JP7308400B2 - POWER CONVERSION SYSTEM, POWER CONVERTER, CABLE SUPPORTER, ESTIMATION METHOD, AND PROGRAM - Google Patents

Description

The present disclosure relates generally to power conversion systems, power converters, cable supports, estimation methods, and programs. More specifically, the present disclosure relates to a power conversion system for charging a storage battery of a mobile object, a power converter and cable support used in the power conversion system, an estimation method in the power conversion system, and a program.

Patent Literature 1 discloses a power conversion system to which an electric vehicle equipped with a storage battery is connected. This power conversion system includes a power conversion device (power converter) and a connector connected to the power conversion device via a cable. A power conversion device has a main circuit that performs power conversion during charging and discharging of a storage battery. The connector forms a power supply path between the power converter and the storage battery by being attached to the inlet of the electric vehicle.

JP 2015-89220 A

An object of the present disclosure is to provide a power conversion system, a power converter, a cable support, an estimation method, and a program that can improve the accuracy of estimating the connector voltage applied to the connector.

A power conversion system according to one aspect of the present disclosure includes a power converter. The power converter is provided between a storage battery of a mobile body and an electric power system, and is capable of adjusting DC power charged in the storage battery via a connector connected to the mobile body. The power converter has a voltage measuring section and a current measuring section. The voltage measurement unit measures voltage applied to a cable connected between the moving body and the power converter. The current measurement unit measures the current flowing through the cable. The power conversion system further includes a voltage estimation unit and a notification unit. The voltage estimating section estimates a connector voltage applied to the connector based on the measurement results of the voltage measuring section and the current measuring section. The notification unit notifies the moving object of the connector voltage estimated by the voltage estimation unit.

A power converter according to an aspect of the present disclosure is used in the above power conversion system. The power converter is provided between the storage battery and the power system, and is capable of adjusting the DC power charged to the storage battery through the connector. The power converter includes the voltage measurement section and the current measurement section.

A cable supporter according to an aspect of the present disclosure is used in the above power conversion system and supports the cable.The cable support includes the voltage estimator.

An estimation method according to an aspect of the present disclosure includes a voltage measurement step, a current measurement step, a voltage estimation step, and a notification step. The voltage measurement step is a step of measuring a voltage applied to a cable connected between the power converter and the mobile object. The power converter is provided between a storage battery of the moving body and an electric power system, and is capable of adjusting DC power charged in the storage battery through a connector connected to the moving body. The current measuring step is a step of measuring the current flowing through the cable. The voltage estimating step is a step of estimating a connector voltage applied to the connector based on each measurement result of the voltage measuring step and the current measuring step. The notification step is a step of notifying the moving body of the connector voltage estimated in the voltage estimation step.

A program according to an aspect of the present disclosure causes one or more processors to execute the above estimation method.

The present disclosure has the advantage of improving the accuracy of estimating the connector voltage applied to the connector.

FIG. 1 is a schematic diagram showing an overall configuration including a power conversion system according to one embodiment of the present disclosure. FIG. 2 is a schematic diagram showing the configuration of the same power conversion system. FIG. 3 is a schematic diagram showing an installation example of the power conversion system same as above. FIG. 4 is a flow chart showing an example of the operation of the power conversion system; FIG. 5 is a schematic diagram showing the configuration of a power conversion system of a modification.

(1) Overview The power conversion system 100 of the present embodiment is installed in, for example, a residential facility such as a detached house or collective housing, or a non-residential facility such as an office, store, or nursing care facility. The power conversion system 100 is a system for supplying power (charging) to the storage battery 31 of the moving body 3 at these facilities (see FIG. 1). In this embodiment, as an example, a case where the power conversion system 100 is introduced into a house H1, which is a detached house, will be described.

The moving body 3 includes a power unit such as an electric motor (motor), and a storage battery 31 as a power source that supplies electric power to the power unit. The moving body 3 converts electrical energy (electric power) input from the storage battery 31 into mechanical energy (driving force) in the power section, and moves using this mechanical energy. The moving object 3 has a power control circuit 32 . The power control circuit 32 charges the storage battery 31 with charging power that does not exceed a predetermined maximum value.

The mobile object 3 is a vehicle 30 here. The vehicle 30 is, for example, an electric vehicle that runs using electrical energy stored in a storage battery 31 . An “electric vehicle” as used in the present disclosure is, for example, an electric vehicle that runs on the output of an electric motor, or a plug-in hybrid vehicle that runs on a combination of the output of an engine and the output of an electric motor. The electric vehicle may be a senior car, a two-wheeled vehicle (electric motorcycle), a tricycle, an electric bicycle, or the like.

The power converter system 100 includes a first power converter 11 and a second power converter 12, as shown in FIG. In the following description, the 1st power converter 11 and the 2nd power converter 12 may be collectively called the "power converter 1." Moreover, in the following description, the 2nd power converter device 12 may be called the "power converter 1."

The first power conversion device 11 converts AC power input from the power system 4 into DC power and outputs the DC power to the DC bus DB1. That is, the first power conversion device 11 has a function of an AC/DC converter that converts input AC power into DC power of a predetermined magnitude and outputs the DC power.

