387 results about "Automatic voltage control" patented technology

The invention provides an automatic voltage control system of a power plant substation, which comprises a plurality of lower computers, a master upper computer, a standby upper computer, a background computer, a movable communication unit, a power plant decentralized control system (DCS), a plant unit automatic voltage regulator (AVR), a controller area network (CAN), a network communication channel and a power data network, wherein the upper computer and the lower computer intercommunicate in the controller area network (CAN); the upper computer and the background computer communicate through the network communication channel; and the upper computer and the master station communicate in the power data network. The scheme of the invention fully considers the actual field situation of the power plant and has the characteristic of strong applicability.

The invention provides a method used for analyzing the stability of a static voltage; the characteristics of fast calculation speed of a linear simulation method and the accurate calculation of a continuous tide method are utilized and combined by the method, thus being capable of fast and accurately working out the stable margin of the voltage of an electric network under a certain load-increasing mode. The analytical method is suitable not only for the stable off-line analysis of the static voltage, but also for the on-line application of an automatic voltage control system.

The invention discloses a method and device for determining the voltage reactive sensitivity of an automatic voltage control system. The method includes the steps that a power grid is divided into a target area network, a buffering network and an external network, and the state information of the power grid at the current time is collected; according to the state information, equivalence is carried out on the external network through the external network equivalence method reserving the buffering network, and the external network obtained after equivalence, the target area network and the buffering network form a new power grid; the generator node type in the new power grid is adjusted; the voltage reactive sensitivity between PQ nodes in the target area network after the generator node type is adjusted is determined according to a voltage reactive sensitivity matrix between the PQ nodes. The target area network and a key boundary node are taken as analysis objects, and the formed equivalence network can largely reduce external network information, so that the accuracy of the voltage reactive sensitivity is high, time is saved, and efficiency is improved.

The present invention provides a substation voltage control method of realizing comprehensive coordination of continuous equipment and discrete equipment, belonging to power system automatic voltage control technical field. The method includes following steps: collecting the real-time operation data of the substation to be controlled when the control cycle starts; judging each collecting variable based on the preestablished expert rules, calculating the tap joint gear position control variable of the regulating transformer or determining adjustment reactive-load compensation equipment; if is a adjustment reactive-load compensation equipment, the needed reactive-load adjusting variable delta Qg is calculated, the delta Qg processes reactive distribution calculation between a synchronous condenser and a capacitor reactance, the reactive set value of the synchronous condenser and the capacitor reactance sequence needed switch are calculated; the state of the transformer equipment is adjusted according to the obtained reactive set value and the capacitor reactance sequence needed switch and the tap joint gear position control variable of the transformer, realizing ring closed control. The invention improves ability of network bearing accident disturbance, improving the security of the network.

The invention relates to a power network model-based wind power field automatic voltage control method which comprises the following steps of: 1, reading original data and building a wind power field power network mathematical model; 2, reading a wind power field real-time running working condition and a voltage target value released by the power grid dispatching; 3, carrying out load flow calculation to obtain initial load flow distribution on the basis of the former two steps; 4, distributing and releasing the reactive power reference value of a wind driven generator according to a sensitivity ordering strategy; 5, distributing and issuing the reactive power reference value of a dynamic reactive compensation device according to the sequence; and 6, confirming and releasing the tapping point gear reference value of an on-load tap changing transformer according to a step-by step adjustment strategy. According to the power network model-based wind power field automatic voltage control method, the unified coordination control among the reactive power of the wind power field wind driven generator, the reactive power of the dynamic reactive compensation device and the tapping joint of the on load tap changing transformer can be realized.

The invention relates to a wind power plant voltage automatic control method based on a model predictive control theory, and belongs to the technical field of electric power system wind power plant voltage automatic control. The method includes the steps that various current electric quantity measured values of a system are collected and serve as initial values of various electric quantity predicted values, and an optimized control model composed of an optimized objective function and constraint conditions is established according to the predicted values; the optimized control model is simplified, the simplified optimized control model is solved through an optimization tool, and solution sequences of reactive set values of a draught fan and voltage set values of an SVG in an MPC time window are acquired; first values in the solution sequences serve as control objectives and are issued to the draught fan and the SVG respectively, and therefore wind power plant voltages are automatically controlled. The method can be integrated in the automatic voltage control system for wind power plant field operation, and the system can carry out an optimum control strategy in real time according to the power change of a wind power plant.

