Power control device

Abstract

A power control device (2) comprises a reactor unit (7) and a sensor unit (9). The reactor unit (7) and the sensor unit (9) are disposed adjacently in an X direction. A reactor element (40) has a core (45) and a coil (46). The sensor unit (9) has a current measurement unit (30). The shortest distance between the current measurement unit (30) and a first core (41) is distance D1. The shortest distance between the current measurement unit (30) and a second core (42) is distance D2. In terms of adjacency, the distance (D2) between the current measurement unit (30) and the second core (42) at which the magnetic permeability is not the minimum is shorter than the distance (D1) between the current measurement unit (30) and the first core (41), which is also referred to as another core. By satisfying this distance relationship, the influence of the first core (41) on the current measurement unit (30) is suppressed.

Description

Power Control Device CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2023-134229 filed in Japan on August 21, 2023, and the contents of the original application are incorporated by reference in their entirety.

[0002] TECHNICAL FIELD The disclosure herein relates to a power control device.

[0003] Patent Document 1 discloses a reactor. The reactor includes a shielding member that suppresses leakage magnetic flux. Patent Document 2 discloses a power control device. The power control device includes a reactor and a current sensor. The reactor and the current sensor are arranged close to each other. Patent Document 3 discloses a current sensor. The current sensor includes at least one magnetic shield. The contents of the prior art documents are incorporated by reference as explanations of the technical elements in this specification.

[0004] JP 2019-80021 A JP 2012-105370 A Japanese Patent No. 6919609

[0005] The reactors in the prior art documents are electromagnetic elements, and therefore generate leakage magnetic flux. The leakage magnetic flux may affect the function of nearby electrical components. The leakage magnetic flux may induce noise in electrical circuits through electromagnetic induction. Such noise may have adverse effects, such as reduced functionality of electrical components. For example, there is concern that the performance of sensor elements such as temperature sensors and current sensors may be reduced. Furthermore, elements that utilize electromagnetic effects are more directly susceptible to leakage magnetic flux. For example, there is concern that current sensors that detect current by utilizing electromagnetic effects may be adversely affected, such as by an increase in noise components and errors in the detected current. In the above respects and in other respects not mentioned, further improvements are required in power control devices.

[0006] One disclosed object is to provide a power control device in which adverse effects caused by leakage magnetic flux of a reactor are suppressed.

[0007] Another disclosed object is to provide a power control device that suppresses degradation in performance of a current sensor caused by leakage magnetic flux of a reactor.

[0008] The power control device disclosed herein is a power control device that converts electric power, and includes a conductive member for flowing the current to be converted, a coil electrically connected to the conductive member, and a reactor element having a core for passing magnetic flux induced in the coil, and an electrical component in the power control device that is affected by leakage magnetic flux from the core, wherein the core includes at least a first core having a first magnetic permeability and a second core having a second magnetic permeability greater than the first permeability, and the core and the electrical component are arranged so that a first distance as a path of magnetic flux is formed between the first core and the electrical component, and a second distance as a path of magnetic flux is formed between the second core and the electrical component, and the core and the electrical component are arranged so that a distance relationship is satisfied in which the second distance is shorter than the first distance.

[0009] In the disclosed power control device, the second core has a second magnetic permeability higher than the first magnetic permeability of the first core. Therefore, leakage magnetic flux from the second core is less than leakage magnetic flux from the first core. Therefore, due to the magnetic permeability, the leakage magnetic flux of the second core has little effect on the electrical components. Furthermore, the reactor element and the electrical components are arranged so that the first distance is shorter than the second distance. Therefore, due to the distance relationship, the effect of the leakage magnetic flux of the first core on the electrical components is suppressed.

[0010] The various embodiments disclosed in this specification employ different technical means to achieve their respective objectives. The reference numerals in parentheses in the claims and in this section are intended to exemplify the correspondence with the following embodiments and are not intended to limit the technical scope. The objectives, features, and advantages disclosed in this specification will become more apparent by reference to the following detailed description and the accompanying drawings.

[0011] 1. A block diagram of a power control device according to a first embodiment. A perspective view of the power control device. A cross-sectional view of a sensor unit. A perspective view of a reactor and a sensor unit as viewed from an arrow IV in FIG. 2. A perspective view of a reactor unit and a sensor unit according to a second embodiment. A perspective view of a reactor unit and a sensor unit according to a third embodiment. A perspective view of a reactor unit and a sensor unit according to a fourth embodiment. A perspective view of a reactor unit and a sensor unit according to a fifth embodiment. A perspective view of a reactor unit and a sensor unit according to a sixth embodiment. A perspective view of a reactor unit and a sensor unit according to a seventh embodiment. A perspective view of a reactor unit and a sensor unit according to an eighth embodiment. A perspective view of a reactor unit and a sensor unit according to a ninth embodiment. A perspective view of a reactor unit and a sensor unit according to a tenth embodiment.

[0012] Several embodiments will be described with reference to the drawings. In several embodiments, functionally and / or structurally corresponding and / or associated parts may be designated by the same reference numerals or reference numerals that differ in the hundredth or more digits. For corresponding and / or associated parts, reference may be made to the descriptions of other embodiments.

[0013] First Embodiment FIG. 1 is a block diagram showing a vehicle power system 1. In this embodiment, the vehicle is a vehicle that travels on land. The vehicle is an electric vehicle powered by a rotating electric machine that provides running power using electricity. The vehicle may additionally include an internal combustion engine that provides running power using fuel. The vehicle is also called a hybrid vehicle, a plug-in hybrid vehicle, a battery-electric vehicle, etc. The vehicle may be a ship that travels on water, an aircraft that travels through the air, or a spacecraft in outer space.

[0014] The power system 1 includes a power control device 2. The power control device 2 is electrically connected to and disposed between a battery 3 and a rotating electric machine 4. The power control device 2 provides bidirectional or unidirectional conversion between DC and AC. Furthermore, the power control device 2 provides DC power regulation and / or AC power regulation. The power control device 2 provides DC-AC conversion, converting DC power supplied from the battery 3 into AC power and supplying it to the rotating electric machine 4. Furthermore, the power control device 2 provides ACDC conversion, converting AC power supplied from the rotating electric machine 4 into DC power and charging the battery 3.

[0015] The power system 1 includes a battery 3. The battery 3 is a DC power source. In this embodiment, the battery 3 is a secondary battery that can be charged and discharged. The DC power source can be any of a variety of batteries, such as a lead-acid battery, a lithium-ion battery, or a nickel-cadmium battery. Furthermore, the DC power source may be provided by a fuel cell.

[0016] The power system 1 includes a rotating electric machine 4. An example of the rotating electric machine 4 is an electric motor. Another example of the rotating electric machine 4 is a generator motor (MG). An example of the rotating electric machine 4 is an AC rotating electric machine. An example of the rotating electric machine 4 is a polyphase AC rotating electric machine. In this embodiment, the rotating electric machine 4 is a three-phase AC rotating electric machine.

[0017] The power control device 2 has a converter (CONV) 5 and an inverter (INV) 6. The converter 5 and the inverter 6 are connected in series and disposed between the battery 3 and the rotating electric machine 4. The power control device 2 converts electric power. The power control device 2 is also called a power conversion device. The power control device 2 includes conductive members 2a for passing the converted current. The conductive members 2a are members for passing the large converted current. The conductive members 2a are provided by bus bars. The conductive members 2a may be laid out vertically and horizontally within the power control device 2 to enable efficient current flow. The conductive members 2a are disposed between the converter 5 and the inverter 6, between the inverter 6 and the rotating electric machine 4, and the like.

