A wave-by-wave voltage limiting control method, system and storage medium for energy storage converter

Abstract

The present invention provides a wave-by-wave voltage limiting control method, system and storage medium for an energy storage converter. First, according to the first cycle information, the first voltage information is obtained; secondly, when it is determined that the first voltage information exceeds a preset first voltage threshold, the wave generating switch is disconnected; then, according to the first voltage information and the first voltage threshold, the first voltage difference information is obtained; finally, according to the second voltage information and the first voltage difference information, the first time information is determined for the timed closing of the wave generating switch; the present invention updates the state of the wave generating switch according to the set detection cycle, and when it detects that the voltage is too large, it cuts off the wave generating switch to achieve wave blocking, effectively controlling the voltage, preventing the voltage from being too large, and improving the operation safety of the energy storage converter.

Description

Technical Field

[0001] The present invention relates to the field of energy storage inverters, and more specifically, to a method, a system, and a storage medium for wave-by-wave voltage limiting control of an energy storage inverter. Background Art

[0002] With the rapid development of the energy storage industry, energy storage systems have been increasingly applied to improve energy utilization efficiency, reduce electricity costs, provide backup power supplies, and participate in auxiliary services in the power market. Among them, the energy storage inverter is used to complete the bidirectional conversion of energy between the battery and the power grid, that is, the bidirectional conversion between direct current and alternating current, and is a key device in the energy storage system. When a fault occurs in the energy storage system, in order to prevent the power module of the energy storage inverter from being damaged due to overload and threatening the safe operation of the entire energy storage system, currently, a wave-by-wave current limiting protection technology is usually adopted to reduce or disconnect the current of the power module to achieve shutdown protection.

[0003] However, when the power module charges the battery, if the relay on the battery side closes abnormally, that is, the relay that should be in the closed state suddenly disconnects and then quickly closes, it will cause the voltage on the power module side to be instantaneously too high, and the wave-by-wave current limiting protection technology cannot quickly reduce the above voltage. Therefore, there is an urgent need for a technology to quickly control the output voltage value of the wave-by-wave voltage limiting device of the energy storage inverter. Summary of the Invention

[0004] In view of the above problems, the purpose of the present invention is to provide a method, a system, and a storage medium for wave-by-wave voltage limiting control of an energy storage inverter, which can obtain the AC input voltage and DC output voltage of the wave-by-wave voltage limiting device of the energy storage inverter according to a preset acquisition and calculation method; then, when it is determined that voltage limiting protection is required based on the DC output voltage value, the disconnection time of the wave generation switch is obtained according to the AC input voltage value and the DC output voltage value to perform timed switching of the state of the wave generation switch.

[0005] The first aspect of the present invention provides a method for wave-by-wave voltage limiting control of an energy storage inverter, the method comprising: obtaining first cycle information;

[0006] Obtaining first voltage information according to the first cycle information;

[0007] Determining whether the first voltage information exceeds a preset first voltage threshold;

[0008] If so, disconnecting the wave generation switch;

[0009] Calculating a difference between the first voltage information and the first voltage threshold to obtain first voltage difference information;

[0010] Obtaining second voltage information according to the first cycle information;

[0011] Determine first time information according to the second voltage information and the first voltage difference information;

[0012] Close the wave - emitting switch according to the first time information.

[0013] In this solution, obtaining the first voltage information according to the first period information specifically includes:

[0014] Obtain second period information;

[0015] Obtain first acquisition voltage information according to the second period information;

[0016] Obtain a first voltage sequence according to the first acquisition voltage information according to a preset filtering strategy;

[0017] Obtain first voltage information according to the first voltage sequence according to a preset maximum - value extraction strategy.

[0018] In this solution, obtaining the second voltage information according to the first period information specifically includes:

[0019] Obtain third period information;

[0020] Obtain second acquisition voltage information according to the third period information;

[0021] Obtain a second voltage sequence according to the second acquisition voltage information according to a preset filtering strategy;

[0022] Obtain second voltage information according to the second voltage sequence according to a preset average - value calculation strategy.

[0023] This solution further includes:

[0024] The second period information is at least twice the first period information;

[0025] The third period information is at least twice the first period information.

[0026] In this solution, determining the first time information according to the second voltage information and the first voltage difference information specifically includes:

[0027] Obtain a second voltage threshold according to preset standard input voltage information;

[0028] Determine whether the second voltage information is lower than the second voltage threshold;

[0029] If so, set the first time information according to the first period information;

[0030] If not, according to the first voltage difference information, the first time information is obtained according to a preset time calculation relation.

