A load response simulation method and system based on a voltage control strategy

Abstract

The present invention relates to a load response simulation method and system based on a voltage control strategy, including: updating the actual power of the hybrid load in the power grid simulation system according to the bus voltage hung on the power grid simulation system; taking the power flow result of the power grid simulation system as the simulation result of the power grid simulation system; The technical solution proposed by the present invention embeds the hybrid load voltage response model under multiple working conditions into the continuous power grid simulation platform, enabling the load response simulation based on the voltage control strategy to form a closed loop with the dispatching control simulation and the power grid simulation, comprehensively and truly reflecting the impact of the load response under the voltage control strategy on the power grid operation; improving the stability of the simulation.

Description

Technical Field

[0001] The present invention relates to the field of power system automation, and particularly to a load response simulation method and system based on a voltage control strategy. Background Art

[0002] Based on the voltage static response characteristics of power loads, by formulating a voltage response strategy to control the regulation of load power, the load voltage response becomes an important active power regulation means for future power grids.

[0003] The active power voltage response characteristics under different operating conditions and different types of power loads are different. When the active power fluctuates caused by a power grid fault, it is usually necessary to adjust the tap of the on-load regulating transformer to regulate the bus voltage, so as to achieve the active power control of the load cluster connected to the bus to meet the power grid regulation requirements.

[0004] However, at present, the load response voltage control still lacks engineering application and on-site experimental conditions, and there is no relevant patent that can solve the corresponding problems. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the purpose of the present invention is to propose a load response simulation method based on a voltage control strategy. This method embeds the hybrid load voltage response model under multiple conditions into a continuous power grid simulation platform, enabling the load response simulation based on the voltage control strategy to be closed-loop with the dispatching control simulation and the power grid simulation, comprehensively and truly reflecting the impact of the load response under the voltage control strategy on the power grid operation, and improving the stability of the simulation.

[0006] The purpose of the present invention is achieved by the following technical solutions:

[0007] The present invention proposes a load response simulation method based on a voltage control strategy, which is improved in that the method includes:

[0008] Updating the actual power of the hybrid load in the power grid simulation system according to the bus voltage connected to the power grid simulation system;

[0009] Taking the power flow result of the power grid simulation system as the simulation result of the power grid simulation system.

[0010] Preferably, the updating the actual power of the hybrid load in the power grid simulation system according to the bus voltage connected to the power grid simulation system includes:

[0011] Determining the actual power P of the hybrid load in the power grid simulation system according to the following formula:

[0012] P = k1△P v + k2△P f

[0013] Where △Pv is the load voltage response component in the power grid simulation system; △P f is the load frequency response component in the power grid simulation system; k1 is the coefficient corresponding to the voltage response component in the power grid simulation system; k2 is the coefficient corresponding to the load frequency response component in the power grid simulation system.

[0014] Further, the load voltage response component △P in the power grid simulation system is determined by the following formula v :

[0015] △P v =P Id -P pu

[0016] In the formula, P Id is the active power of the hybrid load in the power grid simulation system; P pu is the rated power of the power grid in the power grid simulation system.

[0017] Further, the active power P of the hybrid load in the power grid simulation system is determined by the following formula Id :

[0018] If the bus voltage U in the power grid simulation system > 0.7U pu , then the active power P of the hybrid load in the power grid simulation system Id =C z U 2 +C i U + C p ; Otherwise, the active power P of the hybrid load in the power grid simulation system Id =C low U 2

[0019] Among them, U pu is the rated voltage of the power grid in the power grid simulation system; C z is the constant impedance load coefficient under normal pressure in the power grid simulation system; C i is the constant current load coefficient in the power grid simulation system; C p is the constant power load coefficient in the power grid simulation system; C low is the constant impedance load coefficient under voltage loss in the power grid simulation system.