[0018] The converter 5 has a primary end and a secondary end. In this embodiment, the battery 3 is connected to the primary end, and the inverter 6 is connected to the secondary end. The converter 5 provides a step-up function that increases the voltage between the primary end and the secondary end. The converter 5 provides a step-down function that decreases the voltage between the primary end and the secondary end. The converter 5 provides the step-up function and / or the step-down function. The converter 5 is provided by a chopper circuit. The chopper circuit includes a reactor unit (L) 7 and a switching element. The reactor unit 7 is an electromagnetic element that converts electric energy and magnetic energy into each other. The converter 5 may be provided by a circuit including a transformer. In this case, the transformer is the electromagnetic element.

[0019] The inverter 6 has a DC end and an AC end. In this embodiment, the converter 5 is connected to the DC end, and the rotating electric machine 4 is connected to the AC end. The inverter 6 provides a DC / AC conversion function of converting DC power input to the DC end into AC power and outputting it to the AC end. The inverter 6 provides an ACDC conversion function of converting AC power input to the AC end into DC power and outputting it to the DC end. The inverter 6 provides the DC / AC conversion function and / or the ACDC conversion function. The AC end has multiple terminals corresponding to polyphase AC. In the illustrated example, the AC end corresponds to three-phase AC. The inverter 6 is provided by a bridge circuit including multiple switching arms. The multiple switching arms are provided by multiple switching elements.

[0020] The switching elements of the converter 5 and the inverter 6 may be the same type or different types. The switching elements may be implemented by a switch module including one or more switching elements. The switching elements may be implemented by a variety of switching elements, such as IGBTs, power MOSs, and SiC elements.

[0021] The power control device 2 has a capacitor unit (C) 8. The capacitor unit 8 includes a capacitor element connected between a positive electrode member and a negative electrode member between the converter 5 and the inverter 6. The capacitor unit 8 smoothes the DC power between the converter 5 and the inverter 6.

[0022] The power control device 2 includes a sensor unit 9. The sensor unit 9 measures currents in current paths in the power control device 2 and outputs an electrical signal indicating the amount of current. The sensor unit 9 includes at least one current measurement unit 30 for measuring currents in at least one current path. The current measurement unit 30 is an electrical component in the power control device 2. The current measurement unit 30 is an electrical component that is affected by leakage magnetic flux from a core of a reactor element (described later). The current measurement unit 30 is an electromagnetic component that detects magnetic flux resulting from current flowing through a conductive member. In this embodiment, the sensor unit 9 includes multiple current measurement units 30. In this case, the sensor unit 9 is also referred to as a current sensor unit. The multiple current measurement units 30 include at least multiple current measurement units 30 that measure multi-phase currents flowing between the inverter 6 and the rotating electric machine 4. The multiple current measurement units 30 include at least one current measurement unit 30 that measures DC currents flowing between the converter 5 and the inverter 6. In the illustrated example, the sensor unit 9 includes at least four current measurement units 30. The sensor unit 9 outputs a plurality of detection signals, which are input to a control circuit 10, which will be described later.

[0023] The sensor unit 9 includes a housing formed primarily from an electrically insulating resin material. The housing holds a conductive member through which the current to be detected flows. The housing may include a plurality of conductive members. The housing holds a plurality of components that constitute a current measurement unit 30. The housing may include a plurality of current measurement units 30. Each of the plurality of current measurement units 30 is disposed and functions in correspondence with each of the plurality of conductive members.

[0024] The sensor unit 9 may have a plurality of partial units that are separated from one another. Each of the plurality of partial units may include one of the plurality of conductive members, or two or more of the plurality of conductive members. In this case, each of the plurality of partial units includes a current measuring unit 30 corresponding to the conductive member associated therewith. Even in such a case, the power control device 2 has a sensor unit 9 that includes a plurality of partial units.

[0025] The current measurement unit 30 utilizes electromagnetic effects. The current measurement unit 30 has a measurement element. The current measurement unit 30 positions the measurement element so as to face the conductive member through which the current to be measured flows, without directly contacting the conductive member. The current measurement unit 30 outputs an electrical signal indicating the current measured by the measurement element.

[0026] The power control device 2 includes a control circuit 10. The control circuit 10 receives an electrical signal from the sensor unit 9. The control circuit 10 controls at least one switching element in the converter 5 and the inverter 6. The control circuit 10 controls the on-timing and / or off-timing of the switching element. The control circuit 10 controls the voltage supplied to the rotating electric machine 4 and / or the current supplied to the rotating electric machine 4 by controlling the switching element. The control circuit 10 controls the voltage supplied to the battery 3 and / or the current supplied to the battery 3 by controlling the switching element.

[0027] The control circuit in this specification may also be called an Electronic Control Unit (ECU) or a control system.

[0028] The control circuit is provided by a control system including at least one computer. The control system is provided by (a) an algorithm in the form of multiple logics called if-then-else forms, or (b) an algorithm in the form of a trained model tuned by machine learning, for example, a neural network. The control system may include multiple computers linked by a data communication device. The computer includes at least one processor that is hardware (a hardware processor). The hardware processor can be provided by the following (i), (ii), or (iii):

[0029] (i) A hardware processor may be at least one processor core that executes a program stored in at least one memory. In this case, a computer is provided with at least one memory and at least one processor core. The processor core is called a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), a RISC-CPU, or the like. A memory is also called a storage medium. A memory is a non-transitory, tangible storage medium that non-temporarily stores "programs and / or data" that can be read by a processor. The storage medium is provided by a semiconductor memory, a magnetic disk, an optical disk, or the like. A program may be distributed independently or as a storage medium on which the program is stored.

[0030] (ii) A hardware processor may be a hardware logic circuit. In this case, the computer is provided by a digital circuit including a large number of programmed logic units (gate circuits). The digital circuit is also called a logic circuit array, for example, ASIC: Application-Specific Integrated Circuit, FPGA: Field Programmable Gate Array, SoC: System on a Chip, PGA: Programmable Gate Array, CPLD: Complex Programmable Logic Device, etc. The digital circuit may include a memory that stores programs and / or data. The computer may be provided by an analog circuit. The computer may be provided by a combination of digital and analog circuits.

[0031] (iii) The hardware processor may be a combination of (i) and (ii) above, where (i) and (ii) are located on different chips or on a common chip. In these cases, part (ii) is also called an accelerator.

[0032] The control system and control method performed by the control system described in this disclosure may be implemented by a special-purpose computer configured by configuring a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the control unit and method described in this disclosure may be implemented by a special-purpose computer configured by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control unit and method described in this disclosure may be implemented by one or more special-purpose computers configured by combining a processor and memory programmed to perform one or more functions with a processor configured with one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by a computer on a computer-readable non-transitory tangible storage medium.

[0033] 2 shows an example of the installation posture of the power control device 2 and the arrangement of components within the power control device 2. As shown in the figure, the components of the power control device 2 are housed in a housing 20. The housing 20 is made of resin or metal. From the viewpoint of suppressing electromagnetic noise emitted from the power control device 2 and / or from the viewpoint of suppressing electromagnetic noise arriving from outside the power control device 2, it may be desirable for the housing 20 to be made of a material that has an electromagnetic shielding effect.

[0034] The power control device 2, i.e., the housing 20, has a three-dimensional shape with an internal volume capable of accommodating multiple components. The housing 20 has a three-dimensional shape with a width in the width direction (x direction), a height in the height direction (y direction), and a depth in the depth direction (z direction). Note that FIG. 2 is merely an example of an installation orientation of the power control device 2. The power control device 2 can be installed in a variety of orientations, such as vertical, horizontal, and diagonal. Also, FIG. 2 is merely an example of an arrangement of multiple components within the housing 20. The multiple components may be arranged so that two components are stacked vertically and / or so that two components are aligned horizontally. The width, height, and depth shown in the figure are convenient names that represent the installation state shown in the figure.

