CN115912476A - Monitoring method and system for distributed power supply access node voltage - Google Patents
Monitoring method and system for distributed power supply access node voltage Download PDFInfo
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Abstract
The invention provides a method and a system for monitoring the voltage of a distributed power supply access node, wherein the method for monitoring the voltage of the distributed power supply access node comprises the following steps: collecting node voltage accessed by a distributed power supply through a distributed photovoltaic intelligent gateway; and carrying out data analysis on the node voltage, and carrying out optimal control on the node voltage by adopting a corresponding control strategy according to a data analysis result. According to the monitoring method of the distributed power supply access node voltage, the voltage monitoring and the local optimization control of the distributed power supply access node can be realized, so that the comprehensive utilization efficiency of distributed renewable energy sources is greatly improved.
Description
Technical Field
The invention relates to the technical field of distributed power supplies, in particular to a monitoring method and a monitoring system for distributed power supply access node voltage.
Background
With the rapid development of the distributed power supply technology, the photovoltaic permeability is higher and higher, a power distribution network area with high permeability of the distributed power supply is formed, the problems of backward feeding of feeder lines and local overvoltage occur, and a serious challenge is brought to the safe and reliable operation of the power distribution network. With the gradual promotion and construction of the power internet of things, the information acquisition and control of the distributed power supply also become an important basic link for constructing the power internet of things sensing layer.
In the related technology, the voltage data perception and the optimized control of the distributed power supply access node cannot be realized, and the comprehensive utilization efficiency of the distributed renewable energy is low.
Disclosure of Invention
In order to solve the technical problems, the invention provides a monitoring method for the voltage of the distributed power supply access node, which can realize the voltage monitoring and the local optimization control of the distributed power supply access node, thereby greatly improving the comprehensive utilization efficiency of distributed renewable energy sources.
The technical scheme adopted by the invention is as follows:
a monitoring method for distributed power supply access node voltage comprises the following steps: collecting node voltage accessed by the distributed power supply through a distributed photovoltaic intelligent gateway; and carrying out data analysis on the node voltage, and carrying out optimal control on the node voltage by adopting a corresponding control strategy according to a data analysis result.
In an embodiment of the present invention, acquiring, by the distributed photovoltaic intelligent gateway, the node voltage accessed by the distributed power supply includes: and collecting the node voltage accessed by the distributed power supply by adopting a communication mode or a direct-sampling direct-control mode through a distributed photovoltaic intelligent gateway.
In an embodiment of the present invention, the analyzing the data of the node voltage and performing optimal control on the node voltage by adopting a corresponding control strategy according to a result of the data analysis includes: extracting a positive sequence component of the node voltage; judging whether the positive sequence component is smaller than a first preset value or not; if the positive sequence component is smaller than the first preset value, acquiring the maximum active power according to the actual illumination intensity and the absolute temperature at the current moment; calculating a boundary voltage according to the maximum active power; judging whether the positive sequence component is larger than the boundary voltage or not; if the positive sequence component is larger than the boundary voltage, calculating a first given active current and a first given reactive current according to the positive sequence component and the boundary voltage, controlling an outer loop of an inverter voltage to be controlled to be disconnected, and directly giving the first given active current and the first given reactive current, wherein the boundary voltage is smaller than the first preset value; if the positive sequence component is smaller than or equal to the boundary voltage, judging whether the positive sequence component is larger than or equal to a second preset value, wherein the second preset value is smaller than the boundary voltage; if the positive sequence component is larger than or equal to the second preset value, calculating a second given active current and a second given reactive current according to the positive sequence component and the boundary voltage, controlling the outer ring of the inverter voltage to be disconnected, and directly giving the second given active current and the second given reactive current; and if the positive sequence component is smaller than the second preset value, calculating a third given active current and a third given reactive current according to the positive sequence component and the boundary voltage, controlling the outer ring of the inverter voltage to be disconnected, and directly giving the third given active current and the third given reactive current.
In an embodiment of the present invention, the performing data analysis on the node voltage and performing optimal control on the node voltage by adopting a corresponding control strategy according to a data analysis result includes: setting a voltage upper limit adjusting threshold, a locking voltage upper limit adjusting threshold, a voltage lower limit adjusting threshold, a locking voltage lower limit adjusting threshold and a voltage adjusting return threshold; dividing a plurality of voltage regulation areas according to the upper voltage limit regulation threshold, the upper locking voltage limit regulation threshold, the lower locking voltage limit regulation threshold and the return voltage regulation threshold; and confirming a voltage regulation area where the node voltage is located, and correspondingly adjusting the node voltage according to a confirmation result.
