method for coordinated control of broadband oscillation in a new energy transmission area is provided, comprising the following steps:

[0064] Step 1: Monitor the oscillation characteristic quantity of the regional power grid interconnection line to determine whether there is oscillation in the regional power grid interconnection line. If there is no oscillation, continue to monitor the regional power grid interconnection line; if there is oscillation, collect the voltage and current signals of the collection station outgoing line and the new energy grid-connected line, and obtain the fundamental wave characteristic quantity and oscillation characteristic quantity of the line through fast Fourier analysis, and continue to step 2.

[0065] In a preferred but non-limiting embodiment of the present invention, step 1 specifically comprises:

[0066] Step 11: Collect the three-phase voltage and three-phase current signals of the outgoing line of the collection station and the new energy grid-connected line;

[0067] Step 12: Perform fast Fourier analysis to obtain fundamental wave characteristics of the outgoing line of the collection station, including fundamental wave power, fundamental wave voltage, fundamental wave current, fundamental wave frequency and other information of the line;

[0068] Step 13: Perform fast Fourier analysis to obtain the oscillation characteristics of the outgoing line of the collection station, including power DC component, oscillation power, oscillation voltage, oscillation current, oscillation frequency and other information.

[0069] Step 2: Calculate the ratio of the oscillation modal power of the outgoing line of the collection station and the oscillation power amplitude of the renewable energy grid-connected line.

[0070] In a preferred but non-limiting embodiment of the present invention, step 2 specifically comprises:

[0071] Step 21: The oscillation modal power of the outgoing line of the collection station is calculated by formula (1) or formula (2); when the oscillation voltage amplitude is lower than 1% of the rated voltage or the oscillation current amplitude is lower than 1% of the rated current, that is, the measurement error of the oscillation voltage phase angle or the oscillation current phase angle is large, the oscillation modal power is calculated by formula (2) to reduce the calculation error; otherwise, the oscillation modal power is calculated by formula (1):

[0072]

[0073] P m_WF0 (t) = P m_DC (t)-P m_0 (t) (2)

[0074] in:

[0075] P m_WF0 (t) is the oscillation mode power of the outgoing line of the collection station m,

[0076] U m_WF (t) is the oscillation voltage amplitude of the outgoing line of the collection station m,

[0077] I m_WF (t) is the oscillating current amplitude of the outgoing line of the collection station m,

[0078] θ m_WF is the phase angle difference between the oscillating voltage and oscillating current of the outgoing line of the collection station m,

[0079] P m_DC (t) is the DC component of the power outgoing from the collection station m,

[0080] P m_0 (t) is the fundamental power of the outgoing line from the collection station m.

[0081] Step 22: The oscillation power amplitude ratio of the new energy grid-connected line is calculated by formula (3):

[0082]

[0083] in,

[0084] P mn_WF_REL (t) is the oscillation power amplitude ratio of the new energy grid-connected line n at the collection station m,

[0085] P mn_WF (t) is the oscillation power amplitude of the new energy grid-connected line n at the collection station m,

[0086] P mn_0 (t) is the fundamental power of the new energy grid-connected line n at the collection station m.

[0087] Step 3: Select the emergency control measures sets S1 and S2 according to the direction and size of the oscillation modal power of the outgoing line of the collection station.

[0088] In a preferred but non-limiting embodiment of the present invention, the screening of the emergency control measures sets S1 and S2 in step 3 specifically includes:

[0089] Step 31: setting an oscillation mode power threshold, where the oscillation mode power threshold is a device parameter, i.e., a fixed value of a control master station or a control substation;

[0090] Step 32: If the oscillation modal power of the outgoing line of the collection station is positive and greater than the oscillation modal power threshold, the new energy grid-connected line of the collection station is included in the emergency control measures set S1; if the oscillation modal power of the outgoing line of the collection station is negative and the absolute value is greater than the oscillation modal power threshold, the new energy grid-connected line of the collection station is included in the emergency control measures set S2; otherwise, the new energy grid-connected line of the collection station is not included in the emergency control measures set.

[0091] Step 4: Eliminate the new energy grid-connected lines that are out of service or have no oscillation in the emergency control measure sets S1 and S2.

