CN111952979A

CN111952979A - Control method and control system for power utilization load in substation

Info

Publication number: CN111952979A
Application number: CN202010778130.3A
Authority: CN
Inventors: 秦立斌; 吴国锋; 包新宇; 黎锦洪
Original assignee: Guangdong Power Grid Co Ltd; Dongguan Power Supply Bureau of Guangdong Power Grid Co Ltd
Current assignee: Guangdong Power Grid Co Ltd; Dongguan Power Supply Bureau of Guangdong Power Grid Co Ltd
Priority date: 2020-08-05
Filing date: 2020-08-05
Publication date: 2020-11-17
Anticipated expiration: 2040-08-05
Also published as: CN111952979B

Abstract

The invention belongs to the technical field of equipment load control in a transformer substation, and discloses a method for controlling power utilization load in the transformer substation, which comprises the following steps: dividing the load of the electric equipment into a plurality of classes according to the importance degree; presetting a capacity margin range; obtaining the power shortage according to the difference value between the current electric load of the electric equipment and the current generating capacity of the current generating device; when the power utilization shortage is larger than the maximum capacity margin value of the capacity margin range, cutting off the load according to the power utilization shortage and the importance degree of the load; and when the power utilization shortage is smaller than the minimum capacity margin value of the capacity margin range, the load is increased according to the power utilization shortage and the importance degree of the load. According to the control system provided by the invention, the electric load in the substation is removed or added by adopting the method, so that the working efficiency of the load in the substation is improved.

Description

Control method and control system for power utilization load in substation

Technical Field

The invention relates to the technical field of load control of equipment in a transformer substation, in particular to a method and a system for controlling power utilization load in the transformer substation.

Background

The transformer substation comprises primary equipment and secondary equipment, wherein the primary equipment comprises a transformer, a high-voltage circuit breaker, a disconnecting switch, a bus, a lightning arrester, a capacitor, a reactor and the like, and the secondary equipment comprises a relay protection device, a monitoring device, a metering device, a direct current device for providing a power supply and the like.

In a substation, secondary devices are interconnected to form an electrical circuit that monitors, controls, regulates, and protects the primary devices, referred to as a secondary circuit. Failure of the secondary circuit often disrupts and affects the normal operation of the power production transport. Therefore, the secondary circuit, although not the subject of power generation, plays an important role in protecting the safety of power generation and supplying qualified electric energy to users. The secondary circuit is also provided with a load applied to lighting observation, such load needs to be frequently turned on or off, which affects the operation of the secondary circuit and even causes a fault in a special case, so that the electric load in the secondary circuit needs to be controlled in real time.

Disclosure of Invention

One object of the present invention is: the method for controlling the power utilization load in the substation improves the working efficiency of the load by orderly cutting off or adding the power utilization load in the substation. Another object of the invention is: the control method is adopted for control, and the working efficiency of the power utilization load in the substation is improved.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method for controlling power utilization load in a substation station comprises the following steps:

dividing the load of the electric equipment into a plurality of classes according to the importance degree;

presetting a capacity margin range;

obtaining the power shortage according to the difference value between the current electric load of the electric equipment and the current generating capacity of the current generating device;

when the power utilization shortage is larger than the maximum capacity margin value of the capacity margin range, cutting off the load according to the power utilization shortage and the importance degree of the load; and when the power utilization shortage is smaller than the minimum capacity margin value of the capacity margin range, the load is increased according to the power utilization shortage and the importance degree of the load.

As an optional technical scheme, the method comprises the following steps: the load of the electric equipment is divided into a plurality of types according to the importance degree, and the method specifically comprises the following steps:

dividing the loads of the electric equipment group into I type loads, II type loads and III type loads according to the importance degree of the use purpose; wherein

The type I load is a load which can affect the safety of a human body or equipment due to short-time power failure and cause the production operation to be stopped or the load of a main transformer to be reduced;

the class II load is a load which allows short-time power failure, but has long power failure time and possibly influences normal production operation;

the class III load is a load which cannot influence production operation due to long-time power failure.

As an optional technical scheme, the method comprises the following steps: the method for cutting off or adding the load specifically comprises the following steps:

in the process of cutting off the load, sequentially cutting off the load from a class III load to a class II load according to the importance degree of the load;

in the process of increasing the load, the loads are increased in sequence from the class II load to the class III load according to the importance degree of the load.