A system for monitoring a voltage at a distributed power supply access node, comprising: the acquisition module is used for acquiring the node voltage accessed by the distributed power supply through a distributed photovoltaic intelligent gateway; and the control module is used for carrying out data analysis on the node voltage and carrying out optimal control on the node voltage by adopting a corresponding control strategy according to a data analysis result.
A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and when the processor executes the computer program, the method for monitoring the voltage of the distributed power access node is implemented.
A non-transitory computer readable storage medium, having stored thereon a computer program which, when executed by a processor, implements the method of monitoring distributed power access node voltage described above.
The invention has the beneficial effects that:
the invention can realize the voltage monitoring and the local optimization control of the access node of the distributed power supply, thereby greatly improving the comprehensive utilization efficiency of the distributed renewable energy.
Drawings
Fig. 1 is a flowchart of a method for monitoring voltages of distributed power access nodes according to an embodiment of the present invention;
fig. 2 is a block diagram of a monitoring system for voltage of a distributed power access node according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the 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 protection scope of the present invention.
Fig. 1 is a flow chart of a method of monitoring a distributed power access node voltage according to an embodiment of the invention.
As shown in fig. 1, a method for monitoring voltages of distributed power access nodes according to an embodiment of the present invention may include the following steps:
s1, collecting node voltage accessed by a distributed power supply through a distributed photovoltaic intelligent gateway.
In one embodiment of the invention, the collecting node voltage accessed by the distributed power supply through the distributed photovoltaic intelligent gateway comprises the following steps: and collecting the node voltage accessed by the distributed power supply by adopting a communication mode or a direct-collecting direct-control mode through the distributed photovoltaic intelligent gateway.
Specifically, the distributed power supply access needs to acquire remote signaling and telemetry information in the distributed photovoltaic power station, such as current, voltage, and switch position at a common connection point, and perform corresponding control operation. The remote control of a circuit breaker, an electric isolating switch, an electric grounding disconnecting link, a photovoltaic power generation unit and the like at a common connection point is realized. And collecting and processing the state information of relay protection, action reports, fault recording waves and other related information. The acquisition of the telemetering information is kept relatively independent from the protection device, and the operation states of all primary equipment in the station, such as a circuit breaker, a disconnecting switch, a grounding switch, a transformer, a capacitor, the power utilization of an AC/DC station and the like, are directly acquired by the measurement and control unit. The distributed photovoltaic power generation information acquisition system mainly realizes the acquisition of information in the station through a distributed photovoltaic intelligent gateway, and the acquisition mode mainly comprises the following steps: a direct control mode and a communication mode.
When a direct sampling and direct control mode is adopted, a voltage transformer (PT) and a Current Transformer (CT) of a public connection point are directly connected to a distributed photovoltaic intelligent gateway alternating current sampling plug-in unit, so that voltage, current, active power, reactive power, power factor, frequency and harmonic wave of the public connection point of the distributed photovoltaic power station are calculated through a software measuring module. The circuit breaker position and other switch position (such as grounding disconnecting link, isolating switch and the like) contacts at the public connecting point are directly connected into the optical coupling switch-in plug-in component of the distributed photovoltaic intelligent gateway, so that the switch-on and switch-off positions of the switches are obtained through the software measuring module.
When the communication mode is adopted for collection, the running state information of the equipment such as the in-station inverter, the combiner box, the protective detection device, the electric energy quality on-line monitoring device, the environment detector, the watt-hour meter and the like is collected by the distributed photovoltaic intelligent gateway in the communication mode.
And S2, carrying out data analysis on the node voltage, and carrying out optimal control on the node voltage by adopting a corresponding control strategy according to a data analysis result.
In one embodiment of the invention, a control method based on a positive sequence component can be adopted as a low voltage ride through control strategy of the photovoltaic power generation system, so that a zero negative sequence component generated by a traditional control strategy is avoided, and reactive power support can be provided by a power distribution network. Since the duration of the fault is generally short and the ambient temperature and light intensity changes little during the fault phase, it is generally considered that the maximum power obtained during the fault is substantially constant. To reduce the response time of the photovoltaic power supply in the LVRT process, during which the power and voltage loops are locked, a given active current I can be directly given d_ref Given a reactive current I q_ref And (5) fixing the value, and adjusting the output magnitude of active power and reactive power.