[0031] This solution further includes:

[0032] Obtain the second time information;

[0033] Determine whether the second time information is greater than a preset time threshold;

[0034] If so, lower the first cycle information, the second cycle information or the third time cycle information.

[0035] In the second aspect of the present invention, a wave-by-wave voltage limiting control system for an energy storage converter is provided, including a wave-by-wave voltage limiting control method program for an energy storage converter. When the wave-by-wave voltage limiting control method program for the energy storage converter is executed by the processor, the following steps are implemented:

[0036] Obtain the first cycle information;

[0037] According to the first cycle information, obtain the first voltage information;

[0038] Determine whether the first voltage information exceeds a preset first voltage threshold;

[0039] If so, disconnect the wave generation switch;

[0040] Calculate the difference between the first voltage information and the first voltage threshold to obtain the first voltage difference information;

[0041] According to the first cycle information, obtain the second voltage information;

[0042] Determine the first time information according to the second voltage information and the first voltage difference information;

[0043] Close the wave generation switch according to the first time information.

[0044] In this solution, the obtaining of the first voltage information according to the first cycle information is specifically:

[0045] Obtain the second cycle information;

[0046] According to the second cycle information, obtain the first sampled voltage information;

[0047] According to the first sampled voltage information, obtain the first voltage sequence according to a preset filtering strategy;

[0048] According to the first voltage sequence, obtain the first voltage information according to a preset maximum value extraction strategy.

[0049] In this solution, obtaining the second voltage information according to the first cycle information specifically includes:

[0050] Obtaining the third cycle information;

[0051] Obtaining the second acquisition voltage information according to the third cycle information;

[0052] Obtaining the second voltage sequence according to the second acquisition voltage information according to a preset filtering strategy;

[0053] Obtaining the second voltage information according to the second voltage sequence according to a preset average value calculation strategy.

[0054] The third aspect of the present invention provides a computer-readable storage medium, which includes a program for the wave-by-wave voltage limiting control method of an energy storage converter. When the program for the wave-by-wave voltage limiting control method of the energy storage converter is executed by a processor, the steps of the wave-by-wave voltage limiting control method of the energy storage converter as described in any one of the above are realized.

[0055] The present invention provides a wave-by-wave voltage limiting control method, system and storage medium for an energy storage converter. First, obtaining the first voltage information according to the first cycle information; secondly, when it is judged that the first voltage information exceeds a preset first voltage threshold, disconnecting the wave generation switch; then, obtaining the first voltage difference information according to the first voltage information and the first voltage threshold; finally, determining the first time information according to the second voltage information and the first voltage difference information for the timed closing of the wave generation switch. The present invention updates the state of the wave generation switch according to the set detection period. When it is detected that the voltage is too high, the wave is blocked by disconnecting the wave generation switch, effectively controlling the voltage, preventing the voltage from being too high, and improving the operation safety of the energy storage converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope.

[0057] Figure 1 Shows a flowchart of a wave-by-wave voltage limiting control method for an energy storage converter of the present invention;

[0058] Figure 2 Shows a flowchart of calculating the first voltage information provided by an embodiment of the present invention;

[0059] Figure 3 Shows a flowchart of calculating the second voltage information provided by an embodiment of the present invention;

[0060] Figure 4The block diagram of a wave-by-wave voltage limiting control system for an energy storage converter according to the present invention is shown. Detailed implementation manners

[0061] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0062] Unless otherwise defined, all terms (including technical and scientific terms) used in the embodiments of the present invention have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless clearly defined in the embodiments of the present invention.

[0063] The "first", "second" and similar terms used in the embodiments of the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. Terms such as "a", "an" or "the" do not denote a quantity limitation either, but mean that there is at least one. Similarly, words such as "comprising" or "including" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. "Connection" or "coupling" and similar terms are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The steps before or after the methods in the embodiments of the present invention do not necessarily need to be carried out precisely in order. On the contrary, they can be carried out in reverse order or simultaneously. At the same time, other operations can also be added to these processes, or one or several steps can be removed from these processes.

[0064] In addition, the functional modules in each embodiment of the present invention can be integrated together to form an independent part, or each module can exist alone, or two or more modules can be integrated to form an independent part.

[0065] Figure 1 The flowchart of a wave-by-wave voltage limiting control method for an energy storage converter according to the present invention is shown.