[0092] In a preferred but non-limiting embodiment of the present invention, the step 4 of determining whether there is oscillation in the new energy grid-connected line specifically includes:

[0093] Step 41: setting a threshold for judging the existence of oscillation, wherein the threshold for judging the existence of oscillation is a device parameter, that is, a fixed value of the control master station or the control substation;

[0094] Step 42: If the oscillation amplitude ratio of the new energy grid-connected line exceeds the threshold for judging the existence of oscillation, it is judged that the new energy grid-connected line has oscillation; otherwise, it is judged that the new energy grid-connected line does not have oscillation.

[0095] Step 5: Sort the new energy grid-connected lines in sets S1 and S2 respectively according to the oscillation power amplitude ratio from large to small, and sort the new energy grid-connected lines in set S1 as a whole before set S2.

[0096] In a preferred but non-limiting embodiment of the present invention, step 5 specifically comprises:

[0097] Step 51: sorting the new energy grid-connected lines in the sets S1 and S2 respectively in descending order of oscillation power amplitude ratio;

[0098] Step 52: Arrange the new energy grid-connected lines of set S1 as a whole before set S2.

[0099] It is worth noting that, as a prominent substantive feature of the present invention and one of the significant advances it brings to the prior art, the present invention adopts a method of judging the power direction of the oscillation mode of the outgoing line of the collection station in combination with the amplitude ratio. If it is in the sending direction, it means that the new energy transmits oscillating energy to the power grid, which can be considered as the oscillation source and should be given priority for removal; if it is in the receiving direction, it means that the new energy absorbs oscillating energy from the power grid, and it will also be effective after removal.

[0100] Step 6: Cut off the new energy grid-connected line with the highest ranking, and determine the control scope of subsequent rounds based on the control effect of this round.

[0101] In a preferred but non-limiting embodiment of the present invention, step 6: determining the control range of subsequent rounds according to the control effect of the current round, specifically includes:

[0102] Step 61: determine whether the oscillation of the regional power grid tie line is suppressed after the new energy grid-connected line is removed, and dynamically adjust the control range according to the oscillation suppression situation;

[0103] Step 62: If the oscillation is suppressed, the new energy collection station selected in this round is still allowed to be included in the emergency control measures set of subsequent rounds; otherwise, the new energy collection station selected in this round is no longer included in the emergency control measures set of subsequent rounds.

[0104] In step 6, determining whether the oscillation is suppressed specifically includes:

[0105] If the oscillation amplitude of the regional power grid interconnection line monitored by the new energy hub substation decreases after the new energy is cut off, it is judged that the oscillation is suppressed, otherwise it is judged that the oscillation is not suppressed.

[0106] It is worth noting that as a prominent substantive feature of the present invention and one of the significant advances it brings to the prior art, the present invention dynamically adjusts the control range according to the control effect of each round, can screen out the optimal control combination, achieve rapid control of oscillations at a lower control cost, and avoid continued divergence of oscillations due to failure of control measures.

[0107] Step 7: Repeat the above steps until the oscillation is under control.

[0108] The application process of the wide-band oscillation coordinated control method for new energy transmission area provided in this embodiment specifically involves the following steps:

[0109] In summary, the broadband oscillation coordinated control method for the new energy transmission area of ​​the present invention calculates the oscillation modal power of the collection station outgoing line and the oscillation power amplitude ratio of the new energy grid-connected line, and selects the emergency control measure sets S1 and S2 according to the direction and size of the outgoing line oscillation modal power, and preferentially cuts off the new energy grid-connected line in the set S1 in the order of the oscillation power amplitude ratio from large to small, and determines the subsequent control range according to the control effect of this round. This method can realize the accurate positioning and rapid coordinated control of the oscillation source in the new energy transmission area, avoid the disorderly action of the protection equipment of each station after the oscillation occurs and over-cut the unit, and ensure the safe and stable operation of the power grid.

[0110] In order to more clearly introduce the outstanding essential features of the present invention and the significant progress it brings to the prior art, the contents involved in the above embodiment are explained in conjunction with a preferred embodiment below.

[0111] Figure 2 The schematic diagram of the network topology structure of a certain area in which the present invention is applied. Taking a certain domestic renewable energy transmission regional power grid as an example, the strategy of the present invention is introduced and explained. 500kV renewable energy collection stations A, B, C, and D are connected to three renewable energy stations, marked as A1, A2, A3, B1, B2, B3, C1, C2, C3, D1, D2, and D3 respectively; the 500kV renewable energy collection station is transmitted through 1000kV substations E and F. The outgoing lines of the renewable energy collection station are marked as L A , L B , L C , L D , the new energy grid-connected lines of the collection station are marked as L A1 , L A2 , L A3 , L B1 , L B2 , L B3 , L C1 , L C2 , L C3 , L D1 , L D2 , L D3 , the regional power grid tie line is marked as L E .

