Power supply control device and power supply control method

Abstract

A power supply control device and a power supply control method are disclosed. The power supply control device according to the present invention includes a monitoring unit that monitors the first to nth drive times of first to nth power modules connected in parallel to each other for supplying DC power to electrical load equipment, and a main control unit that controls each of the first to nth power modules to be in a driven state or a non-driven state based on the first to nth drive times.

Description

Technical Field

[0001] The present invention relates to a control technique for suppressing variations in the lifespan among a plurality of power modules.

[0002] This application claims priority based on Korean Patent Application No. 10-2023-0162565 filed on November 21, 2023, and Korean Patent Application No. 10-2024-0160296 filed on November 12, 2024, and all the contents disclosed in the specifications and drawings of the said applications are incorporated into this application.

Background Art

[0003] A power supply device that supplies power to an electrical load (e.g., at least one battery charger) is configured in the form of an assembly in which a plurality of power modules are connected in parallel, in order to not only solve problems such as heat generation and the difficulty of organic response associated with fault diagnosis, but also supply power to the electrical load more stably.

[0004] Electric vehicles, ships, large-capacity energy storage systems (ESS), etc. mainly use power modules in such a form because the issues related to preventing safety accidents and providing stable power supply are relatively high.

[0005] In the case of a power supply device including a plurality of power modules, in step with the increase in the load amount, it not only has excellent scalability, but also has a higher space utilization rate compared to a single large-capacity power module, and can strongly respond to faults and errors. Moreover, even when an individual power module is being replaced, it has various advantages such as not having to cut off the power supply to the electrical load.

[0006] Normally, the power modules constituting the power supply device are electrically connected in parallel to the electrical load and are configured to supply power to the electrical load by performing relay control, etc.

[0007] Traditionally, power supply devices of this type were operated using a control method that adjusted the number of individual power modules driven according to the scale or magnitude of the power to be supplied; that is, a control method that gradually increased the number of power modules supplying power as the load increased.

[0008] In other words, conventional power supply devices do not operate using a high-precision control system that accurately monitors the operating time of individual power modules and uses this data to prevent variations in operating time between power modules.

[0009] Therefore, in the case of conventional power supply devices to which this method is applied, there may be no major problems for short-term use, but as the usage period is prolonged, there is a risk that the variation in operating time between power supply modules that are concentrated or unevenly driven and those that are not will widen.

[0010] When such variations become severe, it can have a significant impact on the driving performance and lifespan of individual power modules. This can lead to large discrepancies in characteristics and performance between power modules connected in parallel, potentially causing a degradation in the performance of the power supply device itself, such as a decrease in available output. [Overview of the project] [Problems that the invention aims to solve]

[0011] In view of the circumstances described above, the present invention was created to solve the aforementioned problems, and aims to provide a power supply control device and method that can improve the drive performance of the power supply device and extend its lifespan, as well as minimize time variations in the drive time between power modules by continuously and cyclically monitoring the drive time of each power module constituting the power supply device and incorporating the results of this monitoring into the drive control.

[0012] The technical problems that this invention aims to solve are not limited to those described above, and other problems not mentioned should be clearly understood by those skilled in the art from the description of the invention below. [Means for solving the problem]

[0013] A power supply control device according to one aspect of the present invention is for first to n power modules connected in parallel to each other for supplying DC power to electrical load equipment, where n is a natural number of 2 or more. The power supply control device includes a monitoring unit for monitoring the first to n drive times of the first to n power modules, and a main control unit for controlling each of the first to n power modules to be in an driven state or a non-driven state based on the first to n drive times.

[0014] The main control unit may be configured to perform statistical processing on the first to nth driving times and calculate the time variations of the first to nth power modules. The main control unit may be configured to select one of the first to nth power modules that is not driving when the time variation of any one of the first to nth power modules that is driving is greater than or equal to a reference variation. The main control unit may be configured to switch the selected power module from the non-driving state to the driving state.

[0015] The main control unit may be configured to output a first command signal for switching the selected power supply module from the non-driven state to the driven state. The main control unit may be configured to output a second command signal for switching the power supply module having a time variation greater than or equal to the reference variation from the driven state to the non-driven state once a deadband time has elapsed since the first command signal was output.

[0016] The main control unit may be configured to periodically or aperiodically update the first to nth time variations.

[0017] The main control unit may be configured to select one of the two or more power modules that are in a non-operating state, based on the operating time, idle time, or identification number of each of the two or more power modules that are in a non-operating state, when two or more of the first to nth power modules are in a non-operating state.

[0018] The main control unit may be configured to select one of the first to nth power supply modules that is in a non-driven state and switch the selected power supply module from the non-driven state to the driven state when the load rate of each power supply module in a driven state among the first to nth power supply modules exceeds the upper limit of the allowable load rate.

[0019] The system may further include an information sharing unit that generates a danger alarm when all of the first to nth power modules are in operation and the load rate of each of the first to nth power modules exceeds the upper limit of the allowable load rate.

[0020] The main control unit may be configured to switch one of the two or more power modules that are in the driven state from the driven state to the non-driven state when the load ratio of two or more power modules that are in the driven state among the first to nth power modules falls below the lower limit of the allowable load ratio.

[0021] A DC power supply system according to another aspect of the present invention includes the power supply control device.

[0022] A power supply control method according to another aspect of the present invention is provided for the first to nth power modules connected in parallel to each other for supplying DC power to an electrical load device. n is a natural number of 2 or more. The power supply control method includes a step of monitoring the driving times of the first to nth power modules, and a step of controlling each of the first to nth power modules to a driving state or a non-driving state based on the driving times of the first to nth power modules.

[0023] The step of controlling each of the first to nth power modules to a driving state or a non-driving state includes a step of performing statistical processing on the driving times of the first to nth power modules to calculate the first to nth time variations, and, when the time variation of any one of the power modules in the driving state among the first to nth power modules is equal to or greater than a reference variation, a step of selecting any one of the power modules in the non-driving state among the first to nth power modules, and a step of switching the selected power module from the non-driving state to the driving state.

