Cooperative voltage regulation method, device and equipment for reactive power regulation resources and storage medium

Abstract

The invention provides a reactive power regulation resource cooperative voltage regulation method, device and equipment and a storage medium, and the method comprises the steps: constructing a Zbus linearization power flow model based on single fixed point iteration for a transformer substation; based on the Zbus linearized power flow model, determining node voltage sensitivity of the transformer substation in different regulation modes and voltage regulation quantity of an on-load voltage regulation transformer; determining a voltage regulation range of the transformer substation based on the load and photovoltaic prediction data of the transformer substation under the same time scale; and determining a power adjustment range of the transformer substation in the voltage adjustment range in combination with the voltage reduction and energy saving coefficient. According to the method and the device, the safety of the network voltage can be fully considered, the tap of the on-load voltage regulation transformer in the power distribution network and the adjustable range of the corresponding voltage level are determined, and the problem that the voltage regulation effect of a transformer substation is poor in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the field of power control technology, and in particular to a method, device, equipment and storage medium for coordinated voltage regulation of reactive power regulation resources. Background Art

[0002] At present, with the construction of new power systems and the continuous advancement of energy transformation, the new energy industry is booming. Especially in the distribution network, the rapid growth of distributed new energy installed capacity has significantly increased the complexity of power grid operation and control. Due to the volatility and randomness of new energy, the active power balance of the system is often affected, and the widespread distribution of distributed new energy often leads to over-limit voltage at the end of the feeder. In order to meet these challenges, existing studies have suggested that by tapping the regulation potential of load-side resources, broadening the means of grid regulation, and improving the source-load interaction capability, the research focus is on how to aggregate and manage a large number of distributed resources. However, whether it is demand-side response or the establishment of load aggregators or virtual power plants, the control authority of these methods is not on the grid side, and they face problems of regulation compensation and initial investment. Therefore, the grid side urgently needs to explore active regulation resources that can be directly controlled.

[0003] The on-load tap changer (OLTC) in the substation is usually the most common grid-side direct control device in the distribution network, which adjusts the system voltage by adjusting the tap. Since the resistance of the distribution network is greater than the reactance, there is a strong coupling relationship between voltage and active power, so the active power can be controlled by adjusting the voltage. In order to ensure that the substation in the distribution network can stably participate in the regulation of active power, it is also necessary to clarify the overall voltage regulation capacity of the substation and fully consider the safety of the network voltage. However, there is currently a lack of systematic research on this issue. Therefore, how to determine the tap of the on-load tap changer in the distribution network and the adjustable range of its corresponding voltage level has become a key issue that needs to be solved urgently.

[0004] There is no effective solution to the problem of poor voltage regulation effect of substations in existing related technologies. Summary of the invention

[0005] The present invention provides a reactive regulation resource coordinated voltage regulation method, device, equipment and storage medium, which are used to solve the defect of poor voltage regulation effect of substation in the prior art.

[0006] In a first aspect, the present invention provides a reactive power regulation resource coordinated voltage regulation method, comprising:

[0007] For substations, a Zbus linearized power flow model based on single fixed point iteration is constructed;

[0008] Based on the Zbus linearized power flow model, determining the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer;

[0009] Determining a voltage regulation range of the substation based on load and photovoltaic forecast data of the substation at the same time scale;

[0010] The power adjustment range of the substation within the voltage regulation range is determined in combination with the voltage reduction energy saving coefficient.

[0011] According to a reactive regulation resource coordinated voltage regulation method provided by the present invention, a Zbus linearized power flow model based on a single fixed point iteration is constructed, including:

[0012] Based on the node voltage of the target node in the substation distribution network, an initial Zbus power flow model is constructed; the target node is an unbalanced node;

[0013] The initial Zbus power flow model is subjected to fixed point iteration processing to obtain a Zbus linearized power flow model based on a single fixed point iteration.

[0014] According to a reactive regulation resource coordinated voltage regulation method provided by the present invention, based on the Zbus linearized power flow model, determining the node voltage sensitivity of the substation under different regulation modes includes:

[0015] Obtaining the injected power of the substation distribution network;

[0016] The analytical relationship between the node voltage of the target node and the injected power is quantified based on the Zbus linearized power flow model to determine the node voltage sensitivity of the substation.

