Power grid operation control method and device, terminal and storage medium

Abstract

The present application relates to the technical field of power grid operation control, and particularly relates to a power grid operation control method, which acquires current waveforms and voltage waveforms of each power supply line, determines a grid-connected line of a distributed power supply, and determines an output current waveform of the distributed power supply according to the current waveform of the grid-connected line and the current waveform of a target bus section, so that the effects of peak clipping and valley filling and reactive power compensation can be achieved, and the power supply quality of the power grid is improved. The method determines defects of the power supply line in capacity, power factor and harmonic pollution through the current waveforms and voltage waveforms of each power supply line, and grid-connected power generation is performed on the distributed power supply and the line with the above defects, and the output current is directed to the capacity, power factor and harmonic pollution, so that the power supply line with the above problems is compensated or offset, smooth power supply of the power supply line is achieved, and unnecessary line consumption is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power grid planning operation control, and particularly relates to a power grid operation control method and device, a terminal and a storage medium. BACKGROUND

[0002] Electricity is a clean secondary energy. In order to ensure the sustainable development of society, more and more new energy and new energy storage devices will be applied to the power system. The application of new energy such as wind energy, solar energy and biomass energy is mostly in a decentralized manner, and the capacity is relatively small. These decentralized power generation devices, such as gas turbines, internal combustion engines, small photovoltaic power stations, fuel cells and wind turbines, which are arranged near the power load, have a capacity of several kilowatts to tens of megawatts, are environmentally compatible and energy-saving, and are referred to as distributed generation (DG).

[0003] The distributed generation is connected to the power grid system through the distribution network. The distribution network is composed of overhead lines, cables, towers, distribution transformers, disconnectors, reactive power compensation devices and some auxiliary facilities, and plays an important role in the distribution of electric energy in the power grid.

[0004] An existing view considers that although the distributed generation can utilize renewable energy as much as possible, it brings not small troubles to the operation safety of the power grid and the power generation of the power station. For example, the grid-connected power generation of the distributed generation has instability, which can cause the protection device in the distribution network to malfunction and reduce the reliability of power utilization. On the other hand, there are some undesirable factors in the operation of the existing power supply line, such as unbalanced load power utilization, high peak and low valley of power utilization in a short time, poor power quality, harmonic pollution, low power factor of power utilization equipment, and large line loss, which need to be solved by using new technologies and new methods.

[0005] As can be seen, the distributed generation brings challenges and opportunities to the planning, control and operation safety of the power grid. Therefore, it is necessary to develop and design a power grid operation control method to solve the problem of unstable factors in the operation of the power supply line in the prior art. SUMMARY

[0006] The present application provides a power grid operation control method, device, terminal and storage medium, which is used to solve the problem of unstable factors in the operation of the power grid in the prior art.

[0007] In a first aspect, the present application provides a power grid operation control method applied to a power grid with distributed generation, and the method comprises:

[0008] obtaining current waveforms and voltage waveforms of each power supply line;

[0009] determining a to-be-connected line according to the current waveform of each power supply line, the voltage waveform of each power supply line, and a preset condition, wherein the to-be-connected line is any one of the power supply lines;

[0010] connecting the distributed power supply to the to-be-connected line to generate power;

[0011] determining a grid-connected current waveform according to the current waveform of the to-be-connected line and the current waveform of a target bus section, wherein the target bus section is a bus section connected to the to-be-connected line, and the grid-connected current waveform is a current waveform output by the distributed power supply.

[0012] In a possible implementation, the preset condition includes a maximum current of each power supply line, a power factor limit, and a harmonic factor limit, and the determining of the to-be-connected line according to the current waveform of each power supply line and the preset condition includes:

[0013] obtaining an effective current value and a harmonic factor of each power supply line according to the current waveform of each power supply line;

[0014] selecting, from the power supply lines, a power supply line with an effective current value greater than the maximum current as the to-be-connected line;

[0015] if the effective current value of each power supply line is less than or equal to the maximum current, obtaining a power factor of each power supply line;

[0016] selecting, from the power supply lines, a power supply line with a power factor greater than the power factor limit as the to-be-connected line;

[0017] if the power factor of each power supply line is less than or equal to the power factor limit, selecting, from the power supply lines, a power supply line with a harmonic factor greater than the harmonic factor limit as the to-be-connected line.