[0024] In the step of selecting any one of the power modules in the non-driving state among the first to nth power modules, when two or more of the first to nth power modules are in the non-driving state, any one of the two or more power modules in the non-driving state can be selected based on the driving time, rest time, or identification number of each of the two or more power modules in the non-driving state.

[0025] The power supply control method may further include a step of selecting any one of the power modules in the non-driving state among the first to nth power modules, and a step of switching the selected power module from the non-driving state to the driving state when the load factor of each power module in the driving state among the first to nth power modules exceeds the upper limit of the allowable load factor.

[0026] The power supply control method may further include a step of switching any one of the two or more power modules in the driving state to the non-driving state when the load ratios of two or more power modules in the driving state among the first to nth power modules are below the lower limit of the allowable load ratio.

Effect of the Invention

[0027] According to the present invention, based on the result of cyclically or recursively performing statistical processing on the driving time of the power modules included in the power supply device, by applying the balancing of the driving time (operation time) of individual power modules in a time series, the variation in the lifespan among a plurality of power modules can be effectively suppressed.

[0028] Also, according to at least one embodiment of the present invention, by selecting the power modules that should be included in or excluded from the power supply to the electrical load using the criterion of prioritization based on the minimum driving time, even when the load required for the power supply target increases, the variation in the driving time among individual power modules can be suppressed as much as possible.

[0029] Furthermore, according to at least one embodiment of the present invention, by driving or stopping individual power modules so that the load ratio of the power module during driving falls within the range of the allowable load ratio, even when the power consumption in the electrical load fluctuates, unnecessary power loss can be suppressed as much as possible and high-efficiency operation can be enabled. This is because during driving at a load ratio within the range of the allowable load ratio, the input / output efficiency (power conversion efficiency) of the power module is maintained at a certain level or higher.

[0030] According to at least one embodiment of the present invention, by setting a bandtime interval between the signal system for stopping the operation of one power module and the signal system for starting the operation of the other power module, the clarity of the operation of the state switching process between the two power modules can be more reliably ensured.

[0031] Furthermore, according to at least one embodiment of the present invention, by selecting which power modules should be used to supply power to an electrical load and which should be excluded from supplying power to an electrical load, based not only on the operating time of each power module but also on the downtime of each power module, it is possible to further effectively reduce variations in performance and lifespan among power modules.

[0032] The drawings accompanying this specification illustrate preferred embodiments of the present invention and are intended to further illustrate the technical idea of ​​the invention along with the content of the invention; therefore, the present invention shall not be construed as being limited only to what is shown in the drawings. [Brief explanation of the drawing]

[0033] [Figure 1] This diagram schematically shows the configuration of a DC power supply system according to one embodiment of the present invention. [Figure 2] This diagram schematically shows an exemplary wiring relationship between the power supply control device, the power supply device, and the electrical equipment. [Figure 3] This is a block diagram schematically showing the configuration of a power supply control device according to one embodiment of the present invention. [Figure 4] Figure 3 is a block diagram that schematically shows the configuration of the main control unit. [Figure 5] This flowchart illustrates a process according to one embodiment of the present invention, which minimizes the time variation in operating time. [Figure 6] This flowchart explains the process of selecting a power supply module of interest using the relative relationships of the downtime periods. [Figure 7] This flowchart illustrates the process related to a subroutine that cyclically calculates the time variation of the operating time. [Figure 8] This flowchart exemplifies the process for ensuring that the load factor of individual power modules in operation remains within the allowable load factor range. [Figure 9] This flowchart exemplifies the process for ensuring that the load factor of individual power modules in operation remains within the allowable load factor range. [Figure 10] This diagram is used to illustrate an example of a process for reducing time variations in the operating times of multiple power supply modules. [Modes for carrying out the invention]

[0034] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and in the claims shall not be interpreted in their ordinary or dictionary sense, but rather in the sense and concept corresponding to the technical idea of ​​the present invention, in accordance with the principle that the inventor may appropriately define the concept of terms in order to best describe the invention.

[0035] Therefore, the embodiments described herein and the configurations shown in the drawings represent only preferred embodiments of the present invention and do not represent the entire technical concept of the invention. It should be understood that there are various equivalent and modified embodiments that can be substituted for these at the time of filing this application.

[0036] Furthermore, in describing the present invention, if it is deemed that a specific explanation of known technologies or functions related to the present invention would unnecessarily obscure the gist of the present invention, such explanation will be omitted.

[0037] Throughout the specification, when a part of it is said to "include" a component, this means, unless otherwise specified, that it may include other components rather than excluding them. Furthermore, terms such as "processor" in the specification mean a unit that processes at least one function or operation, which can be embodied in hardware, software, or a combination of hardware and software.

[0038] In addition to these, when a part of the specification is described as being "connected" to another part, this includes not only cases where the parts are "directly connected," but also cases where they are "indirectly connected" with other elements in between.

[0039] Figure 1 is a schematic diagram showing the configuration of a DC power supply system 10 according to one embodiment of the present invention, and Figure 2 is a schematic diagram showing an exemplary wiring relationship between the power supply control device 100, the power supply device 200, and the electrical load equipment 50.

[0040] Referring to Figure 1, the DC power supply system 10 includes electrical load equipment 50, a power supply control device 100, and a power supply device 200.

[0041] The power supply control device 100 is a device that monitors, manages, and controls the operating status of the power supply device 200 that supplies DC power to the electrical load equipment 50.

[0042] The electrical load device 50 is a load that uses electricity as its driving source and is supplied with power from the power supply device 200. The electrical load device 50 could be, for example, at least one battery charger / discharger installed in a battery manufacturing plant. Needless to say, the electrical load device 50 can be a conceptual term that collectively refers to various electrical devices, electrical equipment, electrical installations, etc.