The second power conversion device 12 converts the DC power input from the DC bus DB1 into charging power of the storage battery 31 of the moving body 3 and outputs the charging power. That is, the second power conversion device 12 has a function of a DC/DC converter that converts input DC power into DC power of a predetermined magnitude and outputs the DC power. That is, the power converter 1 is provided between the storage battery 31 of the moving body 3 and the electric power system 4, and is connected to the moving body 3 via a connector CN1 (described later) to charge the storage battery 31 with direct current. Adjustable power.

In this embodiment, the power conversion system 100 further includes a cable supporter 2 . Although the cable supporter 2 is included in the power conversion system 100 in this embodiment, it may not be included in the power conversion system 100 .

Cable supporter 2 supports cable C1. The cable C<b>1 is connected between the mobile object 3 and the second power conversion device 12 to form a power supply path between the storage battery 31 and the second power conversion device 12 . A connector CN1 is attached to the tip of the cable C1. The connector CN1 is configured to be connectable to the inlet 34 of the mobile body 3 . That is, the DC power (charge power) output from the second power conversion device 12 is supplied to the storage battery 31 via the cable C1 supported by the cable supporter 2 in a state where the connector CN1 is connected to the inlet 34. will be

A “cable” as used in the present disclosure refers to a linear member in which one or more electric wires are protected by a sheath (outer cover). In addition, the "electric wire" referred to in the present disclosure may include an insulated electric wire in which an electric conductor is covered with an insulator, in addition to a bare electric wire that is only an electric conductor.

The support of the cable C1 by the cable supporter 2 referred to in the present disclosure is, for example, by the user U1 hooking the cable C1 so as not to obstruct the passage of the user U1 (see FIG. 3) when the connector CN1 is not in use. It does not mean only the mode of temporarily supporting C1. That is, the support of the cable C1 by the cable supporter 2 referred to in the present disclosure also means to permanently support the cable C1 without attachment/detachment by the user U1 in principle.

Here, in the present embodiment, the power converter 1 has a voltage measuring section 124 and a current measuring section 125 .

The voltage measurement unit 124 measures the voltage V1 (see FIG. 2) applied to the cable C1 connected between the mobile object 3 and the power converter 1. FIG. The current measurement unit 125 measures the current I1 (see FIG. 2) flowing through the cable C1.

Moreover, in this embodiment, the power conversion system 100 further includes a voltage estimation unit 126 and a notification unit 127 . The voltage estimation unit 126 estimates the connector voltage V0 (see FIG. 2) applied to the connector CN1 based on the measurement results of the voltage measurement unit 124 and the current measurement unit 125 respectively. The notification unit 127 notifies the mobile body 3 of the connector voltage V0 estimated by the voltage estimation unit 126 .

In this embodiment, the current measurement unit 125 measures the current I1 flowing through the cable C1. Therefore, in the present embodiment, the voltage estimator 126 estimates the connector voltage V0 in consideration of the voltage drop in the cable C1 calculated from the wiring impedance of the cable C1 and the current I1 flowing through the cable C1. Is possible. Therefore, in this embodiment, there is an advantage that the estimation accuracy of the connector voltage V0 applied to the connector CN1 is improved.

(2) Details Hereinafter, the power conversion system 100 of the present embodiment will be described in detail with reference to the drawings.

(2.1) Overall Configuration First, the overall configuration including the power conversion system 100 will be described with reference to FIG. In this embodiment, the power conversion system 100 realizes the function as the power conversion system 100 by cooperating with the device control device 5 installed inside the house H1.

The power converter 1 and the equipment control device 5 of the power conversion system 100 are configured to be able to communicate with each other. In the present disclosure, “communicable” means that information can be exchanged directly or indirectly via a network, a repeater, or the like, by an appropriate communication method such as wired communication or wireless communication. That is, the power converter 1 and the device control device 5 can exchange information with each other. In this embodiment, the power converter 1 and the device control device 5 can communicate bidirectionally with each other, and information is transmitted from the power converter 1 to the device control device 5, and power conversion is performed from the device control device 5. Both sending information to the device 1 are possible.

The device control device 5 is a device that controls at least the power converter 1 . Device control device 5 outputs to power converter 1 a charge start signal for instructing the start of charging and a charge stop signal for instructing the stop of charging, whereby movement by power converter 1 is controlled. It controls the start and stop of charging of the storage battery 31 of the body 3 . Therefore, for example, when the user U1 performs a predetermined operation on the device control device 5, the power converter 1 is instructed to start charging the storage battery 31 or to stop charging the storage battery 31. Is possible.

In this embodiment, the device control device 5 is connected to a network such as the Internet via a router. Therefore, the device control device 5 can communicate with the information terminal possessed by the user U1 via a router or a router and a network. The information terminal is, for example, a smart phone, a tablet terminal, or a personal computer. Therefore, the user U1 can instruct to start charging the storage battery 31 or to stop charging the storage battery 31 not only by directly operating the device control device 5 but also by operating the information terminal. is possible.

The power converter 1 is charging equipment for charging the storage battery 31 of the mobile body 3 . In this embodiment, the power converter 1 is installed inside the house H1. A cable C1 is connected to the power converter 1 . The tip of the cable C1 has a connector CN1 detachably connected to the inlet 34 of the moving body 3. As shown in FIG. Since the power converter 1 is connected to the moving body 3 via the cable C1 while the connector CN1 is connected to the inlet 34, power can be supplied to the storage battery 31 of the moving body 3 via the cable C1. It becomes possible to charge the storage battery 31 .