Specifically, first, the positive sequence component of the node voltage can be extracted
And judges the positive sequence component->
Whether it is less than a first preset value (e.g., 0.9). If a positive sequence component>
If the value is greater than or equal to the first preset value, no adjustment is needed; if the positive sequence component->
If the actual illumination intensity S and the absolute temperature T at the current moment are less than the first preset value, the maximum active power P is obtained according to the actual illumination intensity S and the absolute temperature T at the current moment m And according to the maximum active power P m Calculating the boundary voltage U X 。
The physical nature of the photovoltaic cell is a PN junction, and when the photovoltaic cell is completely shaded, its performance can be approximated by the following diode equation:
in the formula, V T ＝k B T/q e Is a thermal voltage of a semiconductor material, k B Is Boltzmann constant (usually 1.381X 10-23J/K), T is absolute temperature, q is e Is unit charge (generally 1.602 multiplied by 10-19C); η is a diode quality factor, the value of which depends on the photovoltaic module manufacturing process and semiconductor materials; i is sat Is the reverse saturation current of the PN junction; n is s The number of photovoltaic modules in series is; n is p The number of the photovoltaic modules is parallel; i.e. i dk For steady state dark current, with an output voltage v pvk In strict incremental relationship, independent of the illumination intensity.
A part of current i greatly influenced by illumination intensity gck Called steady state photocurrent, equal to short circuit (v) at the output pvk = 0), the output current of the photovoltaic module is proportional to the illumination intensity, and may be specifically expressed as:
in the formula I sc The short-circuit current of the photovoltaic module under Standard Testing Conditions (STC) under which the illumination intensity S is measured ref ＝1000W/m 2 Temperature T of battery ref And the temperature is not less than 25 ℃, S is the actual illumination intensity, and alpha is the temperature coefficient of the short-circuit current.
Therefore, in practice, an equivalent model of the photovoltaic array can be represented by connecting an ideal PN junction and a light-controlled current source in parallel, and the photovoltaic array outputs current i pvk And the output voltage v pvk The relationship of (c) can be expressed as:
the formula (3) represents the nonlinear relation between the output current and the output voltage of the photovoltaic array under any illumination intensity and module temperature. The photovoltaic array may be equivalent to a variable current source whose output current is a non-linear function of the photovoltaic array voltage, i.e.
i pvk ＝f(v pvk )， (4)
Thus, the maximum output power of the photovoltaic array can be expressed as an expression of the output voltage, i.e.
P pvk ＝max(v pvk i pvk )＝max[v pvk f(v pvk )]| S,T ， (5)
Equation (5) shows that under different illumination conditions, the photovoltaic arrays have different maximum power points, and in order to obtain the maximum output power, each photovoltaic array adopts independent MPPT control. As can be seen from the equations (4) and (5), if the ambient temperature remains unchanged, the open-circuit voltage VOC of the photovoltaic array is less affected when the illumination intensity increases, and can be generally regarded as a constant; the maximum output power and the short-circuit current ISC increase with increasing illumination intensity, and decrease otherwise. The magnitude of the illumination intensity is therefore one of the important factors affecting the maximum output power of the photovoltaic array. If the illumination intensity is kept unchanged, when the temperature rises, the short-circuit current ISC is increased to a certain extent, and the increase amplitude is smaller; in contrast, the increase in temperature will cause the open-circuit voltage VOC to drop significantly and exhibit some linear relationship, resulting in a reduction in the maximum photovoltaic output power. Meanwhile, the working voltage of the photovoltaic power supply MPP will increase with decreasing temperature. Therefore, another important factor affecting the maximum power output of a photovoltaic power source is temperature.
Therefore, the maximum active power P can be obtained according to the actual illumination intensity S and the absolute temperature T at the current moment m 。
Further, according to the maximum active power P m The boundary voltage U can be calculated by the following formula X ：
Boundary voltage U X With maximum active power P captured only during a photovoltaic power failure m And the correlation trend is positive.
