CN112560227B - A method for simulation preview of power grid dispatching day-ahead planning - Google Patents

Abstract

The invention relates to a power grid dispatching day-ahead plan simulation rehearsal method, which comprises the following steps of 1) generating a power generation curve, a load curve and a maintenance operation event table for power grid simulation; generating a power grid simulation expected fault event table; generating a day-ahead plan simulation teaching plan; 2) starting a power grid training simulation system according to the day-ahead plan simulation teaching plan, setting power grid operation mode changes according to a power grid simulation overhaul operation event table, and completing simulation load flow calculation according to power grid power generation and load values set by a power grid simulation unit output table and a power grid simulation load tidal current table; triggering simulation faults according to a power grid simulation expected fault event table, simulating the power grid fault condition, and completing simulation load flow calculation after fault setting; 3) and saving the simulation power flow sections according to a set period, and calling power flow calculation and N-1 scanning functions to give the power grid operation risk of each simulation preview section. The invention improves the safety of scheduling operation.

Description

A method for simulation preview of power grid scheduling day-ahead planning

technical field

The invention belongs to the field of power system dispatch automation, and in particular relates to a method for simulation and rehearsal of a day-ahead scheduling plan of a power grid.

Background technique

The dispatch of my country's power system usually requires the formulation of a day-ahead dispatch plan, including a day-ahead power generation plan and a maintenance plan. In real-time operation, the normal operation of the grid is guaranteed by executing the day-ahead plan. The power grid security check and other work have been completed in the process of formulating the previous plan, but it lacks the simulation and rehearsal function of the power grid dispatching plan, so it is impossible to simulate the sudden failure of the power grid during the execution of the daily dispatch plan, and identify the possible operation risks. . The power grid training simulation system (DTS) has been widely used in the daily training and exercise of dispatching operators. How to apply the power grid training simulation system (DTS) to the simulation rehearsal of the dispatch plan a few days ago, and to simulate the emergency state of the power grid, prompting the risk of power grid operation has become an urgent problem to be solved in the dispatch simulation of interconnected large power grids.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a method for the simulation and preview of the grid scheduling day-ahead plan, which improves the security of the scheduling operation.

To achieve the above object, the technical scheme of the present invention comprises the following steps:

It includes the following steps,

1) Generate power generation curve, load curve and maintenance operation event table for power grid simulation; generate power grid simulation expected fault event table; generate a day-ahead planning simulation lesson plan;

2) Start the power grid training simulation system according to the previously planned simulation teaching plan, set the power grid operation mode change according to the power grid simulation maintenance operation event table, and complete the simulated power flow according to the power grid generation and load values set by the power grid simulation unit output table and the power grid simulation load flow table. Calculation; trigger simulation faults according to the power grid simulation expected fault event table, simulate power grid fault conditions, and complete the simulation power flow calculation after fault setting;

3) Save the simulated power flow section according to the set period, and call the power flow calculation and N-1 scanning functions to give the power grid operation risk of each simulated power flow section.

Further, in step 1), according to the initial power grid operation section, according to the power generation plan, the maintenance plan and the load forecast data before the grid dispatching, the power generation curve, the load curve and the maintenance operation event table for power grid simulation are generated; Anticipate the accident, set the predicted fault type and time of the power grid simulation, and generate the power grid simulation predicted fault event table.

Further, in step 1), the acquisition method of the power generation plan, maintenance plan and load forecast data before the grid dispatching is: obtaining the grid dispatching power generation plan, maintenance plan and load forecast data before the grid dispatching automation system;

The day-ahead power generation plan includes a 96-point active power plan for all generating units in the power grid;

The maintenance plan includes the time plan of the switch knife action;

The load forecast data includes 96-point active power forecast data of all busbar loads in the power grid.

Further, in step 1), the power generation curve and the load curve are generated by generating a power grid simulation section at a certain time.

Further, the generation method of the power grid simulation section at a certain moment is to obtain plan data with a period of 15 minutes one by one according to the initial power grid operation section, and generate the power grid simulation power flow section at that moment.

