JP2019138844A - Internal impedance detection device and vehicle - Google Patents

Abstract

To provide an internal impedance detection device of a secondary battery in a simple device configuration that can also be applied to a power control unit not equipped with a boost converter.SOLUTION: An internal impedance detection device for detecting internal impedance of a secondary battery for outputting DC power to a power control unit at least equipped with an inverter for converting DC power to AC power and outputting it to a running motor of a vehicle includes: a component extraction part for capturing a battery voltage and a battery current of the secondary battery, extracting an AC voltage component from the battery voltage, extracting an AC current component from the battery current, and extracting a fundamental frequency component from the battery voltage or the battery current; and an impedance calculation part for calculating internal impedance of the secondary battery on the basis of the AC voltage component, AC current component, and fundamental frequency component extracted by the component extraction part.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an internal impedance detection device and a vehicle.

  In Patent Document 1 below, the frequency characteristics of the impedance of each battery block are obtained by using the carrier frequency for turning on / off the switching element in the boost converter inside the power control unit, and each battery is based on the frequency characteristics. An internal resistance detection device for a secondary battery for calculating an internal resistance value of a block is disclosed. This internal resistance detection device has conventionally been considered in view of the problem that the internal resistance detection device becomes large and expensive because an oscillator is required by generating an AC signal having a plurality of frequencies in order to acquire the frequency characteristics. An object of the present invention is to detect the internal resistance value of the secondary battery with a simple device configuration by using the carrier frequency of the boost converter.

JP 2008-175556 A

  By the way, the power control unit in the above background art is a power device generally called a power control unit, and in a hybrid vehicle or an electric vehicle, a plurality of powers for converting the output of a secondary battery such as a lithium ion battery into AC power. It is a collection of conversion circuits. Such power control units may be provided with a boost converter or may not be provided with a boost converter depending on vehicle specifications. Therefore, the application destination of the background art is limited to a power control unit (power converter) including a boost converter.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a secondary battery internal impedance detection device having a simple device configuration that can be applied to a power control unit that does not include a boost converter. To do.

  In order to achieve the above object, according to the present invention, as a first solving means related to the internal impedance detection device, a power control unit including at least an inverter that converts DC power into AC power and outputs the AC power to a traveling motor of the vehicle. An internal impedance detection device for detecting an internal impedance of a secondary battery that outputs the DC power between, taking in a battery voltage of the secondary battery and a battery current flowing through the secondary battery, and alternating current from the battery voltage Extracting a voltage component, extracting an alternating current component from the battery current, and extracting a fundamental frequency component from the battery voltage or the battery current; and the alternating voltage component extracted by the component extraction portion, An impedance unit for calculating an internal impedance of the secondary battery based on an alternating current component and the fundamental frequency component And a computing unit, to employ a means of.

  In the present invention, as a second solving means relating to the internal impedance detecting device, in the first solving means, the component extraction unit is operated by high-voltage power supplied from a high-voltage power supply system, and the direct current is derived from the battery voltage. A DC cutoff circuit that extracts the AC voltage component by removing the voltage component and removes the DC current component from the battery current to extract the AC current component; and the DC cutoff circuit that is operated by the high-voltage system power, The fundamental frequency component is extracted based on the alternating voltage component and the alternating current component input from the converter, and the alternating voltage component, the alternating current component, and the fundamental frequency component are converted into a signal of a predetermined communication format and output. A high-voltage communication unit, and the impedance calculation unit is connected to the high-voltage communication unit so as to be freely communicable in a state of being insulated from a power source. And a low-voltage system calculation unit that operates with low-voltage system power and calculates the internal impedance of the secondary battery based on the AC voltage component, the AC current component, and the fundamental frequency component received from the high-voltage system communication unit. Adopt the means.

  In the present invention, as a third solving means related to the internal impedance detection device, the DC power is output to and from a power control unit that includes at least an inverter that converts DC power into AC power and outputs the AC power to a traveling motor of the vehicle. An internal impedance detection device for detecting an internal impedance of a secondary battery, taking in a battery voltage of the secondary battery, a battery current flowing through the secondary battery, and a vehicle speed detection signal indicating a vehicle speed of the vehicle, from the battery voltage An AC voltage component is extracted, an AC current component is extracted from the battery current, and a fundamental frequency component is extracted from the vehicle speed detection signal, and the AC voltage component and the AC current extracted by the component extraction unit Impedance calculation unit for calculating the internal impedance of the secondary battery based on the component and the fundamental frequency component It comprises, employing a means of.

  In the present invention, as a fourth solving means relating to the internal impedance detection device, in the third solving means, the component extraction unit is configured to add the inverter to the vehicle speed detection signal or instead of the vehicle speed detection signal. The PWM signal input as a control signal is taken in, and the fundamental frequency component is extracted based on the vehicle speed detection signal and / or the PWM signal.

  In the present invention, as a fifth solving means related to the internal impedance detection device, in the third or fourth solving means, the component extraction unit is operated by high-voltage power supplied from a high-voltage power system, and the battery The AC voltage component is extracted by removing the DC voltage component from the voltage and the DC current circuit is extracted from the battery current by removing the DC current component, and the high voltage system power is operated. A high-voltage communication unit that extracts the AC voltage component and the AC current component input from a DC cutoff circuit, converts the AC voltage component and the AC current component into a signal of a predetermined communication format, and outputs the signal; The high-voltage communication unit is communicatively connected to the high-voltage system communication unit and is operated by low-voltage system power. A low voltage system calculation unit that receives the alternating current component and extracts a fundamental frequency component from the vehicle speed detection signal or / and the PWM signal, and the impedance calculation unit is a partial function of the low voltage system calculation unit The means of being provided as is adopted.