[0018] In a possible implementation, the obtaining of the power factor of each power supply line includes:

[0019] determining the power factor of each power supply line according to the voltage waveform and the current waveform of each power supply line.

[0020] In a possible implementation, the determining of the grid-connected current waveform according to the current waveform of the to-be-connected line and the current waveform of the target bus section includes:

[0021] if the effective current value of the to-be-connected line is greater than the maximum current, taking a current waveform when the distributed power supply outputs maximum output power as the grid-connected current waveform.

[0022] In a possible implementation, the determination of the grid-connected current waveform according to the current waveform of the line to be connected to the grid and the current waveform of the target bus section comprises:

[0023] If the power factor of the line to be connected to the grid is greater than the power factor limit value, the reactive current waveform and the active current waveform of the target bus section are determined according to the voltage waveform of the line to be connected to the grid and the current waveform of the target bus section, wherein the reactive current waveform and the active current waveform each include a phase angle, a magnitude and a frequency of current.

[0024] The grid-connected current waveform is determined according to the reactive current waveform and the active current waveform.

[0025] In a possible implementation, the determination of the grid-connected current waveform according to the current waveform of the line to be connected to the grid and the current waveform of the target bus section comprises:

[0026] If the harmonic factor of the line to be connected to the grid is greater than the harmonic factor limit value, the harmonic waveform of the line to be connected to the grid is obtained, wherein the harmonic waveform includes a phase angle, a magnitude and a frequency of current.

[0027] The active current waveform of the target bus section is determined according to the voltage waveform of the line to be connected to the grid and the current waveform of the target bus section, wherein the active current waveform includes a phase angle, a magnitude and a frequency of current.

[0028] The grid-connected current waveform is determined according to the harmonic waveform and the active current waveform.

[0029] In a possible implementation, the grid-connected power generation of the distributed power supply and the line to be connected to the grid comprises:

[0030] The grid-connected power generation of the distributed power supply is stopped;

[0031] The distributed power supply is disconnected from the current power supply line;

[0032] The distributed power supply is connected to the line to be connected to the grid;

[0033] The distributed power supply starts to generate power with the line to be connected to the grid.

[0034] In a second aspect, an embodiment of the present application provides a power grid operation control device, comprising:

[0035] A waveform acquisition module is configured to acquire current waveforms and voltage waveforms of each power supply line.

[0036] The grid-connection selection module is configured to determine a line to be connected to the grid according to the current waveform, the voltage waveform of each power supply line and a preset condition, wherein the line to be connected to the grid is any one of the power supply lines;

[0037] The grid-connection control module is configured to connect the distributed power supply to the line to be connected to the grid to generate power; and

[0038] The current waveform control module is configured to determine a grid-connection current waveform according to the current waveform of the line to be connected to the grid and a current waveform of a target bus section, wherein the target bus section is a bus section connected to the line to be connected to the grid, and the grid-connection current waveform is a current waveform output by the distributed power supply.

[0039] In a third aspect, an embodiment of the present application provides a power grid operation control terminal, comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the method according to the first aspect or any possible implementation manner of the first aspect.

[0040] In a fourth aspect, an embodiment of the present application provides a computer readable storage medium, which stores a computer program, wherein the computer program is executable by a processor to implement the steps of the method according to the first aspect or any possible implementation manner of the first aspect.

[0041] Compared with the prior art, the embodiment of the present application has the following beneficial effects:

[0042] The power grid operation control method disclosed by the embodiment of the present application acquires the current waveform and the voltage waveform of each power supply line, determines the line to be connected to the grid of the distributed power supply, and determines the output current waveform of the distributed power supply according to the current waveform of the line to be connected to the grid and the current waveform of the target bus section, so that the peak load shifting and reactive power compensation can be realized, and the power supply quality of the power grid is improved.

[0043] The method determines the defects of the power supply line in capacity, power factor and harmonic pollution according to the current waveform and the voltage waveform of each power supply line, connects the distributed power supply to the line with the defects to generate power, outputs the current for the capacity, the power factor and the harmonic pollution, compensates or offsets the power supply line with the defects, realizes the smooth power supply of the power supply line, and reduces unnecessary line consumption. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort based on these drawings.

