Vehicle battery module including power conversion device and vehicle battery system formed based on the same

Abstract

The invention relates to a vehicle battery module including a power conversion device and a vehicle battery system formed based on the vehicle battery module. The vehicle battery module includes a battery, a first DC / DC converter, a second DC / DC converter, and an inverter. A vehicle battery system according to an exemplary embodiment of the present invention includes a plurality of vehicle battery modules, and includes a first direct current system output in which first direct current module outputs of a first direct current / direct current converter are connected in parallel with each other, a second direct current system output in which second direct current module outputs of a second direct current / direct current converter are connected in parallel with each other, and an alternating current system output. The second DC module outputs of the second DC / DC converters are connected in series with each other in the second DC system output, and the AC module outputs of the inverters are connected in series with each other in the AC system output.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the priority of Korean Patent Application No. 10-2023-0104426 filed on August 9, 2023, in the Korean Intellectual Property Office, and Korean Patent Application No. 10-2024-0093251 filed on July 15, 2024, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates to a vehicle battery module including a power conversion device and a vehicle battery system formed based on a plurality of vehicle battery modules. Background Art

[0004] Currently, increasing concerns about issues such as energy efficiency, environmental pollution, and depletion of fossil fuels have prompted efforts to develop environmentally friendly vehicles that can almost replace internal combustion engine vehicles.

[0005] Environmentally friendly vehicles may include battery electric vehicles (BEV) that use batteries as a power source, fuel cell electric vehicles (FCEV) that use fuel cells as a main power source, and hybrid electric vehicles (HEV) that use an engine and a motor as a driving device to drive the vehicle.

[0006] The above-mentioned environmentally friendly vehicles can be broadly referred to as electric vehicles (xEVs), and their common point is that they are both motor-driven vehicles and electrified vehicles, and travel by utilizing electricity from a high-voltage power source (e.g., a battery or a fuel cell) to drive the motor.

[0007] An electric vehicle may be equipped with a high-voltage battery that supplies power to a motor, and the high-voltage battery may be repeatedly charged and discharged during vehicle operation to supply power to power electronic components (e.g., motors, etc.) in the vehicle. The size and type of voltage required for each type of power electronic component may vary, and therefore, various types of power conversion devices may be required to convert the output voltage of the high-voltage battery. In this case, the power conversion device may need to convert the high voltage output from the high-voltage battery, and therefore a high-voltage power conversion device may be required, but its high price may increase production costs. Summary of the invention

[0008] One aspect of the present invention is to form an electric vehicle driving system based on high voltage operation according to the prior art to include a series or parallel combination of multiple battery modules operating at low voltage, thereby enabling the use of a power conversion device operating at low voltage.

[0009] Another aspect of the present invention is to form a battery system by connecting standardized battery modules to each other in series or in parallel, thereby outputting output voltages of various magnitudes according to purposes and responding to various specifications required by vehicle types.

[0010] Aspects of the present invention are not limited to the above-mentioned aspects, and those skilled in the art may clearly understand other aspects not described herein through the following description.

[0011] The present invention provides a vehicle battery module, a single-phase vehicle battery system and a three-phase vehicle battery system formed based on the vehicle battery module.

[0012] According to one aspect of the present invention, a vehicle battery module is provided, comprising: a battery, a first DC / DC converter, a second DC / DC converter and an inverter, wherein the battery is configured to output a battery voltage; the first DC / DC converter is configured to convert the battery voltage into a first DC module voltage lower than the battery voltage, and output the first DC module voltage; the second DC / DC converter is configured to convert the battery voltage into a second DC module voltage higher than the first DC module voltage, and output the second DC module voltage; the inverter is configured to convert the battery voltage into an AC module voltage, and output the AC module voltage.

[0013] According to another aspect of the present invention, a single-phase vehicle battery system is provided, which includes multiple vehicle battery modules, the vehicle battery modules including a first DC module output terminal configured to output a first DC module voltage according to an internal battery voltage, a second DC module output terminal configured to output a second DC module voltage, and an AC module output terminal configured to output an AC module voltage; the single-phase vehicle battery system includes a first DC system output terminal, a second DC system output terminal, and an AC system output terminal, in the first DC system output terminal, the first DC module output terminals respectively included in the multiple vehicle battery modules are connected in parallel with each other, in the second DC system output terminal, the second DC module output terminals respectively included in the multiple vehicle battery modules are connected in series with each other, and in the AC system output terminal, the AC module output terminals respectively included in the multiple vehicle battery modules are connected in series with each other.

