New energy unit short-circuit current control measure effective period identification method and system

Abstract

The invention discloses a new energy unit short-circuit current control measure effective time period identification method and system, and the method comprises the steps: calibrating the short-circuit current of a power grid, and screening an operation mode in which the short-circuit current of a bus is higher than a safety standard in a target time period as a to-be-controlled mode; respectively adjusting the overcurrent coefficient and the constant value current multiple of the effective new energy unit to obtain a plurality of corresponding adjustment schemes, and obtaining a plurality of candidate limitation measures corresponding to the effective new energy unit set; applying the candidate limiting measures to the first to-be-controlled mode in the unchecked modes one by one, and determining an effective limiting time period according to whether the bus short-circuit current is higher than a safety standard and whether the transient voltage passes checking; and combining all the effective limiting time periods to obtain all the effective time periods of the short-circuit current control measures of the new energy unit in the target time period and corresponding candidate limiting measures. By adopting the technical scheme, which time periods can adjust and limit the short-circuit current through the new energy unit control parameters in the future can be identified.

Description

Technical Field

[0001] The present invention relates to the field of power grid control technology, and in particular to a method and system for identifying an effective period of short-circuit current control measures for a new energy generator set. Background Art

[0002] With the acceleration of the construction of new power systems, the grid-connected capacity of new energy units continues to increase. During faults, new energy units will provide short-circuit currents and reactive power through short-circuit currents, thereby supporting the voltage at the grid connection point. The short-circuit current provided by new energy units includes active current components and reactive current components. The reactive current component is close in phase with the short-circuit current component of the grid-connected AC system, and has a significant impact on the short-circuit current at the fault point. The key control parameters that affect the reactive current component of new energy units include overcurrent coefficients and fixed current multiples. Therefore, short-circuit current limitation can be performed by adjusting the control parameters of new energy units.

[0003] Conventional short-circuit current control measures have a great impact on the power grid, but the short-circuit current control effect is obvious. The short-circuit current control measures of new energy units have a small impact on the power grid, but the short-circuit current control ability is small. Therefore, for the way that the short-circuit current exceeds the standard slightly, the short-circuit current is limited by adjusting the control parameters of the new energy units. For the way that the short-circuit current exceeds the standard significantly, the short-circuit current is limited by the control measures combining conventional short-circuit current control measures with the adjustment of the parameters of the new energy units. Some conventional measures require the preparation of scheduling plans in advance. Therefore, it is necessary to identify which time periods in the future time period can limit the short-circuit current through the adjustment of the control parameters of the new energy units, and which time periods need to be limited by the control measures combining conventional short-circuit current control measures with the adjustment of the control parameters of the new energy units, so as to provide technical support for the scheduling and operation personnel to plan conventional measures in advance.

[0004] However, there is little research at home and abroad on how to identify which time periods in the future can limit short-circuit current by adjusting the control parameters of new energy units. Summary of the invention

[0005] Purpose of the invention: The present invention provides a method and system for identifying effective time periods of short-circuit current control measures for new energy units, aiming to solve the technical problem in the prior art that there is no effective method to identify which time periods in the future can limit short-circuit current by adjusting control parameters of new energy units.

[0006] Technical solution: The present invention provides a method for identifying effective time periods of short-circuit current control measures for new energy units, including: obtaining multiple operating modes of a future target time period of a power grid; calibrating the short-circuit current of a bus in a power grid under each operating mode, screening out operating modes in which the bus short-circuit current is higher than the safety standard during the target time period, and using the screened operating modes as modes to be controlled; for the modes to be controlled, screening corresponding effective new energy units to obtain a set of effective new energy units; executing a restriction measure generation step for the effective new energy unit set to obtain multiple candidate restriction measures corresponding to the effective new energy unit set; executing an identification step to check the mode to be controlled, and determining a parameter adjustment range of the effective new energy unit set, as well as an effective restriction time period; executing a restriction measure generation step within the parameter adjustment range of the effective new energy unit set, again obtaining multiple candidate restriction measures corresponding to the effective new energy unit set, and executing an identification step until all modes to be controlled are identified; combining all effective restriction time periods determined in the identification step to obtain all effective time periods of short-circuit current control measures for new energy units within the target time period, and the corresponding candidate restriction measures.

[0007] Specifically, the electrical distance between the new energy unit and the busbar whose short-circuit current is higher than the safety standard is calculated, and the new energy units whose electrical distance is less than the standard distance are screened as candidate new energy units; the short-circuit current sensitivity of the candidate new energy units to the busbar whose short-circuit current is higher than the safety standard is calculated, and the candidate new energy units whose short-circuit current sensitivity is higher than the corresponding sensitivity threshold are screened as effective new energy units; the short-circuit current sensitivity includes overcurrent coefficient sensitivity and fixed current multiple sensitivity.

