Synchronous phase modifier capacity optimization method and device, storage medium and electronic equipment

Abstract

The invention discloses a synchronous phase modifier capacity optimization method and device, a storage medium and electronic equipment. The method comprises the following steps: acquiring operation control parameters of a near region of an extra-high-voltage direct-current sending-end power grid; based on the operation control parameters, a reactive power demand model of the converter station is constructed, and the reactive power demand model is used for indicating the reactive power demand change condition of the converter station when the extra-high voltage direct current sending end power grid is in the direct current locking state; based on the reactive power demand model, constructing a capacity coordination optimization model of the synchronous phase modifier in the extra-high-voltage direct-current sending-end power grid; and obtaining a capacity optimization result of the synchronous phase modifier based on the capacity coordination optimization model. According to the method and the device, the technical problem of poor reactive compensation effect caused by incomplete consideration factors and poor capacity optimization effect of a synchronous phase modifier capacity optimization method in related technologies is solved.

Description

Technical Field

[0001] The present invention relates to the field of smart grids, and in particular to a synchronous phase condenser capacity optimization method, device, storage medium and electronic equipment. Background Art

[0002] The steady-state voltage regulation mode of the DC converter station will have a direct impact on the dynamic reactive power support capacity of the system. By optimizing the configuration of the capacity of the phase condenser and the static reactive compensation equipment, the reactive compensation scheme is coordinated and customized, the phase condenser and the static capacitor are replaced with reactive power, the investment in the static reactive compensation equipment is reduced, and the steady-state reactive power output of the phase condenser is increased. This can reduce the impact of the output characteristics of the static compensation equipment on the transient voltage after the DC fault. The coordinated control method of synchronous phase condensers and static capacitors in the related technology is mostly focused on the voltage coordination control and multi-objective reactive voltage control in the transition process after the transient process. The research still focuses on the reactive power support of synchronous phase condensers and static capacitors to the voltage during the fault period. The factors considered are not comprehensive, and the capacity allocation is counter-targeted and the allocation effect is poor, which leads to poor reactive power compensation effect.

[0003] To address the above-mentioned problems, no effective solution has been proposed yet. Summary of the invention

[0004] The embodiments of the present invention provide a synchronous phase condenser capacity optimization method, device, storage medium and electronic device to at least solve the technical problem that the synchronous phase condenser capacity optimization method in the related art does not take comprehensive factors into consideration, the capacity optimization effect is poor, and the reactive power compensation effect is poor.

[0005] According to one aspect of an embodiment of the present invention, a method for optimizing the capacity of a synchronous condenser is provided, comprising: obtaining operation control parameters of a near zone of an ultra-high voltage direct current (UHVDC) sending-end power grid, wherein the near zone is used to indicate a zone in the ultra-high voltage direct current (UHVDC) sending-end power grid whose electrical distance to a converter station is less than a predetermined distance; constructing a reactive power demand model of the converter station based on the operation control parameters, wherein the reactive power demand model is used to indicate a change in reactive power demand of the converter station when the ultra-high voltage direct current (UHVDC) sending-end power grid is in a DC blocking state; constructing a capacity coordination optimization model of a synchronous condenser in the ultra-high voltage direct current (UHVDC) sending-end power grid based on the reactive power demand model, wherein the capacity coordination optimization model is used to coordinate the reactive power output of the synchronous condenser in a steady-state or transient operation scenario under the influence of a preset objective function and constraint conditions; obtaining a capacity optimization result of the synchronous condenser based on the capacity coordination optimization model, wherein the capacity optimization result is used to at least indicate the number of static reactive compensation devices put into operation in the ultra-high voltage direct current (UHVDC) sending-end power grid under transient operation conditions, and the reactive power output by the synchronous condenser.

[0006] According to another aspect of an embodiment of the present invention, a synchronous phase condenser capacity optimization device is also provided, including: a parameter acquisition module, used to obtain operation control parameters of a near zone of an ultra-high voltage direct current sending-end power grid, wherein the near zone is used to indicate an area in the ultra-high voltage direct current sending-end power grid whose electrical distance to a converter station is less than a predetermined distance; a first model construction module, used to construct a reactive power demand model of the converter station based on the operation control parameters, wherein the reactive power demand model is used to indicate changes in reactive power demand of the converter station when the ultra-high voltage direct current sending-end power grid is in a direct current blocking state; a second model construction module , used to construct a capacity coordination optimization model of the synchronous condenser in the UHV DC sending-end power grid based on the reactive power demand model, wherein the capacity coordination optimization model is used to coordinate the reactive power output of the synchronous condenser in a steady-state or transient operation scenario under the influence of a preset objective function and constraints; a result determination module, used to obtain a capacity optimization result of the synchronous condenser based on the capacity coordination optimization model, wherein the capacity optimization result is used to at least indicate the number of static reactive compensation devices put into operation in the UHV DC sending-end power grid under transient operation conditions, and the reactive power output of the synchronous condenser.

[0007] According to another aspect of an embodiment of the present invention, a non-volatile storage medium is provided, wherein the non-volatile storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded by a processor and executing any one of the synchronous condenser capacity optimization methods.

[0008] According to another aspect of an embodiment of the present invention, there is also provided an electronic device, comprising one or more processors and a memory, wherein the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement any one of the synchronous phase condenser capacity optimization methods.

[0009] According to another aspect of an embodiment of the present invention, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps of any one of the synchronous phase condenser capacity optimization methods are implemented.

[0010] In an embodiment of the present invention, by obtaining the operation control parameters of the near area of ​​the UHV DC sending-end power grid, wherein the near area is used to indicate an area in the UHV DC sending-end power grid whose electrical distance to the converter station is less than a predetermined distance; based on the operation control parameters, a reactive power demand model of the converter station is constructed, wherein the reactive power demand model is used to indicate the change in reactive power demand of the converter station when the UHV DC sending-end power grid is in a DC blocking state; based on the reactive power demand model, a capacity coordination optimization model of the synchronous phase regulator in the UHV DC sending-end power grid is constructed, wherein the capacity coordination optimization model is used to coordinate the synchronous phase regulator in a steady-state or transient operation scenario under the influence of a preset objective function and constraints. reactive power output; based on the capacity coordination optimization model, the capacity optimization result of the synchronous condenser is obtained, wherein the capacity optimization result is at least used to indicate the number of put-in-use groups of static reactive compensation equipment in the UHV DC sending-end power grid under transient operating conditions, and the reactive power output by the synchronous condenser, so as to achieve the purpose of constructing a reactive power demand model that simultaneously considers the reactive power output of the synchronous condenser in steady-state or transient operating scenarios to optimize the capacity of the synchronous condenser, thereby achieving the technical effect of improving the accuracy and pertinence of the capacity optimization of the synchronous condenser, and then improving the reactive compensation effect, thereby solving the technical problem that the synchronous condenser capacity optimization method in the related art does not take into account comprehensive factors, the capacity optimization effect is poor, and the reactive compensation effect is poor. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0012] Figure 1 is a flow chart of a synchronous condenser capacity optimization method according to an embodiment of the present invention;