Further, the generation of the power grid simulation section at a certain moment includes the following steps:

S1: Based on the initial power grid operation section, set the active power of all units to the planned active power value at this moment, and set the active power of all loads to the active power prediction value of this moment; call the power flow calculation program to complete the power flow calculation of the planned section at this moment, Thereby, the active value of the output current can be obtained;

S2: Calculate the deviation P _w-acc between the output power flow active power value of the internal grid unit in the planned section and the planned active power value. The calculation process of P _w-acc is shown in formula (1):

Among them, UP _k represents the planned active power value of the k-th internal grid generator equipment in the planned section; UL _k represents the tidal active power value of the k-th internal grid generator equipment in the planned section; n represents all internal grid power generation in the planned section The number of generators and equipment; the internal network generator equipment refers to the generator set directly controlled by the control center;

S3: Calculate the active power correction value ΔP _net-i of the output of each external grid unit in the planned section, ΔP _net-i is shown in formula (2):

Among them, SP _i represents the unit capacity value of the ith external grid generator equipment in the planned section; m represents the number of all external grid generator equipment in the planned section, SP _t represents the t external grid generator equipment in the planned section The generator capacity value of the external grid refers to the generator set or equivalent unit model that is not directly controlled by the control center.

S4: Set the active power output of each external grid generator in the planned section to increase ΔP _net-i ; set all internal grid units to be non-adjustable, and all external grid units to be adjustable; call the power flow calculation program again to complete the moment The power flow calculation of the planned section; after the power flow calculation is completed, all the internal grid units are set to be adjustable; through the above steps, the deviation correction between the grid generation active power plan and the load forecast is realized, and the accurate power flow result at the moment is obtained;

S5 writes the unit power flow value in the power flow calculation result at the moment into the power grid simulation unit output table at the corresponding moment, and writes the load flow value into the power grid simulation load flow table at the corresponding moment.

Further, the acquisition method of the maintenance operation event table is: according to the time plan of the switch knife switch action in the maintenance plan, the switch knife switch displacement event in the simulation section is set, and the displacement event is written in the power grid simulation maintenance operation event table. ; The switch knife switch displacement event includes opening and closing information and displacement time.

Further, the switch knife switch displacement event includes opening and closing information and displacement time.

Further, in step 1), the 96-point power grid simulation unit output table, the 96-point power grid simulation load flow table, the power grid simulation maintenance operation event table and the power grid simulation expected fault event table are saved as the previously planned power grid simulation lesson plan.

Further, step 3) comprises the following steps:

3-1) Calculate the overloaded equipment and heavy-duty equipment of each simulated power flow section through the power flow calculation; count the overloaded equipment and heavy-loaded equipment in all simulated pre-review sections, and give the sorting results according to the number of equipment statistics; The device indicates that the risk of heavy overloading of the device is greater;

3-2) Through the power grid N-1 scanning function, the N-1 overloaded equipment and heavy-duty equipment of each simulation preview section are given; the overloaded equipment and heavy-loaded equipment calculated by N-1 in all simulated power flow sections are counted, according to the equipment statistics The number of times gives the sorting result; the device with more counts means the greater the risk of heavy overload calculated by device N-1.

The positive effects of the present invention are as follows:

1. The present invention makes full use of the power grid dispatching day-ahead power generation plan, maintenance plan and load forecast data to generate a power grid simulation teaching plan, which improves the accuracy of the day-ahead planning simulation power flow calculation.

2. The method of the present invention accurately simulates the power flow distribution of the power grid under the expected fault by simulating the power grid plan ahead of the day and the predicted fault, further clarifies the weak link of the power grid plan execution, and improves the security of dispatching operation.

Description of drawings

Figure 1 is a flow chart of the present invention.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, its application, or uses. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application. It includes the following steps,

1) Generate power generation curve, load curve and maintenance operation event table for power grid simulation; generate power grid simulation expected fault event table;

In step 1), according to the initial power grid operation section, according to the power generation plan, maintenance plan and load forecast data before the grid dispatching, the generation curve, load curve and maintenance operation event table for power grid simulation are generated; according to the expected accident set by the user, Set the expected fault type and time of power grid simulation, and generate a grid simulation expected fault event table.

In step 1), the method of obtaining the power generation plan, maintenance plan and load forecast data before the grid dispatching day is: obtaining the power grid dispatching day power generation plan, the maintenance plan and the load forecast data from the grid dispatching automation system;

The day-ahead power generation plan includes a 96-point active power plan for all generating units in the power grid;

The maintenance plan includes the time plan of the switch knife action;

The load forecast data includes 96-point active power forecast data of all busbar loads in the power grid.

In step 1), the power generation curve and the load curve are generated by generating a power grid simulation section at a certain time.

The generation method of the power grid simulation section at a certain moment is to obtain the planned data with a period of 15 minutes one by one according to the initial power grid operation section, and generate the power grid simulation power flow section at that moment.