[0008] Specifically, the overcurrent coefficient sensitivity is calculated using the following formula:

[0009] ΔI j i,k =I j (k i +Δk,I i,qmax )-I j (k i ,I i,qmax ),

[0010] Among them, ΔI j i,k It represents the sensitivity of the overcurrent coefficient of the i-th renewable energy unit to the overcurrent coefficient of the j-th busbar, I j (k i +Δk,I i,qmax ) represents the short-circuit current of the jth bus after the overcurrent coefficient is perturbed, I j (k i ,I i,qmax ) represents the short-circuit current of the jth bus before perturbation, k irepresents the overcurrent coefficient of the i-th renewable energy unit, Δk represents the perturbation step of the overcurrent coefficient, I i,qmax Indicates the constant current multiple of the i-th renewable energy unit.

[0011] Specifically, the constant current multiple sensitivity is calculated using the following formula:

[0012] ΔI j i,q =I j (k i ,I i,qmax +ΔI i,qmax )-I j (k i ,I i,qmax ),

[0013] Among them, ΔI j i,q It represents the sensitivity of the fixed current multiple of the i-th renewable energy unit to the fixed current multiple of the j-th busbar, I j (k i ,I i,qmax +ΔI i,qmax ) represents the short-circuit current of the jth bus after the constant current multiple is perturbed, ΔI i,qmax Indicates the perturbation step size of the constant current multiple.

[0014] Specifically, the restriction measure generation step includes: adjusting the overcurrent coefficient and the fixed current multiple of the effective new energy unit respectively to obtain multiple corresponding adjustment schemes, combining the adjustment schemes of each new energy unit in the effective new energy unit set, and obtaining multiple candidate restriction measures corresponding to the effective new energy unit set; determining the value range of the overcurrent coefficient and the fixed current multiple of the effective new energy unit; keeping the overcurrent coefficient unchanged, taking values ​​one by one within the value range of the fixed current multiple with a first perturbation step, and obtaining multiple fixed current multiple parameter adjustment schemes; keeping the fixed current multiple unchanged, taking values ​​one by one within the value range of the overcurrent coefficient with a second perturbation step, and obtaining multiple overcurrent coefficient parameter adjustment schemes; combining the obtained fixed current multiple parameter adjustment scheme and overcurrent coefficient parameter adjustment scheme to obtain multiple adjustment schemes for the effective new energy unit.

[0015] Specifically, the identification step includes: applying candidate restriction measures one by one to the first control mode in the unchecked control mode, according to whether the bus short-circuit current is higher than the safety standard and whether the transient voltage verification is passed.

[0016] Specifically, if there are candidate restriction measures that control the short-circuit current of the busbar to be no higher than the safety standard and the transient voltage check passes, the corresponding candidate restriction measures will be used as effective restriction measures, and the parameter adjustment range of the effective new energy unit set will be determined based on the parameter values ​​of all effective restriction measures. At the same time, the implementation period of the corresponding control method will be used as the effective restriction period.

[0017] Specifically, if there is no candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard, or there is a candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard but the transient voltage check fails, the parameter adjustment range of the current candidate restriction measure will be used, and the implementation period of the corresponding control method will be set as an invalid restriction period.

[0018] The present invention also provides a new energy unit short-circuit current control measure effective time period identification system, comprising: an operation mode acquisition unit, a short-circuit identification unit, an effective unit screening unit, a restriction measure generation unit, an effective restriction period identification unit, a restriction measure regeneration unit and a synthesis unit, wherein: the operation mode acquisition unit is used to obtain multiple operation modes of the future target period of the power grid; the short-circuit identification unit is used to calibrate the short-circuit current of the bus in the power grid under each operation mode, and screen out the operation mode in which the bus short-circuit current is higher than the safety standard during the target period, and use the screened operation mode as the to-be-controlled mode; the effective unit screening unit is used to screen the corresponding effective new energy units for the to-be-controlled mode to obtain a set of effective new energy units; the restriction measure generation unit is used to screen the effective new energy units The group set executes the restriction measure generation step to obtain multiple candidate restriction measures corresponding to the effective new energy unit set; the effective restriction period identification unit is used to execute the identification step to check the control mode to be controlled, and determine the parameter adjustment range of the effective new energy unit set, and the effective restriction period; the restriction measure regeneration unit is used to execute the restriction measure generation step within the parameter adjustment range of the effective new energy unit set, and obtain multiple candidate restriction measures corresponding to the effective new energy unit set again, and transfer to the effective restriction period identification unit to execute the identification step until all the control modes are identified; the synthesis unit is used to combine all the effective restriction periods determined in the identification step to obtain all effective periods of the short-circuit current control measures of the new energy unit within the target period, and the corresponding candidate restriction measures.

[0019] Specifically, the effective unit screening unit is used to calculate the electrical distance between the new energy unit and the busbar with a short-circuit current higher than the safety standard, and screen the new energy units with an electrical distance less than the standard distance as candidate new energy units; calculate the short-circuit current sensitivity of the candidate new energy unit to the busbar with a short-circuit current higher than the safety standard, and screen the candidate new energy units with a short-circuit current sensitivity higher than the corresponding sensitivity threshold as effective new energy units; the short-circuit current sensitivity includes overcurrent coefficient sensitivity and fixed current multiple sensitivity.