[0020] Further, the constant impedance load coefficient C under normal pressure in the power grid simulation system is determined by the following formula z :

[0021]

[0022] In the formula, r z is the proportion of the constant impedance type load in the hybrid load in the power grid simulation system;

[0023] Determine the constant current load factor C in the power grid simulation system according to the following formula i :

[0024]

[0025] In the formula, r i is the proportion of the constant current type load in the mixed load in the power grid simulation system;

[0026] Determine the constant power load factor C in the power grid simulation system according to the following formula p :

[0027] C p = r p .p pu

[0028] In the formula, r p is the proportion of the constant power type load in the mixed load in the power grid simulation system;

[0029] Determine the constant impedance load factor C under the voltage loss state in the power grid simulation system according to the following formula low :

[0030]

[0031] In the formula, U is the bus voltage connected to the power grid simulation system.

[0032] The present invention provides a load response simulation system based on a voltage control strategy. The improvement lies in that the system includes:

[0033] An update module: used to update the actual power of the mixed load in the power grid simulation system according to the bus voltage connected to the power grid simulation system;

[0034] A simulation module: used to take the power flow result of the power grid simulation system as the simulation result of the power grid simulation system.

[0035] Preferably, the update module is used for:

[0036] Determine the actual power P of the mixed load in the power grid simulation system according to the following formula:

[0037] P = k1△P v + k2△P f

[0038] In the formula, △P v is the load voltage response component in the power grid simulation system; △P f is the load frequency response component in the power grid simulation system; k1 is the coefficient corresponding to the voltage response component in the power grid simulation system; k2 is the coefficient corresponding to the load frequency response component in the power grid simulation system.

[0039] Further, the load voltage response component △P in the power grid simulation system is determined by the following formula v :

[0040] △P v = P Id - P pu

[0041] In the formula, P Id is the active power of the hybrid load in the power grid simulation system; P pu is the rated power of the power grid in the power grid simulation system.

[0042] Further, the active power P of the hybrid load in the power grid simulation system is determined by the following formula Id :

[0043] If the bus voltage U in the power grid simulation system > 0.7U pu , then the active power P of the hybrid load in the power grid simulation system Id = C z U 2 + C i U + C p ; otherwise, the active power P of the hybrid load in the power grid simulation system Id = C low U 2

[0044] Among them, U pu is the rated voltage of the power grid in the power grid simulation system; C z is the constant impedance load coefficient under normal pressure in the power grid simulation system; C i is the constant current load coefficient in the power grid simulation system; C p is the constant power load coefficient in the power grid simulation system; C low is the constant impedance load coefficient under voltage loss in the power grid simulation system.

[0045] Further, the constant impedance load coefficient C under normal pressure in the power grid simulation system is determined by the following formula z :

[0046]

[0047] In the formula, r z is the proportion of the constant impedance type load in the hybrid load in the power grid simulation system;

[0048] The constant current load coefficient C in the power grid simulation system is determined by the following formula i :

[0049]

[0050] Wherein, r i is the proportion of constant - current type loads in the hybrid loads in the power grid simulation system;

[0051] The constant - power load coefficient C in the power grid simulation system is determined according to the following formula p :

[0052] C p = r p .p pu

[0053] Wherein, r p is the proportion of constant - power type loads in the hybrid loads in the power grid simulation system;

[0054] The constant - impedance load coefficient C under the voltage - loss state in the power grid simulation system is determined according to the following formula low :

[0055]

[0056] Wherein, U is the bus voltage connected to the power grid simulation system.

[0057] Compared with the closest prior art, the beneficial effects of the present invention are:

[0058] The technical solution provided by the present invention updates the actual power of the hybrid loads in the power grid simulation system according to the bus voltage connected to the power grid simulation system; uses the power flow result of the power grid simulation system as the simulation result of the power grid simulation system; this technical solution embeds the hybrid - load voltage response model under multiple working conditions into the continuous power grid simulation platform, enabling the load response simulation based on the voltage control strategy to form a closed - loop with the dispatching control simulation and the power grid simulation, comprehensively and truly reflecting the impact of the load response under the voltage control strategy on the power grid operation; meanwhile, the application of the hybrid - load voltage response model under multiple working conditions eliminates the drawbacks of unstable load characteristics of traditional voltage response models such as constant - impedance, constant - current, and constant - power load models, as well as the drawbacks of the gradually distorted constant - current and constant - impedance characteristics under the voltage - loss state; improving the stability of the simulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 is a flowchart of a load response simulation method based on a voltage control strategy;

[0060] Figure 2 is a structural diagram of a load response simulation system based on a voltage control strategy. DETAILED DESCRIPTION OF THE INVENTION

[0061] The following further details the specific embodiments of the present invention with reference to the accompanying drawings.