[0043] The power supply device 200 may include the first to the nth power modules 210-1 to 210-n. Here, n means a natural number greater than or equal to 2. When i is a natural number less than or equal to n, the designation 210-i refers to the i-th power module among the first to the nth power modules 210-1 to 210-n. In the following explanation of the first to nth power modules 210-1 to 210-n, it should be noted that a power module may simply be assigned the designation 210.

[0044] As illustrated in Figure 2, each of the first to nth power modules 210-1 to 210-n is electrically connected in parallel with the power supply device 200, and power is supplied to the power supply device 200 by selectively controlling the on / off states of a first switching means S1 located on the positive line and a second switching means S2 located on the negative line by the power supply control device 100.

[0045] The configuration diagram shown in Figure 2 illustrates an example of the wiring relationship between the first to nth power modules 210-1 to 210-n and the electrical load equipment 50, for the first to nth power modules 210-1 to 210-n to supply DC power to the electrical load equipment 50. Therefore, it goes without saying that various designs and configurations different from those shown in Figure 2 can be adopted, as long as the first to nth power modules 210-1 to 210-n, connected in parallel with each other, can supply DC power to the electrical load equipment 50.

[0046] The power module 210 is typically composed of a DC power source. However, it is not limited to this, and power source conversion can be performed by employing various methods and associated circuit configurations, such as adding a DC converter, transformer, and smoothing circuit. Therefore, the power module 210 can also be composed of an AC power source.

[0047] Furthermore, the power module 210 may be composed of a secondary battery-based battery, and it goes without saying that, depending on the embodiment, it may be composed of various types and forms of power storage devices, power supply devices, etc.

[0048] The following section will provide a detailed explanation of the configuration of the power supply control device 100 and the processes performed by the power supply control device 100, based on the attached drawings and other materials.

[0049] Figure 3 is a schematic block diagram showing the configuration of a power supply control device 100 according to one embodiment of the present invention, Figure 4 is a schematic block diagram showing the configuration of the main control unit 130 shown in Figure 3, and Figure 5 is a flowchart illustrating a process according to one embodiment of the present invention that minimizes time variations in driving time.

[0050] Referring to Figure 3, the power supply control device 100 may be configured to include a measurement unit 110, a monitoring unit 120, a main control unit 130, a switching unit 140, an information sharing unit 150, and a history information storage unit 160.

[0051] The power supply control device 100 can be realized by applying various combinations of electronic elements and components such as storage means, arithmetic processing means, and input / output means (application-specific integrated circuits (ASICs), chipsets, logic circuits, registers, communication modems, microcontrollers (MCUs), etc.).

[0052] It should be understood that each component of the power supply control device 100 shown in Figure 3 may be a physically separated component, or it may be a functionally or logically separated component. The same applies to each component of the main control unit 130 shown in Figure 4.

[0053] In other words, each component shown in the above drawings corresponds to a logical component for effectively explaining the technical concept of the present invention. Therefore, even if each component is integrated or separated, as long as the function performed by the logical configuration of the present invention is realized, it is interpreted as being within the scope of the present invention. It goes without saying that components that perform the same or similar functions are interpreted as being within the scope of the present invention, regardless of whether their names are identical or not.

[0054] Furthermore, since the power supply control method according to the present invention can be implemented as a whole by a set of processes or algorithms related to data processing, handling, control, calculation, input / output, etc., it goes without saying that it can be implemented not only by combinations of components shown in Figure 3, etc., but also in the form of software installed and driven in a system, device, computer (or equivalent device), battery management system (BMS), module, or lower-level components thereof.

[0055] The monitoring unit 120 monitors the operating time of each of the first to nth power modules 210-1 to 210-n that constitute the power supply device 200 (see step S510 in Figure 5), and can output data regarding the operating time of each power module 210 to the main control unit 130.

[0056] In this specification, the operating time of the power module 210 may mean the total (cumulative) amount of time the power module 210 has been operating in the power state during the period from a specific point in the past to the present. The specific point in the past may be, for example, the first time the power module 210 was mounted on the DC power supply system 10 and used to supply DC power for the electrical load equipment 50.

[0057] Depending on the embodiment, the monitoring unit 120 may be electrically connected to each of the first to nth power supply modules 210-1 to 210-n, and may be configured to generate whether each power supply module 210 is driven and time information linked to the driving state, using the measurement results of the measurement unit 110 which measures electrical characteristic values ​​such as current output from each power supply module 210.

[0058] When data indicating the first to nth operating times, which are individually linked to the first to nth power modules 210-1 to 210-n, are input to the main control unit 130 via the monitoring unit 120, the main control unit 130 individually controls the operation of each of the first to nth power modules 210-1 to 210-n so as to minimize variations between the first to nth operating times (steps S550, S560). The ith operating time among the first to nth operating times is the operating time of the ith power module 210-i among the first to nth power modules 210-1 to 210-n.

[0059] Specifically, the main control unit 130 may include a reference information storage unit 131, a variation calculation unit 133, a selection unit 135, and a drive control unit 137, as shown in Figure 4.

[0060] The reference information storage unit 131 stores information indicating the reference variation (step S500). The reference variation may indicate the maximum limit of the time variation of the operating time that is permissible for the first to nth power supply modules 210-1 to 210-n.

[0061] The reference variation may be a predetermined fixed value. Alternatively, it goes without saying that the reference variation can be variably set by taking into account attribute information such as the power consumption of the electrical load equipment 50 connected to the power supply device 200, and specification information such as the discharge rate and discharge capacity of the power module 210.

[0062] The variation calculation unit 133 can perform statistical processing on the first to nth drive times input from the monitoring unit 120 to calculate the time variation for each of the first to nth drive times (see step S520 in Figure 5). The term "time variation" used in this specification may also be called "individual variation".