The generation of the power grid simulation section at a certain time includes the following steps:

S1: Based on the initial power grid operation section, set the active power of all units to the planned active power value at this moment, and set the active power of all loads to the active power prediction value of this moment; call the power flow calculation program to complete the power flow calculation of the planned section at this moment, Thereby, the active value of the output current can be obtained;

S2: Calculate the deviation P _w-acc between the output power flow active power value of the internal grid unit in the planned section and the planned active power value. The calculation process of P _w-acc is shown in formula (1):

Among them, UP _k represents the planned active power value of the k-th internal grid generator equipment in the planned section; UL _k represents the tidal active power value of the k-th internal grid generator equipment in the planned section; n represents all internal grid power generation in the planned section The number of generators and equipment; the internal network generator equipment refers to the generator set directly controlled by the control center;

S3: Calculate the active power correction value ΔP _net-i of the output of each external grid unit in the planned section, ΔP _net-i is shown in formula (2):

Among them, SP _i represents the unit capacity value of the ith external grid generator equipment in the planned section; m represents the number of all external grid generator equipment in the planned section, SP _t represents the t external grid generator equipment in the planned section The generator capacity value of the external grid refers to the generator set or equivalent unit model that is not directly controlled by the control center.

S4: Set the active power output of each external grid generator in the planned section to increase ΔP _net-i ; set all internal grid units to be non-adjustable, and all external grid units to be adjustable; call the power flow calculation program again to complete the moment The power flow calculation of the planned section; after the power flow calculation is completed, all the internal grid units are set to be adjustable; through the above steps, the deviation correction between the grid generation active power plan and the load forecast is realized, and the accurate power flow result at the moment is obtained;

S5 writes the unit power flow value in the power flow calculation result at the moment into the power grid simulation unit output table at the corresponding moment, and writes the load flow value into the power grid simulation load flow table at the corresponding moment.

The acquisition method of the maintenance operation event table is: according to the time plan of the switch knife switch action in the maintenance plan, set the switch knife switch displacement event in the simulation section, and write the displacement event into the power grid simulation maintenance operation event table; The switch knife switch displacement event includes the opening and closing information and the displacement time.

The switch knife switch displacement event includes opening and closing information and displacement time.

In step 1), the 96-point power grid simulation unit output table, the 96-point power grid simulation load flow table, the power grid simulation maintenance operation event table and the power grid simulation expected fault event table are saved as the previously planned power grid simulation lesson plan.

The structure of the power grid simulation unit output table is shown in Table 1 below:

Table 1

Field Name Field Description Genset name device name, 64-byte string The name of the power plant Factory station name, 64-byte string 96-point unit active The active power output of the unit, an array of 96-point floating-point numbers 96 point unit reactive power Unit reactive power output, 96-point floating point array 96-point generator terminal voltage Unit terminal voltage per unit value, 96-point floating point number array

The structure of the power grid simulation load flow table is shown in Table 2 below:

Table 2

Field Name Field Description Load equipment name device name, 64-byte string Substation name Factory station name, 64-byte string 96 load active power Load active value, array of 96-point floating point numbers 96 load reactive power Load reactive power value, array of 96-point floating point numbers

The structure of the power grid simulation maintenance operation event table is shown in Table 3 below:

table 3

The structure of the power grid simulation expected fault event table is shown in Table 4 below:

Table 4

Field Name Field Description device name device name, 64-byte string Factory name Factory station name, 64-byte string Fault type Integer, device operation type enumeration value fault integer data Fault data value, 32-point integer array fault floating point data Fault data value, 32-point float array downtime Time stamp, equipment expected failure time

2) Start the power grid training simulation system according to the previously planned simulation teaching plan, set the power grid operation mode change according to the power grid simulation maintenance operation event table, and complete the simulated power flow according to the power grid generation and load values set by the power grid simulation unit output table and the power grid simulation load flow table. Calculation; trigger simulation faults according to the power grid simulation expected fault event table, simulate power grid fault conditions, and complete the simulation power flow calculation after fault setting;

3) Save the simulated power flow section according to the set period, and call the power flow calculation and N-1 scanning functions to give the power grid operation risk of each simulated power flow section.

Step 3) includes the following steps:

3-1) Calculate the overloaded equipment and heavy-loaded equipment of each simulated power flow section through the power flow calculation; count the overloaded equipment and heavy-loaded equipment in all simulation preview sections, and give the sorting results according to the number of equipment statistics; The device indicates that the risk of heavy overloading of the device is greater;

3-2) Through the power grid N-1 scanning function, the N-1 overloaded equipment and heavy-duty equipment of each simulation preview section are given; the overloaded equipment and heavy-loaded equipment calculated by N-1 in all simulated power flow sections are counted, according to the equipment statistics The number of times gives the sorting result; the device with more counts means the greater the risk of heavy overload calculated by device N-1.

