A power inversion control method based on dual constant normal cell and related device

Abstract

The application discloses a power inversion control method based on a double-constant straight unit and related equipment, and the method comprises the following steps: acquiring the current station-level total transmission power of the double-constant straight unit, and comparing the current station-level total transmission power with a preset power threshold interval; if the current station-level total transmission power is greater than the upper limit of the preset power threshold interval, the double-constant straight unit is controlled to switch a double-unit mode, and the current station-level transmission power is adjusted in response to a power instruction; if the current station-level total transmission power is less than the lower limit of the preset power threshold interval, the double-constant straight unit is controlled to switch a loop power mode, and the current station-level transmission power is power-cross-zero-inverted in response to the power instruction; and if the current station-level total transmission power falls within the preset power threshold interval, the double-constant straight unit is controlled to switch a single-unit mode, and the current station-level transmission power is power-down-regulated in response to the power instruction. The embodiment of the application can improve the system operation flexibility. The application can be widely applied to the technical field of power systems.

Description

Technical Field

[0001] This application relates to the field of power system technology, and in particular to a power reversal control method and related equipment based on dual constant DC units. Background Technology

[0002] Traditional power reversal requires two sets of units to operate synchronously and in coordination. Each set of units is subject to minimum power constraints due to thyristor characteristics and control limitations. It is difficult to achieve continuous and precise bidirectional adjustment under low load, when the power drops to near zero, and during power flow reversal, resulting in low operational flexibility. Summary of the Invention

[0003] The main objective of this application is to propose a power reversal control method and related equipment based on dual constant direct units, which can improve operational flexibility.

[0004] To achieve the above objectives, one aspect of this application proposes a power inversion control method based on dual constant direct units, the method comprising: Obtain the current station-level total transmission power and compare the current station-level total transmission power with a preset power threshold range; If the current station-level total transmission power is greater than the upper limit of the preset power threshold range, the dual constant direct unit is controlled to switch to dual unit mode, and in response to the power command, the current station-level total transmission power is adjusted according to the preset power ramp rate; If the current station-level total transmission power is greater than or equal to the lower limit of the preset power threshold range and less than or equal to the upper limit of the preset power threshold range, the dual constant direct unit is controlled to switch to single unit mode, and in response to the power command, the current station-level total transmission power is reduced according to the preset power ramp rate. If the current station-level total transmission power is less than the lower limit of the preset power threshold range, the dual constant direct unit is controlled to switch to loop power mode, and in response to the power command, the current transmission power is adjusted to zero according to the preset power ramp rate.

[0005] In some embodiments, the control of switching the dual constant direct unit to dual unit mode specifically includes: The dual constant direct current units are tested to determine healthy constant direct current units and locked constant direct current units, and the healthy constant direct current units are tested to determine the target voltage polarity and unit firing angle; The locked constant direct unit is unlocked according to the unit trigger angle to obtain the first unit; and the first unit is boosted according to the target voltage polarity and the preset voltage adjustment rate, and the current voltage value of the first unit is compared with the preset voltage threshold. If the current voltage value is less than the preset voltage threshold, return to the step of boosting the first unit according to the target voltage polarity and the preset voltage adjustment rate; If the current voltage value is greater than or equal to the preset voltage threshold, the boost operation on the first unit is stopped, and the second unit is obtained. The second unit is then boosted according to the preset current adjustment rate and the preset current threshold to obtain a dual-unit mode dual constant DC unit.

[0006] In some embodiments, controlling the dual constant direct unit to switch to single unit mode specifically includes: The dual constant current unit is analyzed to determine the target unit, and the current of the target unit is reduced according to the preset trigger angle. The current value of the target unit is then compared with the second preset current threshold. If the current value is greater than the second preset current threshold, return to the step of reducing the current of the target unit according to the preset trigger angle; If the current value is less than or equal to the second preset current threshold, the current reduction process for the target unit is stopped, and a third unit is obtained. The third unit is then subjected to voltage reduction processing according to the preset voltage adjustment rate and the second preset voltage threshold to obtain a dual constant DC unit in single-unit mode.

[0007] In some embodiments, controlling the dual constant DC unit to switch to loop power mode specifically includes: The dual constant straight unit is analyzed to determine the target locking unit, and the fourth unit is obtained by performing a locking and unlocking operation on the target locking unit. The power of the fourth unit is restored according to the preset power ramp rate, and the current power value of the fourth unit is detected and compared with the preset power threshold. If the current power value is greater than or equal to the preset power threshold, power recovery for the fourth unit is stopped, and a dual constant DC unit in loop power mode is obtained. If the current power value is less than the preset power threshold, return to the step of restoring the power of the fourth unit according to the preset power ramp rate.