Further, in this embodiment, the power converter 1 is also a discharging facility having a function of discharging from the storage battery 31 of the moving object 3 via the cable C1 while the connector CN1 is connected to the inlet 34. Therefore, in this embodiment, a V2H (Vehicle To Home) system can be constructed by outputting the discharged power of the storage battery 31 of the moving body 3 to the load (including the distribution board) of the house H1.

The moving body 3 includes a storage battery 31 , a power control circuit 32 and an ECU (Electronic Control Unit) 33 . The power control circuit 32 is a circuit that receives power from the power converter 1 and charges the storage battery 31 . In this embodiment, the power control circuit 32 has a function of discharging the storage battery 31 in addition to a function of charging the storage battery 31 . The EUC 33 controls the power control circuit 32 based on a signal (here, as an example, a signal based on the CHAdeMO (registered trademark) standard) transmitted via a communication line L2 (described later) of the cable C1.

(2.2) Power Conversion System Next, the power conversion system 100 will be described with reference to FIGS. 1 to 3. FIG. The power converter system 100 includes a first power converter 11 and a second power converter 12 as the power converter 1 and a cable supporter 2 .

The 1st power converter 11 is provided with the main circuit 111, the control circuit 112, and the communication part 113, as shown in FIG. In addition, in the first power conversion device 11, the main circuit 111, the control circuit 112, and the communication unit 113 are all accommodated in a rectangular parallelepiped housing 11A (see FIG. 3). In this embodiment, the housing 11A is installed inside the house H1, as shown in FIG.

The main circuit 111 is a bi-directional AC/DC converter, one end of which is connected to the power system 4, and the other end of which is connected to the main circuit of the second power conversion device 12 via a DC cable C2 having a DC bus DB1. 121. The main circuit 111 has, for example, a plurality of switching elements connected in a full bridge connection, and the plurality of switching elements are PWM (Pulse Width Modulation) controlled by the control circuit 112 to convert DC power to AC power or AC power. It converts electric power into DC power.

In this embodiment, the main circuit 111 has a function of converting AC power input from the power system 4 into DC power of a predetermined magnitude and outputting the DC power to the second power converter 12 . Further, in the present embodiment, the main circuit 111 has a function of converting the DC power output from the second power conversion device 12 into AC power of a predetermined magnitude and outputting it to the power system 4 . In other words, the first power converter 11 has a function of converting DC power input from the DC cable C2 (DC bus DB1) into AC power and outputting the AC power to the power system 4 .

The control circuit 112 is at least partially composed of a microcontroller having one or more processors and memory. In other words, at least part of the control circuit 112 is implemented in a computer system having one or more processors and memory, and the one or more processors execute a program stored in the memory so that the computer system It functions as part of the control circuit 112 . Although the program is pre-recorded in the memory of the control circuit 112 here, it may be provided through an electric communication line such as the Internet or recorded in a non-temporary recording medium such as a memory card. The control circuit 112 also has a driver for driving the switching elements of the main circuit 111 . The control circuit 112 may be configured by, for example, an FPGA (Field-Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

The control circuit 112 receives a command from the device control device 5 or the information terminal via the communication unit 113 to control the main circuit 111 to start charging the storage battery 31 or stop charging the storage battery 31. It has the function to In the present embodiment, the control circuit 112 controls the main circuit 111 to convert the DC power from the second power conversion device 12 into AC power to convert the DC power from the second power converter 12 to the load ( It also has a function to output to the distribution board).

The communication unit 113 has a function of communicating with the device control device 5 . As a communication method between the communication unit 113 and the device control device 5, an appropriate communication method such as wireless communication or wired communication is adopted. In this embodiment, as an example, the communication method between the communication unit 113 and the device control device 5 is wired communication conforming to a communication standard such as a wired LAN (Local Area Network). A communication protocol for communication between the communication unit 113 and the device control device 5 is, for example, Ethernet (registered trademark) or ECHONET Lite (registered trademark).

The communication unit 113 also has a function of communicating with a communication unit 123 (described later) of the second power converter 12 . As a communication method between the communication unit 113 and the communication unit 123 of the second power conversion device 12, an appropriate communication method such as wireless communication or wired communication is adopted. In this embodiment, as an example, the communication unit 113 performs wire communication with the communication unit 123 of the second power converter 12 via the communication line L2 of the DC cable C2.

The 2nd power converter 12 is provided with the main circuit 121, the control circuit 122, and the communication part 123, as shown in FIG. In addition, in the second power conversion device 12, the main circuit 121, the control circuit 122, and the communication unit 123 are all accommodated in a rectangular parallelepiped housing 12A (see FIG. 3). In this embodiment, the housing 12A is installed inside the house H1, as shown in FIG.

The main circuit 121 is a bidirectional DC/DC converter, one end of which is connected to the first cable C11, and the other end of which is connected to the main circuit 111 of the first power converter 11 via the DC cable C2. ing. The main circuit 121 has, for example, one or more switching elements, and the one or more switching elements are PWM-controlled by the control circuit 122 to adjust and output the input DC power.