[0062] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0063] The simulation method provided by the present invention embeds a hybrid load voltage response model under multiple working conditions into a continuous power grid simulation platform, enabling the load response simulation based on the voltage control strategy to be closed-loop with the dispatching control simulation and the power grid simulation, comprehensively and truly reflecting the impact of the load response under the voltage control strategy on the power grid operation, improving the adaptability of the traditional load model, and improving the accuracy of the voltage response load simulation.

[0064] The present invention provides a load response simulation method based on a voltage control strategy, as Figure 1 shown, the method includes:

[0065] Step 101. Update the actual power of the hybrid load in the power grid simulation system according to the bus voltage in the power grid simulation system.

[0066] In the best embodiment of the present invention, the dispatching system issues a transformer voltage regulation command to adjust the tap position of the transformer; thereby changing the bus voltage in the power grid simulation system.

[0067] The adjusting the tap position of the transformer according to the transformer voltage regulation command of the dispatching system includes:

[0068] Step a: Judge whether the transformer voltage regulation command of the dispatching system is within the effective time limit range. If so, proceed to step 2; otherwise, end the operation.

[0069] Step b: Judge whether the target tap position of the transformer voltage regulation command of the dispatching system is within the adjustable range of the transformer taps; if so, adjust the tap position of the transformer to the target tap position of the transformer voltage regulation command of the dispatching system; otherwise, adjust the tap position of the transformer to the transformer adjustable tap position with the smallest difference from the target tap position of the transformer voltage regulation command of the dispatching system.

[0070] Step 102. Use the power flow result of the power grid simulation system as the simulation result of the power grid simulation system.

[0071] Specifically, step 101 includes:

[0072] Determine the actual power P of the hybrid load in the power grid simulation system according to the following formula:

[0073] P = k1△P v+k2△P f

[0074] wherein, △P v is the load voltage response component in the power grid simulation system; △P f is the load frequency response component in the power grid simulation system; k1 is the coefficient corresponding to the voltage response component in the power grid simulation system; k2 is the coefficient corresponding to the load frequency response component in the power grid simulation system.

[0075] Furthermore, the load voltage response component △P in the power grid simulation system is determined according to the following formula v :

[0076] △P v = P Id - P pu

[0077] wherein, P Id is the active power of the hybrid load in the power grid simulation system; P pu is the rated power of the power grid in the power grid simulation system.

[0078] Furthermore, the active power P of the hybrid load in the power grid simulation system is determined according to the following formula Id :

[0079] If the bus voltage U in the power grid simulation system > 0.7U pu , then the active power P of the hybrid load in the power grid simulation system Id = C z U 2 + C i U + C p ; otherwise, the active power P of the hybrid load in the power grid simulation system Id = C low U 2

[0080] wherein, U pu is the rated voltage of the power grid in the power grid simulation system; C z is the constant impedance load coefficient under normal pressure in the power grid simulation system; C i is the constant current load coefficient in the power grid simulation system; C p is the constant power load coefficient in the power grid simulation system; C low is the constant impedance load coefficient under voltage loss in the power grid simulation system.

[0081] In the best embodiment of the present invention, the constant current type and constant power type loads will lose their constant current and constant power characteristics under the voltage loss condition and degenerate into constant impedance characteristics.

[0082] In actual operation, the process of load degradation to a constant impedance characteristic occurs within a different and relatively narrow voltage range. To simplify the simulation, a load voltage response model under normal pressure conditions and a segmented load voltage response model under voltage loss conditions are adopted. The voltage segmentation boundary is 0.7 times the rated voltage.