[0008] In some embodiments, the loop power mode further includes: The loop power mode dual constant DC units are divided according to the preset unit type to determine the constant power unit and the power inversion unit. The constant power unit is controlled according to a preset power, and the power reversal unit is adjusted according to the power command and the preset ramp rate.

[0009] In some embodiments, the method further includes: Obtain the current power direction and compare it with a preset direction type to determine the current direction type; If the current direction type is positive, the first unit in the dual constant direct unit is divided into a constant power unit, the second unit in the dual constant direct unit is divided into a power reversal unit, and the process of controlling the power of the constant power unit according to the preset power and adjusting the power of the power reversal unit according to the power command and the preset ramp rate is returned to be executed. If the current direction type is reverse, the first unit in the dual constant direct unit is divided into a power inversion unit, the second unit in the dual constant direct unit is divided into a constant power unit, and the process returns to perform power control on the constant power unit according to the preset power, and power adjustment on the power inversion unit according to the power command and the preset ramp rate.

[0010] To achieve the above objectives, another aspect of this application proposes a power inversion control system based on dual constant direct units, the system comprising: The acquisition module is used to acquire the current station-level total transmission power and compare the current station-level total transmission power with a preset power threshold range; The control module is used to control the dual constant direct unit to switch to dual unit mode if the current station-level total transmission power is greater than the upper limit of the preset power threshold range, and to adjust the current station-level total transmission power according to the preset power ramp rate in response to the power command. If the current station-level total transmission power is greater than or equal to the lower limit of the preset power threshold range and less than or equal to the upper limit of the preset power threshold range, the dual constant direct unit is controlled to switch to single unit mode, and in response to the power command, the current station-level total transmission power is reduced according to the preset power ramp rate. If the current station-level total transmission power is less than the lower limit of the preset power threshold range, the dual constant direct unit is controlled to switch to loop power mode, and in response to the power command, the current transmission power is reversed across zero according to the preset power ramp rate.

[0011] To achieve the above objectives, another aspect of this application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the method described above.

[0012] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the methods described above.

[0013] To achieve the above objectives, another aspect of the embodiments of this application proposes a computer program product, including a computer program that, when executed by a processor, implements the aforementioned method.

[0014] The embodiments of this application include at least the following beneficial effects: This application provides a power reversal control method, system, electronic device, storage medium, and program product based on dual constant direct current units. This scheme obtains the current station-level total transmission power of the dual constant direct current units and compares the current station-level total transmission power with a preset power threshold range. If the current station-level total transmission power is greater than the upper limit of the preset power threshold range, the dual constant direct current units are controlled to switch to dual-unit mode, and power adjustment is performed on the current station-level transmission power in response to power commands. If the current station-level total transmission power is less than the lower limit of the preset power threshold range, the dual constant direct current units are controlled to switch to loop power mode, and power zero-crossing reversal is performed on the current station-level transmission power in response to power commands. If the current station-level total transmission power falls within the preset power threshold range, the dual constant direct current units are controlled to switch to single-unit mode, and power reduction is performed on the current station-level transmission power in response to power commands. By setting different modes of the dual constant direct current units and switching them based on the set power threshold range, smooth power zero crossing and improved power scheduling range are achieved, thereby improving the system's operational flexibility. Attached Figure Description

[0015] Figure 1 This is a flowchart of a power inversion control method based on dual constant direct units provided in an embodiment of this application; Figure 2 yes Figure 1 The flowchart of step S102 in the document; Figure 3 yes Figure 1 The flowchart of step S103 in the process; Figure 4 yes Figure 1 The flowchart of step S104 in the process; Figure 5 yes Figure 1 Another flowchart of step S104 in the process; Figure 6 yes Figure 1 The flowchart for step S104 of the diagram shows the zero-crossing inversion. Figure 7 This is a schematic diagram of the structure of a power reversal control method applied in a specific embodiment provided in this application; Figure 8This is a schematic diagram illustrating mode switching in a specific embodiment provided in this application. Figure 9 (a)- Figure 9 (d) is a schematic diagram of current, voltage and power changes in a specific embodiment of the present application when switching to single-unit mode; Figure 10 (a)- Figure 10 (d) is a schematic diagram of current, voltage and power changes in a switching loop power mode in a specific embodiment provided in this application; Figure 11 This is a schematic diagram of power changes and corresponding modes during power reversal in a specific embodiment provided in this application; Figure 12 This is a schematic diagram of a power reversal control system based on dual constant direct units provided in an embodiment of this application; Figure 13 This is a schematic diagram of the hardware structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.