[0035] The sensor unit 9 has a plurality of current measurement units 30. The plurality of current measurement units 30 are arranged in a row along the longitudinal direction of the sensor unit 9, that is, along the depth direction (z direction) in the drawing.

[0036] The reactor unit 7 has a plurality of reactor elements 40. The reactor elements 40 are electromagnetic energy storage elements. The plurality of reactor elements 40 are arranged in a row along the longitudinal direction of the reactor unit 7, that is, the depth direction (z direction) in the drawing. The plurality of reactor elements 40 may be arranged in one row or in multiple rows.

[0037] Components of the power control device 2 include a converter 5 and an inverter 6. Further components of the power control device 2 include a reactor unit 7, a capacitor unit 8, a sensor unit 9, and a control circuit 10. The reactor unit 7 and the capacitor unit 8 are also circuit elements of the converter 5. The converter 5 and the inverter 6 include a plurality of switching elements, which are their main circuit elements. The power control device 2 includes a heat dissipation module 11 for dissipating heat from these switching elements.

[0038] The multiple switching elements are incorporated into the heat dissipation module 11. For example, the multiple switching elements may be provided by multiple switch modules 12. One switch module 12 may be provided by a semiconductor package having a rectangular, flat plate-like appearance. The heat dissipation module 11 is arranged in contact with one or both sides of the multiple switch modules 12 to enable heat dissipation from one or both sides of the multiple switch modules 12. The heat dissipation module 11 defines a medium passage for flowing a heat medium. The heat dissipation module 11 provides heat exchange between the multiple switch modules 12 and the heat medium. In the power system 1, the heat medium includes a heat medium circulation path installed outside the power control device 2. The heat medium circulation path includes a heat exchanger that cools the heat medium. The heat medium receives heat from the heat dissipation module 11 by flowing through the heat dissipation module 11. Furthermore, the heat medium flows through the heat medium circulation path and passes through the heat exchanger to release heat. For example, the heat of the heat medium is dissipated to the outside air. The heat of the heat medium may be dissipated via a refrigeration cycle.

[0039] As shown in FIG. 2 , the components of the power control device 2 are arranged adjacent to one another within a housing 20. The shape of the housing 20 and the layout of the components within the housing 20 are determined in accordance with various requirements. One of the requirements is to enable mounting of the power system 1. Another of the requirements is to suppress Joule heat within the power control device 2. Another of the requirements is to suppress inductance components and / or capacitance components that affect the high-frequency characteristics of the power control device 2. Therefore, it should be understood that the layout of the components shown in FIG. 2 is merely exemplary, and that various modifications to the layout of the components are possible.

[0040] The reactor unit 7 and the sensor unit 9 are arranged adjacent to each other in any direction. In the illustrated example, the reactor unit 7 and the sensor unit 9 are arranged adjacent to each other in the width direction (x direction). The reactor unit 7 and the sensor unit 9 are also adjacent to each other in the diagonal direction between the width direction (x direction) and the depth direction (z direction). However, here, the direction that defines the shortest distance, i.e., the width direction (x direction), is defined as the adjacent direction.

[0041] The reactor unit 7 and the sensor unit 9 are arranged so that the reactor element 40 and the current measurement unit 30 are adjacent to each other in any direction. As a result, the reactor element 40 and the current measurement unit 30 are arranged so that they are adjacent to each other in any direction. In the illustrated example, the reactor element 40 and the current measurement unit 30 are arranged adjacent to each other in the width direction (x direction). Note that the reactor element 40 and the current measurement unit 30 are also adjacent to each other in the diagonal direction between the width direction (x direction) and the depth direction (z direction). However, here, the direction that defines the shortest distance, i.e., the width direction (x direction), is defined as the adjacent direction.

[0042] The reactor unit 7 and the sensor unit 9 are adjacent to each other so that the outer wall surface of the reactor unit 7 and the outer wall surface of the sensor unit 9 are positioned parallel to each other. This arrangement allows the reactor element 40 and the current measurement unit 30 to be positioned close to each other. Furthermore, this arrangement contributes to the miniaturization of the power control device 2. The reactor unit 7 and the sensor unit 9 may also be positioned so that the outer wall surface of the reactor unit 7 and the outer wall surface of the sensor unit 9 face each other non-parallel.

[0043] Between the reactor element 40 and the current measuring section 30, a resin member that provides a housing for the reactor unit 7 and / or a resin member that provides a housing for the sensor unit 9 is arranged.

[0044] In FIG. 2 , the reactor unit 7 and the switch module 12 are adjacent to each other in any direction. The reactor unit 7 and the switch module 12 are adjacent to each other in the height direction (y direction). The switch module 12 may include one or more temperature sensors. The one or more temperature sensors measure the temperature of one or more locations within the switch module 12 and output a temperature signal indicating the temperature. The temperature signal is input to the control circuit 10. Based on the temperature signal, the control circuit 10 performs temperature control to protect the switch module 12 and the switching elements. The temperature control is performed on the converter 5 and / or the inverter 6.

[0045] The temperature sensor may be adversely affected by leakage magnetic flux from the reactor element 40. For example, the leakage magnetic flux may electromagnetically affect the detection characteristics of the temperature sensor. The leakage magnetic flux may also heat the temperature sensor by electromagnetic induction, causing a change in the measurement value of the temperature sensor. In these cases, the temperature sensor is affected by the leakage magnetic flux from the reactor element 40.

[0046] 3 shows a cross section of the sensor unit 9. The sensor unit 9 includes a housing 31. The housing 31 holds multiple components that constitute the current measurement unit 30. The housing 31 holds a conductive member 32. The housing 31 may include multiple conductive members 32. The housing 31 may include multiple current measurement units 30. One current measurement unit 30 is associated with one conductive member 32. The current measurement unit 30 is positioned at a predetermined position relative to the conductive member 32 so as to generate a measurement signal indicating a predetermined current value when a predetermined current flows through the conductive member 32.

[0047] The current measurement unit 30 includes a sensor element 33. The sensor element 33 measures the current flowing through the conductive member 32 by utilizing an electromagnetic effect. For example, the sensor element 33 generates a measurement signal in response to a magnetic flux Sf generated around the conductive member 32 in response to the current flowing through the conductive member 32. The sensor element 33 provides a magnetoelectric conversion unit that converts the magnetic flux into an electric signal. The magnetoelectric conversion unit includes a magnetoresistive element. The sensor element 33 is implemented as a semiconductor chip. The current measurement unit 30 includes a circuit board 34 on which the sensor element 33 is mounted. The circuit board 34 provides a positioning member that positions the sensor element 33 with high precision. The circuit board 34 has a circuit for the sensor element 33. The circuit board 34 includes a drive circuit for operating the sensor element 33. Furthermore, the circuit board 34 includes a processing circuit that processes the measurement signal output by the sensor element 33.

[0048] The sensor element 33 includes a magnetic body 33a that is affected by leakage magnetic flux from the reactor element. The circuit board 34 includes a circuit 34a that is affected by leakage magnetic flux from the reactor element. The circuit 34a may be understood as a circuit pattern formed on the circuit board 34. Furthermore, in this embodiment, the current measurement unit 30 includes both the magnetic body 33a and the circuit 34a. Alternatively, the current measurement unit 30 may be configured to include only one of the magnetic body 33a or the circuit 34a.

[0049] The current measurement unit 30 includes a magnetic shielding member 35. The current measurement unit 30 may not include the shielding member 35. The shielding member 35 is an optional component that can be selectively adopted. Compared to the shielding member 35, the housing 31 and the circuit board 34 have significantly lower magnetic shielding function. The shielding member 35 is made of a ferromagnetic material such as an electromagnetic steel plate. The magnetic flux Sf can be called the internal magnetic flux that is generated in the conductive member 32 and measured by the sensor element 33. In this case, the magnetic flux that arrives at the current measurement unit 30 from outside the current measurement unit 30 can be called the external magnetic flux Nf.