The invention provides to a prefecture-county integrated automatic voltage control method. The control method comprises the following steps of: obtaining a power grid model, a control model and real-time data required for automatic voltage control; carrying out prefecture and county regional voltage idle work optimization calculation and constructing a control strategy system to obtain the controlling quantity of prefecture and county plant stations; distributing the obtained controlling quantity to a prefecture and county plant stations to be executed in a centralized manner through the prepositive communication of a scheduling automatic system; carrying out regional monitoring and regional management examining statistics; and returning for circulation so as to carry out periodic control monitoring and statistics when the voltage control period is reached. A prefecture-county shared automatic voltage control system more reasonably effectively utilizes various idle work adjustment and voltage control measures in a power grid, the construction investment of the system is reduced, and the system maintenance management is flexible and convenient.

The invention provides a control method for improving reliability of an AVC (Automatic Voltage Control) system of an electric power monitoring center. The control method comprises the steps of performing real-time telemetry data processing; performing real-time remote signaling data processing and dead data processing; and determining the data as dead data, locking a corresponding reactive voltage regulating device and sending alarm signals when the AVC system detects that telemetry information is not refreshed for a long time. The control method for improving the reliability of the AVC system of the electric power monitoring center has the advantages of achieving optimal control and closed loop operation of reactive voltage of the integral grid due to the fact that centralized monitoring, unified management and online control are performed on an on-load voltage regulating device and a reactive compensation device of every power substation in a power grid and ensuring that the AVC system enables a voltage reactive control strategy to be optimized, reducing the times of once action of the reactive voltage regulating device, improving the service life of the device and providing the corresponding technical support for improvement of the reactive voltage management level and safe, stable and high quality operation of the integral power grid due to the fact that the AVC system still relies on real-time data collected through an SCADA (Supervisory Control And Data Acquisition) system to calculate to a great extent.

The invention provides a multilevel joint coordination automatic voltage control method based on decision trees, which relates to the technical field of power system dispatching automation. The method aims to solve the control problem of joint coordination between upper-level and lower-level systems in the same power system, and meanwhile, the decision tree method adopting data mining can also be used to solve the technical problem of the joint coordination between upper-level and lower-level station equipment in the systems of the same level. The method comprises the following implementation processes: 1) performing automatic voltage control AVC construction and practical operation; 2) establishing a data warehouse and node attributes; 3) putting up a decision tree; 4) testing samples; 5) adjusting the node attributes and cutting branches; 6) verifying the samples; and 7) generating a coordination strategy. The data mining method based on decision trees has the characteristics of high intuitionistic property, easy operation and capability of flexibly expanding the node attributes. The method can extract results to be predicted from a great amount of relevant information, which provides bases for power dispatching automatic control decision.

The invention provides a reactive-voltage control method of regional power-grid substations. The reactive-voltage control method comprises the following steps of: acquiring a reactive power instruction issued by an AVC (Automatic Voltage Control) system for each main transformer in all the substations, wherein the reactive power instruction is used for representing the reactive power required to be compensated by each main transformer; monitoring busbar voltage of each substation side; and controlling a dynamic reactive compensation device and a capacitor group to carry out reactive power compensation on respective regional power grids according to monitored conditions of the busbar voltage and the reactive power instruction, wherein the dynamic reactive compensation device and the capacitor group belong to the current substation. The invention also provides a reactive-voltage control system of the regional power-grid substations. The method and the device have the advantages that the coordination work of the dynamic reactive compensation device and the regional AVC system can be realized, the continuous reactive power compensation can be rapidly provided, the control level of the reactive voltage of the substations is greatly improved, the security of a power system is improved and the cost for the reactive power control is reduced.

The present invention provides a coordinated voltage control method based on the coordinating and restricting a real-time updating power plant and substation, belonging to power system automatic voltage control technical field. The invention selects the substation bus as a coordination variable between plants, firstly, each substation is processed with instation automatic voltage control according to the method of ''Nine zone pictures'', and according to the control result, the constraint condition of the coordination variable of the substation is real-time updated by adopting expert rules method; a constraint condition is added to the coordinated secondary voltage control mode of the region to unify solution, reactive power control strategy of the generator is solved. The CSVC mode has no discrete variable, belonging to conventional secondary planning mode, avoiding the resolving of the problem of the complex mixed integer programming, improving the credibility of the real-time control.