[0017] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various concepts, but unless otherwise stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the words “if,” “when,” or “in response to a determination” as used herein may be interpreted as “when…” or “when…” or “in response to a determination.”

[0018] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.

[0020] Before providing a detailed description of the embodiments of this application, some of the nouns and terms involved in the embodiments of this application will be explained first. The nouns and terms involved in the embodiments of this application are subject to the following interpretations.

[0021] This application provides a power inversion control method based on dual constant direct units, relating to the field of information technology. This power inversion control method based on dual constant direct units can be applied to terminals, servers, or software running on either terminal or server. In some embodiments, the terminal can be a smartphone, tablet, laptop, desktop computer, smart speaker, smartwatch, or vehicle terminal, but is not limited to these. The server can be configured as an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDN, and big data and artificial intelligence platforms. The server can also be a node server in a blockchain network. The software can be an application implementing a power inversion control method based on dual constant direct units, but is not limited to the above forms.

[0022] This application can be used in a wide variety of general-purpose or special-purpose computer system environments or configurations. Examples include: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, and distributed computing environments including any of the above systems or devices. This application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform specific tasks or implement specific abstract data types. This application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices.

[0023] Figure 1 This is an optional flowchart of a power inversion control method based on dual constant DC units provided in an embodiment of this application. Figure 1The method may include, but is not limited to, steps S101 to S104.

[0024] Step S101: Obtain the current station-level total transmission power and compare the current station-level total transmission power with the preset power threshold range; Step S102: If the current station-level total transmission power is greater than the upper limit of the preset power threshold range, control the dual constant DC unit to switch to dual unit mode, and in response to the power command, adjust the current station-level total transmission power according to the preset power ramp rate. Step S103: If the current station-level total transmission power is greater than or equal to the lower limit of the preset power threshold range and less than or equal to the upper limit of the preset power threshold range, control the dual constant DC unit to switch to single unit mode, and in response to the power command, reduce the current station-level total transmission power according to the preset power ramp rate. Step S104: If the current station-level total transmission power is less than the lower limit of the preset power threshold range, control the dual constant DC unit to switch to loop power mode, and respond to the power command to perform power zero-crossing reversal on the current transmission power according to the preset power ramp rate.

[0025] In the embodiments of this application, steps S101 to S104 involve setting up two sets of LCC-HVDC units (line-converter type DC transmission units) within the DC engineering of the power grid as the main high-power switching channels of the power grid. These two sets of units form a dual-constant DC unit to regulate and convert the DC power transmitted from the power grid. The dual-constant DC unit detects the current station-level total transmission power input to the dual-constant DC unit using sensors, compares the detected current station-level total transmission power with a preset threshold range, determines the power range in which the current station-level total transmission power is located, and switches the operating mode of the dual-constant DC unit according to the power range, including dual-unit mode, single-unit mode, and loop power mode, to achieve different operating characteristics and feasible power ranges. This allows for wide-range power adjustment and smooth zero-crossing of the input DC power, achieving power reversal. If the current station-level total transmission power is greater than... When the upper limit of the set threshold range is reached, the system is in the high-power region, and the dual constant DC units are in dual-unit mode, with both sets of units operating simultaneously and bearing the same power. If the total transmission power at the current station level falls within the preset threshold range, the system is in the medium-power region, and the dual constant DC units are in single-unit mode, keeping one set of units operating while the other set is locked out. The operating unit then adjusts the input DC power and can lower the DC power to the minimum power constraint value of a single unit. If the total transmission power at the current station level is less than the lower limit of the preset threshold range, the system is in the low-power region, and the dual constant DC units are in loop power mode. The dual constant DC units unlock the units locked out in single-unit mode, and both sets of units operate simultaneously, but with opposite power directions, forming a controllable circulating current. Through this controllable circulating current, the system operates at extremely low power and achieves smooth zero-crossing reversal.