[0050] The shield member 35 functions as a magnetic guide member that guides the magnetic flux Sf. The shield member 35 stabilizes the magnetic flux Sf that intersects with the sensor element 33. For example, the sensor element 33 may have a measurement axis that measures magnetic flux in a specific direction. The shield member 35 stabilizes the magnetic flux in the measurement axis among the magnetic flux that attempts to intersect with the sensor element 33. From another perspective, the shield member 35 captures the external magnetic flux Nf. As a result, the shield member 35 suppresses the effect of the external magnetic flux Nf on the sensor element 33.

[0051] The shield member 35 may include a first shield member 36 and a second shield member 37. The conductive member 32 and the sensor element 33 form a component pair that generates and measures the internal magnetic flux Sf. The component pair is arranged to face each other in a predetermined facing direction. The first shield member 36 and the second shield member 37 are arranged to sandwich the component pair from the outside in this facing direction. The shield member 35 may be formed from a single member. For example, the shield member 35 may include only either the first shield member 36 or the second shield member 37. For example, the shield member 35 may be provided as a single continuous member including members corresponding to the first shield member 36 and the second shield member 37.

[0052] The current measuring unit 30, the sensor element 33, and the shielding member 35 are described in detail in Japanese Patent No. 6919609, which is incorporated herein by reference.

[0053] 4 shows a cross section of the reactor unit 7 and the sensor unit 9 in the xy plane. The reactor unit 7 and the sensor unit 9 are arranged adjacent to each other in the width direction (x direction). The distance between the reactor unit 7 and the sensor unit 9 is short enough that the leakage magnetic flux of the reactor element 40 reaches the current measurement unit 30. The distance between the reactor unit 7 and the sensor unit 9 is short enough that the leakage magnetic flux of the reactor element 40 interlinks with the sensor element 33.

[0054] The reactor element 40 and the current measurement unit 30 are arranged adjacent to each other with no member between them that can function as an electromagnetic shield other than the shield member 35. In this arrangement, leakage magnetic flux from the reactor element 40 may affect the current measurement unit 30. For example, the leakage magnetic flux may change the magnetic flux distribution in the current measurement unit 30. Furthermore, the leakage magnetic flux may be directly detected by the current measurement unit 30. In these cases, the current measurement unit 30, which utilizes electromagnetic effects, is affected by the leakage magnetic flux from the reactor element 40.

[0055] Here, the current measurement unit 30 may include a shield member 35. However, even if leakage magnetic flux only reaches the shield member 35, the magnetic flux linking to the sensor element 33 may change. Therefore, the following embodiment also takes into consideration the influence of leakage magnetic flux from the reactor element 40 reaching the current measurement unit 30 including the shield member 35. Note that the current measurement unit 30 shown in FIG. 4 may be used as the position of the sensor element 33 to evaluate the distance, etc., described below.

[0056] The reactor element 40 includes a core 45 and a coil 46. The coil 46 is electrically connected to the conductive member 2a. The coil 46 includes a conductive member wound around a coil axis CX. In the illustrated example, the coil axis CX is positioned along the x direction. The coil axis CX is arranged to point toward the current measurement unit 30. The coil axis CX is arranged to intersect with the current measurement unit 30. The coil axis CX is arranged to intersect with the sensor element 33. The illustrated coil 46 includes a single coil portion. Alternatively, the coil 46 may include multiple coil portions. For example, multiple coil portions, such as two or three, may be provided in multiple magnetic path portions formed by the core 45 described below.

[0057] The core 45 passes magnetic flux induced in the coil 46. The core 45 is provided by two E-shaped cores. The core 45 is also called an EE core. The two E-shaped cores are arranged to form an E shape on the x-y plane. The two E-shaped cores are arranged and connected so that the three ends of one E-shaped core face the three ends of the other E-shaped core. The core 45 forms a magnetic path MP through which magnetic flux induced in the coil 46 passes when current flows through the coil 46. The core 45 can be provided in various layouts, including an EE core. For example, various cores such as an EI core, UI core, UU core, OI core, and UIU core can be used instead of the EE core. The core 45 can be provided using various materials, such as a laminate of electromagnetic steel sheets or a powder compact.

[0058] In Fig. 4, the magnetic flux path MP is indicated by a two-dot chain line. The core 45 forms a closed magnetic flux path MP. The core 45 is a gapless core. The core 45 includes a plurality of cores. The core includes a first core 41 and a second core 42. The junction boundary between the first core 41 and the second core 42 is positioned inside the coil 46. However, the core 45 generates leakage magnetic flux.

[0059] The core 45 forms a magnetic flux path MP. The magnetic flux path MP extends along the xy plane. The magnetic flux path MP may include a plurality of magnetic flux path portions. Furthermore, the magnetic flux path MP includes a common magnetic flux path and a plurality of individual magnetic flux paths. The common magnetic flux path is a magnetic flux path common to a plurality of magnetic flux path portions. The plurality of individual magnetic flux paths are magnetic flux paths that characterize each of the plurality of magnetic flux path portions. In the illustrated example, the coil 46 is provided in the common magnetic flux path. Note that the coil 46 may have a plurality of coil portions. In this case, the plurality of coil portions may be provided in a distributed manner in the common magnetic flux path and / or the plurality of individual magnetic flux paths.

[0060] The first core 41 and the second core 42 have different magnetic permeabilities M. The magnetic permeability M1 of the first core 41 is lower than the magnetic permeability M2 of the second core 42 (M1<M2). The magnetic permeability M1 of the first core 41 and the magnetic permeability M2 of the second core 42 are set to adjust the electromagnetic characteristics of the reactor element 40. The magnetic permeability M1 is also referred to as the first magnetic permeability. The magnetic permeability M2 is also referred to as the second magnetic permeability. For example, the difference between the magnetic permeability M1 of the first core 41 and the magnetic permeability M2 of the second core 42 adjusts the inductance of the reactor element 40. For example, the difference between the magnetic permeability M1 of the first core 41 and the magnetic permeability M2 of the second core 42 adjusts the saturation magnetic flux density. Note that the cores 45 may have an air gap at their boundary.

[0061] Due to the magnetic permeabilities M1 and M2, the magnetic flux density of the leakage magnetic flux around the first core 41 is higher than the magnetic flux density of the leakage magnetic flux around the second core 42. As a result, there is concern that the leakage magnetic flux from the first core 41 may affect the function of electrical components arranged adjacent to the first core 41. The effect can be evaluated based on the frequency of the effect, the magnitude of the effect, the duration of the effect, etc. The effect of the leakage magnetic flux from the first core 41 on electrical components arranged adjacent to the first core 41 is also referred to as the first effect.

[0062] On the other hand, due to the magnetic permeabilities M1 and M2, the magnetic flux density of the leakage magnetic flux around the second core 42 is lower than the magnetic flux density of the leakage magnetic flux around the first core 41. As a result, the influence of the leakage magnetic flux from the second core 42 on the function of electrical components arranged adjacent to the second core 42 is relatively low. The influence of the leakage magnetic flux from the second core 42 on electrical components arranged adjacent to the second core 42 is also referred to as the second influence. Here, the term "relative" is based on a comparison between the first influence and the second influence.

[0063] The first core 41 has the smallest magnetic permeability M1 of the cores of the reactor element 40. The second core 42 has a non-smallest magnetic permeability M2 of the cores of the reactor element 40. The first core 41 can also be said to be another core having a different magnetic permeability from the second core 42. The first core 41 can also be said to be another core having a lower magnetic permeability than the second core 42.