[0013] Figure 2 is an optional reactive power balance schematic diagram according to an embodiment of the present invention;

[0014] Figure 3 is a flow chart of an optional synchronous condenser capacity optimization method according to an embodiment of the present invention;

[0015] Figure 4 is a schematic diagram of a near-zone structure of an optional ultra-high voltage direct current transmission system according to an embodiment of the present invention;

[0016] Figure 5 is a schematic diagram comparing transient overvoltage conditions in two modes according to an embodiment of the present invention;

[0017] Figure 6is a schematic diagram of reactive power output of a single synchronous phase condenser according to an optional embodiment of the present invention;

[0018] Figure 7 is a schematic diagram of a synchronous condenser capacity optimization device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0020] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0021] First, to facilitate understanding of the embodiments of the present invention, some terms or nouns involved in the present invention are explained below:

[0022] Ultra High Voltage Direct Current Transmission System (UHVDC) is a system used for long-distance, large-capacity power transmission. It uses direct current instead of alternating current for transmission. Its main advantages include the ability to achieve longer-distance power transmission, reduce line losses, avoid stability issues in the AC system, and be able to connect AC grids of different frequencies. Ultra-high voltage refers to voltage levels of 1000 kV and above for AC and ±800 kV and above for DC. Ultra-high voltage direct current transmission systems are generally designed for voltage levels of ±800 kV or ±1100 kV, or even higher, to achieve greater capacity power transmission.

[0023] At present, the new energy industry has achieved leapfrog development, and the proportion of new energy installed capacity is increasing. However, due to the distribution of geographical resources, some regions have reverse distribution contradictions between "source" and "load", and the transmission of new energy via UHV DC has become the main operation and development mode.

[0024] Affected by the operating characteristics of wind power, photovoltaic power generation, etc., the voltage regulation capability of large-scale new energy bases is relatively weak. The UHV DC transmission system is equipped with phase regulators and static VAR compensation equipment to improve the system voltage support capability. However, while optimizing resource allocation for UHV DC transmission, it also brings many challenges to the safe and stable operation of the high-proportion new energy DC transmission power grid. When the DC bipolar blocking occurs, the static VAR compensation equipment connected to the converter station bus cannot be removed immediately, which will cause a large surplus of reactive power in the converter station, causing transient overvoltage, and the transient voltage will be transmitted to the nearby wind farm, causing some wind turbines to be disconnected from the grid due to high-voltage crossing failure. In severe cases, it may even cause a chain disconnection of wind turbines, which poses a great threat to the safety, stability and transmission capacity of the UHV DC transmission system.

[0025] The steady-state voltage regulation mode of the DC converter station will have a direct impact on the dynamic reactive power support capacity of the system. By optimizing the configuration of the capacity of the phase condenser and the static reactive compensation equipment, the reactive compensation scheme is coordinated and customized, the phase condenser and the static capacitor are replaced with reactive power, the investment in the static reactive compensation equipment is reduced, and the steady-state reactive power output of the phase condenser is increased. This can reduce the impact of the output characteristics of the static compensation equipment on the transient voltage after the DC fault. The coordinated control method of synchronous phase condensers and static capacitors in the related technology is mostly focused on the voltage coordination control and multi-objective reactive voltage control in the transition process after the transient process. The research still focuses on the reactive power support of synchronous phase condensers and static capacitors to the voltage during the fault period, and does not consider the reactive power replacement of dynamic reactive sources and static reactive compensation equipment in the steady-state period and the capacity allocation of synchronous phase condensers. The capacity allocation is counter-targeted and the allocation effect is poor, which leads to poor reactive power compensation effect.

[0026] According to an embodiment of the present invention, a method embodiment of a synchronous phase condenser capacity optimization is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0027] Figure 1 is a flow chart of a synchronous condenser capacity optimization method according to an embodiment of the present invention. Figure 1 As shown, the method comprises the following steps:

[0028] Step S102, obtaining operation control parameters of the UHV DC power grid near the sending end;

[0029] In step S102, first, key operating data related to the power grid at the sending end of the UHV DC transmission system is collected, including but not limited to the active power of the DC system, the power factor angle of the converter, the trigger angle, the overlap angle, etc. At the same time, the rated capacity and the maximum number of switchable groups of the static reactive compensation equipment (such as filters) in the converter station, as well as the capacity and number of synchronous phase regulators connected to the converter station are also obtained. Ensure that all parameters related to the reactive power regulation capability of the power grid are accurately grasped for subsequent analysis and model building. By accurately obtaining these parameters, the dynamic behavior of the power grid after DC blocking can be more accurately simulated, thereby providing a more solid data foundation for optimizing the capacity of synchronous phase regulators.

[0030] Optionally, the near zone is used to indicate an area in the UHV DC sending-end power grid whose electrical distance to the converter station is less than a predetermined distance, that is, a part of the AC power grid that is directly connected to the converter station or has a relatively short electrical distance.

[0031] Optionally, obtaining the operation control parameters of the UHV DC power grid near the sending end includes: obtaining the operation parameters of the UHV DC power grid at the sending end, which may include but are not limited to the active power transmitted at this time, the power factor angle φ of the converter, the trigger angle α, and the overlap angle μ; obtaining the information of the static VAR compensation equipment of the converter station, which may include but are not limited to: the maximum number of switchable groups of static VAR compensation equipment with different rated capacities; obtaining the information of the synchronous condenser connected to the converter station. It may include but is not limited to: the rated capacity of a single synchronous condenser and the number of synchronous condensers.

[0032] Optionally, the reactive power demand of the DC converter station in steady state can be further calculated for subsequent model construction, which may include but is not limited to calculating the reactive power Q consumed by the converter in steady state operation. dc ; Calculate the total reactive power demand Q of the converter station total Specifically, the DC system needs to absorb reactive power from the AC system, that is, the converter is always a reactive load for the AC system. According to the commutation principle, the reactive power consumed by the converter in steady-state operation is expressed by the following formula:

[0033]

[0034]

[0035] Where U di0 Represents the ideal no-load DC voltage of the converter; E 11 Indicates the effective value of the no-load voltage of the valve-side winding of the converter transformer; U d Indicates the DC voltage of each pole; I d Indicates the DC current per pole; X c Represents the commutation reactance of each bridge.

[0036] Calculate the total reactive power demand Qtotal of the converter station. The reactive power balance of the converter station comes from the consumption of the converter of the UHV DC transmission system and the exchange of reactive power with the AC system. Figure 2 is an optional reactive power balance schematic diagram according to an embodiment of the present invention, such as Figure 2 The reactive power demand of the converter station is:

[0037]

[0038] In the formula, Q ac The reactive power demand between the converter station and the AC system is positive when the AC system absorbs reactive power from the converter station, and negative when the AC system transmits reactive power to the converter station. In steady-state operation, Q ac ≈0; U is the per-unit design voltage, and the reference value is the normal operating voltage of the converter station AC bus.