[0020] Specifically, the effective unit screening unit is used to calculate the overcurrent coefficient sensitivity using the following formula:

[0021] ΔI j i,k =I j (k i +Δk,I i,qmax )-I j (k i ,I i,qmax ),

[0022] Among them, ΔI j i,k It represents the sensitivity of the overcurrent coefficient of the i-th renewable energy unit to the overcurrent coefficient of the j-th busbar, I j (k i +Δk,I i,qmax ) represents the short-circuit current of the jth bus after the overcurrent coefficient is perturbed, I j (k i ,I i,qmax ) represents the short-circuit current of the jth bus before perturbation, k i represents the overcurrent coefficient of the i-th renewable energy unit, Δk represents the perturbation step of the overcurrent coefficient, I i,qmax Indicates the constant current multiple of the i-th renewable energy unit.

[0023] Specifically, the effective unit screening unit is used to calculate the constant current multiple sensitivity using the following formula:

[0024] ΔI j i,q =I j (k i ,I i,qmax +ΔI i,qmax )-I j (k i ,I i,qmax ),

[0025] Among them, ΔI j i,q It represents the sensitivity of the fixed current multiple of the i-th renewable energy unit to the fixed current multiple of the j-th busbar, I j(k i ,I i,qmax +ΔI i,qmax ) represents the short-circuit current of the jth bus after the constant current multiple is perturbed, I j (k i ,I i,qmax ) represents the short-circuit current of the jth bus before perturbation, k i represents the overcurrent coefficient of the i-th renewable energy unit, I i,qmax Indicates the fixed current multiple of the i-th renewable energy unit, ΔI i,qmax Indicates the perturbation step size of the constant current multiple.

[0026] Specifically, the restriction measure generation unit is used to execute the restriction measure generation step, which includes: adjusting the overcurrent coefficient and the fixed current multiple of the effective new energy unit respectively to obtain multiple corresponding adjustment schemes, combining the adjustment schemes of each new energy unit in the effective new energy unit set, and obtaining multiple candidate restriction measures corresponding to the effective new energy unit set; adjusting the overcurrent coefficient and the fixed current multiple of the effective new energy unit respectively to obtain multiple corresponding adjustment schemes, including: determining the value range of the overcurrent coefficient and the fixed current multiple of the effective new energy unit; keeping the overcurrent coefficient unchanged, taking values ​​one by one within the value range of the fixed current multiple with a first perturbation step, and obtaining multiple fixed current multiple parameter adjustment schemes; keeping the fixed current multiple unchanged, taking values ​​one by one within the value range of the overcurrent coefficient with a second perturbation step, and obtaining multiple overcurrent coefficient parameter adjustment schemes; combining the obtained fixed current multiple parameter adjustment scheme and overcurrent coefficient parameter adjustment scheme to obtain multiple adjustment schemes for the effective new energy unit.

[0027] Specifically, the effective restriction period identification unit is used to perform an identification step, which includes: applying the candidate restriction measures one by one to the first control mode in the unverified control mode, based on whether the bus short-circuit current is higher than the safety standard and whether the transient voltage verification is passed.

[0028] Specifically, the effective restriction period identification unit is used to use the corresponding candidate restriction measure as the effective restriction measure if there is a candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard and the transient voltage check passes, and determine the parameter adjustment range of the effective new energy unit set according to the parameter values ​​of all effective restriction measures, and at the same time use the implementation period of the corresponding control method as the effective restriction period.

[0029] Specifically, the effective restriction period identification unit is used to use the parameter adjustment range of the current candidate restriction measure if there is no candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard, or if there is a candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard but the transient voltage check fails, and at the same time, the corresponding implementation period of the control method is used as an invalid restriction period.

[0030] The present invention also provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program executable by the processor, and when the computer program is executed by the processor, any method for identifying the effective period of short-circuit current control measures for new energy units provided by the present invention is executed.

[0031] The present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of any method for identifying an effective period of short-circuit current control measures for new energy generator sets provided by the present invention are implemented.

[0032] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: identifying which time periods in the future can limit short-circuit current by adjusting the control parameters of the new energy units, and providing corresponding new energy unit control parameter adjustment plans. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic diagram of a method for identifying an effective period of short-circuit current control measures for a new energy generator set provided by the present invention. DETAILED DESCRIPTION

[0034] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0035] In the specific implementation, the key control parameters that affect the reactive current component of the new energy unit include the overcurrent coefficient and the fixed current multiple. The simulation results show that by reducing the overcurrent coefficient and the fixed current multiple of the new energy unit, the short-circuit current contributed by the new energy unit to the power grid can be reduced, thereby reducing the short-circuit current of the system fault bus and expanding the short-circuit current control means.