[0063] The process for calculating the aforementioned time variation corresponds to a separate subroutine that operates independently of the main process of the present invention, and can be configured to continuously update the time variation based on set generation criteria, such as periodic or non-periodic. Specific embodiments relating to this will be described later.

[0064] The variation calculation unit 133 performs statistical processing on the data related to the first to nth drive times from the monitoring unit 120 to determine the average value of the first to nth drive times (e.g., arithmetic mean, weighted mean, harmonic mean, etc.). The following formula 1 can be used to calculate the arithmetic mean of the first to nth drive times.

[0065]

number

[0066] The variation calculation unit 133 can determine the first to nth time variations of the first to nth power supply modules 210-1 to 210-n (step S520).

[0067] The following equation 2 can be used to determine the time variation of each of the first to nth power supply modules 210-1 to 210-n.

[0068]

number

[0069] In equations 1 and 2, T kσ is the operating time of the kth power supply module 210-k, n is the total number of power supply modules 210, A is the average value of the operating times of the 1st to nth power supply modules, and σ k is, T k The difference between this and A is, in other words, the time variation of the k-th power supply module 210-k.

[0070] The selection unit 135 can distinguish each of the first to nth power supply modules 210-1 to 210-n as either a "driven module" or a "non-driven module". A "driven module" refers to a power supply module 210 that is in a driven state, and a "non-driven module" refers to a power supply module 210 that is in a non-driven state.

[0071] Furthermore, when the selection unit 135 receives data on the time variations of the first to nth power supply modules 210-1 to 210-n from the variation calculation unit 133, it performs a process of comparing each of these time variations with a reference variation (see step S530 in Figure 5).

[0072] If the output value of step S530 is "YES", the selection unit 135 may select one of the first to nth power modules 210-1 to 210-n that is currently in a non-operating state (see step S540 in Figure 5). If two or more power modules are in a non-operating state, the selection unit 135 may select one of the two or more power modules.

[0073] In the following, for the sake of clarity and ease of explanation, power supply modules with time variations exceeding a baseline variation may be referred to as "target power supply modules." Furthermore, power supply modules that are in a non-operating state and possess the minimum operating time (or maximum idle time, or highest priority identification number) may be referred to as "power supply modules of interest." For reference, identification numbers 1 through n may be individually assigned to power supply modules 210-1 through n (210-n). The priority order among the identification numbers 1 through n may also be predetermined.

[0074] The drive control unit 137 can switch the power supply module 210 of interest from a non-driven state to a driven state by controlling the switching unit 140 and the like (see step S550 in Figure 5). The drive control unit 137 can also switch the target power supply module 210 from a driven state to a non-driven state (see step S560 in Figure 5).

[0075] In contrast, if there are no power supply modules 210 whose time variation exceeds the reference variation, then, with respect to the current time, it can be considered that there is no bias in the operating time among power supply modules 210-1 to 210-n, that is, that the time variation in the operating time among power supply modules 210-1 to 210-n is appropriately suppressed and in a balanced state.

[0076] Even in this case, the above-described drive time monitoring process (step S510) and variation calculation process (step S520) may be configured to be performed continuously and cyclically through the process of a subroutine, as will be described later with reference to Figure 7.

[0077] It goes without saying that the process shown in Figure 5 can be applied cyclically unless a pre-set termination condition is met (i.e., the value of step S570 is "NO"), such as forced termination, system downtime, or the occurrence of an emergency event.

[0078] Since the operating time of each individual power module 210 changes over time, the average and time variation of the operating times from the first to the nth also change dynamically.

[0079] The present invention can detect such time-series changes with respect to the current time and reflect this in the repeatedly and cyclically control the start of operation of the power module of interest and the stop of operation of the target power module. This makes it possible to ensure that the variation in the operating time of each of the first to n power modules 210-1 to 210-n included in the power supply unit 200 remains continuously within a reference variation, even if the overall usage of the power supply unit 200 increases over time.

[0080] The drive control unit 137 may output a first command signal to switch the power supply module of interest from a non-driven state to a driven state. The drive control unit 137 may be configured to output a second command signal to switch the target power supply module 210 from a driven state to a non-driven state after a deadband time has elapsed since the first command signal was output.

[0081] While this may not be the case when using sophisticated and high-precision hardware devices, when generating and outputting a digital signal system using analog signals, the signal value may be between 0 and 1 during a deadband section where the signal changes, even if only for a short time.

[0082] In other words, in the deadband section, with respect to the signal receiving side, a drive stop signal with a magnitude that decrements from 1 to 0 and a drive start signal that increments from 0 to 1 are received, which may cause the distinction between thresholds to become ambiguous and the distinction operation to become unclear.

[0083] As described above, when the system is configured such that the drive stop signal is output after a deadband time has elapsed, based on the time the drive start signal is output, the ambiguity of such a signaling system is effectively eliminated, making it possible to ensure even greater clarity in switching operations.

[0084] Various historical information, including information regarding the operating time of each of the power supply modules 210-1 to 210-n, information regarding the switching time between the operating state and the non-operating state, and information regarding which state (operating state or non-operating state) they are in, is stored in the historical information storage unit 160 and can be used in subsequent processes and application processes.

[0085] Figure 6 is a flowchart illustrating the process of selecting the power supply module 210 of interest using the relative relationship of the downtime.

[0086] As described above, the selection unit 135 selects one of the power supply modules that is in a non-operating state (e.g., 210-2) if the time variation of the power supply module is greater than or equal to the reference variation (for example, if 210-1 exists (step S530) and the output value is "YES") (step S540). If two or more power supply modules are in a non-operating state, the power supply module selected in step S540 (e.g., 210-2) may be the power supply module with the shortest operating time.

[0087] Specifically, if there are multiple power supply modules that are not in operation, the selection unit 135 performs a process (see step S600 in Figure 6) to compare the operating times of each of these power supply modules (e.g., 210-2, 210-3, 210-4) with one another, and can select a candidate power supply module with the shortest operating time among the multiple power supply modules (step S610).