[0045] Figure 1 is a schematic diagram of a power grid structure with distributed power supply provided by the embodiments of the present application;

[0046] Figure 2 is a flow chart of a power grid operation control method provided by the embodiments of the present application;

[0047] Figure 3 is a schematic diagram of bus current analysis provided by the embodiments of the present application;

[0048] Figure 4 is a functional block diagram of a power grid operation control device provided by the embodiments of the present application;

[0049] Figure 5 is a functional block diagram of a power grid operation control terminal provided by the embodiments of the present application.

[0050] In the drawings:

[0051] 110 first ring network;

[0052] 111 ring network switch;

[0053] 120 second ring network;

[0054] 130 power distribution room;

[0055] 131 first power supply line;

[0056] 132 second power supply line;

[0057] 133 first tie switch;

[0058] 134 incoming line switch;

[0059] 135 outgoing line switch;

[0060] 136 bus section;

[0061] 141 first switch;

[0062] 142 second switch;

[0063] 143 third switch;

[0064] 144 fourth switch;

[0065] 150 substation;

[0066] 160 distributed power supply. DETAILED DESCRIPTION

[0067] In the following description, for purposes of explanation and not limitation, specific details are set forth such as particular architectures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application can be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known methods, devices, and

[0068] In order to make the objects, technical solutions and advantages of the present application clearer, the following will be described in conjunction with the accompanying drawings and specific embodiments.

[0069] The following will be described in detail the embodiments of the present application, the present example is implemented in the technical solutions of the present application as the premise, gives the detailed implementation and specific operation process, but the protection scope of the present application is not limited to the following examples.

[0070] Figure 1 The power grid structure with distributed power supply is shown.

[0071] In conjunction with the above power grid structure with distributed power supply, the embodiments of the present application will be discussed in detail.

[0072] The power grid structure with distributed power supply comprises a first ring network 110, a second ring network 120, a distribution room 130 and a first switch 141 station; the first ring network 110 and the second ring network 120 are respectively connected with two different transformer stations 150.

[0073] The distribution room 130 comprises a first power supply line 131, a second power supply line and a first tie switch 133, the first power supply line 131 and the second power supply line are respectively connected with the two ring networks, one end of the first tie switch 133 is connected with the first power supply line 131, and the other end of the first tie switch 133 is connected with the second power supply line.

[0074] The first switch 141 station comprises a first end, a second end and a third end, the first end is connected with the first power supply line 131, the second end is used for connecting the distributed power supply 160, and the third end is connected with the second power supply line.

[0075] Specifically, the first ring network 110 and the second ring network 120 are two independently running ring networks, and two transformer stations 150 supply power for them respectively.

[0076] The role of the distribution room 130 is to step down the power from the ring network and then distribute it to the next level of line, and the ring network is the source of its power. In the embodiment of the application, two power supply lines are provided in the distribution room 130, and the two power supply lines are connected with two ring networks respectively, so that when one of the ring networks stops running, the corresponding power supply line connected with it will be powered off, and after taking other measures (usually troubleshooting and isolation), the power supply of the other ring network can be transferred to the power supply line that is powered off by closing the contact switch, thereby achieving the purpose of ensuring the operation of the power supply line.

[0077] The switch station is the access end of the distributed power supply 160, which includes the commonly known wind power generation, solar power generation and other common renewable energy power generation methods, and may also include energy storage power stations and other forms of distributed power supply 160. Those skilled in the art should know that the above-mentioned enumeration is only a specific embodiment provided for easy understanding, not limitation.

[0078] The distributed power supply 160 is usually connected with a line of lower voltage level, and in the design, if it is as close to the load as possible, the transmission loss is smaller, and the application of the distributed power supply 160 is more beneficial.

[0079] One end of the switch station is connected with the distributed power supply 160, and the other two ends are connected with two power supply lines respectively. By changing the connection relationship among the three ends, the purpose of the distributed power supply 160 supplying power to any power supply line can be achieved. For example, in one application scenario, the second end is in communication with the third end, so as to realize the power transmission to the second power supply line. In another application scenario, the second end is disconnected with the first end and the third end, so as to realize the purpose of stopping the grid-connected power generation of the distributed power supply 160.