[0026] Please see Figure 2 In some embodiments, step S102 may include, but is not limited to, steps S201 to S204: Step S201: Detect the dual constant DC unit to determine the healthy constant DC unit and the locked constant DC unit, and detect the healthy constant DC unit to determine the target voltage polarity and unit firing angle; Step S202: Unlock the locked constant DC unit according to the unit trigger angle to obtain the first unit; and perform a voltage boosting operation on the first unit according to the target voltage polarity and the preset voltage adjustment rate, and compare the current voltage value of the first unit with the preset voltage threshold. Step S203: If the current voltage value is less than the preset voltage threshold, return to execute the voltage boosting operation of the first unit according to the target voltage polarity and the preset voltage adjustment rate; Step S204: If the current voltage value is greater than or equal to the preset voltage threshold, stop the boost operation of the first unit to obtain the second unit, and perform a current boost operation on the second unit according to the preset current adjustment rate and the preset current threshold to obtain a dual constant DC unit in dual unit mode.

[0027] In step S201 of some embodiments, the controller detects the running dual constant DC unit. At this time, the dual constant DC unit is running in single unit mode. The controller determines the healthy constant DC unit and the locked constant DC unit in the dual constant DC unit through detection. The controller performs a lockout operation on the locked constant DC unit to restore conduction operation and switch to dual unit mode. After determining the healthy constant DC unit, the controller detects the healthy constant DC unit to determine the voltage polarity and trigger angle of the healthy constant DC unit so that the dual constant DC units can be synchronized after the locked unit is unlocked.

[0028] In step S202 of some embodiments, the controller triggers the inverter and rectifier connected to the lockout unit according to the detected firing angle to unlock the lockout and enable the lockout unit to handle the input DC power; then the controller determines the current DC power transmission direction according to the detected voltage polarity of the healthy DC unit; then the controller determines the voltage polarity or power transmission direction of the unlocked DC unit according to the voltage polarity or power transmission direction; then the controller performs a boost operation on the DC unit according to a preset voltage adjustment rate and monitors the voltage of the DC unit in real time according to a preset voltage threshold.

[0029] In step S203 of some embodiments, if the current voltage value of the unlocked DC unit is detected to be less than a preset voltage threshold, the controller performs a boost operation on the unlocked DC unit according to a preset voltage adjustment rate until the voltage of the unlocked DC unit reaches the preset voltage threshold.

[0030] In step S204 of some embodiments, if the current voltage value of the unlocked constant DC unit is detected to be greater than or equal to a set voltage threshold, the controller stops the boost operation on the unlocked constant DC unit, obtaining a constant DC unit with a stable voltage platform; then, the controller performs a current boost operation on the constant DC unit with a stable voltage platform according to a preset current adjustment rate, and monitors the current of the constant DC unit in real time according to a preset current threshold until the monitored unit current is greater than or equal to the preset current threshold, the controller stops the current boost operation on the constant DC unit, completes the mode switch, and obtains a dual constant DC unit operating in dual unit mode; in this embodiment, the voltage threshold and current threshold are determined based on the voltage and current values ​​of the healthy constant DC unit.

[0031] Please see Figure 3In some embodiments, step S103 may include, but is not limited to, steps S301 to S303: Step S301: Analyze the dual constant current unit, determine the target unit, reduce the current of the target unit according to the preset firing angle, and compare the current value of the target unit with the second preset current threshold. Step S302: If the current value is greater than the second preset current threshold, return to execute the current reduction processing of the target unit according to the preset trigger angle; Step S303: If the current value is less than or equal to the second preset current threshold, stop the current reduction process on the target unit to obtain the third unit, and perform voltage reduction process on the third unit according to the preset voltage adjustment rate and the second preset voltage threshold to obtain a dual constant DC unit in single unit mode.

[0032] In step S301 of some embodiments, the controller analyzes the two sets of units in the dual constant DC unit that is operating in conduction mode to determine the target unit that needs to be locked; then, the controller performs a current reduction operation on the target unit according to a preset trigger angle, and monitors the current of the target unit in real time according to a preset current threshold, compares the monitored current value with the preset current threshold, and determines whether to stop the current reduction operation on the target unit.

[0033] In step S302 of some embodiments, if the monitored current value is greater than a preset current threshold, the controller continues to reduce the current of the target unit according to a preset firing angle until the monitored current value of the target unit is less than or equal to the preset current threshold; in this embodiment, the current threshold is set to zero.

[0034] In step S303 of some embodiments, if the monitored current value is less than or equal to a preset current threshold, the controller stops the current reduction operation on the target unit. At this time, the dual constant DC unit completes the mode switching, and only one constant DC unit operates to perform power transmission. The controller performs a voltage reduction operation on the target unit that has completed the current reduction operation to realize the lockout processing of the target unit. In this embodiment, the controller reduces the voltage of the target unit according to the preset voltage adjustment efficiency until the voltage of the target unit is less than or equal to the preset voltage threshold.