The embodiment of the application discloses an AVC (Automatic Voltage Control) system-based reactive voltage optimization method. The method comprises the following steps of: receiving a CIM (Common Information Model) which is derived through an SCADA (Supervisory Control And Data Acquisition) system; receiving input and switching out status information of reactive-load compensation equipment which is derived through a PI (Plant Information System), and reactive-load measurement section real-time data of transformer substations; on the basis of the CIM, optimally calculating the input and switching out status information of the reactive-load compensation equipment and the reactive-load measurement section real-time data through an optimized reactive voltage algorithm, and generating an optimized strategy, wherein the optimized reactive voltage algorithm comprises a primary dual interior point method, a branch-and-bound method and/or a voltage correcting control model method; and the AVC system controls optimization of the voltage according to the optimized strategy. The embodiment of the application further discloses an AVC system-based reactive voltage optimization device. Utilization efficiency of electrical energy can be improved through the embodiment of the application.

The invention discloses a reactive power control method and system for a wind power plant. The method comprises: an AVC (Automatic Voltage Control) substation acquiring target reactive power of the wind power plant, and sending a reactive power adjusting instruction to reactive power compensation equipment according to the target reactive power; the reactive power compensation equipment performing reactive power compensation according to the working mode thereof; and after detecting that the reactive power of the wind power plant reaches the target reactive power, the AVC substation controlling a wind turbine generator in the wind power plant to increase reactive power, so as to replace the reactive power output of the reactive power compensation equipment. The wind turbine generator and the reactive power compensation equipment coordinate to allocate and control the reactive power, and the reactive power compensation equipment is adjusted to preferentially act by sufficiently utilizing and coordinating the reactive power capability of the wind power plant so as to quickly meet the response requirement; and after the voltage of a grid-connected point is stable, the reactive power of the wind turbine generator is increased to replace the reactive power output of the reactive power compensation equipment, thereby providing more surplus capacity for the reactive power compensation equipment and quickly following next reactive power control.

The invention relates to a method for calculating sensitivity of wind power plant reactive power on voltage based on a perturbation method and belongs to the technical field of automatic voltage control of a power system. The method comprises the following steps of: identifying the equivalent impedance of an external power grid accessing to the wind power plant according to the sensitivity of reactive power at a wind power plant grid-connected point on the voltage of the wind power plant through the perturbation method, and forming a complete power network together with a power network in the wind power plant; combining real-time measurement in the wind power plant to form a jacobian matrix, and calculating to obtain the sensitivity matrix of the reactive powers among the nodes in the wind power plant on the voltage; and finally, checking the calculation result by using the obtained sensitivity of the reactive power on the voltage through the perturbation method, if not, identifying the equivalent impedance of the external power grid again, and calculating the sensitivity matrix of the reactive power on the voltage until the sensitivity matrix passes the check. According to the method, the high-accuracy sensitivity matrix of the reactive power on the voltage is obtained finally and is used for voltage control in the wind power plant.

The invention provides a voltage threshold probability-based reactive power optimizing method for a grid containing a wind power plant, which aims to solve the problem that under the condition of wind power networking, the effect of the voltage optimizing control to an automatic voltage control system is not ideal. The method comprises the steps as follows: firstly, collecting grid operation parameters, basic parameters of each wind power generator in the wind power plant, and active power output data of the wind power plant; secondly, acquiring voltage impact factor, power conversion coefficient of the wind power generators and wind power plant active power probability distribution equation through the above parameters, and further obtaining voltage threshold probability; and lastly, establishing a reactive power optimizing model on the basis of the voltage threshold probability, adopting genetic algorithm to solve the model, and obtaining a control instruction of a reactive power device. According to the invention, the voltage threshold probability-based reactive power optimizing method substitutes a conventional reactive power optimizing method for the automatic voltage control system, can enable the voltage optimizing control to the automatic voltage control system to effectively control the reactive power device in the grid under the condition of wind power networking, and ensure the safe and economic operation of the grid.