As an optional technical scheme, when selectively cutting off loads of the same level of importance, the load with the least number of feeders in the currently used loads is cut off; and/or

When loads with the same level of importance are added, the load with the largest number of feeders in the currently unused loads is added.

As an optional technical solution, when selectively cutting off the load with the same level of importance, the load with the largest electric power in the currently used loads is cut off; and/or

When loads with the same level of importance are added, the load with the lowest electric power in the currently unused load is added.

As an optional technical scheme, when the power shortage is greater than the maximum capacity margin value of the capacity margin range, whether the number of the power generation devices currently used is smaller than the number of the power generation devices in the substation and the currently used loads are all class I loads is judged, if yes, the number of the power generation devices connected with the power equipment is increased, the power shortage is recalculated, and if not, the loads are cut.

As an optional technical solution, in the process of adding the load, if all the class I loads and class II loads in the substation are in the use state, it is determined whether to add the class III load according to the current lighting environment of the substation, and if the current lighting environment is a dark environment, the class III load is added.

As an optional technical solution, before calculating the power shortage, acquiring a load connection condition between a power generation device and the power consumption equipment:

when at least two power generation devices are used currently and the at least two power generation devices are respectively connected with loads with different importance degrees according to the power generation stability degrees, the difference value between the sum of the current electrical load and the capacity margin of the electrical equipment connected with the same power generation device and the current electrical capacity of the corresponding power generation device is independently judged, and the corresponding electricity utilization shortage of each power generation device is obtained;

and when at least two power generation devices are used currently and each power generation device is connected with loads with different importance degrees, obtaining the power utilization shortage according to the sum of the current power load of the power utilization equipment and the capacity margin and the difference of the current capacity sum of all the power generation devices.

As an optional technical scheme, the method comprises the following steps: after the load is cut off or added, the method also comprises the following steps: checking the capacity load rate of the power generation device which operates currently;

when the capacity load rate is within a preset range, all the power generation devices which are operated at present continuously work;

when the capacity load rate is lower than the minimum preset value, reducing the operation number of the power generation devices;

and when the capacity load rate is higher than the highest preset value, increasing the operation number of the power generation devices.

A control system is controlled by adopting the control method.

The invention has the beneficial effects that:

the invention provides a method for controlling power utilization loads in a substation, which comprises the steps of dividing the loads of power utilization equipment into a plurality of classes according to the importance degree, presetting a capacity margin range, obtaining the power utilization shortage according to the difference value between the current power load of the power utilization equipment and the current generating capacity of a current generating device, and cutting off the loads according to the power utilization shortage and the importance degree of the loads when the power utilization shortage is greater than the maximum capacity margin value of the capacity margin range; when the power utilization shortage is smaller than the minimum capacity margin value of the capacity margin range, the load is increased according to the power utilization shortage and the importance degree of the load, and the load is prevented from being cut off or increased frequently. The control system provided by the invention provides the working efficiency of the electric load in the station by adopting the control method.

Drawings

The invention is explained in more detail below with reference to the figures and examples.

Fig. 1 is a flowchart of a method for controlling an electrical load in a substation provided in an embodiment one;

fig. 2 is a flowchart of a method for controlling an electrical load in a substation provided in the second embodiment;

fig. 3 is a layout diagram of a control system for power consumption loads in a substation provided in the third embodiment;

fig. 4 is a layout diagram of a control system for an electric load in another substation provided in the fourth embodiment;

in fig. 1 to 4:

1. a class I load; 11. a communication room AC power supply; 12. an alternating current uninterrupted power supply; 13. a refrigeration system; 2. a class II load; 21. a pump power distribution box; 22. a first direct current system; 23. a second direct current system; 3. a class III load; 31. a secondary AC distribution panel; 32. an indoor lighting distribution box; 33. an outdoor lighting distribution box; 4. a switch; 5. a transformer; 10. a photovoltaic power generation device; 20. a diesel power generation device.

Detailed Description

In order to make the technical problems to be solved, the technical solutions to be adopted, and the technical effects to be achieved clearer, the technical solutions of the present embodiment will be further described in detail with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the scope of protection.

In the present description, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, releasably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present context can be understood in a specific case to those of ordinary skill in the art.