[0088] The selection unit 135 determines whether there is a single candidate power supply module among two or more power supply modules (for example, 210-2, 210-3, 210-4) that are in a non-operating state.

[0089] If, among multiple non-driven modules (for example, 210-2, 210-3, 210-4), there is only one candidate power supply module that corresponds to the shortest driving time, the selection unit 135 may select that single candidate power supply module as the power supply module of interest (step S630).

[0090] In contrast, if there are multiple candidate power supply modules with the shortest operating time, the selection unit 135 compares the rest times of the multiple candidate power supply modules with respect to the current time (step S640), and may select one candidate power supply module with the longest rest time as the power supply module of interest (step S650). In step S650, instead of the longest rest time, one candidate power supply module with the highest priority identification number may be selected as the power supply module of interest (step S650).

[0091] The idle time of a power module 210 in a non-operating state may refer to the elapsed time since the most recent time the power module 210 switched from an operating state to a non-operating state. The power module of interest refers to the power module that will take over supplying DC power to the electrical load equipment 50 in place of the target power module that will soon be deactivated.

[0092] In this embodiment of the present invention, by appropriately adjusting and distributing the operating time and rest time, the phenomenon of continuous accumulation and concentration of operating time can be reduced to the greatest extent possible. This makes it possible to further optimize and stabilize the driving performance of each power supply module 210.

[0093] Needless to say, depending on the embodiment, pre-set prioritization information (for example, criteria such as manufacturing date, service life, and degree of degradation) can be used in the process of selecting one of several candidate power supply modules as the power supply module of interest.

[0094] Figure 7 is a flowchart illustrating the process related to a subroutine that cyclically calculates the time variation of the operating time.

[0095] As described above, the operating times of the first to nth power modules 210-1 to 210-n, the average of the operating times of the first to nth modules, and the time variations of the operating times of the first to nth modules all change dynamically over time.

[0096] Therefore, by cyclically reflecting such changes in the process of the present invention described above and updating the relevant data, it is possible to prevent excessive variation in the operating time for each power module 210 throughout the entire service life.

[0097] For this purpose, the monitoring unit 120 can monitor the first to nth operating times of the first to nth power supply modules 210-1 to 210-n (step S700). The monitoring unit 120 can output information or data indicating the first to nth operating times to the variation calculation unit 133.

[0098] The monitoring process (step S700) can be performed based on a predetermined period using a clock setting or the like, and it goes without saying that it can also be performed based on a non-periodic period in which events such as the start or stop of operation of the power supply module 210 occur.

[0099] The variation calculation unit 133 can store data relating to the first to nth drive times (step S710). As a result, the first to nth drive times are updated periodically or aperiodicly.

[0100] Depending on the embodiment, the data for the first to nth operating times entered at the current time may be saved by replacing the previously saved data for the first to nth operating times. Needless to say, in order to improve the efficiency of statistical calculations and application processes, it is also possible to save the data for the first to nth operating times in the form of historical data in which the previous data and the current data are linked to each other.

[0101] Next, the variation calculation unit 133 performs statistical processing on the first to nth driving times to determine the average value (step S720), and determines the first to nth time variations, which represent the individual differences of the first to nth driving times from the average value (step S730). The variation calculation unit 133 stores the first to nth time variations determined in step S730 (step S740). Here, the statistical processing can be arithmetic mean calculation, weighted mean calculation, etc., as described above.

[0102] After the first to nth time variations have been saved, if an information request signal is input from the selection unit 135 (the value in step S740 is "YES"), the variation calculation unit 133 outputs data showing the most recently saved first to nth time variations, relative to the current time point, to the selection unit 135 (step S760).

[0103] When pre-set termination conditions are not met (the output value of step S770 is "NO"), the above-described process for calculating and outputting time variation is preferably configured to be performed cyclically and continuously in conjunction with the periodic or non-periodic monitoring results of the monitoring unit 120.

[0104] The following describes the process for ensuring that the load factor of the power modules 210-1 to 210-n that are in operation remains within the range of the allowable load factor, based on Figures 8 and 9.

[0105] The reference information storage unit 131 can store the allowable load rates of the first to nth power supply modules 210-1 to 210-n (step S800).

[0106] In the present invention, the allowable load factor can indicate the upper and lower limits of the load factor at which the input / output efficiency of the power module 210 exceeds a certain level.

[0107] The upper limit of the allowable load factor may be a criterion that limits the maximum load (power) that the power module 210 is responsible for. The upper limit of the allowable load factor means the ratio of the maximum allowable output to the maximum available output. The lower limit of the allowable load factor means the ratio of the minimum allowable output to the maximum available output. At least one of the upper or lower limits of the allowable load factor may be predetermined, in which case step S800 can be omitted from the method shown in Figure 8.

[0108] If the load factor of the power supply module 210 falls below the lower limit of the allowable load factor or exceeds the upper limit of the allowable load factor, the input / output efficiency of the power supply module 210 may fall below a certain level. Therefore, a process is necessary to adjust the load factor of the power supply module 210 while it is in operation between the upper and lower limits of the allowable load factor. The range between the lower and upper limits of the allowable load factor may be referred to as the "allowable load factor range."

[0109] The current load factor of power module 210 may represent the ratio of the current output of power module 210 to the maximum available output. The allowable load factor may be common to the first to nth power modules 210-1 to 210-n.

[0110] For example, if the maximum available power of a power module 210 is 20kW and the upper limit of its allowable load factor is set to 70%, then the power supplied by each power module 210 in operation must be controlled so as not to exceed 14kW.

[0111] To improve the efficiency of explanation and understanding, it is assumed that the maximum available output of the first to nth power modules 210-1 to 210-n are all the same.