[0017] According to a reactive regulation resource coordinated voltage regulation method provided by the present invention, based on the Zbus linearized power flow model, determining the node voltage sensitivity of the substation under different regulation modes includes:

[0018] Obtaining a balancing node voltage in the substation distribution network;

[0019] The voltage of the balancing node is derived based on the Zbus linearized power flow model, and the node voltage sensitivity of the target node with respect to the balancing node is determined in combination with the node voltage of the target node.

[0020] According to a reactive regulation resource coordinated voltage regulation method provided by the present invention, determining the voltage regulation amount of an on-load voltage regulating transformer includes:

[0021] Obtaining operation constraints of an on-load tap-changing transformer in the substation distribution network;

[0022] A voltage regulation amount of the on-load tap-changing transformer is determined based on an operation constraint of the on-load tap-changing transformer.

[0023] According to a reactive regulation resource coordinated voltage regulation method provided by the present invention, based on the load and photovoltaic prediction data of the substation at the same time scale, the voltage regulation range of the substation is determined, including:

[0024] Determining the load active power at the downstream point of the substation;

[0025] performing data processing on the load and photovoltaic prediction data of the substation according to cubic spline interpolation;

[0026] The voltage regulation range of the substation is determined based on the load active power at the downstream grid point of the substation and the voltage regulation amount of the on-load tap-changing transformer of the substation.

[0027] According to a reactive regulation resource coordinated voltage regulation method provided by the present invention, the power adjustment range of the substation within the voltage regulation range is determined in combination with the voltage reduction energy saving coefficient, including:

[0028] Determining the voltage reduction energy saving coefficient based on the load active power change rate of the substation and the voltage change rate of the target node;

[0029] Based on the voltage regulation range of the substation and the voltage reduction energy saving coefficient, a power adjustment range of the substation within the voltage regulation range is determined.

[0030] In a second aspect, the present invention further provides a reactive power regulation resource coordinated voltage regulation device, comprising:

[0031] A construction module is used to construct a Zbus linearized power flow model based on a single fixed point iteration for a substation;

[0032] An operation module is used to determine the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer based on the Zbus linearized power flow model;

[0033] A processing module, used to determine the voltage regulation range of the substation based on the load and photovoltaic prediction data of the substation at the same time scale;

[0034] The determination module is used to determine the power adjustment range of the substation within the voltage regulation range in combination with the voltage reduction energy saving coefficient.

[0035] In a third aspect, the present invention further provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for coordinated voltage regulation of reactive power regulation resources as described in the first aspect above is implemented.

[0036] In a fourth aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the reactive power regulation resource coordinated voltage regulation method as described in the first aspect above.

[0037] In a fifth aspect, the present invention further provides a computer program product, comprising a computer program, which, when executed by a processor, implements the reactive power regulation resource coordinated voltage regulation method as described in the first aspect above.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] The reactive regulation resource coordinated voltage regulation method provided by the present invention determines the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer by constructing a Zbus linearized power flow model based on a single fixed point iteration. Then, the short-term source-load forecast data is comprehensively considered, the time scales of the load and photovoltaic forecast data are aligned, and then the voltage regulation range and power adjustment range of the substation are evaluated. Through the above process, the overall voltage regulation capacity of the substation can be clarified, the safety of the network voltage can be fully considered, the tap of the on-load tap-changing transformer in the distribution network and the adjustable range of the corresponding voltage level can be determined, and the problem of poor voltage regulation effect of the substation existing in the existing related technologies can be solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 It is a flow chart of the reactive power regulation resource coordinated voltage regulation method provided by the present invention;

[0042] Figure 2 is a schematic diagram of a fixed point iteration process in an embodiment of the present invention;

[0043] Figure 3 is a schematic diagram comparing different linearization methods in an embodiment of the present invention;

[0044] Figure 4 It is a structural block diagram of the reactive power regulation resource coordinated voltage regulation device provided by the present invention;

[0045] Figure 5 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are 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 are within the scope of protection of the present invention.