[0036] See also Figure 1 , which is a schematic diagram of the method for identifying the effective time period of short-circuit current control measures for new energy units provided by the present invention.

[0037] In the embodiment of the present invention, multiple operation modes of the power grid in the future target period are obtained.

[0038] In specific implementation, the operation mode of the power grid can be comprehensively determined through the power grid's power generation plan, DC dispatching plan, power equipment maintenance plan, load distribution and new energy power generation distribution. The operation mode of the future target period, for example, all the operation modes of the power grid in the next 4 hours.

[0039] In an embodiment of the present invention, the short-circuit current of the bus in the power grid under various operating modes is calibrated, and an operating mode in which the bus short-circuit current in the target time period is higher than the safety standard (which can be set according to the actual application scenario) is screened out, and the screened operating mode is used as the mode to be controlled.

[0040] In the specific implementation, after obtaining the grid operation mode, the short-circuit current after a bus short-circuit fault occurs under the corresponding operation mode can be simulated and calibrated. If the short-circuit current of one or more busbars is higher than the safety standard, it indicates that the corresponding grid operation mode needs to be controlled to limit the size of the short-circuit current.

[0041] In the embodiment of the present invention, for the mode to be controlled, the corresponding effective new energy units are screened to obtain a set of effective new energy units.

[0042] In an embodiment of the present invention, the electrical distance between the new energy units in the candidate measure set and the busbar whose short-circuit current is higher than the safety standard is calculated, and the new energy units whose electrical distance is less than the standard distance are screened as candidate new energy units; the short-circuit current sensitivity of the candidate new energy units to the busbar whose short-circuit current is higher than the safety standard is calculated, and the candidate new energy units whose short-circuit current sensitivity is higher than the corresponding sensitivity threshold (which can be set according to the actual application scenario) are screened as effective new energy units; the short-circuit current sensitivity includes overcurrent coefficient sensitivity and fixed current multiple sensitivity.

[0043] In specific implementation, the electrical distance and short-circuit current sensitivity both characterize the degree of influence of changes in the control parameters of the new energy unit on the busbar with excessive short-circuit current. The shorter the electrical distance and the higher the short-circuit current sensitivity, the greater the influence of changes in the control parameters of the new energy unit on the busbar with excessive short-circuit current, that is, the stronger the limiting effect on the short-circuit current. Therefore, screening is carried out based on these two indicators.

[0044] In the embodiment of the present invention, the sensitivity of the overcurrent coefficient is calculated using the following formula:

[0045] ΔI j i,k =I j (k i +Δk,I i,qmax )-I j (k i ,I i,qmax ),

[0046] Among them, ΔIj i,k It represents the sensitivity of the overcurrent coefficient of the i-th renewable energy unit to the overcurrent coefficient of the j-th busbar,

[0047] I j (k i +Δk,I i,qmax ) represents the short-circuit current of the jth bus after the overcurrent coefficient is perturbed, I j (k i ,I i,qmax ) represents the short-circuit current of the jth bus before the perturbation (overcurrent coefficient or fixed current multiple), k i represents the overcurrent coefficient of the i-th renewable energy unit, Δk represents the perturbation step of the overcurrent coefficient (which can be set according to the actual application scenario), I i,qmax Indicates the constant current multiple of the i-th renewable energy unit.

[0048] In the embodiment of the present invention, ΔI j i,q =I j (k i ,I i,qmax +ΔI i,qmax )-I j (k i ,I i,qmax ),

[0049] Among them, ΔI j i,q It represents the sensitivity of the fixed current multiple of the i-th renewable energy unit to the fixed current multiple of the j-th busbar, I j (k i ,I i,qmax +ΔI i,qmax ) represents the short-circuit current of the jth bus after the constant current multiple is perturbed, ΔI i,qmax Indicates the perturbation step size of the fixed current multiple (can be set according to the actual application scenario).

[0050] In an embodiment of the present invention, a restriction measure generation step is performed on a set of effective new energy units, and the restriction measure generation step includes: adjusting the overcurrent coefficient and the fixed current multiple of the effective new energy units respectively to obtain corresponding multiple adjustment schemes.

[0051] In an embodiment of the present invention, the value range (parameter adjustment range) of the overcurrent coefficient and the fixed current multiple of the effective new energy unit is determined; the overcurrent coefficient is kept unchanged, and values ​​are taken one by one within the value range of the fixed current multiple with a first perturbation step (for example, 0.2) to obtain A fixed current multiple parameter adjustment schemes; the fixed current multiple is kept unchanged, and values ​​are taken one by one within the value range of the overcurrent coefficient with a second perturbation step (for example, 0.3) to obtain B overcurrent coefficient parameter adjustment schemes; the obtained fixed current multiple parameter adjustment scheme and overcurrent coefficient parameter adjustment scheme are combined to obtain A+B adjustment schemes for the effective new energy unit.

[0052] In a specific implementation, for a new energy unit, the overcurrent coefficient and the fixed current multiple are both parameters to be adjusted in the present invention. One of the quantities is kept unchanged, and the other is adjusted with a fixed step size. Each step size is an adjustment plan.