In this embodiment, the main circuit 121 converts the DC power output from the first power conversion device 11 into DC power of a predetermined magnitude, and outputs the power to the storage battery 31 via the first cable C11 and the connector CN1. have. Further, in the present embodiment, the main circuit 121 converts the DC power discharged from the storage battery 31 through the first cable C11 and the connector CN1 into DC power of a predetermined magnitude, and outputs the DC power to the first power conversion device 11. It has the function to In other words, the second power conversion device 12 has a function of adjusting the discharge power (DC power) discharged from the storage battery 31 and outputting it to the DC bus DB1.

The control circuit 122 is configured at least in part by a microcontroller having one or more processors and memory. In other words, at least part of the control circuit 122 is implemented in a computer system having one or more processors and memory, and the one or more processors execute a program stored in the memory so that the computer system It functions as part of the control circuit 122 . Although the program is previously recorded in the memory of the control circuit 122 here, it may be provided through an electric communication line such as the Internet or recorded in a non-temporary recording medium such as a memory card. Also, the control circuit 122 has a driver for driving one or more switching elements of the main circuit 121 . The control circuit 122 may be configured by FPGA, ASIC, or the like, for example.

The control circuit 122 receives a command from the device control device 5 or the information terminal via the communication unit 123 and the communication unit 113 of the first power converter 11 to control the main circuit 121 and start charging the storage battery 31. and stop charging of the storage battery 31 . In this embodiment, the control circuit 122 controls the main circuit 121 to adjust the discharge power (DC power) from the storage battery 31 and output it to the first power conversion device 11, for example, at the time of a power failure in the power system 4. It also has functions.

The communication unit 123 has a function of communicating with the communication unit 113 of the first power converter 11 . As a communication method between the communication unit 123 and the communication unit 113 of the first power conversion device 11, an appropriate communication method such as wireless communication or wired communication is adopted. In this embodiment, as an example, the communication unit 123 performs wired communication with the communication unit 113 of the first power converter 11 via the communication line L2 of the DC cable C2.

The communication unit 123 also has a function of communicating with the mobile unit 3 . As a communication method between the communication unit 123 and the moving body 3, an appropriate communication method such as wireless communication or wired communication is adopted. In this embodiment, as an example, the communication unit 123 performs wire communication with the moving body 3 via the communication line L2 of the cable C1. In the present embodiment, as an example, the communication unit 123 uses signals based on at least the ChadeMO (registered trademark) standard to perform communication for confirming the connection between the power converter 1 and the moving object 3, confirming the state of the moving object 3, and the like. I do.

The cable supporter 2 supports part of the cable C1, as shown in FIG. Further, in the cable supporter 2, part of the cable C1 is supported by being housed in a rectangular parallelepiped housing 2A (see FIG. 3). In this embodiment, the housing 2A is installed in the parking space A1 for the moving body 3 outside the house H1, as shown in FIG. In other words, the cable supporter 2 is installed independently on the ground (here, the parking space A1).

In this embodiment, the cable C1 has a first cable C11 and a second cable C12. A first cable C11 is connected between the mobile body 3 and the cable supporter 2 . The second cable C12 is of a different type from the first cable C11 and is connected between the cable support 2 and the second power converter 12 . That is, in the embodiment, the first cable C11 and the second cable C12 are of different types.

In the present embodiment, except for the case where two cables obtained by cutting one cable C1 are used as the first cable C11 and the second cable C12, respectively, basically the first cable C11 and the second cable It can be said that C12 is of a different type. Specifically, it can be said that the first cable C11 and the second cable C12 are of different types due to their different diameters. In addition, it can be said that the first cable C11 and the second cable C12 are of different types because the numbers of wires included therein are different. In addition, it can be said that the first cable C11 and the second cable C12 are of different types when the structures, materials, or manufacturers of the cables are different from each other.

In this embodiment, the first cable C11 is, for example, a cabtire cable. Moreover, in this embodiment, the 2nd cable C12 is a crosslinked polyethylene insulation vinyl sheath cable (CV cable) as an example. Further, in the present embodiment, both the first cable C11 and the second cable C12 include one or more (here, two) power lines L1 and one or more (here, a plurality of) communication lines L2. have. Furthermore, in this embodiment, the DC cable C2 is a CV cable like the second cable C12, and has one or more power lines L1 and one or more communication lines L2.

The cable supporter 2 (power conversion system 100) further includes a connecting portion 20 that connects the first cable C11 and the second cable C12 to each other. In this embodiment, the connecting portion 20 is housed inside the housing 2A of the cable supporter 2 . That is, the connecting portion 20 is provided inside the cable support 2 .

In this embodiment, the connecting portion 20 has a first terminal 21 to which the first cable C11 is connected and a second terminal 22 to which the second cable C12 is connected. That is, in the present embodiment, the first cable C<b>11 is fixed (supported) to the cable supporter 2 by connecting one end of the first cable C<b>11 to the first terminal 21 . The second cable C12 is fixed (supported) to the cable supporter 2 by connecting one end of the second cable C12 to the second terminal 22 .