[0047] The present invention provides a reactive power regulation resource coordinated voltage regulation method. Figure 1 is a flow chart of the reactive power regulation resource coordinated voltage regulation method provided by the present invention, such as Figure 1 As shown, the method comprises the following steps:

[0048] Step S101, constructing a Zbus linearized power flow model based on a single fixed point iteration for a substation;

[0049] Step S102, based on the Zbus linearized power flow model, determining the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer;

[0050] Step S103, determining the voltage regulation range of the substation based on the load and photovoltaic prediction data of the substation at the same time scale;

[0051] Step S104, determining the power adjustment range of the substation within the voltage regulation range in combination with the voltage reduction energy saving coefficient.

[0052] In this method, for the substation that needs to determine the regulation scheme, first, a Zbus linearized power flow model based on a single fixed point iteration is constructed. The Zbus power flow model is a method used in the power system to analyze the distribution of parameters such as voltage, phase angle and power at each node in the power system to determine the steady-state working state of the power system. The equation of the Zbus power flow model has obvious iterative function characteristics, so it can be solved by fixed point iteration, but the fixed point iteration requires multiple calculations and the algorithm complexity is high. In order to improve the solution efficiency, this method adopts a linear approximation method based on a single fixed point iteration (FFPI) to construct a linearized power flow model of the Zbus nonlinear model about the reference power flow point through a single-step iteration. The model can be used to calculate the partial derivative of the voltage of each target node relative to the injected power, thereby obtaining an expression for the point-to-point voltage sensitivity. In this way, the analytical relationship between the target node voltage and the injected power can be quantified, greatly reducing the computational complexity. Then, the short-term source-load forecast data is comprehensively considered, the time scales of the load and photovoltaic forecast data are aligned, and the voltage regulation range and power adjustment range of the substation are evaluated. Through the above process, the overall voltage regulation capacity of the substation can be clarified, the safety of the network voltage can be fully considered, the tap of the on-load tap-changing transformer in the distribution network and the adjustable range of the corresponding voltage level can be determined, and the problem of poor voltage regulation effect of the substation existing in the existing related technologies can be solved.

[0053] In some of the embodiments, step S101, constructing a Zbus linearized power flow model based on a single fixed point iteration, includes: constructing an initial Zbus power flow model based on the node voltage of a target node in a substation distribution network; the target node is an unbalanced node; and performing fixed point iteration processing on the initial Zbus power flow model to obtain a Zbus linearized power flow model based on a single fixed point iteration.

[0054] The goal of the Zbus power flow model is to solve the voltage and phase angle of each node in the power system so that each component in the system (generator, transformer, line, load, etc.) satisfies constraints such as power balance and power flow balance. In a typical distribution network system, it is generally believed that the voltage of the balancing node (generally the root node) remains unchanged, and other nodes can be regarded as PQ nodes. According to the superposition principle, the voltage Ui of node i is composed of two parts: the voltage Ui1 generated by the root node (regarded as a voltage source) at node i and the voltage Ui2 generated by the remaining PQ nodes (regarded as current sources) at node i. For a system with 1 balancing node and N PQ nodes, the power flow equation is as follows:

[0055]

[0056] I=YU

[0057] Among them, S is the target node injection power, U is the voltage phasor of each target node, and I is the injection current of each target node. The matrices are divided according to the balance node and PQ node, and the following form can be obtained:

[0058]

[0059] The matrix is ​​divided into blocks based on whether it is a balanced node, I 0 , S 0 and V 0 are the balanced node injection current, node injection power and node voltage respectively; I, S and V are the injection current vector, node injection power vector and node voltage vector of PQ node respectively, Y is the node admittance matrix of the system, Y 00 is the self-admittance of the equilibrium node, Y 0L , Y L0 is the mutual admittance matrix between the balancing node and the PQ node, Y LL is the admittance matrix of all PQ nodes. 00 is a 1×1 matrix, Y 0L is a 1×n matrix, Y L0 is an n×1 matrix, Y LL is an n×n matrix.

[0060] According to the above Zbus power flow equation, the PQ node injection power equation and the injection current equation are combined, and the node injection current vector I is eliminated, and then the implicit expression of the PQ node voltage is obtained, which includes the current source part affected by the PQ node injection power and the voltage source part affected by the equilibrium node voltage. The implicit expression is as follows:

[0061]

[0062] Among them, the first term is the voltage generated by each PQ node (current source), and the second term is the voltage generated by the root node (voltage source), which is approximately a constant and is set to W. Therefore, the initial Zbus power flow model is:

[0063]

[0064] The Zbus power flow model has clear physical concepts and uses the Y matrix with sparse characteristics and the equivalent current source injection form to reduce computing memory and improve computing efficiency.