[0053] In the embodiment of the present invention, the adjustment schemes of each new energy unit in the effective new energy unit set are combined to obtain a plurality of candidate restriction measures corresponding to the effective new energy unit set.

[0054] In specific implementation, an effective new energy unit may have A+B adjustment plans. By arranging and combining the adjustment plans of each new energy unit in the effective new energy unit set, all candidate restriction measures corresponding to the effective new energy unit set can be obtained. For example, there are three new energy units in the effective new energy unit set, and these three new energy units each have two adjustment plans, then the effective new energy unit set will have 2*2*2=8 candidate restriction measures.

[0055] In an embodiment of the present invention, an identification step is executed to verify the control mode, and the identification step includes: applying candidate restriction measures one by one to the first control mode in the unverified control mode (the control mode for which the identification step has not been executed), and determining the parameter adjustment range of the effective new energy unit set and the effective restriction period according to whether the bus short-circuit current is higher than the safety standard and whether the transient voltage is verified.

[0056] In the embodiment of the present invention, within the parameter adjustment range of the effective new energy unit set, the restriction measure generation step is executed, multiple candidate restriction measures corresponding to the effective new energy unit set are obtained again, and the identification step is executed until all the control modes are identified.

[0057] In a specific implementation, the candidate restriction measures are applied to the control mode to be controlled, and the control parameters of the new energy unit are adjusted according to the candidate restriction measures (usually through simulation calculation data), and the short-circuit current of the bus under the control mode to be controlled is calculated.

[0058] In an embodiment of the present invention, if there are candidate restriction measures that control the short-circuit current of the busbar to be no higher than the safety standard and the transient voltage check passes, the corresponding candidate restriction measures will be used as effective restriction measures, and the parameter adjustment range (value range) of the effective new energy unit set will be determined based on the parameter values ​​of all effective restriction measures. At the same time, the implementation period of the corresponding control method will be used as the effective restriction period.

[0059] In an embodiment of the present invention, if there is no candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard, or there is a candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard but the transient voltage check fails, the parameter adjustment range (value range) of the current candidate restriction measure will be used, and the implementation period of the corresponding control method will be set as an invalid restriction period.

[0060] In a specific implementation, for example, the range of the overcurrent coefficients of the eight generated candidate restriction measures is [0.1, 2.5], and the range of the fixed current multiple is [0.1, 1.2]. There are 16 grid operation modes in the future target period. The short-circuit current of the first to fifth modes does not exceed the standard, and the short-circuit current of the sixth to sixteenth modes exceeds the standard. The eight generated candidate restriction measures are applied to the sixth mode one by one, and the short-circuit current and transient voltage are checked. The check result is that five of the candidate restriction measures control the bus short-circuit current not higher than the safety standard and the transient voltage check passes, and the overcurrent coefficients of the five candidate restriction measures are in the range of [0.5-1.5], and the fixed current multiple is in the range of [0.3-1.0]. Then, a plurality of candidate restriction measures for the seventh operation mode are generated through the restriction measure generation step (the overcurrent coefficient is in the range of [0.5-1.5], and the fixed current multiple is in the range of [0.3-1.0]), and then the generated candidate restriction measures are applied to the seventh operation mode, and the short-circuit current and transient voltage are checked. Transient voltage check, and so on, until all the 6th to 16th operating modes are subject to candidate restriction measures and short-circuit current and transient voltage checks are performed, and the effective restriction period is identified; if the 8 generated candidate restriction measures are applied to the 6th mode one by one, and short-circuit current and transient voltage checks are performed, and the check result is that all candidate restriction measures cannot control the bus short-circuit current to be not higher than the safety standard or the transient voltage check fails, then the restriction measure generation step is still performed with the overcurrent coefficient range of [0.1,2.5] and the constant current multiple range of [0.1,1.2] as the parameter adjustment range (that is, if all candidate restriction measures in the Nth mode cannot control the bus short-circuit current to be not higher than the safety standard or the transient voltage check fails, then the parameter adjustment range in the Nth mode is used as the parameter value range of the N+1th mode), and multiple candidate restriction measures for the 7th operating mode are generated, and then the generated candidate restriction measures are applied to the 7th operating mode.

[0061] In the embodiment of the present invention, all effective time periods of the short-circuit current control measures of the new energy generator set within the target time period and the corresponding candidate (effective) restriction measures are obtained according to all effective restriction time period combinations determined in the identification step.

[0062] In a specific implementation, for example, candidate restriction measures are applied to all the 6th to 16th operating modes in which the bus short-circuit current exceeds the standard, and the short-circuit current does not exceed the standard and the transient voltage check passes for the 6th to 10th operating modes after the corresponding candidate restriction measures are applied. Then the total time period corresponding to the 6th to 10th operating modes is all the effective time period, and the candidate restriction measures that can control the short-circuit current not to exceed the standard and pass the transient voltage check are effective restriction measures.