The first terminal 21 and the second terminal 22 are connected via an electric circuit 23 . The electric circuit 23 can connect, for example, one or more power lines L1 and one or more communication lines L2 of the first cable C11 to one or more power lines L1 and one or more communication lines L2 of the second cable C12. It is a conversion circuit that converts electrical connections. Of course, the electric circuit 23 interconnects the one or more power lines L1 and the one or more communication lines L2 of the first cable C11 and the one or more power lines L1 and the one or more communication lines L2 of the second cable C12. It may be a mere electrical conductor.

In this embodiment, as shown in FIG. 3, between the cable supporter 2 and the first power converter 11, part of the cable C1 is laid underground. Similarly, between the first power conversion device 11 and the second power conversion device 12, part of the DC cable C2 is laid underground. In the ground, the cable C1 is passed through a pipe C3 such as a metal wire conduit. The hardness of the pipe C3 is higher than the hardness of the sheath (outer covering) of the cable C1.

2, the power converter 1 (here, the second power conversion device 12) includes a voltage measurement unit 124, a current measurement unit 125, a voltage estimation unit 126, a notification unit 127, an input a portion 128; That is, in this embodiment, the voltage estimator 126 is provided in the power converter 1 .

The voltage measurement unit 124 measures the voltage V1 applied to the cable C1. In the present embodiment, the voltage measurement unit 124 applies the voltage V1 applied between the pair of power lines L1 included in the second cable C12 of the cable C1 connected to the second power converter 12 to the cable C1. measured as the voltage V1 applied. Information on the voltage V<b>1 measured by the voltage measurement unit 124 is input to the voltage estimation unit 126 .

The current measurement unit 125 measures the current I1 flowing through the cable C1. In this embodiment, the current measuring unit 125 measures the current I1 flowing through the pair of power lines L1 included in the second cable C12 connected to the second power converter 12 among the cables C1. The current I1 is measured as a charging current that flows from the power converter 1 to the storage battery 31 when the storage battery 31 is charged. Further, the current I1 is measured as a discharge current flowing from the storage battery 31 to the power converter 1 when the storage battery 31 is discharged. Information on the current I<b>1 measured by the current measuring unit 125 is input to the voltage estimating unit 126 .

The voltage estimation unit 126 estimates the connector voltage V0 applied to the connector CN1 based on the measurement results of the voltage measurement unit 124 and the current measurement unit 125 respectively. Specifically, the voltage estimation unit 126 estimates the connector voltage V0 by adding or subtracting the voltage drop in the cable C1 to or from the voltage V1 applied to the cable C1 measured by the voltage measurement unit 124. do.

The voltage drop can be calculated by multiplying the wiring impedance of the cable C1 by the current I1 measured by the current measuring unit 125. FIG. Here, for example, when the length of the cable C1 and the impedance per unit length are known at the time of shipment of the power converter 1, the wiring impedance of the cable C1 can be stored in advance in the memory of the voltage estimation unit 126. good.

On the other hand, for example, when wiring the cable C1 during construction of the power conversion system 100, the length of the cable C1 to be wired and the impedance per unit length may be input to the input unit 128 (described later). In this case, the voltage estimation unit 126 calculates the wiring impedance of the cable C1 based on the information input to the input unit 128, and stores the calculated wiring impedance in the memory. That is, voltage estimating section 126 can estimate connector voltage V0 using the information input to input section 128 .

When charging the storage battery 31, the voltage estimation unit 126 calculates the connector voltage V0 by subtracting the voltage drop from the voltage V1 applied to the cable C1. On the other hand, when the storage battery 31 is discharged, the voltage estimator 126 calculates the connector voltage V0 by adding the voltage drop to the voltage V1 applied to the cable C1.

The notification unit 127 notifies the mobile body 3 of the connector voltage V0 estimated by the voltage estimation unit 126 . In this embodiment, the notification unit 127 transmits the estimation result of the connector voltage V0 to the ECU 33 of the moving body 3 via the communication line L2 and the connector CN1 included in the cable C1.

The input unit 128 is an interface that can be operated by the user U1 (including the installer), and can input at least information about the second cable C12. In this embodiment, the input unit 128 can input information about the cable C1. Here, "information about the second cable (or cable)" includes, for example, the overall wiring impedance of the second cable C12 (or cable C1), the length of the second cable C12 (or cable C1), and wiring impedance per unit length of the second cable C12 (or cable C1). In addition, "information about the second cable (or cable)" may include, for example, the cross-sectional area or diameter (outer diameter) of the second cable C12 (or cable C1). Information input to the input unit 128 is input to the voltage estimation unit 126 .

(3) Operation An example of operation for estimating connector voltage V0 in power conversion system 100 will be described below with reference to FIG. The following operations are performed in real time while the storage battery 31 is being charged or discharged.

First, the voltage measurement unit 124 measures the voltage V1 applied to the cable C1 (S1). Next, the current measurement unit 125 measures the current I1 flowing through the cable C1 (S2). The order of the processes S1 and S2 may be reversed. Next, the voltage estimating unit 126 uses the wiring impedance of the cable C1 stored in the memory and the measurement result of the current I1 by the current measuring unit 125 to calculate the voltage drop in the cable C1 (S3 ). Then, the voltage estimation unit 126 estimates the connector voltage V0 using the measurement result of the voltage V1 by the voltage measurement unit 124 and the calculated voltage drop of the cable C1 (S4). After that, the notification unit 127 notifies the estimation result of the connector voltage V0 estimated by the voltage estimation unit 126 to the ECU 33 of the mobile body 3 via the communication line L2 of the cable C1 and the connector CN1 (S5). At this time, the notification unit 127 also notifies the ECU 33 of the measurement result of the current I<b>1 measured by the current measurement unit 125 .