[0035] Please see Figure 4 In some embodiments, step S104 may include, but is not limited to, steps S401 to S404: Step S401: Analyze the dual constant straight unit to determine the target locking unit, and obtain the fourth unit by performing the unlocking operation on the target locking unit; Step S402: Perform power recovery on the fourth unit according to the preset power ramp rate, detect the current power value of the fourth unit, and compare the current power value with the preset power threshold. Step S403: If the current power value is greater than or equal to the preset power threshold, stop power recovery for the fourth unit and obtain the dual constant DC unit in loop power mode; Step S404: If the current power value is less than the preset power threshold, return to execute the power recovery of the fourth unit according to the preset power ramp rate.

[0036] In step S401 of some embodiments, the dual constant direct unit operating in single unit mode is analyzed to determine the locked constant direct unit and the healthy constant direct unit; the controller performs unlocking processing on the locked constant direct unit according to the preset trigger angle to obtain the conducting constant direct unit.

[0037] In step S402 of some embodiments, the controller restores the power of the conducting constant DC unit according to a preset power ramp rate, that is, it synchronously ramps up the unit current and power supply voltage of the conducting constant DC unit; the controller monitors the power of the constant DC unit in real time and compares the monitored power with a preset power threshold to determine whether the constant DC unit has completed mode switching; in this embodiment, the power threshold is determined based on the power value of the healthy constant DC unit, and the direction of power restoration of the conducting constant DC unit is opposite to the power transmission direction of the healthy constant DC unit, forming a local controllable circulating current.

[0038] In step S403 of some embodiments, if the detected power value is greater than or equal to a preset power threshold, the controller stops the power recovery operation of the constant DC unit and obtains a dual constant DC unit switched to loop power mode.

[0039] In step S404 of some embodiments, if the detected power value is less than a preset power threshold, the controller continues to restore the power of the constant DC unit according to a preset power ramp-up rate until the power of the constant DC unit is greater than or equal to the preset power threshold.

[0040] Please see Figure 5 In some embodiments, step S104 may also include, but is not limited to, steps S501 to S502: Step S501: Divide the dual constant DC units of the loop power mode according to the preset unit type to determine the constant power unit and the power inversion unit. Step S502: Perform power control on the constant power unit according to the preset power, and adjust the power reversal unit according to the power command and the preset ramp rate.

[0041] In step S501 of some embodiments, the controller analyzes and divides the dual constant DC single unit operating in loop power mode according to the preset unit type, determines the constant power unit and the power reversal unit, so as to reduce the power transmitted to the grid and realize power zero crossing and reversal. During the adjustment process, the minimum power transmission is maintained to achieve power reversal without power interruption and unit restart.

[0042] In step S502 of some embodiments, the controller divides the dual constant DC unit in loop power mode into a constant power unit and a power reversal unit. The controller adjusts the power of the constant power unit according to the minimum power limit of the constant DC unit to provide the necessary DC current support for the system with minimum power, thereby realizing the circulating current of the constant DC unit. The controller also continuously increases or decreases the power of the power reversal unit according to the preset power ramp rate and the issued power command, so that the total transmission power at the station level can be finely controlled and the direction can be switched near the zero point.

[0043] Please see Figure 6 In some embodiments, step S104 may also include, but is not limited to, steps S601 to S603: Step S601: Obtain the current power direction and compare it with the preset direction type to determine the current direction type; Step S602: If the current direction type is positive, the first unit in the dual constant direct unit is divided into a constant power unit, the second unit in the dual constant direct unit is divided into a power reversal unit, and the process returns to execute power control of the constant power unit according to the preset power, and power adjustment of the power reversal unit according to the power command and the preset ramp rate. Step S603: If the current direction type is reverse, the first unit in the dual constant direct unit is divided into a power inversion unit, the second unit in the dual constant direct unit is divided into a constant power unit, and the process returns to execute power control of the constant power unit according to the preset power, and power adjustment of the power inversion unit according to the power command and the preset ramp rate.