[0080] In one embodiment, the first switch station 141 includes a first switch 141 and a second switch 142.

[0081] The first end of the first switch 141 is connected with the first power supply line 131, and the second end of the second switch 142 is connected with the second power supply line. The second end of the first switch 141 and the first end of the second switch 142 are both used to connect the distributed power supply 160.

[0082] Specifically, one embodiment of the first switch station 141 is two switches used to connect the distributed power supply 160. One end of the two switches is used to connect the distributed power supply 160, and the other two ends are connected with two power supply lines respectively, so as to achieve the purpose of controlling the connection or disconnection of the distributed power supply 160 with the power supply line.

[0083] In an embodiment, the first power supply line 131 of the power distribution room 130 and the second power supply line of the power distribution room 130 each comprise an incoming line switch 134, an outgoing line switch 135 and a busbar section 136. The second end of the incoming line switch 134 and the first end of the outgoing line switch 135 are connected to the busbar section 136 respectively; the first end of the incoming line switch 134 of the first power supply line 131 is used to connect to the first ring network 110, and the first end of the incoming line switch 134 of the second power supply line is used to connect to the second ring network 120. One end of the first contact switch 133 is connected to the busbar section 136 of the first power supply line 131, and the other end of the first contact switch 133 is connected to the busbar of the second power supply line.

[0084] Specifically, each power supply line of the power distribution room 130 comprises two switches and a busbar section 136, and one end of each switch is connected to the busbar section 136 and the other end is connected to the ring network. Therefore, when one of the switches or the line connected to the switch fails (such as a ground fault), the switch can be turned off and the other switch can be turned on to achieve power supply from the other switch. As described above, the power supply line with two switches has more ways to deal with line faults and greatly improves reliability.

[0085] In an embodiment, the first end of the first switch 141 is connected to the first end of the incoming line switch 134 of the first power supply line 131, and the first end of the second switch 142 is connected to the first end of the incoming line switch 134 of the second power supply line.

[0086] Specifically, based on the above embodiment, the switch connection mode of the switch station is arranged to be connected to the side of the incoming line switch 134 close to the ring network. When the power supply line of the power distribution room 130 fails (such as a ground fault), the switch of the power distribution room 130 acts to simultaneously achieve the purpose of turning off the power generation of the distributed power supply 160, ensuring the reliable operation of the distributed power supply 160 and the safety of the power supply line in the power distribution room 130.

[0087] In an embodiment, the power distribution room 130 is at least two.

[0088] The power distribution rooms 130 are connected in series from the head to the tail. The first incoming line end of the power distribution room 130 at the head and the first outgoing line end of the power distribution room 130 at the tail are connected with the first ring network 110 respectively, and the second incoming line end of the power distribution room 130 at the head and the second outgoing line end of the power distribution room 130 at the tail are connected with the second ring network 120 respectively. The first outgoing line end of each power distribution room 130 is connected with the first incoming line end of the power distribution room 130 next to it, and the second outgoing line end of each power distribution room 130 is connected with the second incoming line end of the power distribution room 130 next to it. The first incoming line end is the first end of the incoming line switch 134 of the first power supply line 131, the first outgoing line end is the second end of the outgoing line switch 135 of the first power supply line 131, the second incoming line end is the first end of the incoming line switch 134 of the second power supply line, and the second outgoing line end is the second end of the outgoing line switch 135 of the second power supply line.

[0089] In an embodiment, the first switch 141 station further comprises a third switch 143 and a fourth switch 144. The second end of the third switch 143 and the first end of the fourth switch 144 are used for connecting the distributed power supply 160; the first end of the third switch 143 is connected with the second end of the outgoing line switch 135 of the first power supply line 131, and the second end of the fourth switch 144 is connected with the second end of the outgoing line switch 135 of the second power supply line.

[0090] Specifically, when multiple power distribution rooms 130 are applied, the multiple power distribution rooms 130 are connected with the ring network in a head-to-tail manner, and the two power distribution rooms 130 at the head and the tail in the multiple power distribution rooms 130 are connected with the ring network, thus forming a ring-shaped power supply structure. Once the power supply line of one of the power distribution rooms 130 fails, the switch of another power distribution room 130 can be used for power supply switching.