[0065] For any nonlinear function y = f(x), when solving for its zero point x 0 When f(x 0 )=0, it can be written in another equivalent form x 0 =Ψ(x 0 ), called x 0 is the function Ψ(x0 ), the actual fixed point is the intersection of the original function and the function y = x. The process of calculating the zero point of the nonlinear function by calculating the fixed point is called fixed point iteration. The iteration process is as follows Figure 2 As shown, Figure 2 : is a schematic diagram of the fixed point iteration process in an embodiment of the present invention, and the iteration formula is as follows:

[0066]

[0067] From the initial Zbus power flow model expression, it can be obtained that the Zbus power flow equation has obvious iterative function characteristics. The left side of the equation is the voltage U of each PQ node, and the right side is a function of V. Therefore, it can be solved by fixed point iteration. However, fixed point iteration requires multiple calculations and the algorithm complexity is high. Therefore, a linear approximation method based on a single fixed point iteration is used here to construct a linearized power flow model of the Zbus nonlinear model about the reference power flow point through single-step iteration. At this time, the latest operating point U of the system is selected 0 'As a reference flow point, when the system flow changes, the node power is updated and the node voltage V is obtained according to the following formula:

[0068]

[0069] in, Once the line topology, parameters and reference flow points are determined, A and W can be calculated offline. The above formula constructs a linear relationship between the node voltage V and the injected power S of each node in the system, which significantly reduces the complexity of the solution process.

[0070] The essence of this single fixed point iteration method is the linear interpolation between two power flow points (0, W) and (S0', U0') of the system. This is fundamentally different from the standardized linearization method of cutting the plane at a feasible solution, such as Taylor's first-order expansion, which allows the linear approximation method based on single fixed point iteration to maintain high accuracy in a larger range. The comparison of different linearization methods is shown in Figure 2. Figure 3 As shown, Figure 3 Schematic diagram of comparison of different linearization methods in the embodiments of the present invention.

[0071] In some of the embodiments, step S102, based on the Zbus linearized power flow model, determines the node voltage sensitivity of the substation under different regulation modes, including: obtaining the injected power of the substation distribution network; quantifying the analytical relationship between the node voltage and the injected power of the target node based on the Zbus linearized power flow model, and determining the node voltage sensitivity of the substation.

[0072] Voltage sensitivity refers to the degree of response of node voltage to power changes in the power system (VTL process). Specifically, it measures the degree of influence of power changes in the power system on node voltage. Power voltage sensitivity can be obtained by calculating the derivative of node voltage with respect to factors such as load power changes, generator output power changes, or line parameter changes. Traditionally, voltage sensitivity is obtained by inverting the Jacobian matrix, but this method is computationally intensive and difficult to use for real-time control, and it is also impossible to obtain the voltage sensitivity of the balancing node. Therefore, based on the Zbus power flow model in the previous section, the partial derivative of each node voltage with respect to the injected power can be calculated to obtain the expression of voltage sensitivity as follows, which can quantify the analytical relationship between node voltage and injected power, greatly reducing the computational complexity:

[0073]

[0074] Among them, V is the voltage matrix of each PQ node, P and Q are the active and reactive power matrices of each PQ node respectively. Running point for the latest trend.

[0075] In some of the embodiments, step S102, based on the Zbus linearized power flow model, determines the node voltage sensitivity of the substation under different regulation modes, including: obtaining the balancing node voltage in the substation distribution network; derivatizing the balancing node voltage based on the Zbus linearized power flow model, and determining the node voltage sensitivity of the target node with respect to the balancing node in combination with the node voltage of the target node.

[0076] In addition to the fact that the power injected into each PQ node will cause the voltage of each node to change, the voltage change of the root node will also affect the voltage of each node. In the linearized power flow model based on ZBus, the node voltage of each PQ node is also linearly related to the voltage vector of the balance node. Therefore, the balance node voltage V0 can also be derived according to the linearized power flow equation, thereby realizing the rapid calculation of the sensitivity of the PQ node to the balance node voltage. According to the power flow model, the voltage sensitivity of each PQ node with respect to the root node is solved as follows:

[0077]

[0078] The above formula establishes a linear relationship between the voltage of each PQ node and the root node voltage. Using this relationship, the impact of the balance node voltage change on the voltage change of each PQ node can be quantitatively determined.