[0044] In step S601 of some embodiments, the controller obtains the transmission direction of the current station-level total power through a set measuring instrument, and compares the measured current transmission direction with a preset direction type to determine whether the current transmission direction is forward or reverse. In this embodiment, the power transmission of the system can be divided into region 1 and region 2. For example, in the power transmission system from power plant to substation, the power plant is divided into region 1 and the substation is divided into region 2. The power is defined as being sent from region 1 to region 2 as a preset direction. When the measured current power transmission direction is the same as the defined preset direction, the current power transmission direction is determined to be forward; otherwise, the current power transmission direction is determined to be reverse.

[0045] In step S602 of some embodiments, by comparison, it is determined that the current power transmission direction is positive. The controller defines the two sets of units in the dual constant DC unit as the first unit and the second unit, respectively. According to the preset unit type, the first unit in the dual constant DC unit is divided into a constant power unit and the second unit is divided into a power reversal unit. Then, according to the minimum power limit of the constant DC unit, the power of the constant power unit is adjusted to provide DC current support with minimum power, so as to avoid power interruption during the power reversal of the dual constant DC unit. According to the preset power ramp rate and the issued power command, the power of the power reversal unit is adjusted to increase or decrease, so that the total transmission power at the station level is reduced to near zero for fine control, and stable operation in the low power area. The power of the power reversal unit is further reduced so that the total transmission power at the station level smoothly crosses zero.

[0046] In step S603 of some embodiments, if the controller determines that the current power transmission direction is reversed by comparison, the controller will interchange the constant power unit and the power reversal unit in the dual constant DC unit. That is, the first unit in the dual constant DC unit will be assigned as the power reversal unit and the second unit will be assigned as the constant power unit. Then, the controller will adjust the power of the constant power unit according to the minimum power limit of the constant DC unit to provide DC current support with minimum power, so as to avoid power interruption in the dual constant DC unit during power reversal. The controller will also adjust the power of the power reversal unit according to the preset power ramp rate and the issued power command, so that the total transmission power at the station level is reduced to near zero for fine control, and the station will operate stably in the low power region. The power of the power reversal unit will be further reduced so that the total transmission power at the station level smoothly crosses zero.

[0047] The following is a detailed description and explanation of the solutions in the embodiments of the present invention, using specific application examples: Please refer to Figure 7 , Figure 7 This is a schematic diagram illustrating the structure of a power reversal control method based on dual constant DC units provided in this application, applied in a specific implementation. Two sets of line-converter DC transmission units are connected between two main power grids, forming a high-power back-to-back DC exchange channel for DC power transmission between the two regions' main grids. The DC-side parameters of the two sets of line-converter DC transmission units are identical: a rated DC voltage of ±160kV and a rated DC current of 2×3125 A (i.e., 3125 A per pole) per unit, enabling them to respectively complete DC power regulation under their respective power commands. The two sets of line-converter DC transmission units constitute a dual constant DC unit. The controller sets three operating modes for the dual constant DC unit and compares the total DC power at the station level of the dual constant DC unit with a preset power range. The mode switching of the dual constant DC unit is controlled according to the power range that the total DC power at the station level matches. The specific mode switching is as follows: Figure 8As shown; when both units in the dual constant DC unit are operating normally, the total DC power at the station level is monitored and compared with a preset power range. If the total DC power at the station level is greater than the upper limit of the preset power range, the controller forces a phase shift on the rectifier of one of the constant DC units according to a preset firing angle, thereby reducing the current of that unit and achieving mode switching. When the current of that unit decreases to zero, the controller stops triggering the rectifier and performs voltage reduction processing on that unit, thereby locking out that unit. When the voltage of that unit decreases to zero, the controller stops triggering the inverter of that unit. When the dual constant DC unit switches to single-unit mode, the total DC power at the station level can be controlled to be reduced to the minimum power value of the unit. The specific switching flowchart is shown below. Figure 9 As shown, where, Figure 9 (a) is a flowchart. Figure 9 (b) is a graph showing the current change during switching. Figure 9 (c) is a diagram showing the voltage change during switching. Figure 9 (d) shows the power change during switching; when the total DC power at the station level of the dual constant DC units is detected to be less than the lower limit of the power range, the controller re-triggers the rectifiers and / or inverters of the locked-in units according to the trigger angle, thereby unlocking the locked-in units; then, the unlocked units are restored to power according to the preset power ramp-up rate, and the unit is simultaneously boosted in voltage and current until the power reaches the given value; the controller switches the operating mode according to the power transmission direction and power command of the dual constant DC units, adjusting the magnitude and direction of the total DC power at the station level, such as... Figure 10 As shown, where, Figure 10 (a) is a flowchart. Figure 10 (b) is a graph showing the current change during switching. Figure 10 (c) is a diagram showing the voltage change during switching. Figure 10 (d) shows the power change during switching; by adjusting the operating mode of the dual constant DC unit to loop power mode, and the power values ​​of each constant DC unit, such as... Figure 11 As shown, the total DC power at the control station level is reduced to zero and smoothly reversed, and the control power is transmitted between the main power grids of the two regions.