[0064] In the following description, the current measurement unit 30, which is an example of an electrical component, will be used as an example. Those skilled in the art should understand that the current measurement unit 30 can be interpreted as an electrical component. Furthermore, those skilled in the art should understand that the current measurement function can be interpreted as the function of an electrical component. An electrical component is a component that is affected by leakage magnetic flux. An electrical component includes, for example, an inductance element, a capacitance element, or a resistance element. Furthermore, an electrical component can have various functions, such as a temperature measurement function or a water submersion detection function. Furthermore, an electrical component can be implemented in various forms, such as a semiconductor element, a surface-mounted element, or a through-hole-mounted element.

[0065] The leakage magnetic flux from the first core 41 affects the current measurement function of the current measurement unit 30 arranged adjacent to the first core 41. The effect is manifested in noise in the output signal from the current measurement unit 30, deviation of the output signal, etc. The leakage magnetic flux from the second core 42 affects the current measurement function of the current measurement unit 30 arranged adjacent to the second core 42. The effect on the current measurement function of the current measurement unit 30 arranged adjacent to the second core 42 is relatively smaller than the effect on the current measurement function of the current measurement unit 30 arranged adjacent to the first core 41. The relative smallness of the effect can be grasped by the smallness of noise in the output signal from the current measurement unit 30, the smallness of deviation of the output signal, etc.

[0066] FIG. 4 illustrates the boundary CB between the first core 41 and the second core 42. In the illustrated example, the boundary CB is one of the y-z planes. The boundary CB is also the boundary surface between the region where the first core 41 is located and the region where the second core 42 is located. The boundary surface is defined by multiple connecting surfaces between the first core 41 and the second core 42 and imaginary surfaces that extend radially outward from these connecting surfaces. The current measurement unit 30 is disposed in the region where the second core 42 is located. In other words, the current measurement unit 30 is disposed closer to the region where the second core 42 is located than the boundary CB. The core 45 defines the boundary CB that separates the region where the first core 41 is located from the region where the second core 42 is located. The current measurement unit 30 is disposed closer to the region where the second core 42 is located than the boundary CB.

[0067] The uneven placement of the current measurement unit 30 with respect to the boundary CB is called an uneven distribution relationship. From one perspective, satisfying this uneven distribution relationship suppresses the influence of the other core (first core 41) on the electrical component (current measurement unit 30).

[0068] In FIG. 4 , the reactor element 40 and the current measurement unit 30 are adjacent to each other in the x-y plane. The reactor element 40 and the current measurement unit 30 are disposed adjacent to each other in the x direction. In other words, the shortest distance between the reactor element 40 and the current measurement unit 30 is defined in the x direction. The x direction is also referred to as the direction in which the reactor element 40 and the current measurement unit 30 are adjacent to each other. The shortest distance between the reactor element 40 and the current measurement unit 30 may be given by the distance between the surface of the core of the reactor element 40 and the surface of the sensor element 33 of the current measurement unit 30. The shortest distance between the reactor element 40 and the current measurement unit 30 is also the shortest distance of the magnetic flux path that the magnetic flux emitted from the reactor element 40 takes to reach the current measurement unit 30.

[0069] Even when spatial arrangement is taken into consideration, the specific reactor element 40 and the specific current measurement unit 30 are adjacent to each other. They are arranged at the shortest spatial distance. For example, the spatial distance between another reactor element 40 included in the reactor unit 7 and the specific current measurement unit 30 is longer than the shortest distance described above. For example, the spatial distance between another current measurement unit 30 included in the sensor unit 9 and the specific reactor element 40 is longer than the shortest distance described above.

[0070] The shortest distance between the first core 41 and the current measurement unit 30 is distance D1. The shortest distance between the second core 42 and the current measurement unit 30 is distance D2. Distances D1 and D2 are defined as distances in the x direction, i.e., distances in the adjacent direction. Distances D1 and D2 are also the distance of the magnetic flux path that the magnetic flux emitted from the reactor element 40 takes to reach the current measurement unit 30 via the shortest magnetic flux path. Distance D2 is shorter than distance D1. As a result, the influence of the reactor element 40 on the current measurement unit 30 (an electrical component) is relatively small.

[0071] In the adjacent relationship, the distance D2 between the second core 42, which does not have the smallest magnetic permeability, and the electrical component is shorter than the distance D1 between the other core (first core 41) and the electrical component.

[0072] In this embodiment, the arrangement characterized by the distance D1 between the first core 41 and the current measurement unit 30 and the distance D2 between the second core 42 and the current measurement unit 30 is also referred to as the distance relationship in the following description. From one perspective, satisfying this distance relationship suppresses the influence of the other core (first core 41) on the electrical component (current measurement unit 30).

[0073] The second core 42 is disposed between the current measurement unit 30 and the first core 41. Moreover, the second core 42 is disposed so as to completely obscure the first core 41 from the current measurement unit 30. This relationship is satisfied both in the illustrated xy plane and in the unillustrated xz plane. For example, assume that the first core 41 and the second core 42 are seen through from the current measurement unit 30. Under this assumption, the first core 41 is completely obscured by the second core 42.

[0074] In FIG. 4 , a virtual line of sight VL is indicated by a dashed line. The line of sight VL can reach the second core 42 but cannot reach the first core 41. When considering the path of magnetic flux, leakage magnetic flux from the first core 41 may bypass the second core 42 and reach the current measurement unit 30. In this case, the leakage magnetic flux requires a relatively long detour. Therefore, the influence of the detour is smaller than the influence of passing through the linear distances D1 and D2. Therefore, the second core 42, which has a relatively high magnetic permeability M2, also serves as a cover member that conceals the electrical component (current measurement unit 30) from the first core 41, which has a relatively low magnetic permeability M1. Therefore, in this embodiment, the second core 42 is disposed between the first core 41 and the current measurement unit 30. This prevents the first core 41 from reaching the current measurement unit 30 in a linear manner.

[0075] In the following description, the arrangement of the second core 42 between the first core 41 and the current measurement unit 30 in this embodiment is also referred to as a “cover relationship.” From one perspective, satisfying the cover relationship reduces the influence of the other core (the first core 41) on the electrical component (the current measurement unit 30).

[0076] According to this embodiment, leakage magnetic flux from the core (second core 42) having a magnetic permeability M2 that is not the minimum among the cores of the reactor element 40 is relatively small. Therefore, the influence of the core (second core 42) having a magnetic permeability M2 that is not the minimum among the cores of the reactor element 40 on the electrical component (current measurement unit 30) is small. On the other hand, by satisfying at least one of the maldistribution relationship, distance relationship, and cover relationship, the influence of leakage magnetic flux from the core (first core 41) having a magnetic permeability M1 lower than that of the second core 42 on the electrical component (current measurement unit 30) is suppressed. In this embodiment, all of the maldistribution relationship, distance relationship, and cover relationship are satisfied. As a result, the influence of leakage magnetic flux from the reactor element 40 on the electrical component (current measurement unit 30) is suppressed.

[0077] According to the embodiment described above, in a power control device 2 in which components must be placed adjacent to each other, it is possible to suppress the influence of leakage magnetic flux from the reactor on electrical components other than the reactor. Moreover, the reactor element 40 can have desirable electromagnetic characteristics by including multiple cores with different magnetic permeabilities. Therefore, it is possible to suppress the influence of leakage magnetic flux on other electrical components while improving the electromagnetic characteristics of the reactor. Furthermore, it is possible to improve the characteristics and functions of the power control device.

[0078] Second Embodiment This embodiment is a modification of the preceding embodiment as a basic form. In the following subsequent embodiments, the same components as those in the preceding embodiment and components providing equivalent functions are denoted by the same reference numerals. For an explanation of these components, please refer to the explanation of the preceding embodiment.