[0039] Step S104, constructing a reactive power demand model of the converter station based on the operation control parameters, wherein the reactive power demand model is used to indicate the change of reactive power demand of the converter station when the UHV DC sending-end power grid is in a DC blocking state;

[0040] In step S104, a mathematical model of reactive power demand of the converter station is established based on the operating characteristics of the UHV DC system in steady state and transient state (after DC blocking). The model takes into account the changes in reactive power demand before and after DC blocking, especially after DC blocking, the reactive power surplus and voltage increase caused by the reduction of reactive power consumption of the converter and the inability of the static VAR compensation equipment to be immediately removed. By constructing a reactive power demand model, the impact of DC blocking events on the reactive power demand of the converter station can be quantified.

[0041] Optionally, the DC blocking state refers to the process in which the control system actively or passively stops the power transmission of the DC system in the UHV DC transmission system due to various reasons (such as equipment failure, protection action, etc.), causing the DC system to switch from a normal operating state to a completely stopped state. In this state, the converter of the DC transmission system will no longer perform the conversion work from AC to DC or DC to AC, and the DC current will drop rapidly to zero. At the same time, the electrical connection between the DC system and the AC system is cut off. The UHV DC transmission end system refers to the power transmission side grid in the UHV DC transmission system. The UHV DC sending end grid specifically refers to the grid that transmits electric energy to the outside through the UHV DC line from the new energy base. It includes converter stations, synchronous phase regulators, static VAR compensation equipment, etc. These devices work together to ensure the stability and power quality of the grid under various operating conditions (including normal operation and fault conditions).

[0042] In an optional embodiment, based on the operation control parameters, a reactive power demand model of the circulating station in the UHV DC sending-end power grid is constructed, including: determining the transient overvoltage of the bus connected to the converter station in the DC blocking state based on the operation control parameters; determining the reactive power respectively output by multiple static reactive compensation devices included in the UHV DC sending-end power grid in the DC blocking state; and constructing a reactive power demand model based on the transient overvoltage of the bus connected to the converter station and the reactive power respectively output by multiple static reactive compensation devices.

[0043] Optionally, by determining the transient overvoltage of the bus connected to the converter station in the DC blocking state based on the operation control parameters, the voltage increase that may occur on the converter station bus when a DC system fault occurs can be more accurately predicted. Determining the reactive power output by multiple static reactive compensation devices (such as filters, capacitor banks, etc.) in the DC blocking state can quantitatively evaluate the contribution of static reactive compensation devices to the transient reactive excess of the system after the UHV DC system fault. Constructing a reactive power demand model based on transient overvoltage and reactive power output by static reactive compensation devices can achieve refined management of the reactive power demand of the converter station, ensuring that the converter station can quickly adjust reactive power during the transient process after the fault, and avoiding the impact of overvoltage on system stability and equipment safety. In the above manner, the reactive power behavior of the converter station can be more accurately controlled and predicted, so as to effectively suppress transient overvoltage after fault events such as DC blocking, improve the stability of the UHV DC sending-end power grid, avoid chain reactions, such as wind turbines disconnecting from the grid due to overvoltage, and ensure the reliable output of new energy and the stable operation of the power system. Clarifying the relationship between the output power of static reactive power compensation equipment and transient overvoltage will help optimize the configuration of reactive power compensation equipment in steady-state and transient scenarios, reduce unnecessary investment in static reactive power compensation equipment, and increase the participation of dynamic reactive power compensation equipment (such as synchronous phase regulators), thereby improving the flexibility and response speed of the system.

[0044] The reactive power demand model can be constructed by, but is not limited to, the following steps:

[0045] Step S1041, deriving the transient overvoltage of the converter station bus after DC blocking.

[0046] After DC blocking, the reactive power consumed by the converter station decreases rapidly as the active power transmitted by DC decreases. Due to the 200 millisecond delay in the operation of the static VAR compensation device, a large amount of reactive power flows into the AC system, causing the voltage of the converter station bus to rise. The voltage rise per unit value of the converter station bus voltage ΔU * It can be approximately expressed as:

[0047]

[0048] Where ΔQ is the reactive power change of the converter station; SC is the short-circuit capacity of the AC system.

[0049] The reactive power output of the static VAR compensation device is related to the voltage at the access point. When the bus voltage of the converter station changes, the reactive power output of the static VAR compensation device will also change. The reactive power output of a single static VAR compensation device at this time is:

[0050]

[0051] In the formula, Q Ci,S is the reactive output power of a single static VAR compensation device of type i after a fault, U N It should refer to the rated voltage of the static VAR compensation equipment.

[0052] At this time, the reactive power change is:

[0053]

[0054] In the formula, k c,i It indicates the number of groups of type i static VAR compensation equipment put into operation in steady state, and n indicates that there are static VAR compensation equipment with different capacities in total.

[0055] Substituting equation (3) and equation (2) into equation (1), we can obtain:

[0056]

[0057] According to equation (4), the voltage rise per unit value of the converter station bus voltage after DC blocking is:

[0058]

[0059] Then the transient overvoltage of the bus connected to the converter station after DC blocking can be expressed by the following formula.

[0060]

[0061] Step S1042, calculate the reactive power output by the static VAR compensation device. The reactive power output by the static VAR compensation device is proportional to the square of the voltage at the access location. The reactive power Q output by the static VAR compensation device during DC blocking is calculated based on the bus transient overvoltage of the converter station obtained in step S1042. STATIC,S .

[0062]

[0063] Step S1043, establish a reactive power demand model for the converter station when the DC is blocked. The main reason for the transient overvoltage after the UHV DC is blocked is that after the DC is blocked, the reactive power consumed by the converter is 0, and the static reactive power compensation equipment connected to the converter station busbar cannot be removed in time in steady state, resulting in reactive power surplus. Therefore, the reactive power demand Q of the converter station when the DC is blocked is total,s It can be expressed as follows.

[0064]

[0065] Step S106, based on the reactive power demand model, constructing a capacity coordination optimization model of the synchronous condenser in the UHV DC sending-end power grid, wherein the capacity coordination optimization model is used to coordinate the reactive power output of the synchronous condenser in a steady-state or transient operation scenario under the influence of a preset objective function and constraint conditions;

[0066] In step S106, a mathematical model is established in combination with the reactive power demand model to optimize the capacity configuration and reactive output of the synchronous condenser. The objective function of the model may be, but is not limited to, minimizing the transient overvoltage of the converter station after DC blocking. The constraints may involve the reactive output capacity of the synchronous condenser and the static reactive compensation equipment, as well as the reactive balance and bus voltage operation requirements of the converter station. The construction of the optimization model ensures that the synchronous condenser can adjust the reactive output in a timely manner according to the actual needs of the power grid to reduce the overvoltage problem caused by DC blocking. This not only helps to improve the stability of the DC sending end system, but also helps to optimize the configuration of the reactive compensation equipment and improve the operating efficiency of the power grid.