[0066] As Figure 1 shown, the present invention discloses a wave-by-wave voltage limiting control method for an energy storage converter, and the method includes:

[0067] S102, obtaining first cycle information;

[0068] S104. Obtain first voltage information according to the first cycle information;

[0069] S106. Determine whether the first voltage information exceeds a preset first voltage threshold;

[0070] S108. If so, disconnect the wave - generating switch;

[0071] S110. Calculate the difference between the first voltage information and the first voltage threshold to obtain first voltage difference information;

[0072] S112. Obtain second voltage information according to the first cycle information;

[0073] S114. Determine first time information according to the second voltage information and the first voltage difference information;

[0074] S116. Close the wave - generating switch according to the first time information.

[0075] It should be noted that the wave - generating switch is the control switch tube in the power module of the energy storage converter device, such as IGBT or Sic MOSFFET, used to control the output voltage. As an implementation, when the wave - generating switch is disconnected, the output voltage can be reduced or the rising trend of the output voltage can be reduced. The first voltage information is the arithmetic value of the DC voltage output by the wave - by - wave voltage limiting device of the energy storage converter; the second voltage information is the arithmetic value of the AC voltage input by the wave - by - wave voltage limiting device of the energy storage converter; the first cycle information is the detection and adjustment cycle of the wave - by - wave voltage limiting device, that is, the acquisition cycle of the first voltage information and the second voltage information and the switching operation cycle of the wave - generating switch; the first time information is the time when the wave - generating switch is in the disconnected state within an adjustment cycle.

[0076] In this embodiment, according to the set first cycle information, the voltage detection and the wave - sending switch adjustment cycle are started. First, according to the set voltage acquisition strategy, the arithmetic value of the DC voltage output by the wave - by - wave voltage limiting device of the energy storage converter is obtained, that is, the first voltage information. Secondly, when it is determined that the first voltage information exceeds the preset first voltage threshold, it indicates that there is an abnormal situation that the output voltage of the wave - by - wave voltage limiting device of the energy storage converter is too high. At this time, the wave - sending switch is disconnected to reduce the output voltage or the rising trend of the output voltage. Then, the difference between the first voltage information and the first voltage threshold is calculated to obtain the first voltage difference information, which is used to represent the situation where the current output exceeds the normal range, that is, the amount of output voltage that needs to be adjusted. Finally, according to the arithmetic value of the AC voltage input to the wave - by - wave voltage limiting device of the energy storage converter and the first voltage difference information, according to the set strategy, the first time information is obtained, which is used to control the time when the wave - sending switch switches back to the closed state within the current adjustment cycle. The present invention updates the state of the wave - sending switch according to the set detection cycle. When the voltage is detected to be too large, the wave - sending switch is disconnected to achieve wave blocking, effectively controlling the voltage, preventing the voltage from being too large, and improving the operation safety of the energy storage converter.

[0077] Figure 2 The flowchart showing the calculation of the first voltage information provided by the embodiment of the present invention is shown.

[0078] According to the embodiment of the present invention, as Figure 2 shown, it further includes:

[0079] S202, obtaining the second cycle information;

[0080] S204, obtaining the first acquired voltage information according to the second cycle information;

[0081] S206, obtaining the first voltage sequence according to the first acquired voltage information according to the preset filtering strategy;

[0082] S208, obtaining the first voltage information according to the first voltage sequence according to the preset maximum value extraction strategy.

[0083] It should be noted that the first collected voltage information is the real-time collected value of the DC voltage output by the wave-by-wave voltage limiting device of the energy storage converter; the second cycle information is the collection cycle of the first collected voltage information. Within a voltage detection and wave generation switch adjustment cycle, the real-time collected value of the DC voltage output by the wave-by-wave voltage limiting device of the energy storage converter, that is, the first collected voltage information, is collected and recorded according to the second cycle information. Then, filtering processing is performed on several pieces of first collected voltage information within the same voltage detection and wave generation switch adjustment cycle, including but not limited to Butterworth low-pass filtering algorithm, Chebyshev low-pass filtering algorithm, Kalman filtering algorithm, etc., to obtain a first voltage sequence. Finally, according to a preset maximum value extraction strategy, first voltage information is obtained from the first voltage sequence; as an implementation manner, the maximum value extraction strategy is to compare and find a maximum value from the first voltage sequence as the output value; as another implementation manner, the maximum value extraction strategy is to find the first several maximum values from the first voltage sequence, for example, find the first 3 maximum values and perform an average operation to obtain the output value.

[0084] Figure 3 The flowchart showing the calculation of the second voltage information provided by the embodiment of the present invention is shown.