[0079] In the distribution network, the voltage of the PQ node is mainly affected by two aspects. First, the gear adjustment of the substation on-load tap changer (OLTC) will cause the change of the balancing node voltage, which will lead to the change of the voltage of each PQ node. Second, the change of load power will also cause the change of node voltage. Since the distribution network line has a high R / X ratio, there is a strong coupling relationship between voltage and active power and reactive power.

[0080] In summary, the voltage of each PQ node is closely related to the voltage of the balancing node and the active and reactive power of each node. By analyzing the Zbus linearized power flow model based on fixed point iteration, the voltage sensitivity can be obtained, and then the linear relationship between these variables can be established, which provides theoretical support for the boundary calculation of substation voltage regulation.

[0081] In some embodiments, step S102, determining the voltage regulation amount of the on-load tap-changing transformer, includes: obtaining the operating constraints of the on-load tap-changing transformer in the substation distribution network; and determining the voltage regulation amount of the on-load tap-changing transformer based on the operating constraints of the on-load tap-changing transformer.

[0082] The on-load tap-changing transformer is a typical traditional discrete voltage regulating device, which needs to meet the constraints of its tap adjustment range. Through the operation constraints of the on-load tap-changing transformer, its voltage regulation can be calculated. The corresponding constraints are as follows:

[0083] ΔV OLTC =ΔkΔV tap

[0084] k min ≤k 2 ≤k 0,t ≤k 1 ≤k max

[0085] Where k represents the tap position after OLTC adjustment in period t, and is taken as k in the two scenarios. 1 and k 2 ; ΔV OLTC k is the voltage regulation value of the on-load tap-changing transformer; min and k max are the minimum and maximum positions of the on-load tap changer, ΔV tap Represents the voltage adjustment step of the on-load tap changer, that is, the voltage change corresponding to a unit tap position change.

[0086] In some of the embodiments, step S103, based on the load and photovoltaic prediction data of the substation at the same time scale, determines the voltage regulation range of the substation, including: determining the active power of the load at the downstream point of the substation; performing data processing on the load and photovoltaic prediction data of the substation according to cubic spline interpolation; determining the voltage regulation range of the substation based on the active power of the load at the downstream point of the substation and the voltage regulation amount of the on-load tap-changing transformer of the substation.

[0087] The output of distributed photovoltaic power is affected by the external environment and has the characteristics of randomness and volatility. If there are no measures to smooth the fluctuation of photovoltaic power in the distribution network, the fluctuation of photovoltaic power will be directly reflected in the coupling point between the distribution network and the main network, that is, the downstream network point. Therefore, effectively smoothing the violent fluctuation of the power at the downstream network point is a key means to improve the local consumption of photovoltaic power, ensure the utilization rate of equipment, and reduce the impact of the distribution network on the main network. The power calculation of the downstream network point is shown in the following formula:

[0088]

[0089] Among them, P t pcc is the active power at the grid point at time t; is the active power of the fth feeder load; P t loss N is the internal network loss of the distribution network; F is the total number of feeders in the distribution network; N B is the total number of nodes in the distribution network; is the distributed photovoltaic active power of the mth node in the distribution network. To unify the standard with the load power direction, when the photovoltaic outputs power Equivalent to "negative power load".

[0090] The pre-dispatch stage depends on the short-term forecast value of load and photovoltaic output. Under the premise of ensuring accuracy, the current load and photovoltaic short-term forecast cycle is 15 minutes, so this embodiment selects the pre-dispatch cycle as 15 minutes. In real-time control, feedback control is performed through the actual data taken by the power grid measurement equipment, so the real-time control step size Tc is related to the sampling frequency of the measurement device in the system.