[0067] Optionally, the steady state is a normal operating state, and the transient state is a fault response state.

[0068] In an optional embodiment, based on the reactive power demand model, a capacity coordination optimization model of synchronous phase condensers in the UHV DC sending-end power grid is constructed, including: based on the reactive power demand model, constructing an objective function as follows: the transient overvoltage of the converter station caused by DC blocking is minimized; constructing a reactive power reserve model of the synchronous phase condensers, wherein the reactive power reserve model is used to indicate the value of the reactive power reserve capacity of the synchronous phase condensers under different operating conditions; determining the constraints as follows: the reactive power balance constraint of the reactive power demand of the converter station in a steady-state operating state, and the bus voltage operation constraint in a steady-state operating state; and constructing a capacity coordination optimization model based on the objective function, the reactive power reserve model and the constraints.

[0069] It can be understood that the objective function is set to minimize the transient overvoltage of the converter station caused by the occurrence of DC blocking, which can achieve the purpose of suppressing the transient overvoltage caused by DC blocking. By optimizing the reactive power regulation of the synchronous condenser, it is ensured that the voltage fluctuation of the converter station is minimized in the event of a fault, thereby improving the stability of the system. The constraints set include steady-state reactive balance constraints and steady-state bus voltage operation constraints. These constraints can ensure that under normal operating conditions, the reactive power of the system remains balanced and the bus voltage of the converter station operates within a safe range. By integrating the objective function, reactive reserve model and constraints, a capacity coordination optimization model is constructed, which enables the algorithm to solve the optimal reactive output of the synchronous condenser and the switching strategy of the static reactive compensation equipment, thereby realizing the reasonable distribution of reactive power of the condenser and static compensation in steady-state and transient scenarios.

[0070] In an optional embodiment, a reactive power reserve model of a synchronous condenser is constructed, including: constructing a leading phase reactive power reserve model of the synchronous condenser, and a lagging phase reactive power reserve model of the synchronous condenser; constructing a dynamic reactive reserve power constraint of a converter station as follows: in a steady-state operation state, the leading phase reactive power reserve capacity of the synchronous condenser is greater than or equal to a preset first capacity, and the lagging phase reactive power reserve capacity is greater than a preset second capacity; based on the leading phase reactive power reserve model, the lagging phase reactive power reserve model and the dynamic reactive reserve power constraint, a reactive reserve model is constructed.

[0071] It can be understood that by setting dynamic reactive reserve power constraints, it can ensure that the system has sufficient reactive reserves during steady-state operation, and can quickly absorb or generate reactive power when faults such as DC blocking occur, suppress transient overvoltage, and maintain system voltage stability. The advanced and delayed phase reactive reserve models constructed enable the phase regulator to provide optimal reactive power under different operating conditions, thereby avoiding waste of resources when reactive output is not required, and ensuring that sufficient capacity can be provided when reactive support is required. The establishment of the phase regulator reactive reserve model enables the system to flexibly adjust the output of reactive power when facing various operating scenarios, which can not only ensure voltage quality during steady-state operation, but also improve the system's recovery speed in transient events, and increase the system's adaptability to high-proportion access to new energy. Through the optimization of the phase regulator reactive reserve model, the voltage level of the converter station can be more effectively controlled, and the risk of new energy units being disconnected from the grid due to voltage problems can be reduced, thereby improving the absorption capacity of new energy and the overall operating efficiency of the power system.

[0072] In an optional embodiment, the reactive balance constraint is used to indicate that the total reactive power demand of the converter station is equal to the sum of the reactive power output by the synchronous phase-converter and the reactive power output by the static VAR compensation device; the bus voltage operation constraint is used to indicate that under steady-state operating conditions, each bus voltage node in the vicinity of the converter station operates within a preset voltage range.

[0073] It can be understood that reactive power balance constraints can ensure that under steady-state operating conditions, the total reactive power demand of the converter station can be met by both the synchronous phase condenser and the static VAR compensation equipment. This means that by adjusting the reactive output of the synchronous phase condenser and controlling the switching of the static VAR compensation equipment, the reactive power state of the converter station can be accurately controlled to avoid excess or insufficient reactive power, thereby maintaining the stable operation of the power grid. In transient processes such as DC interlocking, by implementing reactive power balance in advance under steady-state conditions, transient overvoltages caused by the inability of reactive compensation equipment to respond immediately can be reduced, thereby ensuring the voltage stability of the UHV DC sending-end system under different operating conditions, and especially improving the transient voltage control capability of the system after DC interlocking.

[0074] The bus voltage operation constraint can ensure that under steady-state operating conditions, each bus voltage node near the converter station operates within the preset voltage range, which helps maintain the voltage level of the entire power grid and avoid the impact of abnormal voltage fluctuations on power equipment and system operation. By setting a reasonable bus voltage operating range, the safe and economical operation of the power system can be ensured. In the transient process after DC blocking, the dynamic reactive response of the synchronous phase regulator can quickly adjust the bus voltage to avoid the voltage rising beyond the allowable range, thereby preventing the wind turbine from disconnecting from the grid due to high-voltage ride-through failure, reducing the risk of chain disconnection accidents, and improving the stability and reliability of the new energy sending-end system.

[0075] Optionally, the capacity coordination optimization model may be constructed in the following ways, but is not limited to:

[0076] Step S1061, establish an objective function with the goal of minimizing the transient overvoltage of the converter station caused by DC blocking. This goal can be converted into: minimizing the reactive power surplus after the synchronous condenser participates in regulation. That is:

[0077]

[0078] In the formula, Q t ' otal,S It represents the reactive power surplus after the synchronous condenser participates in regulation; Q SC,i,jx Represents the leading phase reactive reserve capacity of synchronous generator i.

[0079] Step S1062, establishing a reactive power reserve model of the synchronous condenser, specifically including:

[0080] Step S10621, the phase-leading reactive power reserve model of the synchronous condenser. The phase-leading reactive power of the synchronous condenser is usually half of the rated capacity. When the reactive output of the generator is positive in steady state, the phase-leading reactive reserve power of the condenser remains unchanged. When the reactive output of the generator is negative in steady state, the phase-leading reactive reserve will be reduced.

[0081]

[0082] In the formula, Q SC,i It represents the reactive power output of synchronous condenser i in steady state.

[0083] Step S10622, the delayed phase reactive power reserve model of the synchronous condenser. When the reactive output of the generator is positive in steady state, the delayed phase reactive power reserve of the condenser decreases, and when the reactive output power of the generator is negative in steady state, the delayed phase reactive power reserve of the condenser remains unchanged.