According to the initial power grid operation section, according to the power generation plan, maintenance plan and load forecast data before the grid dispatching day, the invention generates the power generation curve, load curve and maintenance operation event table required for power grid simulation; according to the expected accident set by the user, the power grid is set The predicted fault type and time of the simulation are generated, and the power grid simulation predicted fault event table is generated; the 96-point power grid simulation unit output table, the 96-point power grid simulation load flow table, the power grid simulation maintenance operation event table and the power grid simulation expected fault event table are saved as the plan for the day before Power grid simulation lesson plan. Start the power grid training simulation system with the previously planned simulation lesson plan, set the power grid operation mode change according to the power grid simulation maintenance operation event table, and complete the simulation power flow calculation according to the power generation and load values set by the power grid simulation unit output table and the power grid simulation load flow table; The simulation expected fault event table triggers the simulation fault, simulates the grid fault condition, and completes the simulation power flow calculation after the fault setting. The simulation power flow section is saved according to the set period, and the power flow calculation and N-1 scanning functions are called to give the power grid operation risk of each simulation preview section. The invention makes full use of the power grid dispatching day-ahead power generation plan, maintenance plan and load forecast data to generate a power grid simulation teaching plan, which improves the accuracy of the day-ahead planning simulation power flow calculation; and accurately simulates the power grid under the expected fault by simulating the power grid's day-ahead plan and expected faults The distribution of power flow further clarifies the weak links in the implementation of the power grid plan, and improves the safety level of dispatching operation.

The present invention proposes a simulation preview method for grid dispatching day-ahead planning. The method realizes the simulation rehearsal of the day-ahead dispatching plan of the power grid, accurately simulates the operation state of the power grid that is executed by the day-ahead plan, improves the risk prediction and identification ability of large-scale interconnected power grids, and enhances the level of safe and economic operation of the power grid.

The process of the present invention is explained by summarizing the steps of the present invention and selecting keywords to assist in explaining the process of the present invention. Specifically, as shown in FIG. 1 , firstly obtain the initial operation section and the previous plan data, then generate a simulation teaching plan according to the plan data, and drive the simulation system to run, Automatically execute the event table, periodically save the simulation section after the simulation power grid event is executed, and finally perform an N-1 scan to clarify the operation risk of the simulation section.

The present invention proposes a simulation preview method for grid dispatching day-ahead plan, which has the following advantages:

1. The present invention proposes a power grid scheduling simulation preview method, which makes full use of the power grid scheduling day-ahead power generation plan, maintenance plan and load forecast data to generate a power grid simulation lesson plan, which improves the accuracy of the day-ahead planning simulation power flow calculation.

2. The method of the present invention accurately simulates the power flow distribution of the power grid under the expected fault by simulating the power grid plan ahead of the day and the predicted fault, further clarifies the weak link of the power grid plan execution, and improves the security of dispatching operation.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, operations, devices, components and/or combinations thereof.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise. Meanwhile, it should be understood that, for the convenience of description, the dimensions of various parts shown in the accompanying drawings are not drawn in an actual proportional relationship. Techniques, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the authorized description. In all examples shown and discussed herein, any specific value should be construed as illustrative only and not as limiting. Accordingly, other examples of exemplary embodiments may have different values. It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further discussion in subsequent figures.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (6)

1. A power grid dispatching day-ahead plan simulation rehearsal method is characterized in that: which comprises the following steps of,

1) generating a power generation curve, a load curve and a maintenance operation event table for power grid simulation; generating a power grid simulation expected fault event table; generating a day-ahead plan simulation teaching plan;

2) starting a power grid training simulation system according to the day-ahead plan simulation teaching plan, setting power grid operation mode changes according to a power grid simulation overhaul operation event table, and completing simulation load flow calculation according to power grid power generation and load values set by a power grid simulation unit output table and a power grid simulation load tidal current table; triggering a simulation fault according to a power grid simulation expected fault event table, simulating a power grid fault condition, and completing simulation load flow calculation after fault setting;