[0091] On the contrary, the first switch 141 station is provided with an additional two switches, which are used for connecting one end of the outgoing line switch 135 away from the bus section 136. Therefore, when reverse power supply is performed through the outgoing line switch 135, the two additional switches can be switched to achieve the purpose of continuous grid-connected power generation.

[0092] Based on Figure 1 The power grid structure shown, Figure 2 A flow chart of the power grid operation control method provided by the first aspect of the embodiment of the present application is shown, and the details are as follows:

[0093] In step 201, the current waveform and the voltage waveform of each power supply line are obtained.

[0094] In step 202, the line to be connected to the grid is determined according to the current waveform, the voltage waveform of each power supply line and the preset condition, wherein the line to be connected to the grid is any one of the power supply lines.

[0095] In some embodiments, the preset conditions include maximum current, power factor limit value and harmonic factor limit value of the power supply lines, and step 202 includes:

[0096] The effective current value and the harmonic factor of the power supply lines are obtained according to the current waveform of the power supply lines;

[0097] From the power supply lines, the power supply line with the effective current value greater than the maximum current is selected as the grid-connected line;

[0098] If the effective current value of the power supply lines is less than or equal to the maximum current, the power factor of the power supply lines is obtained;

[0099] From the power supply lines, the power supply line with the power factor greater than the power factor limit value is selected as the grid-connected line;

[0100] If the power factor of the power supply lines is less than or equal to the power factor limit value, from the power supply lines, the power supply line with the harmonic factor greater than the harmonic factor limit value is selected as the grid-connected line.

[0101] In some embodiments, the power factor of the power supply lines is obtained, including:

[0102] According to the voltage waveform and the current waveform of the power supply lines, the power factor of the power supply lines is determined.

[0103] Exemplarily, the power supply line is always expected to have smooth load of the load, without large fluctuation, and the load belongs to resistive load, the phase angle of the current and the voltage is 0, there is no reactive power, so as to reduce the loss of the line; it is also expected that the load does not generate or generates less harmonic pollution, etc., therefore, in the prior art, various technical means are adopted to balance the fluctuation of power consumption, increase the power factor, and reduce the harmonic pollution, on the other hand, the distributed power supply as a power supply end has a large controllable range, and can effectively compensate various load fluctuations and line loss in the power supply line.

[0104] Therefore, in the power grid structure of the embodiments of the present application, the distributed power supply is as close to the load end as possible, so as to reduce the transmission delay and loss between the distributed power supply and the load.

[0105] The current waveform and the voltage waveform of the power supply lines are obtained, and based on the current waveform and the voltage waveform of the power supply lines, the load state, the power factor and the harmonic factor of the power supply lines can be obtained.

[0106] For example, the effective value of the current in a power supply line can be obtained from the current waveform, and this effective value can reflect the load status of the power supply line.

[0107] The phase difference between the current waveform and the voltage waveform of the power supply line can be obtained, and the cosine value of this phase difference is the power factor.

[0108] By performing a Fourier transform on the current waveform of a power supply line, the fundamental wave and higher harmonics can be obtained. The amplitude of the higher harmonics can reflect the degree of harmonic pollution, that is, the harmonic factor.

[0109] We should address the problems of the three most common power supply lines in an orderly and step-by-step manner.

[0110] Generally speaking, a high load condition is a relatively critical condition. Therefore, when judging the grid connection of distributed power sources, the load condition of the line should be judged first. Power factor and harmonic pollution should only be considered if the load condition is within a controllable range.

[0111] The main problems caused by harmonic pollution are reduced efficiency in the production, transmission and utilization of electrical energy, overheating of electrical equipment, vibration and noise. More severe harmonic pollution can cause line insulation to age and shorten its service life. Therefore, when considering the management of power supply lines, the load of the line should be considered first, followed by the power factor, and finally harmonic pollution.

[0112] In step 203, the distributed power source is connected to the grid-connected line to generate electricity.

[0113] In some implementations, step 203 includes:

[0114] Stop the distributed power source from generating electricity in the grid; disconnect the distributed power source from the current power supply line; connect the distributed power source to the line to be connected to the grid; start the distributed power source to generate electricity in the line to be connected to the grid.