[0112] Collect regional power grid tie line L E The three-phase voltage and three-phase current are analyzed by fast Fourier transform to obtain the line oscillation voltage U WF , oscillating current I WF , Oscillation power P WF The amplitude and phase angle of the tie line are determined, and whether there is oscillation is determined according to the tie line oscillation characteristic quantity. If it is determined that the tie line has oscillation, the subsequent process is executed, otherwise the subsequent process is not executed.

[0113] Collect the three-phase voltage and three-phase current of the outgoing line of the new energy collection station, and perform fast Fourier analysis to obtain the line oscillation voltage U WF , oscillating current I WF , Oscillation power P WF The amplitude and phase angle of the fundamental power P0 and the DC component of the power P DC size.

[0114] The oscillation modal power P of each new energy collection station outgoing line is calculated according to the formula WF0 When the amplitude of the oscillating voltage of the new energy collection station is lower than 1% of the rated voltage or the amplitude of the oscillating current is lower than 1% of the rated current, the formula P is used. m_WF0 (t) = P m_DC (t)-P m_0 (t) Calculate the oscillation mode power, otherwise use the formula Calculate the modal powers of oscillation.

[0115] Table 1 Oscillation mode power table of each new energy collection station

[0116] line LA LB LC LD Oscillation modal power (MW) -3.2 -1.0 2.8 3.1

[0117] Collect the three-phase voltage and three-phase current of the new energy grid-connected line of the collection station, and perform fast Fourier analysis to obtain the line fundamental power P0 and oscillation power P WF size.

[0118] According to the formula The oscillation power amplitude ratio P of the new energy grid-connected lines of each collection station is calculated WF_REL .

[0119] Table 2 Ratio of oscillation power amplitude of new energy grid-connected lines at each collection station

[0120] line LA1 LA2 LA3 LB1 LB2 LB3 Oscillation power amplitude ratio (%) 3.2 0 1.8 1.5 0 2.0 line LC1 LC2 LC3 LD1 LD2 LD3 Oscillation power amplitude ratio (%) 1.0 1.7 0.6 1.2 2.8 2.3

[0121] The oscillation modal power P of each new energy collection station outgoing line m_WF0 In turn, the device parameter "oscillation mode power threshold P mk_WF0 "Compare. If P m_WF0 ≥P mk_WF0 , then the new energy grid-connected line of the collection station is included in the emergency control measures set S1; if -P m_WF0 ≥P mk_WF0 , then the new energy grid-connected line of the collection station is included in the emergency control measures set S2.

[0122] Device parameter "Oscillation mode power threshold P mk_WF0 ” is set to 2.5MW, then the emergency control measure set S1 includes the new energy grid-connected lines L of the collection stations C and D C1 , L C2 , L C3, L D1 , L D2 , L D3 , the emergency control measure set S2 includes the new energy grid-connected line L of the collection station A A1 , L A2 , L A3 , see Figure 3 .

[0123] The device parameter "Oscillation threshold" is set to 1.5%, and the line L without oscillation in the set S1 is eliminated. C1 , L C3 , L D1 , determine that there are 3 renewable energy grid-connected lines that can be switched in set S1, namely L C2 , L D2 , L D3 Eliminate the out-of-service line L in set S2 A2 , determine that there are 2 renewable energy grid-connected lines that can be switched in set S2, namely L A1 , L A3 The selected new energy grid-connected lines participating in the emergency control include L C2 , L D2 , L D3 , L A1 , L A3 , the remaining new energy grid-connected lines do not participate in emergency control.

[0124] The renewable energy grid-connected lines in set S1 are sorted from large to small according to the oscillation power amplitude ratio as the preferred removal objects; the renewable energy grid-connected lines in set S2 are sorted from large to small according to the oscillation power amplitude ratio as the backup removal objects; the sorting results are shown in the following table.