In this document, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact of the first and second features, or may comprise contact of the first and second features not directly but through another feature in between. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The technical solution of the present invention is further explained by the following embodiments with reference to the accompanying drawings.

The first embodiment is as follows:

as shown in fig. 1, the method for controlling an electrical load in a substation provided in this embodiment includes the following steps:

s100, dividing the load of the electric equipment into a plurality of types according to the importance degree;

s200, presetting a capacity margin range;

s300, obtaining the power shortage according to the difference value between the current electric load of the electric equipment and the current generating capacity of the current generating device;

s400, when the power utilization shortage is larger than the maximum capacity margin value of the capacity margin range, cutting off the load according to the power utilization shortage and the importance degree of the load; and when the power utilization shortage is smaller than the minimum capacity margin value of the capacity margin range, the load is increased according to the power utilization shortage and the importance degree of the load.

In this embodiment, step S100 specifically includes: dividing the load of the electric equipment group into a type I load, a type II load and a type III load according to the importance degree of the use purpose, wherein the type I load is a load which can influence the safety of a human body or equipment due to short-time power failure and enables the production operation to be stopped or the load of a main transformer to be reduced; the class II load is a load which allows short-time power failure, but has long power failure time and possibly influences normal production operation; the class III load is a load which cannot influence production operation due to long-time power failure.

In the present embodiment, in step S200: in the preset capacity margin range, the maximum capacity margin value is a positive number, the minimum capacity margin value can be a positive number or a negative number, and the specific numerical value can be set according to the actual operation condition of the system.

The principle of execution of step S400 is: in the process of cutting off the load, sequentially cutting off the load from a class III load to a class II load according to the importance degree of the load; in the process of increasing the load, the loads are increased in sequence from the class II load to the class III load according to the importance degree of the load. The I-type load is the most important load and can not be cut off, and when the I-type load is not cut off, the I-type load is not added.

Specifically, step S400 includes:

step S401, judging whether the power utilization shortage falls into the range of the capacity margin, if not, executing step S402, and if so, executing step S403;

step S402, judging whether the power shortage is greater than the maximum capacity margin value of the capacity margin range, if so, executing step S410, and if not, executing step S420;

step S410, judging whether the number of the power generation devices used currently is smaller than that of the power generation devices in the transformer substation and the loads used currently are I-type loads, if so, executing step S411; if not, go to step S412;

step S411, increasing the number of power generation devices connected with electric equipment, and returning to the step S300;

step S412, judging whether the total power of the currently used class III load is greater than or equal to the power shortage, if so, executing step S413, and if not, executing step S414;

step S413, selectively cutting off the currently used III-class load and returning to the step S300;

and step S414, after the III-class load is in an unused state, selectively cutting off the II-class load, and returning to the step S300.

When selectively cutting off loads in the same type of loads, judging the power consumption of a plurality of loads in the type of loads, and when the power consumption has larger difference, preferentially cutting off the load with the largest power consumption; when the difference of the electric power of a plurality of loads is small, the load connected with the feeder line with the least difference is preferentially cut off.

Step S420, determining whether all class II loads are in a use state, if not, performing step S421, and if so, performing step S422;

step S421, adding the load with the minimum electric power in the unused loads in the II type loads, and returning to the step S300;

in this step, when the electric power consumption is substantially equal to or less than the shortage of the electric power consumption among the plurality of unused loads, the load with the largest number of connecting feeders is selected to be added.

Step S422, judging the current lighting environment of the transformer substation, if the lighting environment is dark, executing step S423, and if not, executing step S403;

step S423, adding the load with the minimum power in the unused loads in the III-class loads, and returning to the step S300;

and step S403, maintaining the current operation state of the substation.

Example two:

as shown in fig. 2, the present embodiment is different from the first embodiment in that, after step S403, the present embodiment further includes:

step S500: checking the capacity load rate of the power generation device which operates currently, judging whether the capacity load rate is within a preset capacity load range, if not, performing the step S501, and if so, returning to the step S300;

step S501, judging whether the capacity load rate is smaller than the minimum value of the capacity load range, if so, executing step S502, and if not, executing step S505;

step S502, judging whether the number of the power generation devices currently used is smaller than the total number of the power generation devices of the transformer substation, if so, executing step S503, otherwise, executing step S504;

step S503, increasing the operation number of the power generation devices, and returning to the step S300;

step S504, load shedding is carried out according to the executing principle of the step S400, and the step S300 is returned;

step S505, determining whether the number of currently used power generation devices is 1, if not, performing step S506, and if so, performing step S507;

step S506, reducing the number of the power generation devices currently used, and returning to the step S300;

step S507, the load increase is performed according to the principle executed in step S400, and the process returns to step S300.