[0063] In specific implementation, the present invention provides a method with strong operability, which identifies which time periods in the future can limit short-circuit current by adjusting the control parameters of new energy units, and provides corresponding new energy unit control parameter adjustment plans, which can limit the short-circuit current of the power grid more efficiently and conveniently.

[0064] The present invention also provides a new energy unit short-circuit current control measure effective time period identification system, comprising: an operation mode acquisition unit, a short-circuit identification unit, an effective unit screening unit, a restriction measure generation unit, an effective restriction period identification unit, a restriction measure regeneration unit and a synthesis unit, wherein: the operation mode acquisition unit is used to obtain multiple operation modes of the future target period of the power grid; the short-circuit identification unit is used to calibrate the short-circuit current of the bus in the power grid under each operation mode, and screen out the operation mode in which the bus short-circuit current is higher than the safety standard during the target period, and use the screened operation mode as the to-be-controlled mode; the effective unit screening unit is used to screen the corresponding effective new energy units for the to-be-controlled mode to obtain a set of effective new energy units; the restriction measure generation unit is used to execute the restriction measure generation step for the effective new energy unit set, and the restriction measure generation step includes: adjusting the overcurrent coefficient and the fixed current multiple of the effective new energy units respectively to obtain the corresponding multiple adjustment schemes, and adjusting the effective new energy units The adjustment schemes of each new energy unit in the unit set are combined to obtain multiple candidate restriction measures corresponding to the effective new energy unit set; the effective restriction period identification unit is used to execute the identification step to check the control mode, and the identification step includes: applying the candidate restriction measures one by one to the first control mode in the unchecked control mode, and determining the parameter adjustment range and the effective restriction period of the effective new energy unit set according to whether the bus short-circuit current is higher than the safety standard and whether the transient voltage is checked; the restriction measure regeneration unit is used to execute the restriction measure generation step within the parameter adjustment range of the effective new energy unit set, obtain multiple candidate restriction measures corresponding to the effective new energy unit set again, and transfer to the effective restriction period identification unit to execute the identification step until all the control modes are identified; the synthesis unit is used to combine all the effective restriction periods determined in the identification step to obtain all effective periods of the short-circuit current control measures of the new energy units within the target period, and the corresponding candidate restriction measures.

[0065] In an embodiment of the present invention, the effective unit screening unit is used to calculate the electrical distance between the new energy unit and the busbar whose short-circuit current is higher than the safety standard, and screen the new energy units whose electrical distance is less than the standard distance as candidate new energy units; calculate the short-circuit current sensitivity of the candidate new energy unit to the busbar whose short-circuit current is higher than the safety standard, and screen the candidate new energy units whose short-circuit current sensitivity is higher than the corresponding sensitivity threshold as effective new energy units; the short-circuit current sensitivity includes overcurrent coefficient sensitivity and fixed current multiple sensitivity.

[0066] In the embodiment of the present invention, the effective unit screening unit uses the following formula to calculate the overcurrent coefficient sensitivity:

[0067] ΔI j i,k=I j (k i +Δk,I i,qmax )-I j (k i ,I i,qmax ),

[0068] Among them, ΔI j i,k It represents the sensitivity of the overcurrent coefficient of the i-th renewable energy unit to the overcurrent coefficient of the j-th busbar, I j (k i +Δk,I i,qmax ) represents the short-circuit current of the jth bus after the overcurrent coefficient is perturbed, I j (k i ,I i,qmax ) represents the short-circuit current of the jth bus before perturbation, k i represents the overcurrent coefficient of the i-th renewable energy unit, Δk represents the perturbation step of the overcurrent coefficient, I i,qmax Indicates the constant current multiple of the i-th renewable energy unit.

[0069] In the embodiment of the present invention, the effective unit screening unit uses the following formula to calculate the constant current multiple sensitivity:

[0070] ΔI j i,q =I j (k i ,I i,qmax +ΔI i,qmax )-I j (k i ,I i,qmax ),

[0071] Among them, ΔI j i,q It represents the sensitivity of the fixed current multiple of the i-th renewable energy unit to the fixed current multiple of the j-th busbar, I j (k i ,I i,qmax +ΔI i,qmax ) represents the short-circuit current of the jth bus after the constant current multiple is perturbed, I j (k i ,I i,qmax ) represents the short-circuit current of the jth bus before perturbation, k i represents the overcurrent coefficient of the i-th renewable energy unit, I i,qmax Indicates the fixed current multiple of the i-th renewable energy unit, ΔI i,qmax Indicates the perturbation step size of the constant current multiple.