[0084]

[0085] In the formula, Q SC,i,cx represents the delayed-phase reactive power reserve capacity of synchronous generator i;

[0086] Step S10623, dynamic reactive reserve power constraint of the converter station. When the power system is in operation, it should be ensured that the system has a certain reactive reserve capacity to respond to a system failure and quickly generate / absorb reactive power to restore the system to stability.

[0087] The DC converter station area mainly relies on synchronous phase regulators to provide dynamic reactive power reserves.

[0088]

[0089] Step S1063, establish reactive power balance constraints for reactive power demand of converter stations in steady state. In steady state, synchronous condensers and static reactive power compensation equipment jointly provide reactive power for DC converter stations.

[0090]

[0091] Step S1064, establish bus voltage operation constraints during steady-state operation. In steady state, each bus voltage node near the converter station should operate within the required voltage operation range.

[0092] U imin ≤U i ≤U imax ,i=1,…,N

[0093] Where U i is the steady-state operating value of the bus voltage at node i near the converter station; U imin , U imax They respectively represent the minimum and maximum values ​​of the allowable range of the bus voltage at node i.

[0094] Step S108, based on the capacity coordination optimization model, obtain the capacity optimization result of the synchronous phase condenser, wherein the capacity optimization result is at least used to indicate the number of static reactive power compensation equipment put into operation in the UHV DC sending-end power grid under transient operating conditions, and the reactive power output by the synchronous phase condenser.

[0095] In step S108, an appropriate optimization algorithm, such as the Differential Evolution and Seagull Optimization (DESO) algorithm, is used to solve the capacity coordination optimization model constructed above, so as to obtain the optimal configuration of the synchronous phase regulator in the UHV DC sending-end power grid, including the number of static reactive power compensation equipment put into operation under steady-state operation conditions, and the reactive power output value of the synchronous phase regulator under steady-state and transient operation scenarios. The optimization results obtained by solving the model can guide the reasonable configuration of the reactive power compensation equipment of the converter station, and ensure that under transient conditions such as DC blocking, the dynamic adjustment of the synchronous phase regulator can effectively suppress overvoltage, avoid serious consequences such as wind turbines being disconnected from the grid, and ensure the safe and stable operation of the power grid. In addition, the optimized capacity allocation also helps to improve the transmission capacity of the UHV DC system and promote the consumption of new energy.

[0096] In an optional embodiment, based on the capacity coordination optimization model, the capacity optimization result of the synchronous phase condenser is obtained, including: constructing an initial population, wherein each individual in the initial population represents a set of control variables, and the set of control variables includes the number of static VAR compensation devices put into operation, and the reactive power output by the synchronous phase condenser; based on the initial population, using improved differential evolution and seagull optimization algorithm to solve the capacity coordination optimization model to obtain the capacity optimization result of the synchronous phase condenser.

[0097] Optionally, the DESO algorithm is a randomized parallel direct global search algorithm that is simple and easy to use in solving nonlinear models, and can ensure the effectiveness and computational efficiency of the solution. However, when dealing with high-dimensional, nonlinear complex problems, the standard DESO algorithm cannot guarantee accurate and timely finding of the global optimal solution, and is prone to falling into local optimality. Therefore, this embodiment can use a double mutation strategy based on population similarity and an improved DESO algorithm with adaptive crossover probability to solve the model. Among them, the double mutation strategy ensures the diversity of the population, making it difficult for the model to fall into the local optimal solution; the adaptive crossover probability can adaptively adjust the crossover probability of the individual according to the individual's excellence, which is conducive to the movement of the population individuals to the individuals with successful updates, thereby improving the convergence of the algorithm.

[0098] Optionally, the specific steps of using improved differential evolution and Seagull optimization algorithm to solve the capacity coordination optimization model are as follows:

[0099] S1081, input DESO system parameters and algorithm parameters. Algorithm parameters include maximum evolutionary number G, population size MP, individual dimension D, scaling factor S and crossover probability CR. System parameters include converter station node voltage operating range, rated capacity and number of synchronous condensers and static VAR compensation equipment, and reactive power demand of converter stations in steady state.

[0100] S1082, population initialization. The population is initialized. Each individual in the population represents a set of control variables, including the number of static VAR compensation equipment input groups and the reactive power output of each synchronous condenser in steady state.

[0101] S1083, calculate fitness. Calculate the fitness of each individual in the population and select the individual with the best fitness.

[0102] S1084, processing constraints. When an individual does not meet the constraints of the model, its fitness value is modified to eliminate it.

[0103] S1085, implement a mutation operation using a double mutation strategy, calculate population similarity, and select an appropriate mutation strategy based on the current population similarity.

[0104] S1086, Crossover and Selection. Perform population crossover and select a new generation of population.

[0105] S1087, adaptively adjust the crossover probability. Adaptively adjust the crossover probability according to the individual excellence, and retain the crossover probability of excellent individuals to the next generation.

[0106] S1088, repeat steps S1083 to S1087 until the maximum evolution generation is reached, and output the number of static VAR compensation equipment input groups and the reactive power output by each synchronous phase regulator in steady state.

[0107] In the above steps S102 to S108, by obtaining the operation control parameters of the UHV DC sending-end power grid near the area, the method can more accurately analyze the reactive power demand of the converter station, especially in the extreme case of DC blocking. This helps to improve the stability of the new energy weak sending-end system, reduce the risk of wind turbines being disconnected from the grid due to transient overvoltage, and prevent the occurrence of chain disconnection accidents. The constructed reactive power demand model and capacity coordination optimization model take into account the time constant and capacity regulation characteristics of various reactive compensation devices in the converter station, and can maximize the effect of various reactive compensation devices in steady-state and transient scenarios. The configuration structure of the new energy DC sending-end system is thereby optimized, so that the system has better reactive support under various operating conditions. By optimizing the reactive output of the synchronous condenser, the transient overvoltage caused by the inability to timely remove the static reactive compensation equipment after DC blocking is reduced, which helps to improve the transmission capacity of the UHV DC, thereby increasing the penetration rate of new energy, and has a positive effect on promoting the transformation of energy production and consumption. By coordinating and optimizing the reactive capacity of synchronous phase condensers in steady-state and transient operation scenarios, the optimal coordination of dynamic reactive sources (such as synchronous phase condensers) and static reactive compensation equipment (such as static reactive compensation equipment) is achieved, which improves the system's ability to suppress transient overvoltages, reduces the impact on equipment, and ensures safe and stable operation of the system.