The ECU 33 of the mobile body 3 monitors whether or not the connector voltage V0 deviates from a predetermined range. The ECU 33 also monitors whether the current I1 deviates from a predetermined range. Then, when at least one of the connector voltage V0 and the current I1 deviates from the predetermined range, the ECU 33 determines that there is an abnormality in the connection operation between the mobile body 3 and the power conversion system 100, and determines whether the storage battery 31 is charged or discharged. A control signal requesting a stop is sent to the power conversion system 100 .

(4) Advantages As described above, in the present embodiment, the current measurement unit 125 measures the current I1 flowing through the cable C1. Therefore, in the present embodiment, the voltage estimator 126 estimates the connector voltage V0 in consideration of the voltage drop in the cable C1 calculated from the wiring impedance of the cable C1 and the current I1 flowing through the cable C1. Is possible. Therefore, in this embodiment, there is an advantage that the estimation accuracy of the connector voltage V0 applied to the connector CN1 is improved.

This embodiment is particularly effective when part of the cable C1 is changeable. That is, when the cable C1 is fixed at the time of shipment of the power converter 1 and at the time of construction of the power conversion system 100, the voltage drop in the cable C1 hardly changes, so the estimation accuracy of the connector voltage V0 has little impact on On the other hand, when part of the cable C1 (for example, the second cable C12) is changed during construction of the power conversion system 100, the voltage drop in the cable C1 fluctuates according to the changed cable C1. It may affect the estimation accuracy of the voltage V0.

Therefore, in the present embodiment, the voltage estimation unit 126 uses the measurement result of the current I1 measured by the current measurement unit 125 and the wiring impedance of the cable C1 to It is possible to calculate the voltage drop at Therefore, in this embodiment, it is possible to accurately estimate the connector voltage V0 even when the cable C1 is changed.

(5) Modifications The above-described embodiment is just one of various embodiments of the present disclosure. The above-described embodiments can be modified in various ways according to design and the like as long as the object of the present disclosure can be achieved. Also, functions similar to those of the power conversion system 100 may be embodied by an estimation method, a (computer) program, a non-temporary recording medium recording the program, or the like.

An estimation method according to one aspect includes a voltage measurement step, a current measurement step, a voltage estimation step, and a notification step. The voltage measurement step is a step of measuring the voltage V1 applied to the cable C1 connected between the power converter 1 and the moving body 3. FIG. The power converter 1 is provided between the storage battery 31 of the moving body 3 and the power system 4 and can adjust DC power charged in the storage battery 31 via a connector CN1 connected to the moving body 3 . The current measurement step is a step of measuring the current flowing through the cable C1. The voltage estimation step is a step of estimating the connector voltage V0 applied to the connector CN1 based on the measurement results of the voltage measurement step and the current measurement step. The notification step is a step of notifying the moving body 3 of the connector voltage V0 estimated in the voltage estimation step. Also, a program according to one aspect causes one or more processors to execute the estimation method described above.

Modifications of the above-described embodiment are listed below. Modifications described below can be applied in combination as appropriate.

The power conversion system 100 in the present disclosure includes a computer system in the voltage estimator 126, for example. A computer system is mainly composed of a processor and a memory as hardware. The function of the voltage estimator 126 in the present disclosure is realized by the processor executing a program recorded in the memory of the computer system. The program may be recorded in advance in the memory of the computer system, may be provided through an electric communication line, or may be recorded in a non-temporary recording medium such as a computer system-readable memory card, optical disk, or hard disk drive. may be provided. A processor in a computer system consists of one or more electronic circuits, including semiconductor integrated circuits (ICs) or large scale integrated circuits (LSIs). The integrated circuit such as IC or LSI referred to here is called differently depending on the degree of integration, and includes integrated circuits called system LSI, VLSI (Very Large Scale Integration), or ULSI (Ultra Large Scale Integration). In addition, a field-programmable gate array (FPGA) that is programmed after the LSI is manufactured, or a logic device capable of reconfiguring the bonding relationship inside the LSI or reconfiguring the circuit partitions inside the LSI may also be adopted as the processor. can be done. A plurality of electronic circuits may be integrated into one chip, or may be distributed over a plurality of chips. A plurality of chips may be integrated in one device, or may be distributed in a plurality of devices. A computer system, as used herein, includes a microcontroller having one or more processors and one or more memories. Accordingly, the microcontroller also consists of one or more electronic circuits including semiconductor integrated circuits or large scale integrated circuits.

In addition, it is not an essential configuration of voltage estimating section 126 that a plurality of functions of voltage estimating section 126 are integrated into one housing. The constituent elements of the voltage estimating section 126 may be distributed over a plurality of housings. Furthermore, at least part of the functions of the voltage estimator 126 may be implemented by, for example, a server device and cloud (cloud computing). Conversely, all functions of the voltage estimator 126 may be integrated into one housing as in the above-described embodiment.