[0014] According to another aspect of the present invention, a three-phase vehicle battery system is provided, which includes a plurality of single-phase vehicle battery systems, the single-phase vehicle battery systems are formed based on a plurality of vehicle battery modules, the vehicle battery modules include a first DC module output terminal configured to output a first DC module voltage according to an internal battery voltage, a second DC module output terminal configured to output a second DC module voltage, and an AC module output terminal configured to output an AC module voltage; the plurality of single-phase vehicle battery systems include a first DC system output terminal, a second DC system output terminal, and an AC system output terminal, in which the first DC module output terminals respectively included in the plurality of vehicle battery modules are connected in parallel with each other, in the second DC system output terminal, the second DC module output terminals respectively included in the plurality of vehicle battery modules are connected in series with each other, and in the AC system output terminal, the AC module output terminals respectively included in the plurality of vehicle battery modules are connected in series with each other. The AC system output terminals respectively included in the plurality of single-phase vehicle battery systems can be configured to output different AC system voltages having the same phase difference.

[0015] According to an exemplary embodiment of the present invention, a power conversion element operable at a low voltage uses a standardized battery module operating at a low voltage, thereby reducing production costs.

[0016] In addition, even if the voltage or specifications required for each type of vehicle are different, standardized battery modules can be combined with each other in series or parallel to meet various specifications. Standardized battery modules can be mass-produced, thereby reducing production costs.

[0017] In addition, standardized battery modules can be connected to each other in series or parallel to form a battery module system, thereby improving space utilization efficiency to reduce the overall volume, replacing each battery module for easy maintenance when a part of the battery module fails, and controlling the balance of each battery module to improve the overall energy efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other aspects, features and advantages of the present invention will be more clearly understood from the following detailed description presented in conjunction with the accompanying drawings, in which:

[0019] Figure 1 An electric vehicle drive system including a conventional high voltage battery pack is shown;

[0020] Figure 2 and Figure 3 shows a battery module according to an exemplary embodiment of the present invention;

[0021] Figure 4 is a schematic diagram showing a connection structure between a plurality of battery modules according to an exemplary embodiment of the present invention;

[0022] Figure 5 A single-phase battery system according to an exemplary embodiment of the present invention is shown;

[0023] Figure 6 is a schematic diagram showing a connection relationship between inverters in a three-phase battery system according to an exemplary embodiment of the present invention;

[0024] Figure 7 is a schematic diagram showing a connection relationship between first DC / DC converters in a three-phase battery system according to an exemplary embodiment of the present invention;

[0025] Figure 8 is a schematic diagram showing a connection relationship between second DC / DC converters in a three-phase battery system according to an exemplary embodiment of the present invention; and

[0026] Fig. 9 is a schematic diagram showing a structure of an inverter according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0027] Hereinafter, specific exemplary embodiments of the present invention will be described with reference to the accompanying drawings. The following detailed description is provided to help fully understand the methods, devices and / or systems described in this specification. However, the detailed description is only for illustrative purposes and the present invention is not limited thereto.

[0028] When describing the exemplary embodiments of the present invention, when it is determined that the detailed description of the known technology related to the present invention may unnecessarily obscure the main idea of ​​the present invention, its detailed description will be omitted. In addition, the terms to be described below are defined terms considering the functions in the present invention, which can change according to the intention or habit of the user or operator. Therefore, the definition of these terms should be based on the content in this specification. The terms used herein are only used to describe specific exemplary embodiments and do not limit the exemplary embodiments. The singular forms of "one", "an" and "the" used herein are intended to also include plural forms, unless the context clearly indicates otherwise. The term "and / or" used herein includes any one of the related enumerated items and any combination of any two or more. It should be further understood that when the terms "including" and / or "including" are used in this specification, it is indicated that there are the described features, values, steps, operations, elements, components and / or their combinations, but it is not excluded that there are or add one or more other features, values, steps, operations, elements, components, and / or their groups.

[0029] In addition, “module voltage” described below may refer to a voltage output from a battery module, and “system voltage” may refer to a voltage output from a battery system formed based on the battery module.

[0030] The battery module to be described below may include a vehicle battery module, and the battery system may include a single-phase vehicle battery system and a three-phase vehicle battery system.

[0031] Furthermore, the technology provided in the present invention can be used not only in vehicles but also in various devices to which battery modules and battery systems are applicable.

[0032] Figure 1 An electric vehicle drive system including a conventional high voltage battery pack is shown.