[0115] For example, Figure 1 The state shown is that the distributed power source 160 is connected to the grid and generates electricity with the first power supply line 131. When the second power supply line 132 is determined to be the line to be connected to the grid, the distributed power source 160 should be stopped first, the first switch 141 should be opened, the second switch 142 should be closed, and then the distributed power source and the second power supply line 132 should be started to generate electricity in parallel.

[0116] In step 204, the grid-connected current waveform is determined based on the current waveform of the line to be connected to the grid and the current waveform of the target bus segment, wherein the target bus segment is the bus segment connected to the line to be connected to the grid, and the grid-connected current waveform is the current waveform output by the distributed power source.

[0117] In some embodiments, step 204 comprises:

[0118] If the effective current values of the lines to be connected to the grid are all greater than the maximum current, the current waveform when the distributed power supply outputs the maximum output power is taken as the grid-connected current waveform.

[0119] In some embodiments, step 204 comprises:

[0120] If the power factor of the lines to be connected to the grid is greater than the power factor limit value, the reactive current waveform and the active current waveform of the target bus section are determined according to the voltage waveform of the lines to be connected to the grid and the current waveform of the target bus section, wherein the reactive current waveform and the active current waveform each include the phase angle, the amplitude, and the frequency of the current.

[0121] The grid-connected current waveform is determined according to the reactive current waveform and the active current waveform.

[0122] In some embodiments, step 204 comprises:

[0123] If the harmonic factor of the lines to be connected to the grid is greater than the harmonic factor limit value, the harmonic waveform of the lines to be connected to the grid is obtained, wherein the harmonic waveform includes the phase angle, the amplitude, and the frequency of the current.

[0124] The active current waveform of the target bus section is determined according to the voltage waveform of the lines to be connected to the grid and the current waveform of the target bus section, wherein the active current waveform includes the phase angle, the amplitude, and the frequency of the current.

[0125] The grid-connected current waveform is determined according to the harmonic waveform and the active current waveform.

[0126] Exemplarily, for a situation with heavy load, the distributed power supply generates power at the maximum power generation efficiency, and the maximum grid-connected power is achieved.

[0127] For a situation with low power factor, the distributed power supply can output reactive current to the bus section 136, so that the phase angle of the current and the voltage from the power supply line is close to 0°, so as to improve the power factor of the power supply line.

[0128] Referring to Figure 3 , the current 301 of the bus and the voltage 302 of the power supply line have an included angle, the bus current 301 can be decomposed into an active current and a reactive current 303 having an included angle of 90° with the active current, and the reactive current 303 comes from the power supply line, which is relatively long and causes relatively high line loss.

[0129] In the embodiment of the present application, the reactive current 303 is output by the distributed power supply 160, and the distributed power supply 160 determines the waveform according to the active current. Specifically, because the amplitude of the active current is constantly changing, the active current of the power supply line is usually taken as a relatively stable value, and the active current output by the distributed power supply is floating according to the change of the load, so that the peak clipping effect can be achieved.

[0130] The current waveform finally output by the distributed power supply is the superposition of the reactive current and the active current.

[0131] Similarly, for the harmonic control, the current waveform of the grid-connected line is subjected to Fourier transform to obtain high-order harmonics, then the distributed power supply generates a harmonic with the same amplitude, the same frequency and the opposite phase as the high-order harmonic, the harmonic is superimposed on the floating active current and is output to the grid to offset the harmonic pollution.

[0132] The embodiment of the present application provides a power grid operation control method for a power grid structure with a distributed power supply, the method acquires the current waveform and the voltage waveform of each power supply line, determines the grid-connected line of the distributed power supply, and determines the output current waveform of the distributed power supply according to the current waveform of the line to be grid-connected and the current waveform of the target bus section, so that the peak clipping and valley filling and reactive compensation effects can be achieved, and the power supply quality of the power grid is improved.

[0133] The method of the present application determines the defects of the power supply line in capacity, power factor and harmonic pollution according to the current waveform and the voltage waveform of each power supply line, grid-connects the distributed power supply with the line having the above defects, outputs the current for capacity, power factor and harmonic pollution, compensates or offsets the power supply line having the above problems, and realizes the smooth power supply of the power supply line and reduces unnecessary line consumption.