Secondly, the positive sequence component is determined
Whether or not it is greater than the boundary voltage U X . If the positive sequence component->
Greater than the boundary voltage U X Based on the positive sequence component->
And a boundary voltage U X Calculating a first given active current I d1_ref And a first given reactive current I q1_ref Wherein the first given active current I can be calculated by the following formula d1_ref And a first given reactive current I q1_ref ：
Further, the outer ring of the inverter voltage is controlled to be disconnected, and the first given active current I is directly given d1_ref And a first given reactive current I q1_ref Wherein the boundary voltage U X Less than the first preset value.
If the positive sequence component
Less than or equal to the boundary voltage U X If so, the positive sequence component is judged>
Whether or not it is greater than or equal to a second preset value (e.g., 0.2), wherein the second preset value is less than the boundary voltage U X . If the positive sequence component->
Greater than or equal to a second preset value, according to a positive sequence component->
And a boundary voltage U X Calculating a second given active current I d2_ref And a second given reactive current I q2_ref Wherein the second given active current I can be calculated by the following formula d2_ref And a second given reactive current I q2_ref ：
Furthermore, the voltage of the inverter is controlled to be disconnected by an outer ring control, and a second given active current I is directly given d2_ref And a second given reactive current I q2_ref 。
If the positive sequence component
Is less than a second preset value, based on the positive sequence component->
And a boundary voltage U X Calculating a third given active current I d3_ref And a third given reactive current I q3_ref Wherein the third given active current I is calculated by the following formula d3_ref And third given withoutWork current I q3_ref ：
Further, the outer ring of the inverter voltage is controlled to be disconnected, and a third given active current I is directly given d3_ref And a third given reactive current I q3_ref 。
Therefore, according to the control strategy, if the positive sequence voltage drop of the grid connection point is small, the photovoltaic power supply provides proper reactive output on the premise of keeping the active output stable; and when the detected positive sequence voltage drops greatly, the photovoltaic power supply preferentially provides reactive output.
In another embodiment of the invention, the local power automatic control can be used for regulating the voltage of the photovoltaic grid-connected point by regions, so that the photovoltaic grid-connected point can adapt to different access voltage levels, and the economic loss caused by voltage regulation is reduced.
Specifically, first, the upper limit voltage adjustment threshold U may be set hdb Threshold U for adjusting upper limit of locking voltage hlmt Threshold U for adjusting lower voltage limit ldb Locking voltage lower limit adjusting threshold U llmt Sum voltage regulation return threshold U th . Wherein the upper limit of the voltage is adjusted by a threshold U hdb Threshold U for adjusting upper limit of locking voltage hlmt Threshold U for adjusting lower voltage limit ldb Threshold U for adjusting lower limit of locking voltage llmt Sum voltage regulation return threshold U th The following size relationship is satisfied: u shape llmt ＜U ldb ＜U ldb +U th ＜U hdb -U th ＜U hdb ＜U hlmt 。
Secondly, the threshold U can be adjusted according to the upper limit of the voltage hdb Threshold U for adjusting upper limit of locking voltage hlmt Threshold U for adjusting lower voltage limit ldb Threshold U for adjusting lower limit of locking voltage llmt Sum voltage regulation return threshold U th A plurality of voltage regulation regions are divided.
Wherein, the divided voltage regulation areas may be: (0,U llmt ]、(U llmt ，U ldb )、(U ldb ，U ldb +U th ]、(U ldb +U th ，U hdb -U th )、[U hdb -U th ，U hdb )、[U hdb ，U hlmt )、[U hlmt ，+∞)。
And finally, confirming the voltage regulation area where the node voltage is positioned, and correspondingly adjusting the node voltage according to a confirmation result.
Specifically, if the node voltage is in the region of (0,U) llmt ]The voltage at the current sampling point is not adjusted.
If the node voltage is in the region of (U) llmt ，U ldb ]And increasing the reactive power of the photovoltaic inverter and not adjusting the active power of the photovoltaic inverter so as to increase the voltage of the current sampling point, wherein the specific method comprises the following steps:
(1) calculating the value of Q + delta Q;
(2) if Q + delta Q is less than or equal to Q max Then Q is sent to the photovoltaic inverter cmd An instruction of = Q + Δ Q;
(3) if Q + Δ Q > Q max Then Q is sent to the photovoltaic inverter cmd ＝Q max The instruction of (1).
Wherein Q is the photovoltaic reactive output before reactive regulation, delta Q is the step length for regulating the photovoltaic reactive output, Q max For photovoltaic reactive output maximum limit value, Q cmd And the photovoltaic reactive power is output after reactive power regulation.