[0033] refer to Figure 1 The electric vehicle driving system 1 may include a conventional high-voltage battery pack 11 and various power conversion devices 12 .

[0034] In this case, the conventional high-voltage battery pack 11 may be formed by a series or parallel combination of a plurality of battery cells, and may not include a power conversion device. In addition, the conventional high-voltage battery pack 11 may output a single amplitude of high voltage (e.g., 480V to 806.4V). In addition, the power conversion device 12 may be disposed separately from the high-voltage battery pack 11 in space, and the high-voltage battery pack 11 and the power conversion device 12 may be connected to each other by a high-voltage cable.

[0035] An electric vehicle may have various functional electric loads, and the magnitude and type of voltage required by each electric load may vary, so various types of power conversion devices 12 may be required. However, an electric vehicle drive system 1 including a conventional high-voltage battery pack 11 may be based on a single high voltage, so a high-voltage power conversion device 12 may need to be used.

[0036] More specifically, the electric vehicle drive system 1 can convert the high voltage output from the conventional high-voltage battery pack 11 into a DC low voltage to provide a driving voltage to the low-voltage load R1 or charge the low-voltage battery. In this case, energy loss may occur in the process of converting power from high voltage to low voltage, which may reduce efficiency and may significantly reduce the voltage. Therefore, an additional transformer may be required. In addition, the electric vehicle drive system 1 can convert the voltage output from the conventional high-voltage battery pack 11 to provide a driving voltage to the high-voltage load R2, and can form a high-voltage three-phase AC power to drive the motor M. In this case, the inverter operating at high voltage can generally use SiC power semiconductors for high-voltage switching. However, the production of SiC power semiconductors is low relative to high demand, which makes it difficult to stabilize supply and demand, and the price may be high, which may increase production costs.

[0037] In addition, in the electric vehicle drive system 1, the high-voltage battery pack 11 and the power conversion device may be separated from each other, so that each component requires space, and it may be necessary to use a high-voltage cable to connect the high-voltage battery pack 11 and the power conversion device to each other, which may take up a lot of space. In addition, due to the high-voltage output of the high-voltage battery pack 11, the electric vehicle drive system 1 may generate a lot of heat, and a water cooling system may be required to control the generation of heat, which may take up a lot of space, and the water cooling system may be heavy.

[0038] According to the electric vehicle drive system 1 , specifications may differ depending on the vehicle type, and a battery system may need to be individually designed according to the specifications of the vehicle type, which may complicate the process and increase production costs.

[0039] A battery system according to an exemplary embodiment of the present invention described below may be formed by a series or parallel combination of a plurality of battery modules, and each battery module may include a low voltage battery, an inverter operating at a low voltage, a power conversion device such as a converter, and the like.

[0040] In other words, the battery system according to an exemplary embodiment of the present invention can be formed based on battery modules, and each battery module may include a power conversion device, so that electric energy can be stored / released and power conversion can be performed within the battery module. Accordingly, the battery module according to an exemplary embodiment of the present invention can convert DC power into AC power as needed, or convert the size of the battery power to output it. In addition, a high-voltage output can be formed by connecting the outputs of the battery modules in series with each other, or a high-current output can be formed by connecting the outputs of the battery modules in parallel with each other, and the voltage of each battery module can be monitored and balanced. Hereinafter, a battery module according to an exemplary embodiment of the present invention and a battery system including a battery module will be described in more detail.

[0041] Figure 2 A battery module according to an exemplary embodiment of the present invention is shown.

[0042] refer to Figure 2 , the battery module 10 according to the exemplary embodiment of the present invention may include a battery 110 , an inverter 120 , a first DC / DC converter 130 and a second DC / DC converter 140 .

[0043] The battery 110 may output a battery voltage and may charge or discharge electric energy. In addition, the battery voltage may form a basic voltage of the battery module 10 to provide an input voltage to the inverter 120 , the first DC / DC converter 130 , and the second DC / DC converter 140 .

[0044] In addition, the battery 110 may have an amplitude ratio reference Figure 1The conventional high voltage battery pack 11 described above has a low battery voltage. Accordingly, a power conversion element operable at a low voltage may be applied to the vehicle battery module 10 according to the exemplary embodiment of the present invention, thereby reducing production costs.

[0045] In addition, the battery module 10 according to the exemplary embodiment of the present invention can output voltages of various magnitudes and types according to the series or parallel combination of the battery modules 10, so that a single standardized battery module 10 can be applied to various specifications of vehicle types, thereby reducing production costs.