In the above-described embodiments, the cable supporter 2 may have a cable voltage measuring section 129 as shown in FIG. In the power conversion system 100 of the modification shown in FIG. 5, the voltage estimation unit 126, the notification unit 127, and the input unit 128 are provided in the cable supporter 2 instead of the power converter 1 (here, the second power converter 12). is different from the power conversion system 100 of the above-described embodiment.

The cable voltage measurement unit 129 measures the voltage V2 applied to the first cable C11. In this modification, the cable voltage measuring unit 129 measures the voltage V2 applied between the pair of power lines L1 included in the first cable C11 as the voltage V2 applied to the first cable C11. Information on the voltage V2 measured by the cable voltage measuring unit 129 is input to the voltage estimating unit 126 .

In this modification, voltage estimator 126 estimates connector voltage V0 using the measurement result of cable voltage measurer 129 . Specifically, the voltage estimation unit 126 adds or subtracts the voltage drop in the first cable C11 to or from the voltage V2 applied to the first cable C11 measured by the cable voltage measurement unit 129. Estimate the connector voltage V0. The voltage drop can be calculated by multiplying the wiring impedance of the first cable C11 by the current I1 measured by the current measuring unit 125. FIG.

As described above, this modification has the advantage that if the first cable C11 is known, the connector voltage V0 can be estimated without using information about the second cable C12. Therefore, in this modified example, there is an advantage that it is possible to save the trouble of inputting information about the second cable C12. In addition, this modification has the advantage that it is possible to eliminate the possibility of affecting the estimation accuracy of the connector voltage V0 by erroneously inputting information regarding the second cable C12.

In the above-described embodiments, the input section 128 may not be provided in the power converter 1 and may be provided in the cable supporter 2 . When the input unit 128 is provided in the cable support 2, the information input to the input unit 128 is transmitted to the voltage estimation unit 126 of the second power converter 12 via the communication line L2 of the second cable C12. be done. Also, the input unit 128 may be realized by, for example, an information terminal (such as a smart phone) possessed by the user U1. In this case, the information input to the input unit 128 is transmitted to the voltage estimating unit 126 via a server via a network such as the Internet.

In the above-described embodiments, the power conversion system 100 (cable supporter 2) does not have to include the connecting section 20. FIG. In other words, the cable supporter 2 may support one cable C1 that connects the moving body 3 and the second power conversion device 12 in a continuous manner.

In the above-described embodiment, the power conversion system 100 can build a V2H system, but it does not have to. That is, the power conversion system 100 may be constructed only as a charging system that charges the storage battery 31 . In this case, in the power conversion system 100 , the power converter 1 only needs to have a power conversion function in one direction from the power system 4 to the storage battery 31 .

In the above-described embodiment, the cable supporter 2 may be provided with an operation unit for instructing the start and stop of charging of the storage battery 31 . In this case, the user U1 can instruct the start and stop of charging of the storage battery 31 by operating the operation unit without directly operating the device control device 5 . Further, the operating portion may be provided on the connector CN1 instead of the cable supporter 2. FIG.

In the above-described embodiment, the first power conversion device 11 and the second power conversion device 12 do not have to be configured separately from each other. That is, the first power converter 11 and the second power converter 12 may be housed in one housing as the power converter 1 .

In the above-described embodiments, the power converter 1 does not have to include the first power conversion device 11 . That is, the first power conversion device 11 does not have to be included in the components of the power conversion system 100 .

In the above-described embodiments, the cable support 2 can be marketed alone. That is, the cable supporter 2 is used in the power conversion system 100 to support the cable C1. Similarly, power converter 1 may be marketed alone. That is, the power converter 1 is used for the power conversion system 100 .

(summary)
As described above, the power conversion system (100) according to the first aspect includes the power converter (1) (here, the second power converter (12)). A power converter (1) is provided between a storage battery (31) of a mobile object (3) and a power system (4), and is connected to the mobile object (3) via a connector (CN1). The DC power charged to (31) can be adjusted. A power converter (1) has a voltage measuring section (124) and a current measuring section (125). A voltage measurement unit (124) measures a voltage (V1) applied to a cable (C1) connected between the mobile body (3) and the power converter (1). A current measuring unit (125) measures the current (I1) flowing through the cable (C1). The power conversion system (100) further comprises a voltage estimator (126) and a notifier (127). A voltage estimating section (126) estimates a connector voltage (V0) applied to the connector (CN1) based on the measurement results of the voltage measuring section (124) and the current measuring section (125). A notification unit (127) notifies the mobile body (3) of the connector voltage (V0) estimated by the voltage estimation unit (126).

This aspect has the advantage of improving the estimation accuracy of the connector voltage (V0) applied to the connector (CN1).

The power conversion system (100) according to the second aspect, in the first aspect, further includes a cable support (2) that supports the cable (C1). The cable support (2) has a connecting portion (20) to which a first cable (C11) and a second cable (C12) are connected. The first cable (C11) is a cable connected between the moving body (3) and the cable supporter (2) among the cables (C1). The second cable (C12) is a cable connected between the cable support (2) and the power converter (1) in the cable (C1).

According to this aspect, it is possible to accurately estimate the connector voltage (V0) even when the type or length of either the first cable (C11) or the second cable (C12) is changed. has the advantage of being

The power conversion system (100) according to the third aspect further comprises an input section (128) in the second aspect. The input unit (128) can input information about the second cable (C12). A voltage estimating section (126) estimates the connector voltage (V0) using the information input to the input section (128).