[0072] In an embodiment of the present invention, the restriction measure generation unit is used to execute the restriction measure generation step, and the restriction measure generation step includes: adjusting the overcurrent coefficient and the fixed current multiple of the effective new energy unit respectively to obtain multiple corresponding adjustment schemes, combining the adjustment schemes of each new energy unit in the effective new energy unit set, and obtaining multiple candidate restriction measures corresponding to the effective new energy unit set; the overcurrent coefficient and the fixed current multiple of the effective new energy unit are adjusted respectively to obtain multiple corresponding adjustment schemes, including: determining the value range of the overcurrent coefficient and the fixed current multiple of the effective new energy unit; keeping the overcurrent coefficient unchanged, taking values ​​one by one within the value range of the fixed current multiple with a first perturbation step size, and obtaining multiple fixed current multiple parameter adjustment schemes; keeping the fixed current multiple unchanged, taking values ​​one by one within the value range of the overcurrent coefficient with a second perturbation step size, and obtaining multiple overcurrent coefficient parameter adjustment schemes; combining the obtained fixed current multiple parameter adjustment scheme and overcurrent coefficient parameter adjustment scheme to obtain multiple adjustment schemes for the effective new energy unit.

[0073] In an embodiment of the present invention, the effective restriction period identification unit is used to perform an identification step, which includes: applying candidate restriction measures one by one to the first control mode in the unverified control mode, based on whether the bus short-circuit current is higher than the safety standard and whether the transient voltage verification is passed.

[0074] In an embodiment of the present invention, the effective restriction period identification unit is used to use the corresponding candidate restriction measure as the effective restriction measure if there is a candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard and the transient voltage check passes, and determine the parameter adjustment range of the effective new energy unit set according to the parameter values ​​of all effective restriction measures, and at the same time use the corresponding implementation period of the control method as the effective restriction period.

[0075] In an embodiment of the present invention, the effective restriction period identification unit is used to use the parameter adjustment range of the current candidate restriction measure if there is no candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard, or if there is a candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard but the transient voltage check fails, and at the same time, the corresponding implementation period of the control method is used as an invalid restriction period.

[0076] The present invention also provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program executable by the processor, and when the computer program is executed by the processor, any method for identifying the effective period of short-circuit current control measures for new energy units provided by the present invention is executed.

[0077] The present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of any method for identifying an effective period of short-circuit current control measures for new energy generator sets provided by the present invention are implemented.

[0078] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0079] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0080] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0081] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

Claims

1. A method for identifying effective time periods of short-circuit current control measures for new energy units, characterized in that: include: Obtain multiple operation modes of the power grid during future target periods; Calibrate the short-circuit current of the busbar in the power grid under various operation modes, select the operation mode in which the busbar short-circuit current is higher than the safety standard during the target period, and use the selected operation mode as the mode to be controlled; For the control mode to be controlled, the corresponding effective new energy units are screened to obtain a set of effective new energy units; Executing a restriction measure generation step on the effective new energy unit set to obtain a plurality of candidate restriction measures corresponding to the effective new energy unit set; Execute the identification step to check the control method to be controlled, determine the parameter adjustment range of the effective new energy unit set, and the effective restriction period; Within the parameter adjustment range of the effective new energy unit set, a restriction measure generation step is performed to obtain multiple candidate restriction measures corresponding to the effective new energy unit set again, and an identification step is performed until all the control modes are identified; All effective restriction time periods determined in the identification step are combined to obtain all effective time periods of short-circuit current control measures for new energy units within the target time period and corresponding candidate restriction measures.

2. The method for identifying the effective period of short-circuit current control measures for new energy units according to claim 1 is characterized in that: The screening of the corresponding effective new energy units to obtain an effective new energy unit set includes: Calculate the electrical distance between the new energy generating unit and the busbar whose short-circuit current is higher than the safety standard, and select the new energy generating units whose electrical distance is less than the standard distance as candidate new energy generating units; Calculate the short-circuit current sensitivity of the candidate new energy units to the short-circuit current higher than the safety standard bus, and screen the candidate new energy units with short-circuit current sensitivity higher than the corresponding sensitivity threshold as effective new energy units; the short-circuit current sensitivity includes overcurrent coefficient sensitivity and fixed current multiple sensitivity.

3. The method for identifying the effective period of short-circuit current control measures for new energy units according to claim 2 is characterized in that: The overcurrent coefficient sensitivity is calculated using the following formula: ΔI j i,k =I j (k i +Δk,I i,qmax )-I j (k i ,I i,qmax ), Among them, ΔI j i,k It represents the sensitivity of the overcurrent coefficient of the i-th renewable energy unit to the overcurrent coefficient of the j-th busbar, I j (k i +Δk,I i,qmax ) represents the short-circuit current of the jth bus after the overcurrent coefficient is perturbed, I j (k i ,I i,qmax ) represents the short-circuit current of the jth bus before perturbation, k i represents the overcurrent coefficient of the i-th renewable energy unit, Δk represents the perturbation step of the overcurrent coefficient, I i,qmax Indicates the constant current multiple of the i-th renewable energy unit.