[0046] For example, when the battery voltage is set to 100 V, four battery modules 10 can be connected in series to form a battery system that outputs 400 V, and eight battery modules 10 can be connected in series to form a battery system that outputs 800 V. In addition, for example, when the battery voltage is set to 50 V, eight battery modules 10 can be connected in series to form a battery system that outputs 400 V, and sixteen battery modules 10 can be connected in series to form a battery system that outputs 800 V.

[0047] In addition, the battery modules 10 can be connected in series with each other, and a single-phase battery system that outputs a high-voltage AC voltage can be formed using an inverter output, and a plurality of single-phase battery systems can be used to output a three-phase AC voltage. In addition, the battery modules 10 can be combined in parallel with each other to form a battery system through which a high current flows.

[0048] The inverter 120 can convert the battery voltage into an AC module voltage and output the AC module voltage. In addition, the inverter 120 may include an input terminal and an output terminal. The inverter input terminal may be connected in parallel to the battery to receive the battery voltage, and the inverter output terminal may output the AC module voltage. Hereinafter, the inverter output terminal may be referred to as the AC module output terminal, which outputs the AC module voltage. In addition, the inverter 120 may be configured to supply AC power according to the AC module voltage to the AC load. In this case, the AC load may be a load (e.g., a motor) that uses an AC voltage as a driving voltage.

[0049] In addition, the first DC / DC converter 130 may convert the battery voltage into a first DC module voltage which is lower than the battery voltage, and may output the first DC module voltage.

[0050] In addition, the first DC module voltage can be set to a driving voltage of a low-voltage load. For example, the low-voltage load can be an electrical load such as various lights, radios, infotainment, etc. of an electric vehicle. In addition, the first DC module voltage can be set to 12V, 24V, or 48V, which is a driving voltage of a low-voltage load. However, the voltage amplitude mentioned in this article is only an example, and can be set to a voltage with various amplitudes according to the design.

[0051] In addition, the first DC / DC converter may include input terminals 130a and 130b and output terminals 130c and 130d. The input terminals 130a and 130b of the first DC / DC converter may be connected in parallel to the battery to receive the battery voltage, and the output terminals 130c and 130d of the first DC / DC converter may output the first DC module voltage. Hereinafter, the output terminals 130c and 130d of the first DC / DC converter may be referred to as first DC module output terminals, outputting the first DC module voltage.

[0052] In addition, the output terminals 130 c and 130 d of the first DC / DC converter may be directly connected to a low voltage load to provide a first DC module voltage.

[0053] In an exemplary embodiment, one output terminal 130d of the output terminals of the first DC / DC converter can be grounded, and the other output terminal 130c of the output terminals of the first DC / DC converter can be connected to a low voltage load to output the first DC module voltage. In another exemplary embodiment, both output terminals of the first DC / DC converter can be connected to both ends of the low voltage load to output the first DC module voltage.

[0054] In addition, the second DC / DC converter 140 may convert the battery voltage into a second DC module voltage and output the second DC module voltage. The second DC module voltage may be set to a value greater than the first DC module voltage output from the first DC / DC converter 130. In addition, the second DC module voltage may be lower than or equal to the battery voltage, or may be higher than the battery voltage.

[0055] In addition, the second DC module voltage output from the second DC / DC converter 140 can be connected in series to the second DC module voltage output from another battery module 10 to provide power to the high-voltage load. In other words, the second DC module voltage output from the second DC / DC converter 140 may not provide power to the high-voltage load as a single output, but may be connected in series to the second DC module voltage of another battery module 10 to provide power to the high-voltage load. The battery voltage included in the battery module 10 may be formed as a low voltage. In order to provide voltage to a high-voltage load such as an air-conditioning system, a plurality of battery modules 10 may be combined in series with each other to provide a high voltage. In other words, the output terminal of the second DC / DC converter may be connected in series to the output terminal of the second DC / DC converter of another battery module to form a high voltage, thereby providing power to the high-voltage load.

[0056] In addition, the second DC / DC converter may include input terminals 140a and 140b and output terminals 140c and 140d. The input terminals 140a and 140b of the second DC / DC converter may be connected in parallel to the battery 110 to receive the battery voltage, and the output terminals 140c and 140d of the second DC / DC converter may output the second DC module voltage. As used herein, the output terminals 140c and 140d of the second DC / DC converter may also be referred to as second DC module output terminals, outputting the second DC module voltage.

[0057] In addition, the output terminals 140c and 140d of the second DC / DC converter may be connected in series to the output terminals of the second DC / DC converter included in another battery module, or may be connected to a high voltage load. In this case, a specific connection structure with another battery module 10 will be described below.