[0091] From the above content, it can be seen that the power of the downstream grid is obtained by summing the load power, photovoltaic power and distribution network loss. The distribution network loss is relatively fixed and accounts for a small proportion of the power of the downstream grid. It can be considered as a constant value under a certain accuracy. The load power has a strong regularity. At this stage, the accuracy of load prediction can reach a time scale of 1 minute, but due to the strong volatility and randomness of photovoltaic output, the current mature prediction level can only reach a time scale of 15 minutes. Therefore, in order to ensure the accuracy of pre-dispatch, the pre-dispatch period Tp is selected as 15 minutes. However, since the prediction step size of photovoltaic and load is not uniform, in order to obtain the fluctuation rate of the downstream grid power every minute within the pre-dispatch period, it is necessary to align the time scales of photovoltaic and load prediction data.

[0092] Cubic spline interpolation is the main processing method for photovoltaic data. First, cubic spline interpolation (Spline) is used to process the 15-minute photovoltaic prediction data to convert it into 1-minute time scale data, and then the power prediction value of the grid point is calculated. The calculation process is shown in the formula:

[0093]

[0094] Wherein, Sp is the cubic spline interpolation function; and They are the 15-minute and 1-minute predicted values ​​of photovoltaic output respectively; and They are the 1-minute predicted value of load active power, the 1-minute predicted value of downstream active power and the distribution network loss.

[0095] With the widespread application of renewable energy, especially photovoltaic power generation, in distribution networks, the voltage regulation mechanism of substations has become more complicated. The volatility of photovoltaic power generation and the dynamic changes of load active power have posed new challenges to the voltage stability of the power grid. In this context, it is particularly important to evaluate the voltage regulation range of substations that combine load active power with photovoltaic power generation.

[0096] The coupling relationship between load active power and photovoltaic power generation significantly affects the voltage regulation process in the power grid. Photovoltaic systems are usually equipped with inverters to provide active power support. In the power system, the voltage regulation capability of the substation is achieved through the on-load tap-changing transformer (OLTC). The OLTC can adjust the output voltage by adjusting its taps, thereby controlling the voltage level of the distribution network. Since the resistance in the distribution network is much larger than the reactance, the coupling between voltage and active power is more obvious, so the substation can indirectly achieve active power regulation by adjusting the voltage.

[0097] In the distribution network, since the resistance is much greater than the reactance, there is a strong coupling relationship between the voltage and active power of the system. Therefore, by adjusting the OLTC, not only can the bus voltage be adjusted, but the active power can also be indirectly controlled. In order to ensure the safe and stable operation of the power grid, it is necessary to calculate the upper and lower limits of the substation voltage regulation, that is, the voltage regulation range. In practical applications, to evaluate the voltage regulation range of the substation, it is usually necessary to calculate the voltage sensitivity of each node for evaluation. The node voltage is affected by the changes in load power and photovoltaic power generation power. The dynamics of load active power and photovoltaic output have put forward new requirements for maximizing the voltage regulation range.

[0098] In order to quantitatively evaluate the voltage regulation capability of a substation, the following formula can be used:

[0099]

[0100] Where, ΔV range Indicates the voltage regulation range of the substation, ΔV OLTC Indicates the voltage regulation of the on-load tap-changing transformer. Indicates the sensitivity of voltage to active power, ΔP PV Indicates the change in active power of photovoltaic power generation, ΔP load Indicates the change in load active power.

[0101] Based on the above embodiment, step S104, combining the Conservation Voltage Reduction (CVR) coefficient to determine the power adjustment range of the substation within the voltage regulation range, includes: determining the conservation voltage reduction coefficient based on the load active power change rate of the substation and the voltage change rate of the target node; determining the power adjustment range of the substation within the voltage regulation range based on the voltage regulation range of the substation and the conservation voltage reduction coefficient.

[0102] In the voltage regulation control of substations, the CVR coefficient is a key parameter used to measure the impact of voltage changes on load power demand. The CVR coefficient is defined as the ratio of the load active power change rate to the voltage change rate, usually expressed as:

[0103]

[0104] Among them, ΔV represents the voltage change, ΔP load Indicates the change in load active power, and V indicates the rated voltage of the system. The CVR coefficient can be used to quantify the impact of voltage regulation on load power. After the voltage regulation range of the substation is known, the power adjustment range of the substation within the voltage regulation range can be calculated in combination with the CVR coefficient. range When the power adjustment range of the substation ΔP is obtained according to the CVR coefficient, the following formula is used: range :

[0105] ΔP range =CVR·ΔV range ·P base

[0106] Among them, ΔP range Indicates the adjustable power range of the substation, CVR indicates the voltage reduction energy saving coefficient, which is used to characterize the impact of voltage changes on power, ΔV range Indicates the voltage regulation range of the substation, P base Expressed as the basic active power of the system, usually the rated power.