[0083] Furthermore, the constant impedance load coefficient C under normal pressure conditions in the power grid simulation system is determined according to the following formula z :

[0084]

[0085] In the formula, r z is the proportion of the constant impedance type load in the mixed load in the power grid simulation system;

[0086] The constant current load coefficient C in the power grid simulation system is determined according to the following formula i :

[0087]

[0088] In the formula, r i is the proportion of the constant current type load in the mixed load in the power grid simulation system;

[0089] The constant power load coefficient C in the power grid simulation system is determined according to the following formula p :

[0090] C p = r p .p pu

[0091] In the formula, r p is the proportion of the constant power type load in the mixed load in the power grid simulation system;

[0092] The constant impedance load coefficient C under voltage loss conditions in the power grid simulation system is determined according to the following formula low :

[0093]

[0094] In the formula, U is the bus voltage connected to the power grid simulation system.

[0095] The present invention provides a load response simulation system based on a voltage control strategy. As Figure 2 shown, the system includes:

[0096] An update module: used to update the actual power of the mixed load in the power grid simulation system according to the bus voltage connected to the power grid simulation system;

[0097] A simulation module: used to take the power flow result of the power grid simulation system as the simulation result of the power grid simulation system.

[0098] Specifically, the update module is configured to:

[0099] Determine the actual power P of the hybrid load in the power grid simulation system according to the following formula:

[0100] P = k1ΔP v + k2ΔP f

[0101] In the formula, ΔP v is the load voltage response component in the power grid simulation system; ΔP f is the load frequency response component in the power grid simulation system; k1 is the coefficient corresponding to the voltage response component in the power grid simulation system; k2 is the coefficient corresponding to the load frequency response component in the power grid simulation system.

[0102] Furthermore, determine the load voltage response component ΔP in the power grid simulation system according to the following formula v :

[0103] ΔP v = P Id - P pu

[0104] In the formula, P Id is the active power of the hybrid load in the power grid simulation system; P pu is the rated power of the power grid in the power grid simulation system.

[0105] Furthermore, determine the active power P of the hybrid load in the power grid simulation system according to the following formula Id :

[0106] If the bus voltage U in the power grid simulation system > 0.7U pu , then the active power P of the hybrid load in the power grid simulation system Id = C z U 2 + C i U + C p ; otherwise, the active power P of the hybrid load in the power grid simulation system Id = C low U 2

[0107] Among them, U pu is the rated voltage of the power grid in the power grid simulation system; C z is the constant impedance load coefficient under normal pressure in the power grid simulation system; C i is the constant current load coefficient in the power grid simulation system; C p is the constant power load coefficient in the power grid simulation system; C low is the constant impedance load coefficient under voltage loss in the power grid simulation system.

[0108] Further, the constant impedance load factor C under normal pressure in the power grid simulation system is determined according to the following formula z :

[0109]

[0110] In the formula, r z is the proportion of the constant impedance type load in the mixed load in the power grid simulation system;

[0111] The constant current load factor C in the power grid simulation system is determined according to the following formula i :

[0112]

[0113] In the formula, r i is the proportion of the constant current type load in the mixed load in the power grid simulation system;

[0114] The constant power load factor C in the power grid simulation system is determined according to the following formula p :

[0115] C p = r p .p pu

[0116] In the formula, r p is the proportion of the constant power type load in the mixed load in the power grid simulation system;

[0117] The constant impedance load factor C under the voltage loss state in the power grid simulation system is determined according to the following formula low :

[0118]

[0119] In the formula, U is the bus voltage connected to the power grid simulation system.

[0120] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can adopt 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.

[0121] This application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows 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 the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0122] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0123] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or multiple blocks.