[0058] In addition, the battery 110 may be connected in parallel to the input terminals 120a and 120b of the inverter, the input terminals 130a and 130b of the first DC / DC converter, and the input terminals 140a and 140b of the second DC / DC converter.

[0059] Figure 3 A battery module according to an exemplary embodiment of the present invention is shown.

[0060] refer to Figure 3 , the battery module 20 according to the exemplary embodiment of the present invention may include: a battery 210, an inverter 220, a first DC / DC converter 230, a second DC / DC converter 240, and a common capacitor 250. In addition, the common capacitor 250 may be connected to the battery 210 in parallel. Figure 3 The battery module 20 shown may include Figure 2 All components of the battery module 10 are shown, and the battery module 20 may further include a common capacitor 250 .

[0061] According to the battery module 20 of the exemplary embodiment of the present invention, a common capacitor can be shared without applying a capacitor to each inverter and each converter element. Accordingly, the volume can be reduced, and a low-voltage capacitor can be applied, thereby reducing production costs.

[0062] Figure 4 is a schematic diagram illustrating a connection structure between a plurality of battery modules according to an exemplary embodiment of the present invention.

[0063] refer to Figure 4 , the first battery module 10-1 and the second battery module 10-2 may include the same components and may have the same structure. Figure 2As described above, the first battery module 10-1 and the second battery module 10-2 may include: batteries 110-1 and 110-2, inverters 120-1 and 120-2, first DC / DC converters 130-1 and 130-2, and second DC / DC converters 140-1 and 140-2. Alternatively, the first battery module 10-1 and the second battery module 10-2 may further include as shown in reference Figure 3 The shared capacitor.

[0064] In addition, a plurality of battery modules may be connected to each other to form a battery system, and the connection relationship between each of the plurality of battery modules included in the battery system may be the same as Figure 4 The structures shown are the same.

[0065] More specifically, the output terminals 120-1c and 120-1d of the inverter included in the first battery module 10-1 can be connected in series to the output terminals 120-2c and 120-2d of the inverter included in the second battery module 10-2. In addition, when the inverter outputs the AC module voltage, the inverter 120-1 included in the first battery module and the inverter 120-2 included in the second battery module can be connected in series with each other to output an AC module voltage with an amplitude twice that of the AC module voltage. For example, when the AC module voltage is set to 100V, the two inverters 120-1 and 120-2 connected in series with each other can output an AC voltage of 200V. In this case, the amplitude of the AC voltage can refer to the maximum value, effective value, or average value of the AC voltage.

[0066] In addition, the output terminals 130-1c and 130-1d of the first DC / DC converter included in the first battery module 10-1 can be connected in parallel to the output terminals 130-2c and 130-2d of the first DC / DC converter included in the second battery module 10-2. In an exemplary embodiment, one of the output terminals 130-1d of the first DC / DC converter included in the first battery module 10-1 can be grounded, and one of the output terminals 130-2d of the first DC / DC converter included in the second battery module 10-2 can be grounded. In addition, the other terminal 130-1c of the output terminal of the first DC / DC converter included in the first battery module 10-1 can be connected in parallel to the other output terminal 130-2c of the output terminal of the first DC / DC converter included in the second battery module 10-2 to output the first DC module voltage. In addition, among the output terminals of the first DC / DC converter, the output terminals connected in parallel to each other can output the first DC module voltage, and the first DC module voltage can be used as a driving voltage to be connected to a low-voltage load to provide a voltage.

[0067] In addition, the output terminals 140-1c and 140-1d of the second DC / DC converter included in the first battery module 10-1 can be connected in series to the output terminals 140-2c and 140-2d of the second DC / DC converter included in the second battery module 10-2. More specifically, one output terminal 140-1d of the output terminals of the second DC / DC converter included in the first battery module 10-1 can be connected to the other output terminal 140-2c of the output terminals of the second DC / DC converter of the second battery module 10-2.

[0068] In addition, when the second DC / DC converter outputs the second DC module voltage, the second DC / DC converter 140-1 included in the first battery module and the second DC / DC converter 140-2 included in the second battery module can be connected in series with each other to output a second DC module voltage having an amplitude twice that of the second DC module voltage. For example, when the second DC module voltage is set to 100V, the two second DC / DC converters 140-1 and 140-2 can be connected in series with each other to output 200V.