Example three:

in this embodiment, as shown in fig. 3, in the control system of the electrical load in the substation provided in the embodiment, the control method of the electrical load in the substation described in the first embodiment or the second embodiment may be adopted for control.

In this embodiment, the class I load 1 includes a communication room ac power supply 11, an ac uninterruptible power supply 12, and a refrigeration system 13.

The class II load 2 comprises a pump power distribution box 21 connected to the power plant by X feeders, a first dc system 22 connected to the power plant by Y feeders, and a second dc system 23 connected to the power plant by Z feeders. Specifically, the power of the pump power distribution box 21 is N kilowatts, the power of the first direct current system 22 is M kilowatts, the power of the second direct current system 23 is L kilowatts, and X, Y and Z are positive integers.

The class III load 3 includes a secondary ac distribution panel 31 connected to the power generation device by a feeder lines, an indoor lighting distribution panel 32 connected to the power generation device by b feeder lines, and an outdoor lighting distribution panel 33 connected to the power generation device by c feeder lines. Specifically, the power of the secondary ac distribution panel 31 is h kw, the power of the indoor lighting distribution box 32 is t kw, the power of the outdoor lighting distribution box 33 is q kw, and a, b, and c are positive integers.

Each feeder line is connected with a cut-off switch 4 and provided with a mutual inductor 5, and the mutual inductor 5 is used for calculating the real-time load condition of the feeder line.

Specifically, when all the class III loads 3 are in an unused state and the electricity shortage is greater than the maximum capacity margin value of the capacity margin range, the class II loads 2 need to be removed, for example, when N > M > L, the pump power distribution box 21 is cut off first, the first dc system 22 is cut off, and the second dc system 23 is cut off last, and when N > M ═ L and X > Y > Z, the second dc system 23 is cut off first, the first dc system 22 is cut off, and the pump power distribution box 21 is cut off last.

Specifically, when the class II loads 2 are not all in use and the power shortage is smaller than the minimum capacity margin value of the capacity margin range, the class II loads 2 need to be increased, for example, when N > M > L, the second dc system 23 is increased, the first dc system 22 is increased, and the pump power distribution box 21 is increased last, and when N > M ═ L and X > Y > Z, the pump power distribution box 21 is increased first, the first dc system 22 is increased, and the second dc system 23 is increased last.

Specifically, when the class III load 3 is partially in use and the shortage of electricity is greater than the maximum capacity margin value of the capacity margin range, the class III load 3 needs to be cut off, for example, when h > t > q, the secondary ac distribution panel 31 is cut off first, the indoor lighting distribution panel 32 is cut off, and the outdoor lighting distribution panel 33 is cut off last, and when h > t > q and a > b > c, the outdoor lighting distribution panel 33 is cut off first, the indoor lighting distribution panel 32 is cut off again, and the secondary ac distribution panel 31 is cut off last.

Specifically, when all the class II loads 2 are in use and the power shortage is smaller than the minimum capacity margin value of the capacity margin range, the class III load 3 needs to be increased, for example, when h > t > q, the outdoor lighting distribution box 33 is increased, the indoor lighting distribution box 32 is increased, the secondary ac distribution box 31 is increased, and when N ═ M ═ L and X > Y > Z, the secondary ac distribution box 31 is increased, the indoor lighting distribution box 32 is increased, and the outdoor lighting distribution box 33 is increased.

Specifically, the power generation device used at present at least comprises a photovoltaic power generation device 10 and a diesel power generation device 20, the diesel power generation device 20 has a higher power generation stability degree than the photovoltaic power generation device 10, the photovoltaic power generation device 10 is connected with a class II load 2 and a class III load 3, the photovoltaic power generation device 10 is used as a conventional power supply source of the class III load 3 and the class II load 2, the diesel power generation device 20 is connected with a class I load 1, the diesel power generation device 20 is used as a conventional power supply source of the class I load 1, clean energy is provided through the photovoltaic power generation device 10, pollution is reduced, and the diesel power generation device 20 is connected with the class I load 1, so that the power supply stability of the class I load 1.