[0048] The embodiments of this application include at least the following beneficial effects: This application provides a power reversal control method, system, electronic device, storage medium, and program product based on dual constant direct current units. This scheme obtains the current station-level total transmission power of the dual constant direct current units and compares the current station-level total transmission power with a preset power threshold range. If the current station-level total transmission power is greater than the upper limit of the preset power threshold range, the dual constant direct current units are controlled to switch to dual-unit mode, and power adjustment is performed on the current station-level transmission power in response to power commands. If the current station-level total transmission power is less than the lower limit of the preset power threshold range, the dual constant direct current units are controlled to switch to loop power mode, and power zero-crossing reversal is performed on the current station-level transmission power in response to power commands. If the current station-level total transmission power falls within the preset power threshold range, the dual constant direct current units are controlled to switch to single-unit mode, and power reduction is performed on the current station-level transmission power in response to power commands. By setting different modes of the dual constant direct current units and switching them based on the set power threshold range, smooth power zero crossing and improved power scheduling range are achieved, thereby improving the system's operational flexibility.

[0049] Please see Figure 12 This application also provides a power reversal control system based on dual constant DC units, which can implement the above method. The system includes: The acquisition module is used to acquire the current station-level total transmission power and compare the current station-level total transmission power with a preset power threshold range; The control module is used to control the dual constant direct unit to switch to dual unit mode if the current station-level total transmission power is greater than the upper limit of the preset power threshold range, and to adjust the current station-level total transmission power according to the preset power ramp rate in response to the power command. If the current station-level total transmission power is greater than or equal to the lower limit of the preset power threshold range and less than or equal to the upper limit of the preset power threshold range, the dual constant direct unit is controlled to switch to single unit mode, and in response to the power command, the current station-level total transmission power is reduced according to the preset power ramp rate. If the current station-level total transmission power is less than the lower limit of the preset power threshold range, the dual constant direct unit is controlled to switch to loop power mode, and in response to the power command, the current transmission power is reversed across zero according to the preset power ramp rate.

[0050] It is understood that the content of the above method embodiments is applicable to the present device embodiments. The specific functions implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0051] This application also provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the above-described method. This electronic device can be any smart terminal, including tablet computers, in-vehicle computers, etc.

[0052] It is understood that the content of the above method embodiments is applicable to this device embodiment. The specific functions implemented by this device embodiment are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0053] Please see Figure 13 , Figure 13 The hardware structure of an electronic device according to another embodiment is illustrated. The electronic device includes: The processor 1301 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this application. The memory 1302 can be implemented as a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 1302 can store the operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 1302 and is called and executed by the processor 1301 using the methods described in the embodiments of this application. The input / output interface 1303 is used to implement information input and output; The communication interface 1304 is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.). Bus 1305 transmits information between various components of the device (e.g., processor 1301, memory 1302, input / output interface 1303, and communication interface 1304); The processor 1301, memory 1302, input / output interface 1303 and communication interface 1304 are connected to each other within the device via bus 1305.

[0054] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method.

[0055] It is understood that the content of the above method embodiments is applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0056] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0057] It is understood that the content of the above method embodiments is applicable to the embodiments of this program product. The specific functions implemented by the embodiments of this program product are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.

[0058] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0059] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0060] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0061] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0062] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0063] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0064] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0065] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0066] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0067] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0068] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing programs, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0069] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A power reversal control method based on dual constant direct units, characterized in that, The method includes: Obtain the current station-level total transmission power and compare the current station-level total transmission power with a preset power threshold range; If the current station-level total transmission power is greater than the upper limit of the preset power threshold range, the dual constant direct unit is controlled to switch to dual unit mode, and in response to the power command, the current station-level total transmission power is adjusted according to the preset power ramp rate; If the current station-level total transmission power is greater than or equal to the lower limit of the preset power threshold range and less than or equal to the upper limit of the preset power threshold range, the dual constant direct unit is controlled to switch to single unit mode, and in response to the power command, the current station-level total transmission power is reduced according to the preset power ramp rate. If the current station-level total transmission power is less than the lower limit of the preset power threshold range, the dual constant direct unit is controlled to switch to loop power mode, and in response to the power command, the current transmission power is reversed across zero according to the preset power ramp rate.