[0069] That is, the first battery module 10 - 1 and the second battery module 10 - 2 may be connected to each other in series, the first DC / DC converters may be connected to each other in parallel, and the second DC / DC converters may be connected to each other in series.

[0070] Figure 5 A single-phase battery system according to an exemplary embodiment of the present invention is shown.

[0071] refer to Figure 5 According to an exemplary embodiment of the present invention, the single-phase battery system 100 may include a plurality of battery modules 10-1, 10-2, ..., 10-N. In addition, each of the plurality of battery modules 10-1, 10-2, ..., 10-N included in the single-phase battery system 100 may be connected to Figure 2 or Figure 3 The battery modules 10 and 20 shown in FIG. 1 are the same. In addition, the single-phase battery system 100 includes a plurality of battery modules 10-1, 10-2, ..., 10-N which may have Figure 4 The connection structure between the battery modules shown.

[0072] Return to reference Figure 2 , a battery module according to an exemplary embodiment of the present invention may include: first DC module output terminals 130c and 130d corresponding to the output terminal of the first DC / DC converter, second DC module output terminals 140c and 140d corresponding to the output terminal of the second DC / DC converter, and AC module output terminals 120c and 120d corresponding to the output terminal of the inverter.

[0073] In addition, reference Figure 5 , the single-phase battery system 100 according to the exemplary embodiment of the present invention may include: first DC system output terminals 130c and 130d, wherein the first DC module output terminals respectively included in the plurality of battery modules are connected in parallel with each other. In this case, the first DC system output terminals 130c and 130d may output a first DC system voltage, and the amplitude of the first DC system voltage may be the same as the amplitude of the first DC module voltage output from the output terminal of the first DC / DC converter.

[0074] In addition, the single-phase battery system 100 according to the exemplary embodiment of the present invention may include: second DC system output terminals 140-1c and 140-Nd, wherein the second DC module output terminals respectively included in the plurality of battery modules are connected in series with each other. Here, the second DC system output terminals 140-1c and 140-Nd may output a second DC system voltage, and the amplitude of the second DC system voltage may be an integer (N) times the amplitude of the second DC module voltage output from the output terminal of the second DC / DC converter.

[0075] In addition, the single-phase battery system 100 according to the exemplary embodiment of the present invention may include: AC system output terminals 120-1c and 120-Nd, wherein the AC module output terminals respectively included in the plurality of battery modules are connected in series with each other. In addition, the AC system output terminals 120-1c and 120-Nd can output an AC system voltage, and the amplitude of the AC system voltage can be an integer (N) times the amplitude of the AC module voltage output from the output terminal of the inverter. The AC system output terminal can provide AC power to an AC load, and can provide an input voltage for one phase of a three-phase AC voltage.

[0076] That is, in the single-phase battery system 100 , respective elements of a plurality of battery modules may be connected to each other in series or in parallel to provide various output voltages including a first DC system voltage, a second DC system voltage, and an AC system voltage.

[0077] In addition, the electric vehicle may include a low voltage load R1 operating at a low voltage, a high voltage load R2 operating at a high voltage, and an AC load (e.g., a motor M) operating at a high voltage three-phase AC voltage. In addition, the low voltage load may use the first DC system voltage as a driving voltage, the high voltage load may use the second DC system voltage as a driving voltage, and the AC load may use the AC system voltage as a driving voltage.

[0078] Figure 6 is a schematic diagram showing a connection relationship between inverters in a three-phase battery system 1000 according to an exemplary embodiment of the present invention. Figure 7is a schematic diagram showing a connection relationship between first DC / DC converters in a three-phase battery system according to an exemplary embodiment of the present invention. Figure 8 is a schematic diagram showing a connection relationship between second DC / DC converters in a three-phase battery system according to an exemplary embodiment of the present invention.

[0079] refer to Figures 6 to 8 According to an exemplary embodiment of the present invention, the three-phase battery system 1000 may include a plurality of single-phase battery systems 100 - 1 , 100 - 2 , and 100 - 3 , and each single-phase battery system may include a plurality of battery modules.

[0080] refer to Figure 6 According to an exemplary embodiment of the present invention, the three-phase battery system 1000 may include three single-phase battery systems 100-1, 100-2, and 100-3. In addition, the single-phase battery system may include an AC system output terminal, wherein the inverter output terminals are connected in series with each other. In addition, the AC system output terminals respectively included in the three single-phase battery systems may output different AC voltages having the same amplitude and the same phase difference.