[0108] Based on the above embodiments and optional embodiments, the present invention proposes an optional implementation mode: Figure 3 is a flow chart of an optional synchronous phase condenser capacity optimization method according to an embodiment of the present invention. Figure 3 As shown, the method includes:

[0109] S1, obtaining the near-area operation control parameters of the UHV DC sending-end power grid, including the following steps:

[0110] S11: Acquire the operating parameters of the UHV DC sending-end power grid, where the operating parameters may include but are not limited to the active power transmitted at this time, the power factor angle φ of the converter, the trigger angle α, and the overlap angle μ;

[0111] S12: Acquiring information of the static VAR compensation equipment of the converter station, which may include but is not limited to: the maximum number of switchable groups of static VAR compensation equipment of different rated capacities;

[0112] S13: Acquire information of synchronous condensers connected to the converter station, which may include but are not limited to: the rated capacity of a single synchronous condenser and the number of synchronous condensers.

[0113] S2, calculating the reactive power demand of the DC converter station in steady state, includes the following steps:

[0114] S21: Calculate the reactive power Q consumed by the DC system during steady-state operation dc ;

[0115] S22: Calculate the total reactive power demand Q of the converter station total .

[0116] S3, establishing a reactive power demand model of the converter station during DC blocking, including the following steps:

[0117] S31: Derivation of transient overvoltage U of the busbar connected to the converter station after DC blocking S ;

[0118] S32: Calculate the reactive power Q output by the static VAR compensation device STATIC,S ;

[0119] S33: Establish reactive power demand model Q of converter station during DC blocking total,S .

[0120] S4, constructing a steady-state / transient capacity coordination optimization model for synchronous condensers, including the following steps:

[0121] S41: Establishing an objective function with the goal of minimizing the transient overvoltage of the converter station caused by DC blocking as the goal, which can be converted into: minimizing the reactive power surplus after the synchronous condenser participates in the reactive power regulation of the converter station;

[0122] S42: Establishing a reactive power reserve model of a synchronous condenser, including a leading phase reactive power reserve model of a synchronous condenser, a lagging phase reactive power reserve model of a synchronous condenser, and a dynamic reactive power reserve power constraint of a converter station;

[0123] S43: establishing reactive power balance constraints for reactive power demand of converter stations in steady state;

[0124] S44: Establish bus voltage operation constraints during steady-state operation.

[0125] S5, solving the steady-state / transient capacity coordination optimization model of the synchronous condenser, including the following steps:

[0126] S51: The improved DESO algorithm is used to solve the steady-state / transient capacity coordination optimization model of the synchronous condenser, the number of static VAR compensation equipment put into operation when the output is steady-state, and the reactive power output of each synchronous condenser when it is steady-state.

[0127] Based on the above embodiments and optional embodiments, the present invention also proposes a method based on Figure 3 The specific implementation of the synchronous phase condenser capacity optimization method shown in the figure, the method specifically includes:

[0128] S1: Obtain the near-area operation control parameters of the UHV DC transmission-end power grid, specifically:

[0129] Figure 4is a schematic diagram of a near-area structure of an optional ultra-high voltage direct current transmission system according to an embodiment of the present invention, such as Figure 4 As shown, the rated voltage is ±800kV, the rated transmission power is 8000MW, the active power transmitted by the DC transmission is 6000MW, the trigger angle is 16.4°, and the commutation angle is 22°. The converter station has a total of 16 sets of static VAR compensation equipment, which are of two types, 11 sets of 265Mvar filters and 5 sets of 325Mvar filters, with a rated voltage of 800kV. In addition, there are 2 new generation synchronous phase regulators of 300MVA.

[0130] S2: Calculate the reactive power demand of the DC converter station in steady state, specifically:

[0131] According to the UHV DC operating parameters and the reactive power calculation formula consumed by the converter in step S1, the reactive power consumed by the converter is 3294Mvar. If it is assumed that the AC system provides 0Mvar reactive power, the reactive power demand of the DC converter station is 3294Mvar. If 10 groups of 265Mvar filters and 2 groups of 325Mvar filters are selected, the rated capacity of the filters put into use is 3300Mvar. The reactive power demand of the DC converter station in steady state is 3300Mvar.

[0132] S3: Establish the reactive power demand model of the converter station during DC blocking, specifically:

[0133] The reactive power demand model of the converter station during DC blocking is established. The short-circuit capacity of the busbar of the UHV DC transmission converter station is 36040MVA.

[0134] S4: Construct a steady-state / transient capacity coordination optimization model for synchronous condensers, specifically:

[0135] The objective function is established with the goal of minimizing the transient overvoltage of the converter station caused by DC blocking, and the goal is converted into: the reactive surplus after the synchronous condenser participates in the regulation is minimized. The reactive reserve model of the synchronous condenser is established; the reactive balance constraint of the reactive demand of the converter station in steady state is established, and the bus voltage operation constraint in steady state operation is established. The bus voltage of the converter station in the steady state in the model is kept within 750kV~800kV.

[0136] S5: Solve the steady-state / transient capacity coordination optimization model of synchronous condensers, specifically:

[0137] The improved DESO algorithm is used to solve the steady-state / transient capacity coordination optimization model of the synchronous condenser, and the output results show that in steady state, 5 groups of 265Mvar filters and 5 groups of 325Mvar filters are put into use. At the same time, the output reactive power of the synchronous condenser in steady state is 170Mvar.

[0138] In order to reflect the effectiveness of the proposed coordinated optimization of the reactive power regulation capacity of the phase condenser in steady-state and transient scenarios in suppressing the transient voltage caused by DC blocking, a comparison is made with the calculation example without this method, that is, the synchronous phase condenser does not generate reactive power in steady state, and the reactive power required by the converter station is provided by the static reactive compensation equipment, and 10 groups of 265Mvar filters and 2 groups of 325Mvar filters calculated in step S1 are invested. The comparison of the two methods in steady state is shown in the following table.

[0139] Table 1 Comparison results of the synchronous condenser and the input filter in steady state of the two methods

[0140]

[0141]

[0142] In PSASP, a simulation is performed to verify that the DC bipolar blocking occurs at 1 second. Figure 5 is a schematic diagram comparing transient overvoltage conditions in two ways according to an embodiment of the present invention, Figure 6 FIG. 1 is a schematic diagram of reactive power output of a single synchronous phase condenser according to an optional embodiment of the present invention. Figure 5 The reactive power output of a single synchronous condenser is shown in the attached figure. Figure 6 As shown. Figure 5 It can be seen that after a DC blocking fault occurs, the method proposed in this embodiment has a stronger ability to suppress transient overvoltage, and can reduce the transient overvoltage by 0.013 percentage units (pu).

[0143] This embodiment can achieve at least one of the following effects: 1) By coordinating and optimizing the reactive capacity of synchronous phase regulators in steady-state / transient scenarios, the excellent dynamic regulation performance of phase regulators is fully utilized, and the transient overvoltage problem caused by UHV DC blocking is effectively suppressed, thereby improving the stability of the weak-transmission-end system of new energy; 2) By considering the time constant and capacity regulation characteristics of various reactive compensation equipment in the converter station in detail, the effects of various reactive compensation equipment are guaranteed in steady-state and transient scenarios. The configuration structure of the new energy DC transmission-end system is optimized; 3) It can effectively improve the UHV DC transmission capacity, help improve the penetration rate of new energy, and help my country promote the transformation of energy production and consumption.