[0085] According to the embodiment of the present invention, as Figure 3 shown, it further includes:

[0086] S302, obtaining third cycle information;

[0087] S304, obtaining second collected voltage information according to the third cycle information;

[0088] S306, obtaining a second voltage sequence according to the second collected voltage information according to a preset filtering strategy;

[0089] S308, obtaining second voltage information according to the second voltage sequence according to a preset average value calculation strategy.

[0090] It should be noted that the second collected voltage information is the real-time collected value of the AC voltage input by the wave-by-wave voltage limiting device of the energy storage converter; the third cycle information is the collection cycle of the second collected voltage information. Within one voltage detection and wave generation switch adjustment cycle, the real-time collected value of the AC voltage input by the wave-by-wave voltage limiting device of the energy storage converter, that is, the second collected voltage information, is collected and recorded according to the third cycle information; wherein, in practical applications, the input alternating current is an alternating current in the form of a periodic sine wave. Then, filtering processing is performed on several second collected voltage information within the same voltage detection and wave generation switch adjustment cycle, including but not limited to Butterworth low-pass filtering algorithm, Chebyshev low-pass filtering algorithm, Kalman filtering algorithm, etc., to obtain a second voltage sequence. Finally, according to a preset average value calculation strategy, second voltage information is obtained from the second voltage sequence; as an implementation manner, the average value calculation strategy is to perform an arithmetic average operation on the second voltage sequence to obtain an output value; as another implementation manner, the average value calculation strategy is to sort the second voltage sequence and then extract several voltage values in the middle of several sorted queues for arithmetic average operation to obtain an output value.

[0091] According to an embodiment of the present invention, it further includes:

[0092] The second cycle information is at least twice the first cycle information;

[0093] The third cycle information is at least twice the first cycle information.

[0094] It should be noted that the magnitudes of the second cycle information and the third cycle information are both at least twice the first cycle information, so as to ensure that within the same voltage detection and wave generation switch adjustment cycle, at least two collections of the output DC voltage and the input AC voltage of the wave-by-wave voltage limiting device of the energy storage converter can be performed; in practical applications, to improve the sampling accuracy and the efficiency of binary operations, usually the magnitudes of the second cycle information and the third cycle information are both 8 times or 16 times the first cycle information. The second cycle information and the third cycle information can be the same value or different values. In practical applications, the same value method is usually used for timing.

[0095] According to an embodiment of the present invention, it further includes:

[0096] According to the preset standard input voltage information, a second voltage threshold is obtained;

[0097] Judge whether the second voltage information is lower than the second voltage threshold;

[0098] If so, set the first time information according to the first cycle information;

[0099] If not, according to the first voltage difference information, the first time information is obtained according to a preset time calculation relationship.

[0100] It should be noted that the standard input voltage information is the standard value of the input voltage of the wave-by-wave voltage limiting device of the energy storage converter. Taking 380V alternating current as an example below. The second voltage threshold is the effective value of the input voltage standard value, that is, 380V divided by 268.7V is obtained. When the second voltage information is lower than the second voltage threshold, it is determined that the real-time value of the input voltage is low. By turning off the wave generation switch, the rising trend of the output voltage can be reduced. Therefore, the time of the entire first cycle information is set to the time when the wave generation switch is off. When the second voltage information is not lower than the second voltage threshold, it is determined that the real-time value of the input voltage is high. By turning off the wave generation switch, the output voltage can be reduced. Therefore, according to the first voltage difference information, the first time information is obtained according to the set time calculation relationship; among them, as an implementation method, the time calculation relationship is a linear relationship.

[0101] According to an embodiment of the present invention, it further includes:

[0102] Obtain the second time information;

[0103] Judge whether the second time information is greater than a preset time threshold;

[0104] If so, lower the first time period information, the second time period information or the third time period information.

[0105] It should be noted that the second time information is the time when the wave generation switch remains closed after being switched back to the closed state. When the second time information is greater than the preset time threshold, it means that the output voltage of the wave-by-wave voltage limiting device of the energy storage converter is in a stable state that does not need to be adjusted for a relatively long time. At this time, by lowering the voltage detection and wave generation switch adjustment period, or lowering the voltage acquisition period, the computing power requirement can be reduced, so as to achieve the purpose of reducing power consumption.

[0106] It is worth mentioning that it further includes:

[0107] Obtain the record of the second time information;

[0108] Obtain the wave generation switch disconnection frequency information according to the record;

[0109] Judge whether the disconnection frequency information exceeds a preset frequency threshold;

[0110] If so, send a first warning instruction to the background.