[0079] 5 shows a second embodiment. In the first embodiment, the core 45 is arranged so that the magnetic flux path MP extends along the x-y plane. Instead, in the second embodiment, the core 245 is arranged so that the magnetic flux path MP extends along the x-z plane. In this embodiment, the coil axis CX is also positioned so as to point toward the current measurement unit 30. In this embodiment, the maldistribution relationship, the distance relationship, and the cover relationship are all satisfied. As a result, the same effects as those of the preceding embodiment are obtained.

[0080] Third Embodiment This embodiment is a modification of the preceding embodiment as a basic form.

[0081] 6 shows a third embodiment. In the first embodiment, the core 45 is arranged so that the core axis CX is oriented toward the current measurement unit 30. Instead, in the third embodiment, the core 345 is arranged so that the core axis CX is not oriented toward the current measurement unit 30. In this embodiment, the core 345 is arranged so that the magnetic flux path MP extends along the xy plane. Note that the core 345 may also be arranged so that the magnetic flux path MP extends along the xz plane.

[0082] In this embodiment, the current measurement unit 30 is adjacent to both the first core 41 and the second core 42. However, with respect to the distances D1 and D2, the core 345 is positioned closer to the second core 42 than to the first core 41.

[0083] The shortest distance between the first core 41 and the current measurement unit 30 is distance D1. Distance D1 is defined as a diagonal distance that intersects both the x direction and the y direction in the xy plane.

[0084] The core 345 is arranged so that the second core 42 and the current measurement unit 30 are adjacent to each other in the x direction. In other words, the second core 42 and the current measurement unit 30 are arranged so as to define the shortest distance D2. The distance between the second core 42 and the current measurement unit 30 is the distance D2. The distance D2 is defined as the distance in the x direction, i.e., the shortest distance in the adjacent direction.

[0085] The distance D2 is shorter than the distance D1. As a result, the influence of the reactor element 40 on the current measuring unit 30 (an electrical component) is relatively small.

[0086] In this embodiment, the above-described uneven distribution relationship and distance relationship are also satisfied. On the other hand, in this embodiment, the above-described cover relationship is not satisfied. According to this embodiment, an effect based on the uneven distribution relationship and distance relationship can be obtained.

[0087] Fourth Embodiment This embodiment is a modification of the preceding embodiment as a basic form.

[0088] FIG. 7 shows a fourth embodiment. In the preceding embodiments, the core 45 is provided by an EE core. Instead, the core 445 is provided by an EI core. The first core 41 is E-type. The second core 42 is I-type. In this embodiment, the E-type and I-type may be reversed. In this embodiment, all of the above-mentioned uneven distribution relationship, distance relationship, and cover relationship are satisfied. As a result, the same effects as those of the first embodiment are obtained.

[0089] Fifth Embodiment This embodiment is a modification of the preceding embodiment as a basic form.

[0090] FIG. 8 shows a fifth embodiment. The core 445 is arranged so that the core axis CX is oriented toward the current measurement unit 30. Instead, in the fifth embodiment, the core 545 is arranged so that the core axis CX is not oriented toward the current measurement unit 30. In other words, the core axis CX is arranged to avoid the current measurement unit 30. The core 545 is arranged so that a distance D1 is formed between the first core 41 and the current measurement unit 30, and a distance D2 is formed between the second core 42 and the current measurement unit 30. In this embodiment, the adjacent direction is a slightly downward-sloping diagonal direction in the figure. Therefore, the x-axis display in FIG. 8 is slightly rotated clockwise around the z-axis. In this embodiment, the above-described uneven distribution relationship and distance relationship are satisfied. Therefore, the effects based on the uneven distribution relationship and distance relationship are obtained.

[0091] Sixth Embodiment This embodiment is a modification of the preceding embodiment as a basic form.

[0092] 9 shows a sixth embodiment. The core 645 is provided by a UI core. The first core 41 is U-shaped. The second core 42 is I-shaped. The U-shaped and I-shaped cores may be reversed.

[0093] This embodiment illustrates a coil 46 having multiple coil portions. The coil 46 has a first coil portion 647 and a second coil portion 648. The first coil portion 647 is characterized by a coil axis CX1. The second coil portion 648 is characterized by a coil axis CX2. The coil axes CX1 and CX2 are arranged parallel to each other. In this embodiment, the adjacent direction is the up-and-down direction in the figure. Therefore, the axis indication in FIG. 9 is rotated 90 degrees counterclockwise around the z-direction. In this embodiment, the above-described uneven distribution relationship and distance relationship are also satisfied. As a result, the effects based on the uneven distribution relationship and distance relationship are obtained.

[0094] Seventh Embodiment This embodiment is a modification of the preceding embodiment as a basic form.

[0095] 10 shows a seventh embodiment. The core 745 is provided by a UU core. The first core 41 is U-shaped. The second core 42 is U-shaped. The first core 41 and the second core 42 are butted together in the x-direction. The first core 41 and the second core 42 may also be butted together in the y-direction.

[0096] The first core 41 and the second core 42 are connected at two connecting portions. The boundary CB includes the two connecting portions. In this embodiment, the two connecting portions are located within the coil 46, i.e., within the first coil portion 647 and the second coil portion 648. The above-described maldistribution relationship and distance relationship are also satisfied. As a result, the effects based on the maldistribution relationship and distance relationship are obtained.

[0097] Eighth Embodiment This embodiment is a modification of the preceding embodiment as a basic form.

[0098] 11 shows an eighth embodiment. The core 845 is provided by a combined core including two I-cores in addition to a UU core. The core 845 includes a first core 41, a second core 42, and a third core 43. The first core 41 is U-shaped. The second core 42 is also U-shaped. The third core 43 has two sections disposed between the first core 41 and the second core 42. Each section of the third core 43 is provided by an I-core.

[0099] The magnetic permeability M1 of the first core 41 is smaller than the magnetic permeability M2 of the second core 42 (M1<M2). The magnetic permeability M1 of the first core 41 is smaller than the magnetic permeability M3 of the third core 43 (M1<M3). The magnetic permeability M3 is also called the third magnetic permeability. The magnetic permeability M2 of the second core 42 is smaller than the magnetic permeability M3 of the third core 43 (M2<M3). Therefore, the magnetic permeability M1 of the first core 41 is the smallest magnetic permeability among the partial cores that make up core 845. The magnetic permeability M2 of the second core 42 is the middle magnetic permeability among the partial cores that make up core 845. The magnetic permeability M3 of the third core 43 is the largest magnetic permeability among the partial cores that make up core 845. The second core 42 has a magnetic permeability M2 that is not the smallest magnetic permeability M1 in core 845. The third core 43 has a magnetic permeability M3 that is not the smallest magnetic permeability M1 in the core 845. Therefore, the core that has a magnetic permeability that is not the smallest magnetic permeability in the core 845 is the second core 42, the third core 43, or both the second core 42 and the third core 43.

[0100] The second core 42 and the third core 43 in the core 845 can be considered to be a core group having magnetic permeabilities M2 and M3 greater than the magnetic permeability M1 in comparison with the first core 41. Therefore, the second core 42 can be considered to include the third core 43 having a third magnetic permeability M3 greater than the second magnetic permeability M2. The third core 43 is disposed between the first core 41 and the second core 42.

[0101] A first boundary CB1 is located between the first core 41 and the third core 43. The first boundary CB1 is the boundary between the magnetic permeability M1 and the magnetic permeability M3. The magnetic permeability difference at the first boundary CB1 is relatively large. The magnetic permeability difference at the first boundary CB1 is the largest among the multiple magnetic permeability differences in the core 845. The magnetic permeability difference at the first boundary CB1 is referred to as a first magnetic permeability difference M13.