[0081] For example, the AC system output terminals of the three single-phase battery systems can output different AC voltages with a phase difference of 120 degrees. Accordingly, the three-phase battery system can output a three-phase AC voltage, and the three-phase AC voltage can be used as a driving voltage to provide a driving voltage to the motor.

[0082] In addition, reference Figure 7 , each of the plurality of single-phase battery systems 100-1, 100-2, and 100-3 included in the three-phase battery system 1000 according to the exemplary embodiment of the present invention may include a first DC system output terminal, wherein the plurality of first DC / DC converters are connected in parallel to each other to output a first DC system voltage. In addition, the first DC system output terminals respectively included in the plurality of single-phase battery systems 100 may be connected in parallel to each other.

[0083] In other words, when the single-phase battery system 100 includes N first DC / DC converters, the 3×N first DC / DC converters included in the three-phase battery system 1000 can all be connected in parallel to each other to output a first AC module voltage or a first DC system voltage having the same amplitude as the first DC module voltage.

[0084] In addition, reference Figure 8, each of the multiple single-phase battery systems 100 included in the three-phase battery system 1000 according to the exemplary embodiment of the present invention may include a second DC system output terminal, wherein the multiple second DC / DC converters are connected in series to output a second DC system voltage. In addition, the second DC system output terminals respectively included in the multiple single-phase battery systems may be connected in parallel to each other. That is, in the single-phase battery system 100, the second DC module output terminals may be connected in series to form a second DC system output terminal. In the three-phase battery system 1000, the multiple second DC system output terminals may be connected in parallel to each other.

[0085] In addition, the three-phase battery system may further include a controller (not shown). The controller may control each battery module individually, and may control the inverter, the first DC / DC converter, and the second DC / DC converter included in each battery module individually. Accordingly, according to an exemplary embodiment of the present invention, balancing control may be performed on each power conversion element and each battery module, thereby improving energy efficiency.

[0086] Furthermore, when a problem occurs in one of the N battery modules, the controller may perform control to disconnect only the battery module in which the problem occurs, thereby ensuring the reliability of the entire system.

[0087] In addition, the controller can control each battery module individually. Accordingly, even when each battery module has different degrees of performance degradation, the degraded performance of each battery module can be actively controlled.

[0088] Fig. 9 is a schematic diagram showing a structure of an inverter according to an exemplary embodiment of the present invention.

[0089] refer to Fig. 9 , the inverter 120 may include a plurality of Si metal oxide semiconductor field effect transistor (MOSFET) elements 1201 , 1202 , 1203 , and 1204 , and may have an H-bridge single-phase inverter structure.

[0090] In an electric vehicle system according to the related art, SiC power semiconductors may be mainly applied, which may have high efficiency and fast switching speed, but may be expensive.

[0091] In addition, in some cases, electric vehicle systems according to the prior art may use insulated gate bipolar transistors (IGBTs) at low voltages. IGBTs may be relatively low in price, but may have a slow switching speed.

[0092] Si-MOSFET components can have fast switching speeds and can be relatively low in price. However, the performance of Si-MOSFET components under high voltages may deteriorate. Therefore, it may be difficult to apply Si-MOSFET components to high-voltage electric vehicle systems according to the prior art.

[0093] The battery module according to the exemplary embodiment of the present invention can be driven at low voltage, and the Si-MOSFET element can be applied to the inverter. Accordingly, the inverter included in the battery module according to the exemplary embodiment of the present invention can use multiple Si-MOSFET elements to reduce production costs and have a fast switching speed. Accordingly, fuel efficiency can be improved to increase the driving distance of the vehicle. As the driving distance increases, the battery capacity can be reduced to reduce production costs.

[0094] Furthermore, the inverter according to the exemplary embodiment of the present invention may have an H-bridge single-phase inverter structure and may maintain stability even at a high current.

[0095] also, Fig. 9 The case where an H-bridge circuit is formed using four Si-MOSFETs is shown as an example. However, an H-bridge circuit can be formed by connecting a plurality of Si-MOSFETs in parallel to each other, thereby realizing switching of a high current.

[0096] As described above, the present invention provides a technology that replaces the electric vehicle drive system according to the prior art that operates at high voltage by connecting standardized battery modules that operate at low voltage in series or in parallel with each other. The battery modules can be connected in series or in parallel with each other as needed to provide various outputs.

[0097] While exemplary embodiments have been shown and described above, it will be apparent to those skilled in the art that modifications and variations may be made without departing from the scope of the invention as defined in the appended claims.