[0111] It should be noted that in the second time information record, the recorded quantity and duration are used to represent the frequency of the wave - generation switch adjustment of the wave - by - wave voltage - limiting device of the energy storage converter, which is represented by the disconnection frequency information. When the disconnection frequency information exceeds the preset frequency threshold, it indicates that the operation of the wave - generation switch adjustment is too frequent, and it is determined that the relay on the battery side is abnormal. At this time, a first warning instruction is sent to the background to indicate that the relay on the battery side needs to be overhauled and maintained; thereby improving the overhaul and maintenance efficiency and the operation stability of the energy storage converter device.

[0112] It is worth mentioning that it also includes:

[0113] According to the first - cycle information and the first - voltage information, a first deviation - value information is obtained;

[0114] Judge whether the first deviation - value information exceeds a preset deviation threshold;

[0115] If so, increase the first - cycle information or adjust the weighting value of the time - calculation relational expression.

[0116] It should be noted that after calculating the difference between the first - voltage information of each first - cycle information and the standard output voltage value, the average value of the absolute value of the difference is calculated to obtain the first deviation - value information. The first deviation - value information is used to represent the stability of the output voltage. When the first deviation - value information exceeds the preset deviation threshold, it indicates that the output voltage has been in a state of large jitter for a long time; at this time, by increasing the first - cycle information, the voltage detection and the wave - generation switch adjustment frequency are increased; or by adjusting the slope in the linear relational expression of time calculation, the disconnection time of the wave - generation switch is adjusted; achieving the effect of improving the output adjustment accuracy and reducing the jitter amplitude, thereby improving the stability of the output voltage.

[0117] Figure 4 The block diagram of a wave - by - wave voltage - limiting control system of an energy storage converter according to the present invention is shown.

[0118] As Figure 4 shown, the present invention discloses a wave - by - wave voltage - limiting control system 4 of an energy storage converter, including a memory 41 and a processor 42. The memory includes a wave - by - wave voltage - limiting control method program for the energy storage converter. When the wave - by - wave voltage - limiting control method program for the energy storage converter is executed by the processor, the following steps are implemented: obtaining first - cycle information;

[0119] According to the first - cycle information, obtaining first - voltage information;

[0120] Judge whether the first - voltage information exceeds a preset first - voltage threshold;

[0121] If so, disconnect the wave - generation switch;

[0122] Calculate the difference between the first voltage information and the first voltage threshold to obtain first voltage difference information;

[0123] Obtain second voltage information according to the first period information;

[0124] Determine first time information according to the second voltage information and the first voltage difference information;

[0125] Close the wave - generating switch according to the first time information.

[0126] It should be noted that the wave - generating switch is the control switch tube in the power module of the energy storage converter device, such as IGBT or Sic MOSFFET, used to control the output voltage; as an implementation manner, when the wave - generating switch is disconnected, the output voltage can be reduced or the rising trend of the output voltage can be reduced. The first voltage information is the arithmetic value of the DC voltage output by the wave - by - wave voltage limiting device of the energy storage converter; the second voltage information is the arithmetic value of the AC voltage input to the wave - by - wave voltage limiting device of the energy storage converter; the first period information is the detection and adjustment period of the wave - by - wave voltage limiting device, that is, the acquisition period of the first voltage information and the second voltage information and the switching operation period of the wave - generating switch; the first time information is the time when the wave - generating switch is in the off state within one adjustment period.

[0127] In this embodiment, according to the set first period information, the voltage detection and the wave - generating switch adjustment period are started. First, according to the set voltage acquisition strategy, the arithmetic value of the DC voltage output by the wave - by - wave voltage limiting device of the energy storage converter is obtained, that is, the first voltage information. Secondly, when it is determined that the first voltage information exceeds the preset first voltage threshold, it indicates that there is an abnormal situation that the output voltage of the wave - by - wave voltage limiting device of the energy storage converter is too high. At this time, the wave - generating switch is disconnected to reduce the output voltage or the rising trend of the output voltage. Then, calculate the difference between the first voltage information and the first voltage threshold to obtain the first voltage difference information, which is used to represent the current situation where the output exceeds the normal range, that is, the amount of output voltage that needs to be adjusted. Finally, according to the arithmetic value of the AC voltage input to the wave - by - wave voltage limiting device of the energy storage converter and the first voltage difference information, according to the set strategy, the first time information is obtained, which is used to control the time when the wave - generating switch switches back to the closed state within the current adjustment period. The present invention updates the state of the wave - generating switch according to the set detection period. When the voltage is detected to be too large, the wave - generating switch is disconnected to achieve wave blocking, effectively controlling the voltage, preventing the voltage from being too large, and improving the operation safety of the energy storage converter.