[0107] The present invention also provides a reactive power regulation resource collaborative voltage regulation device. The reactive power regulation resource collaborative voltage regulation device provided by the present invention is described below. The reactive power regulation resource collaborative voltage regulation device described below and the reactive power regulation resource collaborative voltage regulation method described above can be referenced to each other. Figure 4 is a structural block diagram of the reactive power regulation resource coordinated voltage regulation device provided by the present invention, such as Figure 4 As shown, the device comprises:

[0108] A construction module 401 is used to construct a Zbus linearized power flow model based on a single fixed point iteration for a substation;

[0109] An operation module 402 is used to determine the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer based on the Zbus linearized power flow model;

[0110] The processing module 403 is used to determine the voltage regulation range of the substation based on the load and photovoltaic prediction data of the substation at the same time scale;

[0111] The determination module 404 is used to determine the power adjustment range of the substation within the voltage regulation range in combination with the voltage reduction energy saving coefficient.

[0112] When the device is in use, for a substation that needs to determine a regulation scheme, first, the construction module 401 constructs a Zbus linearized power flow model based on a single fixed point iteration. The Zbus power flow model is a method used in a power system to analyze the distribution of parameters such as voltage, phase angle and power at each node in the power system to determine the steady-state working state of the power system. The equation of the Zbus power flow model has obvious iterative function characteristics, so it can be solved by fixed point iteration, but the fixed point iteration requires multiple calculations and the algorithm complexity is high. In order to improve the solution efficiency, this method adopts a linear approximation method based on a single fixed point iteration, and constructs a linearized power flow model of the Zbus nonlinear model about the reference power flow point through a single-step iteration. Then, the operation module 402 uses the model to calculate the partial derivative of each target node voltage relative to the injected power, thereby obtaining an expression of the point voltage sensitivity. This can quantify the analytical relationship between the target node voltage and the injected power, greatly reducing the computational complexity. Then, the processing module 403 and the determination module 404 comprehensively consider the short-term source-load prediction data, align the time scales of the load and photovoltaic prediction data, and then evaluate the voltage regulation range and power adjustment range of the substation. Through the above process, the overall voltage regulation capacity of the substation can be clarified, the safety of the network voltage can be fully considered, the tap of the on-load tap-changing transformer in the distribution network and the adjustable range of the corresponding voltage level can be determined, and the problem of poor voltage regulation effect of the substation existing in the existing related technologies can be solved.

[0113] Figure 5 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 5 As shown, the electronic device may include: a processor 501, a communication interface 502, a memory 503 and a communication bus 504, wherein the processor 501, the communication interface 502, and the memory 503 communicate with each other through the communication bus 504. The processor 501 may call the logic instructions in the memory 503 to execute the reactive regulation resource coordinated voltage regulation method, which includes:

[0114] For substations, a Zbus linearized power flow model based on single fixed point iteration is constructed;

[0115] Based on the Zbus linearized power flow model, the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer are determined;

[0116] Determine the voltage regulation range of the substation based on the load and photovoltaic forecast data of the substation on the same time scale;

[0117] The power adjustment range of the substation within the voltage regulation range is determined in combination with the voltage reduction energy saving coefficient.

[0118] In addition, the logic instructions in the above-mentioned memory 503 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0119] On the other hand, the present invention further provides a computer program product, the computer program product includes a computer program, the computer program can be stored in a non-transitory computer-readable storage medium, when the computer program is executed by a processor, the computer can execute the reactive power regulation resource coordinated voltage regulation method provided by the above methods, the method includes:

[0120] For substations, a Zbus linearized power flow model based on single fixed point iteration is constructed;

[0121] Based on the Zbus linearized power flow model, the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer are determined;

[0122] Determine the voltage regulation range of the substation based on the load and photovoltaic forecast data of the substation on the same time scale;

[0123] The power adjustment range of the substation within the voltage regulation range is determined in combination with the voltage reduction energy saving coefficient.