Claims

1. A vehicle battery module, comprising: a battery configured to output a battery voltage; a first DC / DC converter configured to convert the battery voltage into a first DC module voltage lower than the battery voltage, and output the first DC module voltage; a second DC / DC converter configured to convert the battery voltage into a second DC module voltage higher than the first DC module voltage and output the second DC module voltage; and The inverter is configured to convert the battery voltage into an AC module voltage and output the AC module voltage.

2. The vehicle battery module according to claim 1, wherein: The battery is connected in parallel to an input terminal of the inverter, an input terminal of the first DC / DC converter, and an input terminal of the second DC / DC converter.

3. The vehicle battery module according to claim 1, wherein: The output terminal of the first DC / DC converter is connected in parallel to a first load that uses the first DC module voltage as a driving voltage.

4. The vehicle battery module according to claim 1, wherein: The second DC / DC converter is configured to supply power to a second load using an integral multiple of the second DC block voltage as a driving voltage.

5. The vehicle battery module according to claim 1, wherein: The inverter is configured to supply AC power according to the AC module voltage to the AC load.

6. A single-phase vehicle battery system comprising: A plurality of vehicle battery modules, the vehicle battery modules comprising: a first DC module output terminal configured to output a first DC module voltage according to an internal battery voltage, a second DC module output terminal configured to output a second DC module voltage, and an AC module output terminal configured to output an AC module voltage; a first DC system output terminal, wherein first DC module output terminals respectively included in a plurality of vehicle battery modules are connected in parallel with each other; a second DC system output terminal, wherein second DC module output terminals respectively included in a plurality of vehicle battery modules are connected in series with each other; and The AC system output terminal, wherein the AC module output terminals respectively included in the plurality of vehicle battery modules are connected in series with each other.

7. The single-phase vehicle battery system according to claim 6, wherein: Each of the plurality of vehicle battery modules comprises: a battery configured to output the internal battery voltage; A first DC / DC converter, comprising an output end of the first DC module; A second DC / DC converter, comprising the second DC module output terminal; and The inverter comprises the AC module output terminal.

8. The single-phase vehicle battery system according to claim 7, wherein: The battery is connected in parallel to an input terminal of the inverter, an input terminal of the first DC / DC converter, and an input terminal of the second DC / DC converter.

9. The single-phase vehicle battery system according to claim 6, wherein: The first DC system output terminal is configured to output a first DC module voltage and is connected to a first load that uses the first DC module voltage as a driving voltage.

10. The single-phase vehicle battery system according to claim 6, wherein: The second DC system output terminal is configured to output an integral multiple of the second DC module voltage and is connected to a second load that uses the integral multiple of the second DC module voltage as a driving voltage.

11. The single-phase vehicle battery system according to claim 6, wherein: The AC system output terminal is configured to output an integral multiple of the AC module voltage and is connected to an AC load that uses an integral multiple of the AC module voltage as a driving voltage.

12. A three-phase vehicle battery system comprising: A plurality of single-phase vehicle battery systems, the single-phase vehicle battery systems being formed based on a plurality of vehicle battery modules, the vehicle battery modules comprising a first DC module output terminal configured to output a first DC module voltage according to an internal battery voltage, a second DC module output terminal configured to output a second DC module voltage, and an AC module output terminal configured to output an AC module voltage; The plurality of single-phase vehicle battery systems each include: a first DC system output terminal, a second DC system output terminal, and an AC system output terminal, wherein the first DC module output terminals respectively included in the plurality of vehicle battery modules in the first DC system output terminal are connected in parallel with each other, the second DC module output terminals respectively included in the plurality of vehicle battery modules in the second DC system output terminal are connected in series with each other, and the AC module output terminals respectively included in the plurality of vehicle battery modules in the AC system output terminal are connected in series with each other; The AC system output terminals respectively included in the plurality of single-phase vehicle battery systems are configured to output different AC system voltages with the same phase difference.

13. The three-phase vehicle battery system according to claim 12, wherein: The first DC system output terminals respectively included in the plurality of single-phase vehicle battery systems are connected in parallel with each other to output a first DC module voltage.

14. The three-phase vehicle battery system according to claim 12, wherein: The second DC system output terminals respectively included in the plurality of single-phase vehicle battery systems are connected in parallel with each other to output an integral multiple of the second DC module voltage.

15. The three-phase vehicle battery system according to claim 12, wherein: Each of the plurality of vehicle battery modules includes: a battery configured to output a battery voltage; A first DC / DC converter, comprising an output end of the first DC module; A second DC / DC converter, comprising the second DC module output terminal; and The inverter comprises the AC module output terminal.

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