[0134] Figure 4 The embodiment of the present application provides a functional block diagram of the power grid operation control device.

[0135] The second aspect of the embodiment of the present application provides a power grid operation control device, which comprises a waveform acquisition module 401, a grid-connection selection module 402, a grid-connection control module 403 and a current waveform control module 404.

[0136] The waveform acquisition module 401 is used to acquire the current waveform and the voltage waveform of each power supply line.

[0137] The grid-connection selection module 402 is used to determine the line to be grid-connected according to the current waveform, the voltage waveform of each power supply line and a preset condition, wherein the line to be grid-connected is any one of the power supply lines.

[0138] a grid-connected control module 403, configured to connect the distributed power supply with the to-be-connected line to generate power; and

[0139] a current waveform control module 404, configured to determine a grid-connected current waveform according to a current waveform of the to-be-connected line and a current waveform of a target bus section, wherein the target bus section is a bus section connected with the to-be-connected line, and the grid-connected current waveform is a current waveform output by the distributed power supply.

[0140] Figure 5 is a functional block diagram of a terminal provided by an embodiment of the present application. As shown in the figure, the terminal 5 of the embodiment comprises a processor 500, a memory 501, and a computer program 502 stored in the memory 501 and executable on the processor 500. The processor 500 implements the steps in the above power grid operation control method and embodiments when executing the computer program 502, for example, the steps 201 to 204 shown in the figure. Figure 5 Figure 2

[0141] For example, the computer program 502 can be divided into one or more modules / units, which are stored in the memory 501 and executed by the processor 500 to complete the present application.

[0142] The terminal 5 can be a desktop computer, a notebook computer, a palm computer, a cloud server, and the like. The terminal 5 can include, but is not limited to, the processor 500 and the memory 501. Those skilled in the art can understand that Figure 5 The terminal 5 is only an example and does not constitute a limitation on the terminal 5, which can include more or fewer components than shown, or combine certain components, or different components, for example, the terminal can also include an input / output device, a network access device, a bus, and the like.

[0143] The processor 500 can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0144] ​​The memory 501 can be an internal storage unit of the terminal 5, for example, a hard disk or a memory of the terminal 5. The memory 501 can also be an external storage device of the terminal 5, for example, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the terminal 5. Further, the memory 501 can also include both the internal storage unit and the external storage device of the terminal 5. The memory 501 is used to store the computer program and other programs and data required by the terminal. The memory 501 can also be used to temporarily store data that has been output or is about to be output.

[0145] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above functional units and modules is exemplified, and in actual application, the above functions can be completed by different functional units and modules according to needs, that is, the internal structure of the apparatus is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiments can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit, and the integrated unit can be realized in the form of hardware or software. In addition, the specific names of each functional unit and module are only for easy distinction, and do not limit the protection scope of the present application. The specific working process of the units and modules in the system can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0146] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described or recorded in detail in a certain embodiment can refer to the relevant description of other embodiments.

[0147] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized in electronic hardware or a combination of computer software and electronic hardware. Whether the functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0148] In the embodiments of the present application, it should be understood that the disclosed apparatus / terminal and method can be implemented in other manners. For example, the apparatus / terminal embodiments described above are merely schematic, and the division of the modules or units is merely logical function division, and there can be other division manners in actual implementation. For example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual couplings or direct couplings or communication connections between different units, can be indirect couplings or communication connections through some interfaces, devices or units, and can be electrical, mechanical or in other forms.

[0149] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e., can be located in one place, or can be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the present embodiment.