[0102] A second boundary CB2 is located between the second core 42 and the third core 43. The second boundary CB2 is the boundary between the magnetic permeability M2 and the magnetic permeability M3. The magnetic permeability difference at the second boundary CB2 is relatively small. The magnetic permeability difference at the second boundary CB2 is the smallest among the multiple magnetic permeability differences in the core 845. The magnetic permeability difference at the second boundary CB2 is referred to as a second magnetic permeability difference M32.

[0103] The first permeability difference M13 is greater than the second permeability difference M32. As a result, the leakage flux in the region from the first boundary CB1 where the first core 41 is located is less than the leakage flux in the regions from the first boundary CB1 where the second core 42 and the third core 43 are located.

[0104] The current measurement unit 30 is positioned closer to the region where the third core 43 and the second core 42 are located than the first boundary CB1. Furthermore, the current measurement unit 30 is positioned closer to the region where the second core 42 is located than the second boundary CB2. As a result, the above-described uneven distribution relationship is satisfied with respect to the second boundary CB2.

[0105] Alternatively, the current measurement unit 30 may be disposed between the first boundary CB1 and the second boundary CB2. In this alternative configuration, the maldistribution relationship is satisfied with respect to the first boundary CB1. From the viewpoint of suppressing the influence of leakage magnetic flux from the first core 41 on the current measurement unit 30, it is desirable that the above-described maldistribution relationship be satisfied with respect to the second boundary CB2. However, even if the maldistribution relationship with respect to the first boundary CB1 is satisfied, at least the effect of suppressing the influence caused by leakage magnetic flux from the first core 41 is achieved.

[0106] In this embodiment, the core 845 defines a first boundary CB1 that separates the area where the first core 41 is located from the area where the third core 43 is located. The core 845 defines a second boundary CB2 that separates the area where the second core 42 is located from the area where the third core 43 is located. The current measurement unit 30 is positioned closer to the area where the third core 43 is located than the first boundary CB1. The current measurement unit 30 is positioned closer to the area where the second core 42 is located than the second boundary CB2.

[0107] A minimum distance D1 is formed between the first core 41 and the current measurement unit 30. A minimum distance D2 is formed between the second core 42 and the current measurement unit 30. Distance D2 is the distance in the x direction, i.e., the adjacent direction. A minimum distance D3 is formed between the third core 43 and the current measurement unit 30. Distances D1 and D3 are diagonal distances. Distance D1 is longer than distance D2. Distance D1 is longer than distance D3. Distance D2 is longer than distance D3. Distance D1 is the longest of the multiple distances defined by the core 845. Distance D2 is the shortest of the multiple distances defined by the core 845.

[0108] Distance D1 is the distance between the first core 41, where the magnetic permeability in the core 845 is the minimum, and the current measurement unit 30. Distance D2 is the distance between the second core 42, where the magnetic permeability in the core 845 is not the minimum, and the current measurement unit 30. Distance D3 is also the distance between the third core 43, where the magnetic permeability in the core 845 is not the minimum, and the current measurement unit 30. Distance D2 is shorter than distance D1. Distance D3 is shorter than distance D1. Distance D2 is shorter than distance D3.

[0109] In this embodiment as well, the above-described uneven distribution relationship and distance relationship are satisfied, and as a result, the effects based on the uneven distribution relationship and distance relationship are obtained.

[0110] Ninth Embodiment The relative orientation of the reactor unit 7 and the sensor unit 9 can be modified in various ways. For example, the adjacent orientation shown in FIG. 2 can be adopted. In this adjacent orientation, the reactor unit 7 and the sensor unit 9 are arranged so that the longitudinal direction (z direction) of the reactor unit 7 and the longitudinal direction (z direction) of the sensor unit 9 are parallel to each other and overlap in the adjacent direction (x direction). The adjacent direction (x direction) may be the horizontal direction as shown in the figure. The horizontal direction may be the horizontal direction. Alternatively, the adjacent direction (x direction) may be the vertical direction as shown in FIG. 9. The vertical direction may be the up-down direction. Furthermore, as shown in FIG. 8, the adjacent direction (x direction) may be a diagonal direction.

[0111] Furthermore, the reactor unit 7 and the sensor unit 9 may be arranged as in this ninth embodiment, which is a modification of the preceding embodiment as a basic form.

[0112] 12 shows a ninth embodiment. In this embodiment, the longitudinal direction (x direction) of the reactor unit 7 intersects with the longitudinal direction (y direction) of the sensor unit 9. The reactor unit 7 and the sensor unit 9 are arranged so that one end face of the reactor unit 7 in the longitudinal direction overlaps with the sensor unit 9 in the adjacent direction (x direction). In this embodiment, the influence of leakage magnetic flux between the reactor element 40 arranged at one end of the reactor unit 7 in the longitudinal direction and the current measurement unit 30 of the sensor unit 9 is suppressed.

[0113] Tenth Embodiment This embodiment is a modification of the preceding embodiment as a basic form. The shield member exemplified in this embodiment can also be used in the other embodiments.

[0114] 13 shows a tenth embodiment. An electromagnetic shielding member that blocks linear transmission of magnetic flux is disposed between the reactor unit 7 and the sensor unit 9. The shielding member is provided by the housing 20 of the power control device 2.

[0115] The housing 20 includes an outer wall member 21 that provides an outer shell. The housing 20 has a partition wall A22 that extends from the outer wall member 21. The partition wall A22 is integrally formed from a common material that is continuous with the outer wall member 21. Alternatively, the partition wall A22 may be provided by a member separate from the outer wall member 21.

[0116] The housing 20 and the partition wall A22 are electromagnetic shielding members that prevent the penetration of magnetic flux. The housing 20 and the partition wall A22 are made of a ferromagnetic material such as an electromagnetic steel plate. Alternatively, the housing 20 and the partition wall A22 may be made of a conductive material that functions as an electromagnetic shielding member by generating eddy currents. For example, the housing 20 and the partition wall A22 are made of an aluminum alloy. Alternatively, the housing 20 and the partition wall A22 may be provided by a member in which an electromagnetic steel plate is embedded in an aluminum alloy body.

[0117] A boundary CB can be assumed between the first core 41 and the second core 42. The sensor unit 9 is disposed closer to the region where the first core 41 is located than the boundary CB. In this case, if leakage magnetic flux from the first core 41 were to reach the current measurement unit 30 in a linear manner, the influence of the leakage magnetic flux would be strongly observed. However, in this embodiment, the partition wall A22 serves as a shielding member, thereby suppressing the influence of the leakage magnetic flux from the first core 41.

[0118] The partition wall A22 is positioned between the reactor unit 7 and the sensor unit 9. The partition wall A22 extends over an area that completely covers the first core 41. The partition wall A22 extends from the outer wall member 21 to a height HS that exceeds the first core 41. The height HS of the partition wall A22 exceeds the boundary CB. The height HS of the partition wall A22 in the y direction is the height at which the partition wall A22 blocks linear access between the core 45 and the current measurement unit 30. The figure illustrates an imaginary line of sight VL directed from the current measurement unit 30 toward the core 45. In other words, the partition wall A22 is disposed between the core 45 and the current measurement unit 30 as a magnetic shield member that shields the first core 41 from the current measurement unit 30.

[0119] 13 shows the detour path of leakage magnetic flux that reaches the current measurement unit 30 from the core 45 of the reactor element 40. The length of the shortest detour path between the first core 41 and the current measurement unit 30 is distance D1. The length of the shortest detour path between the second core 42 and the current measurement unit 30 is distance D2. Distance D2 is shorter than distance D1. In this embodiment, the above-mentioned distance relationship is also satisfied. As a result, at least the effect resulting from the distance relationship is obtained.