The invention relates to an ultrahigh voltage power network interconnection line operating state-based voltage control method, which belongs to the technical field of power system automatic voltage control. The method comprises the following steps of: detecting the commissioning state of an ultrahigh voltage interconnection line; if the ultrahigh voltage interconnection line is not put into operation, performing secondary voltage control according to the default voltage limit; if the ultrahigh voltage interconnection line is put into operation, when the ultrahigh voltage power network interconnection line is at a certain state space, automatically generating a set of voltage limit values of an ultrahigh voltage control bus by using an ultrahigh voltage system; if the state space, where the ultrahigh voltage power network interconnection line is, does not change, not changing the voltage limit values of the ultrahigh voltage control bus; and if the operating state of the ultrahigh voltage power network interconnection line moves to a new state space and an ultrahigh voltage control system detects the change, automatically generating a new voltage limit value of the ultrahigh voltage control bus by using the ultrahigh voltage control system. In the method, a secondary voltage control method in the conventional AVC system is improved, so that the aims of safe and stable operation and economic control of power network equipment are fulfilled.

The invention relates to a grid-connected wind power plant point voltage control method based on MCR (Magnetic Control Reactor) and capacitance mixed compensation. The method comprises the steps of collecting real-time data of a grid-connected wind power plant region, and receiving a voltage instruction issued by a superior AVC (Automatic Voltage Control); judging whether the grid-connected wind power plant point voltage meets a requirement, if not, taking the smallest grid-connected point voltage deviation and the smallest input of reactive-load compensation equipment as targets, calling a multi-target evolutionary particle swarm optimization to solve the current input reactive compensation, obtaining the final switching amount of each equipment according to a capacitance and MCR mixed compensation strategy, and issuing the same to finally realize the effect that the grid-connected wind power plant point voltage quality is kept at a higher level. The needed switching amount of each equipment can be accurately solved by the multi-objective optimization model and a static and dynamic reactive-load compensation equipment mixed compensation strategy, and the aims of rapidly responding to the instruction issued by the superior, stabilizing the grid-connected wind power plant point voltage and improving electric energy quality are achieved.

The invention discloses an electric power telemechanical apparatus RTU and a method for realizing the automatic voltage control of the power plant. The inventive electric power telemechanical apparatus includes a central control module, a remote signalling module, a telemetering module, a remote regulating module and a remote control module, wherein the central control module includes a communication submodule, a data bank submodule and an automatic voltage control submodule, which generates the control signal for adjusting the wattless production output of the generating set, based on the data stored in the data bank submodule, and transmits the control signals to the remote regulating module or the remote control module through the communication submodule, then transmits to the generating set which participates in the voltage control through the remote regulating module or the remote control module, realizes the automatic voltage control. The invention gives full play to the function of the electric power telemechanical apparatus, reduces the amount of the situ hardware units, increases the operational precision of the data in the AVC adjusting process.

The invention discloses a power station voltage reactive power master-slave double-command control method, comprising the following steps: 1) master station AVC (automatic voltage control) scans power grid running status data acquired by SCADA (supervisory control and data acquisition) in real time; 2) the master station AVC makes a running working condition decision and automatically selects power plants and buses participating in calculation and control; 3) area voltage is refreshed to control a quadratic programming model; 4) solving is carried out by a quadratic programming algorithm, themaster station AVC sends a double-command control strategy for the power plants through an SCADA telecontrol channel, a main command controls a target for high-voltage bus voltages of all sections, and an auxiliary command controls total upper/lower limit for the reactive power of a hanging unit; and 5) power plant sub-station AVC responds the control strategy sent by the master station through the double commands, and while a voltage command is tracked and a reactive power limit value restraining condition is met, reactive power coordination control in an execution link can be realized. In the method, the target/restraining of a master station AVC calculating link and a sub-station AVC execution link are realized to be consistent, so that the unit reactive power with rapid adjusting speed can be restrained in the practical running process, therefore, the reactive power coordination control in an execution link can be ensured.

The invention discloses a method for an AVC (Automatic Voltage Control) system to verify power network global optimal control parameters. the optimal control parameter group and the optimal reactive power flow distribution are verified by being based on EMS (Energy Management System) real time data and the power network state estimation, and based on a uniform typical, substituting load daily historical data, and comparing the pivot node voltage regulation speed rates, the voltage control quality rates and the power network loss values respectively. By adopting the method disclosed by the invention, the problem in the prior art that the AVC substation parameters can not be verified to be optimum in the power network is solved, thus the method provides conditions for achieving the final goal of qualified node voltage in the power network and minimized network loss; and the method also can be used for verifying the optimal reactive power flow distribution, and provides aided decision evidences for investing in the power network construction.