[0144] In this embodiment, a synchronous phase condenser capacity optimization device is also provided, which is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the terms "module" and "device" can be a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0145] According to an embodiment of the present invention, there is also provided an apparatus embodiment for implementing the above-mentioned synchronous phase condenser capacity optimization method. Figure 7 is a schematic diagram of the structure of a synchronous phase condenser capacity optimization device according to an embodiment of the present invention. Figure 7 As shown, the synchronous condenser capacity optimization device comprises: a parameter acquisition module 700, a first model construction module 702, a second model construction module 704, and a result determination module 706, wherein:

[0146] The parameter acquisition module 700 is used to acquire the operation control parameters of the near zone of the UHV DC sending-end power grid, wherein the near zone is used to indicate the area in the UHV DC sending-end power grid whose electrical distance to the converter station is less than a predetermined distance;

[0147] The first model building module 702 is used to build a reactive power demand model of the converter station based on the operation control parameters, wherein the reactive power demand model is used to indicate the reactive power demand change of the converter station when the UHV DC sending-end power grid is in a DC blocking state;

[0148] The second model building module 704 is used to build a capacity coordination optimization model of the synchronous condenser in the UHV DC sending-end power grid based on the reactive power demand model, wherein the capacity coordination optimization model is used to coordinate the reactive power output of the synchronous condenser in a steady-state or transient operation scenario under the influence of a preset objective function and constraint conditions;

[0149] The result determination module 706 is used to obtain the capacity optimization result of the synchronous phase regulator based on the capacity coordination optimization model, wherein the capacity optimization result is at least used to indicate the number of static reactive power compensation equipment put into operation in the UHV DC sending-end power grid under transient operating conditions, and the reactive power output by the synchronous phase regulator.

[0150] It should be noted that the above modules can be implemented by software or hardware. For example, for the latter, it can be implemented in the following ways: the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0151] It should be noted that the parameter acquisition module 700, the first model building module 702, the second model building module 704, and the result determination module 706 correspond to steps S102 to S108 in the embodiment, and the examples and application scenarios implemented by the modules and the corresponding steps are the same, but are not limited to the contents disclosed in the above embodiments. It should be noted that the modules as part of the device can be run in a computer terminal.

[0152] It should be noted that the optional or preferred implementation of this embodiment can refer to the relevant description in the embodiment, which will not be repeated here.

[0153] The above-mentioned synchronous phase condenser capacity optimization device may also include a processor and a memory. The above-mentioned parameter acquisition module 700, the first model construction module 702, the second model construction module 704, the result determination module 706, etc. are all stored in the memory as program modules, and the processor executes the above-mentioned program modules stored in the memory to realize corresponding functions.

[0154] The processor includes a kernel, which retrieves the corresponding program module from the memory. The kernel may be one or more. The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. The memory includes at least one memory chip.

[0155] According to an embodiment of the present application, an embodiment of a non-volatile storage medium is also provided. Optionally, in this embodiment, the non-volatile storage medium includes a stored program, wherein when the program is executed, the device where the non-volatile storage medium is located is controlled to execute any of the above-mentioned synchronous phase condenser capacity optimization methods.

[0156] Optionally, in this embodiment, the non-volatile storage medium may be located in any computer terminal in a computer terminal group in a computer network, or in any mobile terminal in a mobile terminal group, and the non-volatile storage medium includes a stored program.

[0157] Optionally, when the program is running, the device where the non-volatile storage medium is located is controlled to perform the following functions: obtaining operation control parameters of the near area of ​​the UHV DC sending-end power grid, wherein the near area is used to indicate an area in the UHV DC sending-end power grid where the electrical distance to the converter station is less than a predetermined distance; constructing a reactive power demand model of the converter station based on the operation control parameters, wherein the reactive power demand model is used to indicate changes in the reactive power demand of the converter station when the UHV DC sending-end power grid is in a DC blocking state; constructing a capacity coordination optimization model of synchronous phase regulators in the UHV DC sending-end power grid based on the reactive power demand model, wherein the capacity coordination optimization model is used to coordinate the reactive power output of synchronous phase regulators in steady-state or transient operation scenarios under the influence of preset objective functions and constraints; obtaining capacity optimization results of synchronous phase regulators based on the capacity coordination optimization model, wherein the capacity optimization results are used at least to indicate the number of static reactive compensation equipment put into operation in the UHV DC sending-end power grid under transient operation conditions, and the reactive power output of the synchronous phase regulators.

[0158] According to an embodiment of the present application, an embodiment of a processor is also provided. Optionally, in this embodiment, the processor is used to run a program, wherein when the program is run, any of the above-mentioned synchronous condenser capacity optimization methods is executed.

[0159] According to an embodiment of the present application, an embodiment of a computer program product is also provided. When executed on a data processing device, it is suitable for executing a program that initializes any of the steps of the synchronous phase condenser capacity optimization method described above.

[0160] Optionally, the above-mentioned computer program product, when executed on a data processing device, is suitable for executing a program that is initialized with the following method steps: obtaining operation control parameters of a near zone of an ultra-high voltage direct current (UHVDC) sending-end power grid, wherein the near zone is used to indicate an area in the ultra-high voltage direct current (UHVDC) sending-end power grid where the electrical distance to the converter station is less than a predetermined distance; constructing a reactive power demand model of the converter station based on the operation control parameters, wherein the reactive power demand model is used to indicate changes in the reactive power demand of the converter station when the ultra-high voltage direct current (UHVDC) sending-end power grid is in a DC blocking state; constructing a capacity coordination optimization model of synchronous phase regulators in the ultra-high voltage direct current (UHVDC) sending-end power grid based on the reactive power demand model, wherein the capacity coordination optimization model is used to coordinate the reactive power output of synchronous phase regulators in steady-state or transient operation scenarios under the influence of preset objective functions and constraints; obtaining capacity optimization results of synchronous phase regulators based on the capacity coordination optimization model, wherein the capacity optimization results are used at least to indicate the number of static reactive compensation devices put into operation in the ultra-high voltage direct current (UHVDC) sending-end power grid under transient operation conditions, and the reactive power output by the synchronous phase regulators.