If the node voltage is in the region of (U) ldb ，U ldb +U th ]The voltage at the current sampling point is not adjusted.
If the node voltage is in the region of [ U ] hlmt , + ∞), the voltage at the current sampling point is not adjusted.
If the node voltage is in the region of [ U ] hdb ，U hlmt ) Reducing the reactive power of the photovoltaic inverter firstly and then reducing the active power of the photovoltaic inverter so as to reduce the current sampling voltage, wherein the specific method comprises the following steps:
(1) calculating the value of Q-delta Q;
(2) if Q- Δ Q is not less than Q min (ii) a To the photovoltaic regionDischarging Q from inverter cmd Instruction of = Q- Δ Q, and no longer modulating active;
(3) if Q- Δ Q < Q min Then send Q to the photovoltaic inverter cmd ＝Q min And then calculates the value of P- Δ P;
(4) if P- Δ P.gtoreq.P min Then P is sent to the photovoltaic inverter cmd An instruction of = P- Δ P;
(5) if P- Δ P < P min Then give P to the photovoltaic inverter cmd ＝P min The instruction of (1).
Wherein Q is the reactive output of the photovoltaic before reactive regulation, delta Q is the step length for regulating the reactive output of the photovoltaic, and Q min For photovoltaic reactive output minimum limit, Q cmd For the reactive output of the photovoltaic after reactive regulation, P is the active output of the photovoltaic before active regulation, P is the step length for regulating the active output of the photovoltaic min Is the minimum limit value of active output, P, of the photovoltaic cmd The photovoltaic active output after active regulation.
If the node voltage is in the region of (U) ldb +U th ，U hdb -U th ) And node voltage is from region (U) llmt ，U ldb ]When the voltage rises to the area, the reactive power of the photovoltaic inverter is adjusted, and the active power of the photovoltaic inverter is not adjusted, so that the line loss is reduced, and the specific method comprises the following steps:
(1) if Q is more than delta Q/2, Q is sent to the photovoltaic inverter cmd An instruction of = Q- Δ Q;
(2) if Q is less than-delta Q/2, Q is sent to the photovoltaic inverter cmd An instruction of = Q + Δ Q;
(3) if Q is more than or equal to-delta Q/2 and less than or equal to delta Q/2, Q is sent to the photovoltaic inverter cmd Instruction of = 0.
Wherein Q is the reactive output of the photovoltaic before reactive regulation, delta Q is the step length for regulating the reactive output of the photovoltaic, and Q cmd And the photovoltaic reactive power is output after reactive power regulation.
If the node voltage is in the region of (U) ldb +U th ，U hdb -U th ) And the node voltage is from region [ U ] hdb ，U llmt ) When the temperature is lowered to the region, the adjustment is performed firstThe active power and the reactive power of the photovoltaic inverter are adjusted after the photovoltaic inverter, so that the active power output of the photovoltaic is increased, and the line loss is reduced, and the specific method comprises the following steps:
(1) calculating the value of P + delta P;
(2) if P + Δ P is less than or equal to P max Then P is sent to the photovoltaic inverter cmd Instruction of = P + Δ P, and no longer adjusts reactive;
(3) if P + Δ P > P max Then P is sent to the photovoltaic inverter cmd ＝P max And readjusting reactive power;
(4) if Q is more than delta Q/2; then Q is sent to the photovoltaic inverter cmd An instruction of = Q- Δ Q;
(5) if Q is less than-delta Q/2, Q is sent to the photovoltaic inverter cmd Instruction of = Q + Δ Q;
(6) if Q is more than or equal to-delta Q/2 and less than or equal to delta Q/2, Q is sent to the photovoltaic inverter cmd Instruction of =0
Wherein P is the active output of the photovoltaic before active regulation, delta P is the step length for regulating the active output of the photovoltaic, and P is max Is the maximum limit value of the active output of the photovoltaic, P cmd Is the active output of the photovoltaic after active regulation, Q is the reactive output of the photovoltaic before reactive regulation, delta Q is the step length for regulating the reactive output of the photovoltaic, Q cmd And the photovoltaic reactive power is output after reactive power regulation.
In summary, according to the monitoring method for the distributed power access node voltage in the embodiment of the invention, the distributed photovoltaic intelligent gateway is used for collecting the node voltage accessed by the distributed power, analyzing the data of the node voltage, and performing optimal control on the node voltage by adopting a corresponding control strategy according to the data analysis result. Therefore, voltage monitoring and local optimization control of the distributed power supply access node can be achieved, and comprehensive utilization efficiency of distributed renewable energy sources is greatly improved.