[0150] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can be physically present separately, or two or more units can be integrated into one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0151] The integrated module / unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the above-mentioned embodiment methods can also be completed by a computer program instructing related hardware, and the computer program can be stored in a computer-readable storage medium. When the processor executes the computer program, the steps of each power grid operation control method and power grid operation control device embodiment described above can be implemented. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form, etc. The computer-readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the contents included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0152] The above-described embodiments are only used to illustrate the technical solutions of the present application, but not limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, those ordinarily skilled in the art should understand: the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A power grid operation control method, characterized in that, Applied to power grids with distributed generation, the method includes: Obtain the current and voltage waveforms of each power supply line; The line to be connected to the grid is determined based on the current waveform, voltage waveform and preset conditions of each power supply line, wherein the line to be connected to the grid is any one of the power supply lines. The distributed power source is connected to the grid-connected line to generate electricity. The grid-connected current waveform is determined based on the current waveform of the line to be connected to the grid and the current waveform of the target bus section, wherein the target bus section is the bus section connected to the line to be connected to the grid, and the grid-connected current waveform is the current waveform output by the distributed power source. The preset conditions include: the maximum current, power factor limit, and harmonic factor limit of each power supply line; the step of determining the line to be connected to the grid based on the current waveform of each power supply line and the preset conditions includes: The effective current value and harmonic factor of each power supply line are obtained based on the current waveform of each power supply line. From the power supply lines, select the power supply line whose effective current value is greater than the maximum current as the line to be connected to the grid; If the effective current value of each power supply line is less than or equal to the maximum current, then the power factor of each power supply line is obtained. From the power supply lines, select the power supply line with a power factor greater than the power factor limit as the line to be connected to the grid; If the power factor of each power supply line is less than or equal to the power factor limit, then the power supply line with a harmonic factor greater than the harmonic factor limit is selected from the power supply lines as the line to be connected to the grid. The step of determining the grid-connected current waveform based on the current waveform of the line to be connected to the grid and the current waveform of the target bus section includes: If the harmonic factor of the line to be connected to the grid is greater than the harmonic factor limit, then the harmonic waveform of the line to be connected to the grid is obtained, wherein the harmonic waveform includes the phase angle, amplitude and frequency of the current. Based on the voltage waveform of the line to be connected to the grid and the current waveform of the target bus section, the active current waveform of the target bus section is determined, wherein the active current waveform includes the phase angle, amplitude and frequency of the current. The grid-connected current waveform is determined based on the harmonic waveform and the active current waveform.

2. The power grid operation control method according to claim 1, characterized in that, The process of obtaining the power factor of each power supply line includes: The power factor of each power supply line is determined based on the voltage and current waveforms of each power supply line.

3. The power grid operation control method according to claim 1, characterized in that, The step of determining the grid-connected current waveform based on the current waveform of the line to be connected to the grid and the current waveform of the target bus section includes: If the effective current value of the line to be connected to the grid is greater than the maximum current, then the current waveform when the distributed power source outputs the maximum output power shall be used as the grid-connected current waveform.

4. The power grid operation control method according to claim 1, characterized in that, The step of determining the grid-connected current waveform based on the current waveform of the line to be connected to the grid and the current waveform of the target bus section includes: If the power factor of the line to be connected to the grid is greater than the power factor limit, then the reactive current waveform and active current waveform of the target bus segment are determined according to the voltage waveform of the line to be connected to the grid and the current waveform of the target bus segment. The reactive current waveform and the active current waveform both include the phase angle, amplitude and frequency of the current. The grid-connected current waveform is determined based on the reactive current waveform and the active current waveform.

5. The power grid operation control method according to any one of claims 1-4, characterized in that, The process of connecting the distributed power source to the grid-connected line for power generation includes: Stop the grid-connected power generation of the distributed power source; Disconnect the distributed power source from the current power supply line; Connect the distributed power source to the grid-connected line; The distributed power source starts generating electricity from the line to be connected to the grid.

6. A power grid operation control device, characterized in that, For implementing the power grid operation control method as described in any one of claims 1-5, the power grid operation control device comprises: The waveform acquisition module is used to acquire the current waveform and voltage waveform of each power supply line; The grid connection selection module is used to determine the line to be connected to the grid based on the current waveform, voltage waveform and preset conditions of each power supply line, wherein the line to be connected to the grid is any one of the power supply lines. Grid connection control module, used to connect distributed power sources to the grid-connected line for power generation; and, The current waveform control module is used to determine the grid-connected current waveform based on the current waveform of the line to be connected to the grid and the current waveform of the target bus segment, wherein the target bus segment is the bus segment connected to the line to be connected to the grid, and the grid-connected current waveform is the current waveform output by the distributed power source.

7. A power grid operation control terminal, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1 to 5 above.

8. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 5 above.

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