[0125] Table 3 Ranking of grid-connected lines for various new energy sources

[0126]

[0127] According to the above table, the new energy grid-connected line L should be disconnected first D2 , after cutting off the new energy grid-connected line, determine the change in the oscillation amplitude of the interconnection line; if the oscillation is effectively controlled, end this control process; if the oscillation is not effectively controlled, further determine whether the oscillation amplitude of the interconnection line after control is less than the oscillation amplitude before control, if so, the new energy grid-connected line of the collection station D is still allowed to be included in the subsequent round of emergency control measures, otherwise the new energy grid-connected line of the collection station D is no longer included in the subsequent round of emergency control measures.

[0128] Repeat the above process until the regional power grid tie line L E The oscillation is effectively controlled.

[0129] Example 2

[0130] See also Figure 4 In Embodiment 2 of the present invention, a wide-band oscillation coordination control device for a new energy transmission area is provided, comprising the following modules:

[0131] The data acquisition and analysis module is used to collect the voltage and current signals of the outgoing lines of the collection station and the new energy grid-connected lines, and obtain the fundamental wave characteristic quantity and oscillation characteristic quantity of the lines;

[0132] A calculation module, used to calculate the oscillation modal power of the outgoing line of the collection station and the oscillation power amplitude ratio of the new energy grid-connected line;

[0133] A screening module is used to screen out emergency control measures sets S1 and S2 according to the power of the outgoing oscillation mode of the collection station;

[0134] A sorting module is used to sort the new energy grid-connected lines in the sets S1 and S2 in descending order according to the oscillation power amplitude ratio;

[0135] A judgment module is used to judge whether there is oscillation in the new energy, whether the oscillation is suppressed after control, and whether the new energy collection station selected in this round will participate in the subsequent rounds of control;

[0136] The communication module is used to achieve millisecond-level communication between devices in different plants and stations.

[0137] Example 3

[0138] See also Figure 5 In Embodiment 3 of the present invention, a wide-band oscillation coordination control system for a new energy transmission area is provided, and the operation of the wide-band oscillation coordination control method for a new energy transmission area includes:

[0139] The control master station is deployed in the hub substation in the renewable energy delivery area;

[0140] Control substation, deployed at new energy collection station or new energy site;

[0141] The communication medium is used to provide a physical link for communication between the control master station and the control substation, and to achieve millisecond-level communication between plant and station devices.

[0142] Example 4

[0143] Embodiment 4 of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, wherein the computer program, when executed by a processor, implements the method for coordinated control of wide-band oscillation in a new energy transmission area.

[0144] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for coordinated control of broadband oscillation in a renewable energy transmission area. It is characterized in that include: Step 1: Monitor the oscillation characteristic quantity of the regional power grid tie line to determine whether there is oscillation in the regional power grid tie line. If there is no oscillation, continue to monitor the regional power grid tie line; if there is oscillation, collect the voltage and current signals of the outgoing line of the collection station and the new energy grid-connected line to obtain the fundamental wave characteristic quantity and oscillation characteristic quantity of the line; Step 2: Calculate the ratio of the oscillation modal power of the outgoing line of the collection station and the oscillation power amplitude of the new energy grid-connected line; Step 3: Select the emergency control measures set S1 and S2 according to the direction and magnitude of the oscillation modal power of the outgoing line of the collection station; Step 4: Eliminate the new energy grid-connected lines that are out of service or have no oscillation in the emergency control measures set S1 and S2; Step 5: Sort the new energy grid-connected lines in the emergency control measure sets S1 and S2 respectively according to the oscillation power amplitude ratio from large to small, and sort the new energy grid-connected lines in the emergency control measure set S1 as a whole before the emergency control measure set S2; Step 6: Cut off the new energy grid-connected line with the highest ranking, and determine the control scope of subsequent rounds based on the control effect of this round; Step 7: Repeat the above steps until the oscillation is under control.

2. According to claim 1, a method for coordinated control of broadband oscillation in a new energy transmission area, Features: In the step 2, calculating the oscillation modal power of the outgoing line of the collection station includes: When the oscillation voltage amplitude is lower than the set ratio of the rated voltage or the oscillation current amplitude is lower than the set ratio of the rated current, the formula (2) is used to calculate the oscillation modal power of the outgoing line of the collection station; otherwise, the formula (1) is used to calculate the oscillation modal power of the outgoing line of the collection station: P m_WF0 (t)=P m_DC (t)-P m_0 (t) (2) in: P m_WF0 (t) is the oscillation mode power of the outgoing line of the collection station m, U m_WF (t) is the oscillation voltage amplitude of the outgoing line of the collection station m, I m_WF (t) is the oscillating current amplitude of the outgoing line of the collection station m, θ m_WF is the phase angle difference between the oscillating voltage and oscillating current of the outgoing line of the collection station m, P m_DC (t) is the DC component of the power outgoing from the collection station m, P m_0 (t) is the fundamental power of the outgoing line from the collection station m.