According to this aspect, at least when the second cable (C12) is changed, there is an advantage that the wiring impedance of the second cable (C12) after change can be referred to by the voltage estimator (126). .

In the power conversion system (100) according to the fourth aspect, in the second aspect, the cable supporter (2) includes a cable voltage measurement unit ( 129). A voltage estimator (126) estimates the connector voltage (V0) using the measurement result of the cable voltage measurement unit (129).

This aspect has the advantage that if the first cable (C11) is known, the connector voltage (V0) can be estimated without using information about the second cable (C12).

In the power conversion system (100) according to the fifth aspect, in any one of the first to fourth aspects, the voltage estimator (126) is provided in the power converter (1).

According to this aspect, there is an advantage that the measurement results of the voltage measuring section (124) and the current measuring section (125) can be referred to without being transmitted via the cable (C1) or the like.

A power converter (1) according to a sixth aspect is used in the power conversion system (100) according to any one of the first to fifth aspects.

This aspect has the advantage of improving the estimation accuracy of the connector voltage (V0) applied to the connector (CN1).

A cable supporter (2) according to a seventh aspect is used in the power conversion system (100) according to any one of the first to fifth aspects and supports cables (C1).

This aspect has the advantage of improving the estimation accuracy of the connector voltage (V0) applied to the connector (CN1).

An estimation method according to an eighth aspect has a voltage measurement step, a current measurement step, a voltage estimation step, and a notification step. The voltage measurement step is a step of measuring the voltage (V1) applied to the cable (C1) connected between the power converter (1) and the moving body (3). A power converter (1) is provided between a storage battery (31) of a mobile body (3) and an electric power system (4) and connected to a storage battery (CN1) via a connector (CN1) connected to the mobile body (3). 31) can be regulated. The current measurement step is a step of measuring the current flowing through the cable (C1). The voltage estimation step is a step of estimating the connector voltage (V0) applied to the connector (CN1) based on the measurement results of the voltage measurement step and the current measurement step. The notification step is a step of notifying the mobile object (3) of the connector voltage (V0) estimated in the voltage estimation step.

This aspect has the advantage of improving the estimation accuracy of the connector voltage (V0) applied to the connector (CN1).

A program according to a ninth aspect causes one or more processors to execute the estimation method according to the eighth aspect.

This aspect has the advantage of improving the estimation accuracy of the connector voltage (V0) applied to the connector (CN1).

The configurations according to the second to seventh aspects are not essential configurations for the power conversion system (100), and can be omitted as appropriate.

100 power conversion system 1 power converter 124 voltage measurement unit 125 current measurement unit 126 voltage estimation unit 127 notification unit 128 input unit 129 cable voltage measurement unit 2 cable supporter 20 connection unit 3 moving object 31 storage battery 4 power system C1 cable C11 th 1 cable C12 2nd cable CN1 connector I1 current V0 connector voltage V1, V2 voltage

Claims (9)

A power conversion system comprising: a power converter provided between a storage battery of a mobile body and an electric power system, and capable of adjusting DC power charged in the storage battery via a connector connected to the mobile body. Te ,
The power converter is
a voltage measuring unit that measures a voltage applied to a cable connected between the moving body and the power converter;
and a current measuring unit that measures the current flowing through the cable,
The power conversion system is
a voltage estimating unit for estimating a connector voltage applied to the connector based on measurement results of each of the voltage measuring unit and the current measuring unit;
a notification unit that notifies the moving object of the connector voltage estimated by the voltage estimation unit;
power conversion system. further comprising a cable support for supporting the cable;
The cable supporter is connected between a first cable among the cables that is connected between the moving body and the cable supporter, and between the cable supporter and the power converter among the cables. having a connecting portion to which the second cable is connected;
The power conversion system according to claim 1. further comprising an input unit capable of inputting information about at least the second cable,
The voltage estimation unit estimates the connector voltage using the information input to the input unit.
The power conversion system according to claim 2. The cable support has a cable voltage measurement unit that measures the voltage applied to the first cable,
The voltage estimation unit estimates the connector voltage using the measurement result of the cable voltage measurement unit.
The power conversion system according to claim 2. The voltage estimator is provided in the power converter,
The power conversion system according to any one of claims 1-4. Used in the power conversion system according to any one of claims 1 to 5,
is provided between the storage battery and the power system, and can adjust the DC power charged to the storage battery through the connector,
the voltage measurement unit;
the current measurement unit;
comprising
power converter. Used in the power conversion system according to any one of claims 1 to 5,
supporting the cable;
comprising the voltage estimator,
cable support. Between a power converter provided between a storage battery of a mobile body and an electric power system and capable of adjusting DC power charged in the storage battery via a connector connected to the mobile body, and the mobile body a voltage measurement step of measuring the voltage applied to the connected cable;
a current measuring step of measuring the current flowing through the cable; a voltage estimating step of estimating a connector voltage applied to the connector based on the measurement results of each of the voltage measuring step and the current measuring step;
a notification step of notifying the moving body of the connector voltage estimated in the voltage estimation step;
estimation method. to one or more processors;
causing the estimation method according to claim 8 to be executed;
program.

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