[0124] In another aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when the computer program is executed by a processor to execute the reactive power regulation resource coordinated voltage regulation method provided by the above methods, the method comprising:

[0125] For substations, a Zbus linearized power flow model based on single fixed point iteration is constructed;

[0126] Based on the Zbus linearized power flow model, the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer are determined;

[0127] Determine the voltage regulation range of the substation based on the load and photovoltaic forecast data of the substation on the same time scale;

[0128] The power adjustment range of the substation within the voltage regulation range is determined in combination with the voltage reduction energy saving coefficient.

[0129] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, i.e., they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0130] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0131] 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 aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for coordinated voltage regulation using reactive power regulation resources, characterized in that: include: For substations, a Zbus linearized power flow model based on single fixed point iteration is constructed; Based on the Zbus linearized power flow model, determining the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer; Determining a voltage regulation range of the substation based on load and photovoltaic forecast data of the substation at the same time scale; The power adjustment range of the substation within the voltage regulation range is determined in combination with the voltage reduction energy saving coefficient.

2. The method for coordinated voltage regulation using reactive power regulation resources according to claim 1, characterized in that: Construct a Zbus linearized power flow model based on a single fixed point iteration, including: Based on the node voltage of the target node in the substation distribution network, an initial Zbus power flow model is constructed; the target node is an unbalanced node; The initial Zbus power flow model is subjected to fixed point iteration processing to obtain a Zbus linearized power flow model based on a single fixed point iteration.

3. The method for coordinated voltage regulation using reactive power regulation resources according to claim 1, characterized in that: Based on the Zbus linearized power flow model, determining the node voltage sensitivity of the substation under different regulation modes includes: Obtaining the injected power of the substation distribution network; The analytical relationship between the node voltage of the target node and the injected power is quantified based on the Zbus linearized power flow model to determine the node voltage sensitivity of the substation.

4. The method for coordinated voltage regulation using reactive power regulation resources according to claim 1, characterized in that: Based on the Zbus linearized power flow model, determining the node voltage sensitivity of the substation under different regulation modes includes: Obtaining a balancing node voltage in the substation distribution network; The voltage of the balancing node is derived based on the Zbus linearized power flow model, and the node voltage sensitivity of the target node with respect to the balancing node is determined in combination with the node voltage of the target node.

5. The method for coordinated voltage regulation using reactive power regulation resources according to claim 1, characterized in that: Determine the voltage regulation of the on-load tap-changing transformer, including: Obtaining operation constraints of an on-load tap-changing transformer in the substation distribution network; A voltage regulation amount of the on-load tap-changing transformer is determined based on an operation constraint of the on-load tap-changing transformer.

6. The method for coordinated voltage regulation using reactive power regulation resources according to claim 1, characterized in that: Determining the voltage regulation range of the substation based on the load and photovoltaic prediction data of the substation at the same time scale includes: Determining the load active power at the downstream point of the substation; performing data processing on the load and photovoltaic prediction data of the substation according to cubic spline interpolation; The voltage regulation range of the substation is determined based on the load active power at the downstream grid point of the substation and the voltage regulation amount of the on-load tap-changing transformer of the substation.

7. The method for coordinated voltage regulation using reactive power regulation resources according to claim 1, characterized in that: Determining the power adjustment range of the substation within the voltage regulation range in combination with the voltage reduction energy saving coefficient includes: Determining the voltage reduction energy saving coefficient based on the load active power change rate of the substation and the voltage change rate of the target node; Based on the voltage regulation range of the substation and the voltage reduction energy saving coefficient, a power adjustment range of the substation within the voltage regulation range is determined.

8. A reactive power regulation resource coordinated voltage regulation device, characterized in that: include: A construction module is used to construct a Zbus linearized power flow model based on a single fixed point iteration for a substation; An operation module is used to determine the node voltage sensitivity of the substation under different regulation modes and the voltage regulation amount of the on-load tap-changing transformer based on the Zbus linearized power flow model; A processing module, used to determine the voltage regulation range of the substation based on the load and photovoltaic prediction data of the substation at the same time scale; The determination module is used to determine the power adjustment range of the substation within the voltage regulation range in combination with the voltage reduction energy saving coefficient.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the reactive power regulation resource coordinated voltage regulation method as described in any one of claims 1 to 7 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the reactive power regulation resource coordinated voltage regulation method as described in any one of claims 1 to 7 is implemented.

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