In this embodiment, there are at least two types of power generation devices, and each type of power generation device is connected with loads of different importance levels according to different power generation stability levels. In this case, when step S200 in the first embodiment is executed, the capacity margin is preset for the loads connected to the same type of power generation device, that is, the class I load 1 is connected to the diesel power generation device alone, and the class II load 2 and the class III load 3 are connected to the photovoltaic power generation device 10 in common, so that the capacity margin of the class I load 1 is preset as the first capacity margin, and the total capacity margin of the class II load 2 and the class III load 3 is preset as the second capacity margin.

For convenience of description, the loads are grouped according to the connection condition of the loads and the power generation devices, and the loads connected with the same power generation device are used as the same group.

In step S300, for each group of loads, the power shortage of the group of loads is obtained according to the sum of the current electrical load and the corresponding capacity margin and the difference between the current electrical capacity of the power generation device connected to the group of loads.

In step S400, for each group of loads, the loads in the group are removed or added according to the power shortage of the group of loads.

Other steps can be performed with reference to the first embodiment or the second embodiment, and the description of this embodiment is omitted.

Example four:

as shown in fig. 4, the present embodiment is different from the third embodiment in that, in the present embodiment, when the class I load 1, the class II load 2, and the class III load 3 are connected to both the photovoltaic power generation apparatus 10 and the diesel power generation apparatus 20, the photovoltaic power generation apparatus 10 is selected as the normal power supply, and the diesel power generation apparatus 20 is used as the backup.

In this embodiment, since each of the power generation apparatuses is connected with various types of loads, in this case, in executing step S300 in the first embodiment, the power shortage is obtained according to the difference between the sum of the electric loads of all the loads currently used and the capacity margin and the sum of the current capacities of the current power generation apparatuses.

In the description herein, it is to be understood that the terms "upper", "lower", "left", "right", and the like are used in an orientation or positional relationship based on those shown in the drawings for convenience of description and simplicity of operation, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used merely for descriptive purposes and are not intended to have any special meaning.

In the description herein, references to the description of "an embodiment," "an example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

In addition, the foregoing is only the preferred embodiment and technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail with reference to the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the scope of the present invention, which is defined by the appended claims.

Claims

1. A method for controlling power utilization load in a substation is characterized by comprising the following steps:

presetting a capacity margin range;

2. The method for controlling the power utilization load in the substation station according to claim 1, characterized by comprising the steps of: the load of the electric equipment is divided into a plurality of types according to the importance degree, and the method specifically comprises the following steps:

3. The method for controlling the power consumption load in the substation station according to claim 2, characterized by comprising the steps of: the method for cutting off or adding the load specifically comprises the following steps:

4. The method for controlling the electrical load in a substation station according to claim 2,

when selectively cutting off the loads with the same level of importance, firstly cutting off the load with the least number of feeder lines in the currently used loads; and/or

5. The method for controlling the electrical load in a substation station according to claim 2,

when selectively cutting off the loads with the same level of importance, firstly cutting off the load with the largest electric power in the currently used loads; and/or

6. The method for controlling the power utilization load in the substation according to claim 2, wherein when the power utilization shortage is greater than the maximum capacity margin value of the capacity margin range, it is determined whether the number of the power generation devices currently used is less than the number of the power generation devices in the substation and the currently used loads are all class I loads, if so, the number of the power generation devices connected with the power utilization equipment is increased, the power utilization shortage is recalculated, and if not, the loads are removed.

7. The method for controlling the power consumption load in the substation according to claim 2, wherein in the process of adding the load, if all the class I loads and the class II loads in the substation are in a use state, whether the class III loads need to be added is judged according to a current lighting environment of the substation, and if the current lighting environment is a dark environment, the class III loads are added.

8. The substation intra-station power load control method according to claim 1, wherein before the power shortage is calculated, a load connection condition of a power generation device and the power utilization equipment is acquired:

9. The method for controlling the electrical load in the substation according to claim 1, wherein in the step of: after the load is cut off or added, the method also comprises the following steps: checking the capacity load rate of the power generation device which operates currently;

10. A control system, characterized in that the control system is controlled using the control method according to any one of claims 1-9.