[0112] The monitoring unit 120 described above, in conjunction with the measurement unit 110, can monitor the load factor of the power modules that are in operation among the first to nth power modules 210-1 to 210-n (step S810). Since the current load factor of a power module that is not in operation must be 0, there is no need to monitor the load factor of each power module that is not in operation. In other words, in this specification, the process related to the load factor of a power module may be based on the premise that the power module is in operation.

[0113] The selection unit 135 distinguishes each of the first to nth power supply modules 210-1 to 210-n as either a power supply module in an operating state or a power supply module in an inoperable state.

[0114] Furthermore, the selection unit 135 can determine whether the load factor of the power supply module in operation exceeds the upper limit of the allowable load factor (step S820). If the value in step S820 is "yes", the process can proceed to step S830.

[0115] The selection unit 135 determines whether at least one of the first to nth power modules 210-1 to 210-n is in a non-operating state (step S830). If, as a result of the determination in step S830, at least one power module is in a non-operating state (i.e., in a dormant state), the selection unit 135 may select the power module with the shortest operating time among the non-operating modules (step S840). The power module selected in step S840 may be the same power module as the power module of interest described above.

[0116] The drive control unit 137 can switch the power supply module 210 selected in step S840 from a non-driven state to a driven state (step S860).

[0117] For example, if the allowable load factor is 70%, the maximum available output of the power module 210 is 20kW, and the four power modules are currently operating (i.e., running), and the power consumption of the electrical load device 50 is 50kW, then each power module 210 will supply 50kW / 4 = 12.5kW of power. Based on this example, the current load factor of each power module 210 is 62.5% (12.5kW / 20kW), which does not exceed the allowable load factor (70%), so it can be said that there is no need to add any more power modules 210.

[0118] In this case, the process of the present invention described above can be applied to monitor the operating time of each of the four power modules and, if an imbalance in operating time occurs, to stop the operation of the target power module 210 and start the operation of the power module 210 of interest.

[0119] In contrast, when the power consumption of the electrical load equipment 50 rises to 72kW while all four power modules 210 are running, each of the four power modules 210 will equally supply 18kW of power. Therefore, the current load factor of the power modules 210 (90%) will exceed the allowable load factor (70%) (the output value in step S820 is "YES").

[0120] In this case, the selection unit 135 may select one power supply module that is in a non-driven state and has the shortest drive time (step S840). Next, the drive control unit 137 may switch the power supply module selected in step S840 from a non-driven state to a driven state (step S860).

[0121] Through the process described above, if the power modules selected from the first to nth power modules 210-1 to 210-n are further switched to the driven state, the number of power modules in the driven state will increase from 4 to 5. As a result, each of the 5 power modules will supply 72kW / 5 = 14.4kW of power to the electrical load equipment 50. In this case, the load factor of each of the 5 power modules decreases from 90% to 14.4kW / 20kW × 100% = 72%, but still exceeds the allowable load factor of 70% (the output value in step S820 is "YES"). Therefore, step S840 shown in Figure 8, namely the process of further selecting the power module with the shortest driving time from among the remaining non-driven power modules (multiple modules are possible), may be performed again.

[0122] Through this process, as the number of power modules operating in the drive state increases from 5 to 6, each of the 6 power modules will supply 12.0 kW (72 kW / 6 units) of power, and the load factor of each of the 6 power modules will switch to a stable load state below the upper limit of the allowable load factor, which is 70%.

[0123] On the other hand, if the lower limit of the allowable load factor for power module 210, which has a maximum available power of 20kW, is set to 40%, then the power supplied by power module 210 needs to be controlled to exceed 8kW.

[0124] If the value in step S820 is "No", the method shown in Figure 9 may be performed.

[0125] Referring to Figure 9, the selection unit 135 can determine whether two or more power modules are in operation (step S900). If the value in step S900 is "yes", the process can proceed to step S910. If the value in step S900 is "no", it may indicate that only one power module is in operation.

[0126] The selection unit 135 can determine whether the load factor of the power supply module in operation is below the lower limit of the allowable load factor (step S910). If the value in step S900 or step S910 is "no", the process can proceed to step S870 in Figure 8.

[0127] If the value in step S910 is "yes", the selection unit 135 may select one of the two or more power supply modules that are in operation (step S920). In step S920, the power supply module with the longest possible operating time may be selected.

[0128] The drive control unit 137 can switch the power supply module selected in step S920 from a driven state to a non-driven state (step S930).

[0129] Suppose the lower limit of the allowable load factor is 40%, the maximum available output of the power module 210 is 20kW, all four power modules are currently operating (i.e., in a running state), and the power consumption of the electrical load device 50 is 50kW. Then, the four running power modules 210 should be supplying 12.5kW of power evenly to the electrical load device 50. The current load factor of each power module 210 is 12.5kW / 20kW × 100% = 62.5%, which exceeds the lower limit of the allowable load factor (40%). Therefore, it can be said that there is no need to select a power module from the four running power modules 210 to be stopped. In this case, the above-described process can be executed to monitor the operating time of each of the four running power modules and, if an imbalance in operating time occurs, to stop the operation of the target power module and start the operation of the power module of interest.

[0130] In contrast, when the power consumption of the electrical load equipment 50 decreases from 50kW to 30kW while the four power modules 210 are running, each of the four power modules 210 will equally supply 7.5kW of power, and the load factor of the four power modules 210 will decrease from 62.5% to 37.5%.

[0131] As a result, in step S910, it is determined that the current load factor of the power supply module in the driving state, 37.5%, falls below the lower limit of the allowable load factor, 40%. In this case, the selection unit 135 may select one of the four power supply modules that has the longest driving time (step S920). Next, the drive control unit 137 may switch the power supply module with the longest driving time from the driving state to the non-driving state (step S930).