3. A method for coordinated control of broadband oscillation in a new energy transmission area according to claim 1 or 2, Features: In step 2, the oscillation power amplitude ratio of the new energy grid-connected line is calculated using the following formula (3): in, P mn_WF_REL (t) is the oscillation power amplitude ratio of the new energy grid-connected line n at the collection station m, P mn_WF (t) is the oscillation power amplitude of the new energy grid-connected line n at the collection station m, P mn_0 (t) is the fundamental power of the new energy grid-connected line n at the collection station m.

4. A method for coordinated control of wideband oscillation in a new energy transmission area according to claim 1, Features: Step 3 includes: setting an oscillation modal power threshold. If the oscillation modal power of the outgoing line of the collection station is positive and greater than the oscillation modal power threshold, the new energy grid-connected line of the collection station is included in the emergency control measures set S1; if the oscillation modal power of the outgoing line of the collection station is negative and the absolute value is greater than the oscillation modal power threshold, the new energy grid-connected line of the collection station is included in the emergency control measures set S2; otherwise, the new energy grid-connected line of the collection station is not included in the emergency control measures set.

5. A method for coordinated control of broadband oscillation in a new energy transmission area according to claim 1 or 4, Features: Step 4 includes: setting a threshold for determining the presence of oscillation, and if the oscillation amplitude ratio of the renewable energy grid-connected line exceeds the threshold for determining the presence of oscillation, determining that the renewable energy grid-connected line has oscillation; otherwise, determining that the renewable energy grid-connected line does not have oscillation.

6. A method for coordinated control of wideband oscillation in a new energy transmission area according to claim 1, Features: Step 6 includes: determining whether the oscillation of the regional power grid interconnection line is suppressed after the new energy grid-connected line is cut off, and dynamically adjusting the control range according to the oscillation suppression situation, specifically including: if the oscillation is suppressed, the new energy collection station selected in this round is still allowed to be included in the subsequent round of emergency control measures set; otherwise, the new energy collection station selected in this round is no longer included in the subsequent round of emergency control measures set.

7. A method for coordinated control of broadband oscillation in a new energy transmission area according to claim 6, Features: Determining whether the oscillation is suppressed in step 6 includes: If the oscillation amplitude of the regional power grid interconnection line monitored by the new energy hub substation decreases after the current round of new energy grid-connected lines are cut off, it is judged that the oscillation is suppressed, otherwise it is judged that the oscillation is not suppressed.

8. A wide-band oscillation coordination control device for new energy transmission areas, It is characterized in that include: The data acquisition and analysis module is used to collect the voltage and current signals of the outgoing lines of the collection station and the new energy grid-connected lines, and obtain the fundamental wave characteristic quantity and oscillation characteristic quantity of the lines; A calculation module, used to calculate the oscillation modal power of the outgoing line of the collection station and the oscillation power amplitude ratio of the new energy grid-connected line; A screening module is used to screen out emergency control measures sets S1 and S2 according to the power of the outgoing oscillation mode of the collection station; A sorting module is used to sort the new energy grid-connected lines in the sets S1 and S2 in descending order according to the oscillation power amplitude ratio; A judgment module is used to judge whether there is oscillation in the new energy, whether the oscillation is suppressed after control, and whether the new energy collection station selected in this round will participate in the subsequent rounds of control; The communication module is used to achieve millisecond-level communication between devices in different plants and stations.

9. A wideband oscillation coordination control system for a new energy transmission area, running a wideband oscillation coordination control method for a new energy transmission area according to any one of claims 1 to 7, It is characterized in that include: The control master station is deployed in the hub substation in the renewable energy delivery area; Control substation, deployed at the new energy collection station; The communication medium is used to provide a physical link for communication between the control master station and the control substation, and to achieve millisecond-level communication between plant and station devices.

10. A computer-readable storage medium storing a computer program. Its characteristics are: When the computer program is executed by the processor, it runs a method for coordinated control of wide-band oscillation in a new energy transmission area according to any one of claims 1-7.

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