The invention further provides a monitoring system of the distributed power supply access node voltage, which corresponds to the monitoring method of the distributed power supply access node voltage of the embodiment.
As shown in fig. 2, a system for monitoring voltages of distributed power access nodes according to an embodiment of the present invention may include: an acquisition module 100 and a control module 200.
The acquisition module 100 is used for acquiring node voltage accessed by a distributed power supply through a distributed photovoltaic intelligent gateway; the control module 200 is configured to perform data analysis on the node voltage, and perform optimal control on the node voltage by using a corresponding control strategy according to a data analysis result.
In an embodiment of the present invention, the collecting module 100 is specifically configured to collect node voltages accessed by a distributed power supply through a distributed photovoltaic intelligent gateway in a communication manner or a direct control manner.
In an embodiment of the present invention, the control module 200 is specifically configured to: extracting a positive sequence component of the node voltage; judging whether the positive sequence component is smaller than a first preset value or not; if the positive sequence component is smaller than a first preset value, acquiring the maximum active power according to the actual illumination intensity and the absolute temperature at the current moment; calculating boundary voltage according to the maximum active power; judging whether the positive sequence component is larger than the boundary voltage or not; if the positive sequence component is larger than the boundary voltage, calculating a first given active current and a first given reactive current according to the positive sequence component and the boundary voltage, controlling the outer ring of the inverter voltage to be disconnected, and directly giving the first given active current and the first given reactive current, wherein the boundary voltage is smaller than a first preset value; if the positive sequence component is less than or equal to the boundary voltage, judging whether the positive sequence component is greater than or equal to a second preset value, wherein the second preset value is less than the boundary voltage; if the positive sequence component is greater than or equal to a second preset value, calculating a second given active current and a second given reactive current according to the positive sequence component and the boundary voltage, controlling the outer ring of the voltage of the inverter to be disconnected, and directly giving the second given active current and the second given reactive current; and if the positive sequence component is smaller than a second preset value, calculating a third given active current and a third given reactive current according to the positive sequence component and the boundary voltage, controlling the outer ring of the inverter voltage to be disconnected, and directly giving the third given active current and the third given reactive current.
In an embodiment of the present invention, the control module 200 is specifically configured to: setting a voltage upper limit adjusting threshold, a locking voltage upper limit adjusting threshold, a voltage lower limit adjusting threshold, a locking voltage lower limit adjusting threshold and a voltage adjusting return threshold; dividing a plurality of voltage regulation areas according to the voltage upper limit regulation threshold, the locking voltage upper limit regulation threshold, the voltage lower limit regulation threshold, the locking voltage lower limit regulation threshold and the voltage regulation return threshold; and confirming the voltage regulation area where the node voltage is positioned, and correspondingly adjusting the node voltage according to a confirmation result.
It should be noted that, the monitoring system of the distributed power supply access node voltage according to the embodiment of the present invention may refer to the embodiment of the monitoring method of the distributed power supply access node voltage, and details are not described herein again.
According to the monitoring system of the distributed power supply access node voltage, the acquisition module acquires the node voltage accessed by the distributed power supply through the distributed photovoltaic intelligent gateway, the control module analyzes the data of the node voltage, and the corresponding control strategy is adopted to optimally control the node voltage according to the data analysis result. Therefore, the control module is used for carrying out data analysis on the node voltage and adopting a corresponding control strategy to carry out optimization control on the node voltage according to the data analysis result.
The invention further provides a computer device corresponding to the embodiment.
The computer device of the embodiment of the invention comprises a memory, a processor and a computer program which is stored on the memory and can run on the processor, and when the processor executes the program, the monitoring method of the voltage of the distributed power supply access node of the embodiment is realized.
According to the computer equipment provided by the embodiment of the invention, the control module is used for carrying out data analysis on the node voltage and adopting a corresponding control strategy to carry out optimization control on the node voltage according to the data analysis result.
The invention also provides a non-transitory computer readable storage medium corresponding to the above embodiment.
A non-transitory computer-readable storage medium of an embodiment of the present invention stores thereon a computer program, which when executed by a processor implements the monitoring method of the distributed power supply access node voltage of the above-described embodiment.