[0161] An embodiment of the present invention provides an electronic device, which includes a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, the following steps are implemented: obtaining operation control parameters of a near zone of an ultra-high voltage direct current (UHVDC) sending-end power grid, wherein the near zone is used to indicate an area in the ultra-high voltage direct current (UHVDC) sending-end power grid where the electrical distance to a converter station is less than a predetermined distance; constructing a reactive power demand model of the converter station based on the operation control parameters, wherein the reactive power demand model is used to indicate the change in reactive power demand of the converter station when the ultra-high voltage direct current (UHVDC) sending-end power grid is in a DC blocking state; constructing a capacity coordination optimization model of synchronous condensers in the ultra-high voltage direct current (UHVDC) sending-end power grid based on the reactive power demand model, wherein the capacity coordination optimization model is used to coordinate the reactive power output of synchronous condensers in steady-state or transient operation scenarios under the influence of preset objective functions and constraints; obtaining a capacity optimization result of the synchronous condensers based on the capacity coordination optimization model, wherein the capacity optimization result is used at least to indicate the number of static reactive compensation devices put into operation in the ultra-high voltage direct current (UHVDC) sending-end power grid under transient operation conditions, and the reactive power output by the synchronous condensers.

[0162] The above sequence of the embodiments of the present invention is for description only and does not represent the superiority or inferiority of the embodiments.

[0163] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0164] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the above modules can be a logical function division. There may be other division methods in actual implementation, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, modules or indirect coupling or communication connection of modules, which can be electrical or other forms.

[0165] The modules described above as separate components may or may not be physically separated, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed on multiple modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment.

[0166] In addition, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of software functional modules.

[0167] If the above-mentioned integrated module is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable non-volatile storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a non-volatile storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of the various embodiments of the present invention. The aforementioned non-volatile storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0168] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A synchronous phase condenser capacity optimization method, characterized in that: include: Acquiring operation control parameters of a near zone of a UHV DC sending-end power grid, wherein the near zone is used to indicate a zone in the UHV DC sending-end power grid whose electrical distance to a converter station is less than a predetermined distance; Based on the operation control parameters, construct a reactive power demand model of the converter station, wherein the reactive power demand model is used to indicate the change of reactive power demand of the converter station when the UHV DC sending-end power grid is in a DC blocking state; Based on the reactive power demand model, a capacity coordination optimization model of the synchronous condenser in the UHV DC sending-end power grid is constructed, wherein the capacity coordination optimization model is used to coordinate the reactive power output of the synchronous condenser in a steady-state or transient operation scenario under the influence of a preset objective function and constraints; Based on the capacity coordination optimization model, a capacity optimization result of the synchronous phase condenser is obtained, wherein the capacity optimization result is at least used to indicate the number of static VAR compensation devices put into operation in the UHV DC sending-end power grid under transient operating conditions, and the reactive power output by the synchronous phase condenser.

2. The method according to claim 1, characterized in that The step of constructing a reactive power demand model of a circulating current station in the UHV DC sending-end power grid based on the operation control parameters includes: determining, based on the operation control parameters, a transient overvoltage of a busbar connected to the converter station in the DC blocking state; Determining the reactive power respectively output by a plurality of static reactive power compensation devices included in the UHV DC sending-end power grid in the DC blocking state; The reactive power demand model is constructed based on the transient overvoltage of the busbar connected to the converter station and the reactive power respectively output by the multiple static reactive power compensation devices.

3. The method according to claim 1, characterized in that The method of constructing a capacity coordination optimization model of synchronous condensers in the UHV DC sending-end power grid based on the reactive power demand model includes: Based on the reactive power demand model, the objective function is constructed as follows: the transient overvoltage of the converter station caused by the occurrence of the DC blocking is the lowest; Constructing a reactive power reserve model of the synchronous condenser, wherein the reactive power reserve model is used to indicate the value of the reactive power reserve capacity of the synchronous condenser under different operating conditions; Determine the constraint conditions as: reactive power balance constraint of reactive power demand of converter station in steady-state operation state, and bus voltage operation constraint in steady-state operation state; Based on the objective function, the reactive power reserve model and the constraint conditions, the capacity coordination optimization model is constructed.

4. The method according to claim 3, characterized in that The step of constructing the reactive power reserve model of the synchronous condenser comprises: Constructing a leading phase reactive power reserve model of the synchronous condenser and a lagging phase reactive power reserve model of the synchronous condenser; The dynamic reactive reserve power constraint of the converter station is constructed as follows: in a steady-state operation state, the leading phase reactive reserve capacity of the synchronous condenser is greater than or equal to a preset first capacity, and the lagging phase reactive power reserve capacity is greater than a preset second capacity; The reactive power reserve model is constructed based on the leading phase reactive power reserve model, the lagging phase reactive power reserve model and the dynamic reactive reserve power constraint.

5. The method according to claim 3, characterized in that: The reactive power balance constraint is used to indicate that the total reactive power demand of the converter station is equal to the sum of the reactive power output by the synchronous condenser and the reactive power output by the static VAR compensation device; The bus voltage operation constraint is used to indicate that under the steady-state operation condition, each bus voltage node in the vicinity of the converter station operates within a preset voltage range.

6. The method according to any one of claims 1 to 5, characterized in that The obtaining of the capacity optimization result of the synchronous condenser based on the capacity coordination optimization model includes: Constructing an initial population, wherein each individual in the initial population represents a set of control variables, and the set of control variables includes the number of input groups of the static VAR compensation device and the reactive power output by the synchronous condenser; Based on the initial population, the improved differential evolution and Seagull optimization algorithms are used to solve the capacity coordination optimization model to obtain the capacity optimization result of the synchronous condenser.

7. A synchronous phase condenser capacity optimization device, characterized in that: include: A parameter acquisition module, used to acquire operation control parameters of a near zone of a UHV DC sending-end power grid, wherein the near zone is used to indicate a zone in the UHV DC sending-end power grid whose electrical distance to a converter station is less than a predetermined distance; A first model building module is used to build a reactive power demand model of the converter station based on the operation control parameters, wherein the reactive power demand model is used to indicate the change of reactive power demand of the converter station when the UHV DC sending-end power grid is in a DC blocking state; A second model building module is used to build a capacity coordination optimization model of the synchronous condenser in the UHV DC sending-end power grid based on the reactive power demand model, wherein the capacity coordination optimization model is used to coordinate the reactive power output of the synchronous condenser in a steady-state or transient operation scenario under the influence of a preset objective function and constraint conditions; A result determination module is used to obtain the capacity optimization result of the synchronous phase condenser based on the capacity coordination optimization model, wherein the capacity optimization result is at least used to indicate the number of static VAR compensation devices put into operation in the UHV DC sending-end power grid under transient operating conditions, and the reactive power output by the synchronous phase condenser.

8. A non-volatile storage medium, characterized in that: The non-volatile storage medium stores a plurality of instructions, and the instructions are suitable for being loaded by a processor and executing the synchronous phase condenser capacity optimization method according to any one of claims 1 to 6.

9. An electronic device, characterized in that: It includes one or more processors and a memory, wherein the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the synchronous phase condenser capacity optimization method described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the synchronous condenser capacity optimization method described in any one of claims 1 to 6 are implemented.

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