[0132] Once step S930 is performed, the number of power modules in operation decreases from four to three. As a result, each of the three power modules will equally supply 30kW / 3=10kW of power to the electrical load equipment 50. In this case, the load factor of each of the three power modules increases from 37.5% to 50%, adjusting it to fall between the lower limit of 40% and the upper limit of 70% of the allowable load factor.

[0133] If, despite the number of power modules in operation decreasing from four to three, the load factor of the power module 210 in operation remains below the lower limit of the allowable load factor, steps S920 and S930 shown in Figure 9 may be performed again.

[0134] As described above, a target power module and / or power module of interest is selected from the first to nth power modules 210-1 to 210-n based on at least one of the operating time, rest time, and load factor of each of the first to nth power modules 210-1 to 210-n. By cyclically applying a process that controls each selected power module to switch between an operating state and a non-operating state, it becomes possible to operate the first to nth power modules 210-1 to 210-n more stably by preventing the operating time (drive time) and / or load factor of individual power modules from becoming excessively high or low compared to other power modules.

[0135] In relation to the above-mentioned implementation configuration, if there are no power modules among the first to nth power modules 210-1 to 210-n that are currently in a non-operating state, that is, if all of the first to nth power modules 210-1 to 210-n are operating, it means that the load factor of each individual power module 210 is exceeding the allowable load factor and power is being supplied accordingly.

[0136] Thus, even though the first to nth power modules 210-1 to 210-n are all in operation, if the load rate exceeds the upper limit of the allowable load rate (the output value in step S820 is "NO"), the information sharing unit 150 generates alarm information and can transmit the generated alarm information to a user terminal, the vehicle's information system, a control server, etc. (step S850). The alarm information may be intended to notify the user or others that an overload risk has occurred. Performing step S850 makes it possible to effectively guide subsequent measures for the risk situation where the output value in step S830 is "NO".

[0137] It goes without saying that the process shown in Figure 8 is also cyclically applicable unless a pre-set termination condition is met, such as forced termination, system downtime, or the occurrence of an emergency event (i.e., the value in step S870 is "NO").

[0138] Figure 10 is a diagram used to illustrate an example of a process for reducing time variations in operating times among multiple power supply modules.

[0139] Figure 10 assumes that the power supply unit 200 includes six power modules 210-1 to 210-6. Figure 10 schematically shows an example of the transition between the driven state and the non-driven state of each of the six power modules 210-1 to 210-6 as time progresses during the operation of the DC power supply system 10. For reference, in Figure 10, the symbol A indicates the driven state, and the symbol R indicates the idle state (non-driven state).

[0140] Furthermore, the six time intervals P1 to P6 may be distinguished based on the point in time when a switching event occurs between an operating state and a non-operating state in at least one of the first to sixth power modules 210-1 to 210-6. In explaining Figure 10, at the start of the first time interval P1, the operating time of all power modules 210-1 to 210-6 is t ac And we assume that they are all the same.

[0141] In the first time interval P1, it is illustrated that only the first power module 210-1 of the first to sixth power modules 210-1 to 210-6 is in an operational state, while the remaining five power modules 210-2 to 210-6 are in an inactive state.

[0142] In the first time interval P1, when the load factor of the first power module 210-1 exceeds the allowable load factor, the power module of interest is selected from the remaining five power modules 210-2 to 210-6. As a result, the second power module 210-2, which was in a non-operating state in the first time interval P1, is switched to an operating state, ending the first time interval P1 and starting the second time interval P2.

[0143] During the second time interval P2, the first power module 210-1 and the second power module 210-2 supply DC power to the electrical load equipment 50. That is, throughout the second time interval P2, the two power modules 210-1 and 210-2 operate in an driven state, while the remaining power modules 210-3, 210-4, 210-5, and 210-6 remain in an inactive state.

[0144] In the second time interval P2, the time variation of the operating times of the two power modules 210-1 and 210-2 may reach the reference variation, and in addition, the load factor of the two power modules 210-1 and 210-2 may exceed the upper limit of the allowable load factor. As a result, it is necessary to select at least one power module (the power module of interest) from the remaining power modules 210-3, 210-4, 210-5, and 210-6 to operate in the driven state, in place of at least one of the two power modules 210-1 and 210-2. Figure 10 illustrates that the third to fifth power modules 210-3, 210-4, and 210-5 have each been selected as the power module of interest. As a result, the first and second power modules 210-1 and 210-2 are switched to a non-driven state, and the third to fifth power modules 210-3, 210-4, and 210-5 are switched to a driven state, ending the second time interval P2 and starting the third time interval P3.

[0145] During the third time interval P3, the sixth power module 210-6 remains in a non-operated state.

[0146] In the third time interval P3, when the load factor of the third to fifth power modules 210-3, 210-4, and 210-5 exceeds the allowable load factor, at least one of the remaining three power modules 210-1, 210-2, and 210-6 is selected as the power module of interest. The sixth power module 210-6, which has been continuously inactive throughout the first to third time intervals P1 to P3, should have the shortest operating time and the longest rest time, so the sixth power module 210-6 is switched to the operating state. This ends the third time interval P3, and the following fourth time interval P4 begins.

[0147] During the fourth time interval P4, the third to sixth power modules 210-3 to 210-6 will operate in a driven state, while the first and second power modules 210-1 and 210-2 will remain in a deactivated state.

[0148] In the fourth time interval P4, if the load factor of each of the four power modules 210-3 to 210-6 exceeds the upper limit of the allowable load factor, at least one of the first and second power modules 210-1 and 210-2, which are in a non-driven state, is switched to a driven state. Figure 10 illustrates that the second power module 210-2 has been selected as the power module of interest. As a result, the fourth time interval P4 ends and the fifth time interval P5 begins.

[0149] In the fifth time interval P5, the second to sixth power modules 210-2 to 210-6 are all in a driven state, while only the first power module 210-1 is in a deactivated state.