[0128] According to an embodiment of the present invention, it further includes:

[0129] Obtain second period information;

[0130] Obtain first acquisition voltage information according to the second period information;

[0131] Obtain a first voltage sequence according to the first collected voltage information and a preset filtering strategy.

[0132] Obtain first voltage information according to the first voltage sequence and a preset maximum value extraction strategy.

[0133] It should be noted that the first collected voltage information is the real-time collected value of the DC voltage output by the wave-by-wave voltage limiting device of the energy storage converter; the second cycle information is the collection cycle of the first collected voltage information. Within a voltage detection and wave generation switch adjustment cycle, collect and record the real-time collected value of the DC voltage output by the wave-by-wave voltage limiting device of the energy storage converter according to the second cycle information, that is, the first collected voltage information. Then, perform filtering processing on several first collected voltage information within the same voltage detection and wave generation switch adjustment cycle, including but not limited to Butterworth low-pass filtering algorithm, Chebyshev low-pass filtering algorithm, Kalman filtering algorithm, etc., to obtain a first voltage sequence. Finally, obtain the first voltage information from the first voltage sequence according to a preset maximum value extraction strategy; as an implementation method, the maximum value extraction strategy is to compare and find a maximum value from the first voltage sequence as the output value; as another implementation method, the maximum value extraction strategy is to find the first several maximum values from the first voltage sequence. For example, find the first 3 maximum values and perform an average operation to obtain the output value.

[0134] According to an embodiment of the present invention, it further includes:

[0135] Obtain third cycle information;

[0136] Obtain second collected voltage information according to the third cycle information;

[0137] Obtain a second voltage sequence according to the second collected voltage information and a preset filtering strategy.

[0138] Obtain second voltage information according to the second voltage sequence and a preset average value calculation strategy.

[0139] It should be noted that the second collected voltage information is the real-time collected value of the AC voltage input by the wave-by-wave voltage limiting device of the energy storage converter; the third cycle information is the collection cycle of the second collected voltage information. Within one voltage detection and wave generation switch adjustment cycle, the real-time collected value of the AC voltage input by the wave-by-wave voltage limiting device of the energy storage converter, that is, the second collected voltage information, is collected and recorded according to the third cycle information; wherein, in practical applications, the input alternating current is an alternating current in the form of a periodic sine wave. Then, filtering processing is performed on several second collected voltage information within the same voltage detection and wave generation switch adjustment cycle, including but not limited to Butterworth low-pass filtering algorithm, Chebyshev low-pass filtering algorithm, Kalman filtering algorithm, etc., to obtain a second voltage sequence. Finally, according to a preset average value calculation strategy, second voltage information is obtained from the second voltage sequence; as an implementation manner, the average value calculation strategy is to perform an arithmetic average operation on the second voltage sequence to obtain an output value; as another implementation manner, the average value calculation strategy is to sort the second voltage sequence and then extract several voltage values in the middle of several sorted queues for arithmetic average operation to obtain an output value.

[0140] According to an embodiment of the present invention, it further includes:

[0141] The second cycle information is at least 2 times the first cycle information;

[0142] The third cycle information is at least 2 times the first cycle information.

[0143] It should be noted that the magnitudes of the second cycle information and the third cycle information are both at least 2 times the first cycle information, so as to ensure that within the same voltage detection and wave generation switch adjustment cycle, at least 2 times of collection of the output DC voltage and the input AC voltage of the wave-by-wave voltage limiting device of the energy storage converter can be performed; in practical applications, to improve the sampling accuracy and the efficiency of binary operations, usually the magnitudes of the second cycle information and the third cycle information are both 8 times or 16 times the first cycle information. The second cycle information and the third cycle information can be the same value or different values. In practical applications, the same value is usually used for timing.

[0144] According to an embodiment of the present invention, it further includes:

[0145] According to the preset standard input voltage information, a second voltage threshold is obtained;

[0146] It is judged whether the second voltage information is lower than the second voltage threshold;

[0147] If so, the first time information is set according to the first cycle information;

[0148] If not, then according to the first voltage difference information, the first time information is obtained according to a preset time calculation relationship.