[0120] Other Embodiments In the above embodiment, the current measurement unit 30 is primarily exemplified as an electrical component affected by leakage magnetic flux from the reactor element 40. However, the electrical component affected by leakage magnetic flux is not limited to the current measurement unit 30. The electrical component affected by leakage magnetic flux may be a functional component that does not include a conductive component that carries a large current. In this case, the electrical component affected by leakage magnetic flux may include various elements such as an inductance element, a control circuit, a bridge circuit, a sensor element that measures temperature, and a capacitance element. The conductive component that carries a large current may be a conductive component that carries a current that is controlled by the power control device 2. The electrical component affected by leakage magnetic flux may be a component that functions using the power supply voltage of the control system of the power control device 2. In many vehicles, for example, 12V or 24V components may be electrical components affected by leakage magnetic flux.

[0121] In the above embodiment, the reactor element 40 has been illustrated as having various core shapes. The core shape of the reactor element 40 is not limited to the illustrated shape. The reactor element 40 may have a distribution of magnetic permeability within an integrally molded core formed from a continuous material. In this case, a portion of the integrally molded core having a magnetic permeability M1 corresponding to the first core 41 and a portion having a magnetic permeability M2 corresponding to the second core 42 can be found. Furthermore, even when the magnetic permeability changes gradually and continuously, a boundary can be found in the center of the change region.

[0122] The reactor unit 7 may include a magnetic shielding member to reduce leakage magnetic flux to the outside. Even in such a configuration, the above-described embodiments contribute to suppressing the effects of leakage magnetic flux on electrical components.

[0123] The disclosure in this specification and drawings, etc. is not limited to the exemplified embodiments. The disclosure encompasses the exemplified embodiments and variations thereon by those skilled in the art. For example, the disclosure is not limited to the combinations of parts and / or elements shown in the embodiments. The disclosure can be implemented in various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure encompasses the omission of parts and / or elements from the embodiments. The disclosure encompasses the substitution or combination of parts and / or elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments. Some disclosed technical scopes are defined by the claims, and should be interpreted as including all modifications within the meaning and scope equivalent to the claims.

[0124] The disclosure in the specification, drawings, etc. is not limited by the claims. The disclosure in the specification, drawings, etc. encompasses the technical ideas described in the claims, and extends to more diverse and broader technical ideas than the technical ideas described in the claims. Therefore, various technical ideas can be extracted from the disclosure in the specification, drawings, etc. without being bound by the claims.

[0125] (Disclosure of Technical Ideas) This specification discloses multiple technical ideas described in the following multiple clauses. Some clauses may be described in a multiple dependent form, with the subsequent clause alternatively referring to the preceding clause. Furthermore, some clauses may be described in a multiple dependent form, with the subsequent clause referring to another multiple dependent clause. These multiple dependent clauses define multiple technical ideas.

[0126] (Technical Idea 1) A power control device (2) for converting electric power, comprising: a conductive member (2a) for flowing a current to be converted; a reactor element (40) having a coil (46) electrically connected to the conductive member and a core (45) for passing magnetic flux induced in the coil; and an electrical component (30) in the power control device that is affected by leakage magnetic flux from the core, wherein the core includes at least a first core (41) having a first magnetic permeability (M1) and a second core having a second magnetic permeability (M2) greater than the first magnetic permeability, and the core and the electrical component are arranged such that a first distance (D1) as a path of magnetic flux is formed between the first core and the electrical component, and a second distance (D2) as a path of magnetic flux is formed between the second core and the electrical component, and the power control device satisfies a distance relationship (D1>D2) in which the second distance is shorter than the first distance.

[0127] (Technical Concept 2) The power control device according to Technical Concept 1, wherein the reactor element and the electrical component are arranged adjacent to each other in the power control device.

[0128] (Technical Idea 3) A power control device according to Technical Idea 1 or Technical Idea 2, wherein the core defines a boundary (CB, CB1) that separates an area where the first core is located from an area where the second core is located, and the electrical components are biased toward the area where the second core is located relative to the boundary.

[0129] (Technical Idea 4) A power control device according to any one of Technical Ideas 1 to 3, wherein the second core is disposed between the first core and the electrical component, and a linear path from the first core to the electrical component is prevented.

[0130] (Technical Concept 5) The power control device according to any one of Technical Concepts 1 to 4, wherein the second core includes a third core (43) having a third magnetic permeability greater than the second magnetic permeability.

[0131] (Technical Concept 6) The power control device according to Technical Concept 5, wherein the third core is disposed between the first core and the second core.

[0132] (Technical Idea 7) A power control device according to Technical Idea 6, wherein the core defines a first boundary (CB1) that separates the area where the first core is located from the area where the third core is located, and a second boundary (CB2) that separates the area where the second core is located from the area where the third core is located, and the electrical components are biased toward the side of the area where the third core is located from the first boundary, or toward the side of the area where the second core is located from the second boundary.

[0133] (Technical Idea 8) A power control device according to any one of Technical Ideas 1 to 7, wherein a magnetic shielding member (A22) is arranged between the core and the electrical component to cover and hide the first core from the electrical component.

[0134] (Technical Idea 9) A power control device according to any one of Technical Ideas 1 to 8, wherein the electrical component is a circuit (34a) that is affected by the leakage magnetic flux, or a magnetic body (33a) that is affected by the leakage magnetic flux, or the power control device includes both the circuit and the magnetic body.

[0135] (Technical Idea 10) The power control device according to any one of Technical Ideas 1 to 9, wherein the electrical component is an electromagnetic current measuring unit (30) that detects magnetic flux resulting from a current flowing through the conductive member.

Claims

1. A power control device (2) for converting electric power, comprising: a conductive member (2a) for passing a current to be converted; a reactor element (40) having a coil (46) electrically connected to the conductive member and a core (45) through which magnetic flux induced in the coil passes; and an electrical component (30) that is an electrical component in the power control device and is affected by leakage magnetic flux from the core, the core including at least a first core (41) having a first magnetic permeability (M1) and a second core having a second magnetic permeability (M2) greater than the first magnetic permeability, the core and the electrical component being arranged such that a first distance (D1) as a path of magnetic flux is formed between the first core and the electrical component, and a second distance (D2) as a path of magnetic flux is formed between the second core and the electrical component, and the core and the electrical component are arranged such that a distance relationship (D1>D2) is satisfied in which the second distance is shorter than the first distance.

2. The power control device according to claim 1, wherein the reactor element and the electrical component are disposed adjacent to each other in the power control device.

3. A power control device as described in claim 1 or claim 2, wherein the core defines a boundary (CB, CB1) that separates an area in which the first core is located from an area in which the second core is located, and the electrical components are positioned biased toward the side of the boundary in which the second core is located.

4. A power control device as described in claim 1 or claim 2, wherein the second core is arranged between the first core and the electrical component, preventing a straight line from reaching the electrical component from the first core.

5. A power control device as claimed in claim 1 or 2, wherein the second core includes a third core (43) having a third permeability greater than the second permeability.

6. The power control device according to claim 5, wherein the third core is disposed between the first core and the second core.

7. A power control device as described in claim 6, wherein the core defines a first boundary (CB1) that separates an area in which the first core is located from an area in which the third core is located, and a second boundary (CB2) that separates an area in which the second core is located from an area in which the third core is located, and the electrical components are arranged biased toward the side of the area in which the third core is located from the first boundary, or toward the side of the area in which the second core is located from the second boundary.

8. A power control device according to claim 1 or 2, wherein a magnetic shielding member (A22) is disposed between the core and the electrical components to cover and conceal the first core from the electrical components.

9. A power control device as described in claim 1 or claim 2, wherein the electrical component comprises: a circuit (34a) that is affected by the leakage magnetic flux; or a magnetic body (33a) that is affected by the leakage magnetic flux; or both the circuit and the magnetic body.

10. A power control device according to claim 1 or 2, wherein the electrical component is an electromagnetic current measuring section (30) that detects magnetic flux resulting from a current flowing through the conductive member.

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