[0150] In the fifth time interval P5, if the load factor of each of the five power modules 210-2 to 210-6 exceeds the upper limit of the allowable load factor, even the first power module 210-1, which is in a non-operating state, is switched to an operating state. As a result, the fifth time interval P5 ends and the sixth time interval P6 begins.

[0151] The changes in operating time and time variation of the first to sixth power modules 210-1 to 210-6 during the period from the start of the first time interval P1 to the end of the sixth time interval P6 are summarized in Table 1 below. Table 1 is summarized assuming that the length of each of the first to sixth time intervals P1 to P6 is Δt and is the same for all of them.

[0152] [Table 1]

[0153] Table 1 summarizes the maximum operating time, the power supply module with the maximum operating time, the minimum operating time, the power supply module with the minimum operating time, and the maximum time variation (i.e., the difference between the maximum operating time and the minimum operating time) for each of the time intervals P1-P6.

[0154] As can be clearly seen from Table 1, when the control method according to the present invention described above is applied, even if the power consumption of the electrical load equipment 50 changes over time, the maximum time variation of the operating time between power modules 210-1 to 210-n can be continuously kept below the reference variation (e.g., 2Δt).

[0155] Although the present invention has been described above with limited embodiments and drawings, the present invention is not limited in any way thereto, and it goes without saying that it can be implemented by persons with ordinary skill in the art to which the present invention belongs with various modifications and variations within the equivalent scope of the technical idea of ​​the present invention and the appended claims.

[0156] The accompanying drawings and other illustrations for the purpose of describing the present invention and illustrating its embodiments may be shown in a somewhat exaggerated form to emphasize or highlight the technical content of the present invention. However, considering the above-mentioned content and the illustrated matters, it is understood that a wide variety of modified application forms can be adopted by someone at the level of an ordinary engineer in this art.

[0157] Furthermore, in describing the present invention, it is clear that terms such as first, second, upper, lower, or top and bottom are merely instrumental conceptual terms used to relatively distinguish each component (element) from one another, and are not terms used to indicate a specific order, priority, etc., nor are they terms used to physically distinguish each component (element) based on an absolute standard.

Claims

1. In a power supply control device for first to n power modules connected in parallel to each other for supplying DC power to electrical load equipment, A monitoring unit that monitors the first to nth operating times of the first to nth power supply modules, A main control unit that controls each of the first to n power supply modules to be in an driven state or a non-driven state based on the first to n driving times, A power supply control device that includes a function where n is a natural number greater than or equal to 2.

2. The main control unit is, Statistical processing is performed on the first to nth driving times to calculate the time variations from the first to nth, If the time variation of any one of the first to n power modules that is in operation exceeds the reference variation, then one of the first to n power modules that is not in operation is selected. The power supply control device according to claim 1, which switches the selected power supply module from the non-operated state to the operated state.

3. The main control unit is, A first command signal is output to switch the selected power supply module from the non-operated state to the operated state. The power supply control device according to claim 2, wherein, once a deadband time has elapsed since the first command signal was output, a second command signal is output to switch the power supply module having a time variation greater than or equal to the reference variation from the driven state to the non-driven state.

4. The main control unit is, The power supply control device according to claim 2, wherein the first to nth time variations are updated periodically or aperiodically.

5. The main control unit is, The power supply control device according to claim 2, wherein when two or more of the first to nth power supply modules are in the non-operating state, one of the two or more power supply modules in the non-operating state is selected based on the operating time, idle time, or identification number of each of the two or more power supply modules in the non-operating state.

6. The main control unit is, If the load factor of any of the first to nth power supply modules that are in operation exceeds the upper limit of the allowable load factor, select one of the first to nth power supply modules that is not in operation. The power supply control device according to claim 1, which switches the selected power supply module from the non-operated state to the operated state.

7. The power supply control device according to claim 1, further comprising an information sharing unit that generates danger alarm information when all of the first to nth power supply modules are in operation and the load rate of each of the first to nth power supply modules exceeds the upper limit of the allowable load rate.

8. The main control unit is, The power supply control device according to claim 1, wherein when the load rate of two or more power supply modules that are in the driven state among the first to nth power supply modules falls below the lower limit of the allowable load rate, one of the two or more power supply modules that are in the driven state is switched from the driven state to the non-driven state.

9. A DC power supply system comprising a power supply control device according to any one of claims 1 to 8.

10. A power supply control method for first to n power modules connected in parallel to each other for supplying DC power to electrical load equipment, The steps include monitoring the operating times of the first to nth power supply modules, A step of controlling each of the first to n power supply modules to be in an driven state or a non-driven state based on the first to nth driving times, A power supply control method that includes n, where n is a natural number greater than or equal to 2.

11. The step of controlling each of the first to nth power supply modules to be in an driven state or a non-driven state is: The steps include performing statistical processing on the first to nth driving times to calculate the time variations of the first to nth, The steps include: selecting one of the first to n power modules that is not in operation if the time variation of any one of the first to n power modules that is in operation exceeds a reference variation; The steps include switching the selected power supply module from the non-operated state to the operated state, The power supply control method according to claim 10, including the method described in claim 10.

12. In the step of selecting one of the first to nth power supply modules that is in a non-operating state, The power supply control method according to claim 11, wherein when two or more of the first to nth power supply modules are in the non-operating state, one of the two or more power supply modules in the non-operating state is selected based on the operating time, idle time, or identification number of each of the two or more power supply modules in the non-operating state.

13. The steps include selecting one of the power modules that is not in operation among the first to n power modules if the load factor of each power module that is in operation among the first to n power modules exceeds the upper limit of the allowable load factor, The steps include switching the selected power supply module from the non-operated state to the operated state, The power supply control method according to claim 10, further comprising:

14. The power supply control method according to claim 10, further comprising the step of switching one of the two or more power supply modules that are in a driven state from the driven state to the non-driven state when the load rate of two or more power supply modules that are in a driven state among the first to nth power supply modules falls below the lower limit of the allowable load rate.

Images