2. The method according to claim 1, characterized in that, The control of switching the dual constant direct unit to dual unit mode specifically includes: The dual constant direct current units are tested to determine healthy constant direct current units and locked constant direct current units, and the healthy constant direct current units are tested to determine the target voltage polarity and unit firing angle; The locked constant direct unit is unlocked according to the unit trigger angle to obtain the first unit; and the first unit is boosted according to the target voltage polarity and the preset voltage adjustment rate, and the current voltage value of the first unit is compared with the preset voltage threshold. If the current voltage value is less than the preset voltage threshold, return to the step of boosting the first unit according to the target voltage polarity and the preset voltage adjustment rate; If the current voltage value is greater than or equal to the preset voltage threshold, the boost operation on the first unit is stopped, and the second unit is obtained. The second unit is then boosted according to the preset current adjustment rate and the preset current threshold to obtain a dual-unit mode dual constant DC unit.

3. The method according to claim 1, characterized in that, The control of switching the dual constant direct unit to single unit mode specifically includes: The dual constant current unit is analyzed to determine the target unit, and the current of the target unit is reduced according to the preset trigger angle. The current value of the target unit is then compared with the second preset current threshold. If the current value is greater than the second preset current threshold, return to the step of reducing the current of the target unit according to the preset trigger angle; If the current value is less than or equal to the second preset current threshold, the current reduction process for the target unit is stopped, and a third unit is obtained. The third unit is then subjected to voltage reduction processing according to the preset voltage adjustment rate and the second preset voltage threshold to obtain a dual constant DC unit in single-unit mode.

4. The method according to claim 1, characterized in that, The control of switching the dual constant DC unit to loop power mode specifically includes: The dual constant straight unit is analyzed to determine the target locking unit, and the fourth unit is obtained by performing a locking and unlocking operation on the target locking unit. The power of the fourth unit is restored according to the preset power ramp rate, and the current power value of the fourth unit is detected and compared with the preset power threshold. If the current power value is greater than or equal to the preset power threshold, power recovery for the fourth unit is stopped, resulting in a dual constant DC unit in loop power mode. If the current power value is less than the preset power threshold, return to the step of restoring the power of the fourth unit according to the preset power ramp rate.

5. The method according to claim 4, characterized in that, The loop power mode also includes: The loop power mode dual constant DC units are divided according to the preset unit type to determine the constant power unit and the power inversion unit. The constant power unit is controlled according to a preset power, and the power reversal unit is adjusted according to the power command and the preset ramp rate.

6. The method according to claim 5, characterized in that, The method further includes: Obtain the current power direction and compare it with a preset direction type to determine the current direction type; If the current direction type is positive, the first unit in the dual constant direct unit is divided into a constant power unit, the second unit in the dual constant direct unit is divided into a power reversal unit, and the process of controlling the power of the constant power unit according to the preset power and adjusting the power of the power reversal unit according to the power command and the preset ramp rate is returned to be executed. If the current direction type is reverse, the first unit in the dual constant direct unit is divided into a power inversion unit, the second unit in the dual constant direct unit is divided into a constant power unit, and the process returns to perform power control on the constant power unit according to the preset power, and power adjustment on the power inversion unit according to the power command and the preset ramp rate.

7. A power reversal control system based on dual constant direct units, characterized in that, The system includes: The acquisition module is used to acquire the current station-level total transmission power and compare the current station-level total transmission power with a preset power threshold range; The control module is used to control the dual constant direct unit to switch to dual unit mode if the current station-level total transmission power is greater than the upper limit of the preset power threshold range, and to adjust the current station-level total transmission power according to the preset power ramp rate in response to the power command. If the current station-level total transmission power is greater than or equal to the lower limit of the preset power threshold range and less than or equal to the upper limit of the preset power threshold range, the dual constant direct unit is controlled to switch to single unit mode, and in response to the power command, the current station-level total transmission power is reduced according to the preset power ramp rate. If the current station-level total transmission power is less than the lower limit of the preset power threshold range, the dual constant direct unit is controlled to switch to loop power mode, and in response to the power command, the current transmission power is reversed across zero according to the preset power ramp rate.

8. An electronic device, characterized in that, include: At least one processor; At least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor implements the method as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 6.

Images