[0149] It should be noted that the standard input voltage information is the standard value of the input voltage of the wave-by-wave voltage limiting device of the energy storage converter. Taking 380V alternating current as an example below. The second voltage threshold is the effective value of the input voltage standard value, that is, 380V divided by to get 268.7V. When the second voltage information is lower than the second voltage threshold, it is determined that the real-time value of the input voltage is low. By turning off the wave generation switch, the rising trend of the output voltage can be reduced. Therefore, the time of the entire first cycle information is set to the time when the wave generation switch is off. When the second voltage information is not lower than the second voltage threshold, it is determined that the real-time value of the input voltage is high. By turning off the wave generation switch, the output voltage can be reduced. Therefore, according to the first voltage difference information, the first time information is obtained according to the set time calculation relationship; among them, as an implementation manner, the time calculation relationship is a linear relationship.

[0150] According to an embodiment of the present invention, it further includes:

[0151] Obtain the second time information;

[0152] Judge whether the second time information is greater than a preset time threshold;

[0153] If so, then lower the first time period information, the second time period information or the third time period information.

[0154] It should be noted that the second time information is the time when the wave generation switch remains closed after being switched back to the closed state. When the second time information is greater than the preset time threshold, it means that the output voltage of the wave-by-wave voltage limiting device of the energy storage converter is in a stable state that does not need to be adjusted for a relatively long time. At this time, by lowering the voltage detection and wave generation switch adjustment period, or lowering the voltage acquisition period, the computing power requirement can be reduced, so as to achieve the purpose of reducing power consumption.

[0155] It is worth mentioning that it further includes:

[0156] Obtain the record of the second time information;

[0157] Obtain the wave generation switch disconnection frequency information according to the record;

[0158] Judge whether the disconnection frequency information exceeds a preset frequency threshold;

[0159] If so, send a first warning instruction to the background.

[0160] It should be noted that in the second time information record, the number of records and the length of time are used to represent the frequency of the wave-by-wave voltage limiting device of the energy storage converter to adjust the wave generation switch, which is represented by the disconnection frequency information. When the disconnection frequency information exceeds the preset frequency threshold, it means that the operation of adjusting the wave generation switch is too frequent, and it is determined that there is an abnormality in the relay on the battery side. At this time, a first warning instruction is sent to the background to indicate that the relay on the battery side needs to be repaired and maintained; thereby improving the repair and maintenance efficiency and the operation stability of the energy storage converter device.

[0161] It is worth mentioning that it also includes:

[0162] According to the first cycle information and the first voltage information, a first deviation value information is obtained;

[0163] Judge whether the first deviation value information exceeds the preset deviation threshold;

[0164] If so, increase the first cycle information or adjust the weighting value of the time calculation relationship formula.

[0165] It should be noted that after calculating the difference between the first voltage information of each first cycle information and the standard output voltage value, the average value of the absolute value of the difference is calculated to obtain the first deviation value information. The first deviation value information is used to represent the stability of the output voltage. When the first deviation value information is greater than the preset deviation threshold, it means that the output voltage has been in a state of large jitter for a long time; at this time, by increasing the first cycle information, the voltage detection and the wave generation switch adjustment frequency are improved; or by adjusting the slope in the linear relationship formula of time calculation, the disconnection time of the wave generation switch is adjusted; the effect of improving the output adjustment accuracy and reducing the jitter amplitude is achieved, thereby improving the stability of the output voltage.

[0166] The third aspect of the present invention provides a computer-readable storage medium, which includes a program for the wave-by-wave voltage limiting control method of an energy storage converter. When the program for the wave-by-wave voltage limiting control method of the energy storage converter is executed by a processor, the steps of the wave-by-wave voltage limiting control method of the energy storage converter as described in any one of the above are realized.

[0167] The present invention provides a method, a system and a storage medium for wave-by-wave voltage limiting control of an energy storage converter. First, first voltage information is obtained according to first cycle information. Secondly, when it is determined that the first voltage information exceeds a preset first voltage threshold, the wave generating switch is disconnected. Then, first voltage difference information is obtained according to the first voltage information and the first voltage threshold. Finally, first time information is determined according to second voltage information and the first voltage difference information for timed closing of the wave generating switch. The present invention updates the state of the wave generating switch according to a set detection period. When it is detected that the voltage is too high, wave blocking is achieved by disconnecting the wave generating switch, effectively controlling the voltage, preventing the voltage from being too high, and improving the operation safety of the energy storage converter.

[0168] If the above-mentioned function is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that makes a contribution to the prior art, or a part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks or optical discs that can store program codes.