3) saving the simulation power flow sections according to a set period, and calling a power grid power flow calculation and N-1 scanning function to give a power grid operation risk of each simulation power flow section;

in the step 1), generating a power generation curve, a load curve and a maintenance operation event table for power grid simulation according to an initial power grid operation section and power grid dispatching day-ahead power generation plan, maintenance plan and load prediction data; setting the expected fault type and time of power grid simulation according to the expected accident set by a user, and generating a power grid simulation expected fault event table;

in the step 1), generating the power generation curve and the load curve by generating a power grid simulation section at a certain moment;

the generation mode of the power grid simulation section at a certain moment is to acquire plan data with a period of 15 minutes one by one according to the initial power grid operation section and generate the power grid simulation tide section at the moment;

the generation of the simulation section of the power grid at a certain moment comprises the following steps,

s1: on the basis of the initial power grid operation section, setting the active power of all the units as a planned active power value at the moment, and setting the active power of all the loads as an active power predicted value at the moment; calling a power flow calculation program to complete power flow calculation of the planned section at the moment so as to obtain an output power flow active value;

s2: calculating the deviation P between the output power flow active value and the planned active value of the intranet unit in the planned section_w-acc，P_w-accThe calculation process of (2) is shown in formula (1):

wherein, UP_kA planned active value representing the kth intranet generator equipment of the planned section; UL (UL)_kThe current active value of the kth intranet generator equipment of the planned section is represented; n represents the number of all internal network generator devices in the planned section; the intranet generator equipment is a generator set directly controlled by a control center;

s3: calculating the active power correction value delta P of the output of each external network unit in the planned section_net-i，ΔP_net-iAs shown in formula (2):

wherein, SP_iShowing the planned cross sectionThe unit capacity values of the i external network generator devices; m represents the number of all external network generator devices in the planned section, SP_tThe unit capacity value of the t-th external network generator equipment of the planned section is represented; the external network generator equipment refers to a generator set or an equivalent generator set model which is not directly controlled by a control center;

s4: the active power output increase delta P of each external network generator for setting the planned section_net-i(ii) a All internal network units are set to be unadjustable, and all external network units are set to be adjustable; calling a load flow calculation program again to complete the load flow calculation of the planned section at the moment; after the load flow calculation is completed, setting all the intranet units to be adjustable; through the steps, the deviation correction between the power generation active plan of the power grid and the load prediction is realized, and the accurate tidal current result at the moment is obtained;

and S5, writing the unit load flow value in the current calculation result at the moment into the power grid simulation unit output table at the corresponding moment, and writing the load flow value into the power grid simulation load current table at the corresponding moment.

2. The power grid dispatching day-ahead plan simulation rehearsal method according to claim 1, characterized in that: in the step 1), the power generation plan, the overhaul plan and the load prediction data before the power grid dispatching day are obtained in the following modes: acquiring a power generation plan, a maintenance plan and load prediction data of a power grid dispatching day ahead from a power grid dispatching automation system;

the day-ahead power generation plan comprises 96 active plans of all generator sets in the power grid;

the maintenance plan comprises a time plan for switching on and off the disconnecting link;

the load prediction data comprises 96-point active prediction data of all bus loads in the power grid.

3. The power grid dispatching day-ahead plan simulation rehearsal method according to claim 1, characterized in that: the method for acquiring the maintenance operation event list comprises the following steps: setting a switch disconnecting link displacement event in the simulation section according to a time plan of switch disconnecting link action in the maintenance plan, and writing the displacement event into a power grid simulation maintenance operation event table; the switch disconnecting link displacement event comprises switching-on and switching-off information and displacement time.

4. The power grid dispatching day-ahead plan simulation rehearsal method according to claim 3, characterized in that: the switch disconnecting link displacement event comprises switching-on and switching-off information and displacement time.

5. The power grid dispatching day-ahead plan simulation rehearsal method according to claim 1, characterized in that: in the step 1), a 96-point power grid simulation unit output table, a 96-point power grid simulation load tidal current table, a power grid simulation overhaul operation event table and a power grid simulation expected fault event table are stored as a planned power grid simulation teaching plan in the day-ahead.

6. The power grid dispatching day-ahead plan simulation rehearsal method according to claim 1, characterized in that: the step 3) comprises the following steps:

3-1) calculating and providing overload equipment and overload equipment of each simulation load flow section through the power grid load flow; counting overload devices and heavy-load devices in all simulation preview sections, and giving a sequencing result according to the device counting times; the more the statistics times, the larger the equipment overload risk;

3-2) providing N-1 overload equipment and heavy-load equipment of each simulation preview section through the power grid N-1 scanning function; counting overload devices and overload devices calculated by N-1 in all simulation power flow sections, and giving a sequencing result according to the counting times of the devices; a device with a higher number of statistics indicates a higher risk of heavy overload calculated by the device N-1.

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