[0124] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications or equivalent replacements can still be made to the specific embodiments of the present invention, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A load response simulation method based on a voltage control strategy, characterized in that, The method includes: Updating the actual power of the hybrid load in the power grid simulation system according to the bus voltage connected to the power grid simulation system; Taking the power flow result of the power grid simulation system as the simulation result of the power grid simulation system; The updating the actual power of the hybrid load in the power grid simulation system according to the bus voltage connected to the power grid simulation system includes: Determining the actual power P of the hybrid load in the power grid simulation system according to the following formula: P = k1ΔP v + k2ΔP f where ΔP v is the load voltage response component in the power grid simulation system; ΔP f is the load frequency response component in the power grid simulation system; k1 is the coefficient corresponding to the voltage response component in the power grid simulation system; k2 is the coefficient corresponding to the load frequency response component in the power grid simulation system; Determine the load voltage response component ΔP in the power grid simulation system according to the following formula v :[[-END]] ΔP v = P Id - P pu where, P Id is the active power of the hybrid load in the power grid simulation system; P pu is the rated power of the power grid in the power grid simulation system; Determine the active power P of the hybrid load in the power grid simulation system according to the following formula Id :[[]]END]] If the bus voltage U in the power grid simulation system is greater than 0.7U pu , then the active power P of the hybrid load in the power grid simulation system Id = C z U 2 + C i U + C p ; Otherwise, the active power P of the hybrid load in the power grid simulation system Id = C low U 2 Among them, U pu is the rated voltage of the power grid in the power grid simulation system; C z is the constant impedance load coefficient under normal pressure in the power grid simulation system; C i is the constant current load coefficient in the power grid simulation system; C p is the constant power load coefficient in the power grid simulation system; C low is the constant impedance load coefficient under the voltage loss state in the power grid simulation system; Determine the constant impedance load factor C under normal pressure in the power grid simulation system according to the following formula z :[[]]END]] where r z is the proportion of constant impedance type loads in the hybrid load in the power grid simulation system; Determine the constant current load factor C in the power grid simulation system according to the following formula i :[[]]END]] where r i is the proportion of constant current type loads in the hybrid load in the power grid simulation system; Determine the constant power load factor C in the power grid simulation system according to the following formula p :[[]]END]] C p = r p .p pu where r p is the proportion of constant power type loads in the hybrid load in the power grid simulation system; Determine the constant impedance load factor C under the voltage loss state in the power grid simulation system according to the following formula low :[[]]END]] where U is the bus voltage connected to the power grid simulation system.

2. A load response simulation system based on a voltage control strategy, characterized in that, The system includes: An updating module: configured to update the actual power of the hybrid load in the power grid simulation system according to the bus voltage connected to the power grid simulation system; A simulation module: configured to take the power flow result of the power grid simulation system as the simulation result of the power grid simulation system; The updating module is configured to: Determine the actual power P of the hybrid load in the power grid simulation system according to the following formula: P = k1ΔP v + k2ΔP f where, ΔP v is the load voltage response component in the power grid simulation system; ΔP f is the load frequency response component in the power grid simulation system; k1 is the coefficient corresponding to the voltage response component in the power grid simulation system; k2 is the coefficient corresponding to the load frequency response component in the power grid simulation system; Determine the load voltage response component ΔP in the power grid simulation system according to the following formula v :[[-END]] ΔP v = P Id - P pu where P Id is the active power of the hybrid load in the power grid simulation system; P pu is the rated power of the power grid in the power grid simulation system; Determine the active power \(P\) of the hybrid load in the power grid simulation system according to the following formula Id : If the bus voltage U in the power grid simulation system is greater than 0.7U pu , then the active power P of the hybrid load in the power grid simulation system Id = C z U 2 + C i U + C p ; Otherwise, the active power P of the hybrid load in the power grid simulation system Id = C low U 2 Among them, U pu is the rated voltage of the power grid in the power grid simulation system; C z is the constant impedance load factor under normal pressure in the power grid simulation system; C i is the constant current load factor in the power grid simulation system; C p is the constant power load factor in the power grid simulation system; C low is the constant impedance load factor under the voltage loss state in the power grid simulation system; Determine the constant impedance load factor C under normal pressure in the power grid simulation system according to the following formula z :[[]]END]] where r z is the proportion of constant impedance type loads in the hybrid load in the power grid simulation system; Determine the constant current load factor C in the power grid simulation system according to the following formula i : where r i is the proportion of constant current type loads in the hybrid load in the power grid simulation system; Determine the constant power load factor C in the power grid simulation system according to the following formula p :[[]]END]] C p = r p .p pu where r p is the proportion of constant power type loads in the hybrid load in the power grid simulation system; Determine the constant impedance load factor C under the voltage loss state in the power grid simulation system according to the following formula low :[[]]END]] where U is the bus voltage connected to the power grid simulation system.

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