[0169] The foregoing are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A wave-by-wave voltage limiting control method for an energy storage converter, applied to a wave-by-wave voltage limiting device for an energy storage converter, the device comprising a wave-generating switch, characterized in that: The method comprises: Get the first cycle information; Obtaining first voltage information according to the first cycle information; Determining whether the first voltage information exceeds a preset first voltage threshold; If yes, disconnect the wave switch; Calculating a difference between the first voltage information and the first voltage threshold to obtain first voltage difference information; Obtaining second voltage information according to the first cycle information; determining first time information according to the second voltage information and the first voltage difference information; According to the first time information, closing the wave-generating switch; The first voltage information is the arithmetic value of the DC voltage output by the wave-by-wave voltage limiting device of the energy storage converter; The second voltage information is the arithmetic value of the AC voltage input by the wave-by-wave voltage limiting device of the energy storage converter.

2. The wave-by-wave voltage limiting control method for an energy storage converter according to claim 1, characterized in that: The obtaining of the first voltage information according to the first cycle information is specifically: Get the second cycle information; According to the second cycle information, first collected voltage information is obtained; According to the first collected voltage information and a preset filtering strategy, a first voltage sequence is obtained; According to the first voltage sequence and a preset maximum value extraction strategy, first voltage information is obtained.

3. The wave-by-wave voltage limiting control method for an energy storage converter according to claim 1, characterized in that: The obtaining of the second voltage information according to the first cycle information is specifically: Get the third cycle information; Obtaining second collected voltage information according to the third cycle information; According to the second collected voltage information, a second voltage sequence is obtained according to a preset filtering strategy; According to the second voltage sequence and a preset average value calculation strategy, second voltage information is obtained.

4. A wave-by-wave voltage limiting control method for an energy storage converter according to claim 2 or 3, characterized in that: Also includes: The second cycle information is at least twice the first cycle information; The third cycle information is at least twice the first cycle information.

5. The wave-by-wave voltage limiting control method for an energy storage converter according to claim 1, characterized in that: The determining the first time information according to the second voltage information and the first voltage difference information is specifically: Obtaining a second voltage threshold according to preset standard input voltage information; Determining whether the second voltage information is lower than the second voltage threshold; If yes, setting the first time information according to the first period information; If not, the first time information is obtained according to the first voltage difference information and a preset time calculation formula.

6. The wave-by-wave voltage limiting control method for an energy storage converter according to claim 1, characterized in that: Also includes: Get second time information; Determining whether the second time information is greater than a preset time threshold; If so, the first period information, the second period information or the third period information is lowered.

7. A wave-by-wave voltage limiting control system for an energy storage converter, applied to a wave-by-wave voltage limiting device for an energy storage converter, the device comprising a wave-generating switch, characterized in that: The system includes a memory and a processor, wherein the memory includes a wave-by-wave voltage limiting control method program of an energy storage converter, and when the wave-by-wave voltage limiting control method program of the energy storage converter is executed by the processor, the following steps are implemented: Get the first cycle information; Obtaining first voltage information according to the first cycle information; Determining whether the first voltage information exceeds a preset first voltage threshold; If yes, disconnect the wave switch; Calculating a difference between the first voltage information and the first voltage threshold to obtain first voltage difference information; Obtaining second voltage information according to the first cycle information; determining first time information according to the second voltage information and the first voltage difference information; According to the first time information, closing the wave-generating switch; The first voltage information is the arithmetic value of the DC voltage output by the wave-by-wave voltage limiting device of the energy storage converter; The second voltage information is the arithmetic value of the AC voltage input by the wave-by-wave voltage limiting device of the energy storage converter.

8. The wave-by-wave voltage limiting control system of an energy storage converter according to claim 7, characterized in that: The obtaining of the first voltage information according to the first cycle information is specifically: Get the second cycle information; According to the second cycle information, first collected voltage information is obtained; According to the first collected voltage information and a preset filtering strategy, a first voltage sequence is obtained; According to the first voltage sequence and a preset maximum value extraction strategy, first voltage information is obtained.

9. The wave-by-wave voltage limiting control system of an energy storage converter according to claim 7, characterized in that: The obtaining of the second voltage information according to the first cycle information is specifically: Get the third cycle information; Obtaining second collected voltage information according to the third cycle information; According to the second collected voltage information, a second voltage sequence is obtained according to a preset filtering strategy; According to the second voltage sequence and a preset average value calculation strategy, second voltage information is obtained.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The computer-readable storage medium includes a wave-by-wave voltage limiting control method program for an energy storage inverter. When the wave-by-wave voltage limiting control method program for the energy storage inverter is executed by a processor, the steps of the wave-by-wave voltage limiting control method for the energy storage inverter as described in any one of claims 1 to 6 are implemented.

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