According to the non-transitory computer-readable storage medium of the embodiment of the invention, the control module is used for carrying out data analysis on the node voltage and carrying out optimal control on the node voltage by adopting a corresponding control strategy according to the data analysis result.
In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. The meaning of "plurality" is two or more unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
In the description of the specification, reference to the description of "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" or the like means 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 of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and alternate implementations are included within the scope of the preferred embodiment of the present invention in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present invention.
The logic and/or steps represented in the flowcharts or otherwise described herein, e.g., an ordered listing of executable instructions that can be considered to implement logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.
It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or combination of the following technologies, which are well known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.
It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when the program is executed, the program includes one or a combination of the steps of the method embodiments.
In addition, functional units in the embodiments of the present invention may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.
The storage medium mentioned above may be a read-only memory, a magnetic or optical disk, etc. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (7)
1. A monitoring method for distributed power supply access node voltage is characterized by comprising the following steps:
collecting node voltage accessed by the distributed power supply through a distributed photovoltaic intelligent gateway;
and carrying out data analysis on the node voltage, and carrying out optimal control on the node voltage by adopting a corresponding control strategy according to a data analysis result.
2. The method for monitoring the voltage of the distributed power access node according to claim 1, wherein the collecting the voltage of the node accessed by the distributed power through the distributed photovoltaic intelligent gateway includes:
and collecting the node voltage accessed by the distributed power supply by adopting a communication mode or a direct control mode through a distributed photovoltaic intelligent gateway.
3. The method for monitoring the voltage of the distributed power access node according to claim 1, wherein the analyzing the data of the node voltage and performing optimal control on the node voltage by adopting a corresponding control strategy according to the data analysis result comprises:
extracting a positive sequence component of the node voltage;
judging whether the positive sequence component is smaller than a first preset value or not;
if the positive sequence component is smaller than the first preset value, acquiring the maximum active power according to the actual illumination intensity and the absolute temperature at the current moment;
calculating a boundary voltage according to the maximum active power;
judging whether the positive sequence component is larger than the boundary voltage or not;
if the positive sequence component is larger than the boundary voltage, calculating a first given active current and a first given reactive current according to the positive sequence component and the boundary voltage, controlling the outer loop of the inverter voltage to control disconnection, and directly giving the first given active current and the first given reactive current, wherein the boundary voltage is smaller than the first preset value;
if the positive sequence component is smaller than or equal to the boundary voltage, judging whether the positive sequence component is larger than or equal to a second preset value, wherein the second preset value is smaller than the boundary voltage;
if the positive sequence component is greater than or equal to the second preset value, calculating a second given active current and a second given reactive current according to the positive sequence component and the boundary voltage, controlling the outer loop of the inverter voltage to be disconnected, and directly giving the second given active current and the second given reactive current;
and if the positive sequence component is smaller than the second preset value, calculating a third given active current and a third given reactive current according to the positive sequence component and the boundary voltage, controlling the outer ring of the inverter voltage to be disconnected, and directly giving the third given active current and the third given reactive current.
4. The method for monitoring the voltage of the distributed power access node according to claim 1, wherein the analyzing the data of the node voltage and performing optimal control on the node voltage by adopting a corresponding control strategy according to the data analysis result comprises:
setting a voltage upper limit adjusting threshold, a locking voltage upper limit adjusting threshold, a voltage lower limit adjusting threshold, a locking voltage lower limit adjusting threshold and a voltage adjusting return threshold;
dividing a plurality of voltage regulation areas according to the upper voltage limit regulation threshold, the upper locking voltage limit regulation threshold, the lower locking voltage limit regulation threshold and the return voltage regulation threshold;
and confirming a voltage regulation area where the node voltage is located, and correspondingly adjusting the node voltage according to a confirmation result.
5. A monitoring system for a distributed power supply access node voltage, comprising:
the acquisition module is used for acquiring the node voltage accessed by the distributed power supply through a distributed photovoltaic intelligent gateway;
and the control module is used for carrying out data analysis on the node voltage and adopting a corresponding control strategy to carry out optimal control on the node voltage according to a data analysis result.
6. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the method of monitoring a distributed power access node voltage according to any one of claims 1 to 3 when executing the computer program.
7. A non-transitory computer readable storage medium having stored thereon a computer program, characterized in that the program, when executed by a processor, implements a method of monitoring distributed power access node voltages according to any of claims 1-3.
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