The invention relates to a phase-camera-based multi-target reactive voltage coordination control method and system. The method comprises: power flow data and a stable data model of access to an alternating-current grid by a phase camera are established; fault checking is carried out on stability of a phase camera near-region main grid voltage by using an alternating-current/direct-current system;when instability of the phase camera near-region main grid voltage is determined, the machine-side voltage is controlled by subtranient and transient automatic responses of the phase camera body and access of the phase camera to the high-voltage bus voltage is recovered; whether the near region of the phase camera has low voltage suspension is determined and a determination result is obtained; when the determination result indicates the low voltage suspension in the near region of the phase camera, the short-circuit current of the main gird in the near region of the phase camera is calculatedand the reactive power demand capacity of the voltage control of the grid is determined; the system voltage is restored quickly by employing the reactive power control measures of increasing the reactive output of the phase camera in turn and the near-region low-voltage capacitance of switching in turn; and with the automatic voltage control system, the reactive power distribution of the power grid in the near region of the phase camera is adjusted and the dynamic reactive adjusting capability of the phase camera is restored.

The invention discloses a UHVDC near zone multi-level grid coordinated automatic voltage control method and a UHVDC near zone multi-level grid coordinated automatic voltage control system. The UHVDC near zone multi-level grid coordinated automatic voltage control method has the beneficial effects of classifying a UHV converter station, a 500/750 kV transformer substation electrically and closely connected with the UHV converter station, and a power plant connected between the converter station and the transformer substation as reactive power resources in a UHVDC near zone grid overall plan region, performing multi-level grid coordinated automatic voltage control according to a fixed cycle, making overall plans for, coordinating and controlling different types of reactive power resources including a phase modifier and the like in the UHV converter station and belonging to power grids of different levels originally, and making overall plans for, coordinating and controlling different types of reactive power resources belonging to a provincial power grid. The UHVDC near zone multi-level grid coordinated automatic voltage control method and the UHVDC near zone multi-level grid coordinated automatic voltage control system solve the problem that the reactive power resources of the UHV converter station cannot effectively participate in AVC control of the power grid, reduce the complexity of UHVDC near zone multi-level grid coordinated control, and realize the AVC control with various types of coordinated reactive power resources including the phase modifier.

The invention discloses a power grid automatic voltage control method and system taking global optimum as a target. The method comprises the steps of obtaining a real-time state evaluation result of the power grid according to calculation cycles, if the state evaluation result is converged and telemetering percent of pass is greater than or equal to a threshold value, calculating and obtaining a state expectation value of each reactive voltage source based on a global optimization method, or otherwise, if the bus voltage exceeds standard, assigning the state expectation value of each disperse and adjustable reactive voltage source with the value of the last calculation cycle separately, and calculating and obtaining the state expectation value of each continuous and adjustable reactive voltage source; if the bus voltage dose not exceed standard, assigning the state expectation value of each reactive voltage source with the value of the last calculation cycle separately; finally issuing and executing the corresponding state expectation values; and the system comprises respective units corresponding to the steps in the abovementioned method. According to the method and the system, power grid partitioning is not needed, the voltage requirement of each bus of the power grid can be satisfied while the global reactive power flow optimum is taken as the control target, so that the network loss can be further lowered, and the power grid global optimal economic operation can be realized.

The invention relates to the technical field of automatic voltage control of power systems, in particular to a method for designing coordinate amount among automatic voltage control systems of a power grid and an implementing method thereof. The coordinate amount represents the voltage areal control deviation and consists of boundary node voltages among the automatic voltage control systems in different area and on different levels and weighted sum of reactive disturbance injected into a local area from foreign areas. In the invention, whether reactive disturbance occurs in or out the area can be determined through the coordinate amount, the direction and size of the reactive influences on neighboring areas of the control action of the local area are measured, each control area only responds for the reactive disturbance in the local area, and the examination is fair; and thus, the areal control responsibility is clear, coupling is reduced and coordinate control can be realized.

The invention discloses an AVC (Automatic Voltage Control) joint-debugging control method based on the var compensation technology, which comprises the following steps of: installing and configuring a static var compensator (SVC) in a power grid; obtaining the real-time information of the SVC by a control system for the AVC; according to an SVC parameter model and constant value information in the AVC joint-debugging system, carrying out voltage reactive power optimization joint-debugging strategy calculation by combining with the voltage reactive power real-time information; and regulating the SVC and other SVCs with the fixed volume in the power grid. According to the AVC joint-debugging control method, the SVC in the station and the original static reactive power compensation equipment can be controlled in a coordination mode.