4. The method for identifying the effective period of short-circuit current control measures for new energy units according to claim 2 is characterized in that: The constant current multiple sensitivity is calculated using the following formula: ΔI j i,q =I j (k i ,I i,qmax +ΔI i,qmax )-I j (k i ,I i,qmax ), Among them, ΔI j i,q It represents the sensitivity of the fixed current multiple of the i-th renewable energy unit to the fixed current multiple of the j-th busbar, I j (k i ,I i,qmax +ΔI i,qmax ) represents the short-circuit current of the jth bus after the constant current multiple is perturbed, I j (k i ,I i,qmax ) represents the short-circuit current of the jth bus before perturbation, k i represents the overcurrent coefficient of the i-th renewable energy unit, I i,qmax Indicates the fixed current multiple of the i-th renewable energy unit, ΔI i,qmax Indicates the perturbation step size of the constant current multiple.

5. The method for identifying the effective period of short-circuit current control measures for new energy generator sets according to claim 1 is characterized in that: The restriction measure generation step includes: adjusting the overcurrent coefficient and the fixed current multiple of the effective new energy units respectively to obtain a plurality of corresponding adjustment schemes, combining the adjustment schemes of each new energy unit in the effective new energy unit set to obtain a plurality of candidate restriction measures corresponding to the effective new energy unit set; The overcurrent coefficient and the fixed current multiple of the effective new energy units are adjusted respectively to obtain corresponding multiple adjustment schemes, including: Determine the value range of overcurrent coefficient and fixed current multiple of effective new energy units; Keeping the overcurrent coefficient unchanged, taking values ​​one by one with a first perturbation step within the value range of the fixed current multiple, and obtaining multiple fixed current multiple parameter adjustment schemes; keeping the fixed current multiple unchanged, taking values ​​one by one with a second perturbation step within the value range of the overcurrent coefficient, and obtaining multiple overcurrent coefficient parameter adjustment schemes; The obtained constant current multiple parameter adjustment scheme and overcurrent coefficient parameter adjustment scheme are combined to obtain multiple adjustment schemes for effective new energy units.

6. The method for identifying effective time periods of short-circuit current control measures for new energy generator sets according to claim 1, characterized in that: The identification step includes: applying candidate restriction measures one by one to the first control mode in the unchecked control mode, according to whether the bus short-circuit current is higher than the safety standard and whether the transient voltage verification is passed.

7. The method for identifying the effective period of short-circuit current control measures for new energy units according to claim 6 is characterized in that: The parameter adjustment range of the effective new energy unit set and the effective restriction period are determined according to whether the bus short-circuit current is higher than the safety standard and whether the transient voltage check is passed, including: If there are candidate restriction measures to control the short-circuit current of the busbar not higher than the safety standard and the transient voltage check passes, the corresponding candidate restriction measures will be used as effective restriction measures, and the parameter adjustment range of the effective new energy unit set will be determined according to the parameter values ​​of all effective restriction measures. At the same time, the implementation period of the corresponding control mode will be used as the effective restriction period; If there is no candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard, or there is a candidate restriction measure to control the short-circuit current of the bus not higher than the safety standard but the transient voltage check fails, the parameter adjustment range of the current candidate restriction measure will be used, and the implementation period of the corresponding control method will be set as an invalid restriction period.

8. A system for identifying effective time periods of short-circuit current control measures for new energy units, characterized in that: include: Operation mode acquisition unit, short circuit identification unit, effective unit screening unit, restriction measure generation unit, effective restriction period identification unit, restriction measure regeneration unit and synthesis unit, among which: The operation mode acquisition unit is used to acquire multiple operation modes of the power grid in the future target period; The short-circuit identification unit is used to calibrate the short-circuit current of the bus in the power grid under various operation modes, screen out the operation mode in which the bus short-circuit current is higher than the safety standard during the target period, and use the screened operation mode as the mode to be controlled; The effective unit screening unit is used to screen the corresponding effective new energy units for the control mode to obtain an effective new energy unit set; The restriction measure generation unit is used to perform the restriction measure generation step on the effective new energy unit set to obtain multiple candidate restriction measures corresponding to the effective new energy unit set; The effective restriction period identification unit is used to perform the identification step to check the control mode to be controlled, determine the parameter adjustment range of the effective new energy unit set, and the effective restriction period; The restriction measure regeneration unit is used to execute the restriction measure generation step within the parameter adjustment range of the effective new energy unit set, obtain multiple candidate restriction measures corresponding to the effective new energy unit set again, and transfer to the effective restriction period identification unit to execute the identification step until all the control modes are identified; The synthesis unit is used to combine all the effective restriction time periods determined in the identification step to obtain all effective time periods of the short-circuit current control measures of the new energy units within the target time period and the corresponding candidate restriction measures.

9. An electronic device, characterized in that: It comprises a memory and a processor, wherein a computer program executable by the processor is stored in the memory, and when the computer program is executed by the processor, the method for identifying the effective period of short-circuit current control measures for new energy units described in any one of claims 1 to 7 is executed.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for identifying the effective period of short-circuit current control measures for new energy generator sets according to any one of claims 1 to 7 are implemented.

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