  In the present invention, as a sixth solving means relating to the internal impedance detection device, there is provided a traveling inverter that converts the first direct current power into alternating current power and outputs the alternating current power, and a generator driven by the engine. An internal impedance of a secondary battery that inputs and outputs the first DC power and the second DC power is detected with a power control unit that includes at least an inverter for power generation that converts an output into second DC power. An internal impedance detection device that captures an engine rotation detection signal indicating the battery voltage of the secondary battery, the battery current flowing through the secondary battery and the rotation of the engine, and extracts an AC voltage component from the battery voltage; A component extractor for extracting an alternating current component from the battery current and extracting a fundamental frequency component from the engine rotation detection signal; The AC voltage component ingredients extractor has extracted, the alternating current component and on the basis of the fundamental frequency component and a impedance calculator for calculating the internal impedance of the secondary battery, employing the means of.

  In the present invention, as a seventh solving means relating to the internal impedance detection device, in the sixth solving means, the component extraction unit is added to the engine rotation detection signal or instead of the engine rotation detection signal. A means is adopted in which a PWM signal applied to the inverter is taken and the fundamental frequency component is extracted based on the engine rotation detection signal and / or the PWM signal.

  In the present invention, as an eighth solving means related to the internal impedance detection device, in the sixth or seventh solving means, the component extraction unit is operated by high-voltage power supplied from a high-voltage power system, and the battery The AC voltage component is extracted by removing the DC voltage component from the voltage and the DC current circuit is extracted from the battery current by removing the DC current component, and the high voltage system power is operated. A high-voltage communication unit that extracts the AC voltage component and the AC current component input from a DC cutoff circuit, converts the AC voltage component and the AC current component into a signal of a predetermined communication format, and outputs the signal; The high-voltage communication unit is communicatively connected to the high-voltage system communication unit and is operated by low-voltage system power. A low-voltage system arithmetic unit that receives the alternating current component and extracts a fundamental frequency component from the engine rotation detection signal or / and the PWM signal, and the impedance arithmetic unit is a part of the low-voltage system arithmetic unit A means of being provided as a function is adopted.

  In the present invention, as the first solution means for the vehicle, the internal impedance detection device according to the first or second solution means, the secondary battery, the power control unit, and the battery current are detected. A current detector is employed.

  In the present invention, as the second solution means for the vehicle, the internal impedance detection device according to any of the third to fifth solution means, the secondary battery, the power control unit, and the battery A means is provided that includes a current detector that detects a current and a rotation detection means that outputs the vehicle speed detection signal and / or the PWM signal.

  Further, in the present invention, as a third solving means relating to the vehicle, the internal impedance detection device according to any of the sixth to eighth solving means, the secondary battery, the power control unit, and the power generation And an engine, a current detector for detecting the battery current, and a rotation detection means for outputting the engine rotation detection signal and / or the PWM signal.

 According to the present invention, since the fundamental frequency component regarding the AC voltage component of the battery voltage and the AC current component of the battery current is obtained without depending on the boost converter, it can be easily applied to a power control unit that does not include the boost converter. It is possible to provide an internal impedance detection device for a secondary battery having a simple device configuration.

It is a block diagram which shows the principal impedance structure of the internal impedance detection apparatus and vehicle which concern on 1st Embodiment of this invention. It is a block diagram which shows the principal impedance structure of the internal impedance detection apparatus and vehicle which concern on 2nd Embodiment of this invention. It is a block diagram which shows the principal impedance structure of the internal impedance detection apparatus and vehicle which concern on 3rd Embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
[First Embodiment]
First, a first embodiment of the present invention will be described. The vehicle according to the first embodiment includes at least a secondary battery X, a PCU (power control unit) 1, a travel motor 2, a current detector 3, and an internal impedance detector 4 as shown in FIG. That is, this vehicle is a vehicle such as a hybrid vehicle or an electric vehicle that travels by converting the power (DC power) of the secondary battery X into AC power by the PCU 1 and driving the travel motor 2 with the AC power.

  The secondary battery X is an assembled battery such as a lithium ion battery or a fuel battery, for example, and outputs a high voltage DC power to the PCU 1 by connecting a plurality of single cells (battery cells) in series. That is, in the secondary battery X, the positive terminal P is connected to the high voltage side input terminal of the PCU1, and the negative terminal N is connected to the low voltage side input terminal of the PCU1.

  As shown in FIG. 1, such a secondary battery X is represented as an equivalent circuit including a voltage source E, a reaction resistance R1, an electric double layer capacity C, and a solution resistance R2. Among these voltage source E, reaction resistance R1, electric double layer capacity C, and solution resistance R2, reaction resistance R1, electric double layer capacity C, and solution resistance R2 are quantities indicating the internal impedance of the secondary battery X. Since the reaction resistance R1, the electric double layer capacity C, and the solution resistance R2 in the secondary battery X are well-known matters, a detailed description thereof is omitted.

  The PCU 1 is a power conversion circuit including a motor inverter that drives the traveling motor 2. The PCU 1 converts the DC power input from the secondary battery X into a three-phase AC power by switching with a plurality of switching transistors, and outputs it to the traveling motor 2. Such PCU 1 is known in several configurations, and the simplest configuration includes only the motor inverter.

  The travel motor 2 is a rotating machine that generates rotational power by three-phase AC power input from the PCU 1, and is, for example, a permanent magnet type brushless motor. The travel motor 2 rotationally drives a wheel (drive wheel) connected to the axle via a coupling machine by rotationally driving the axle. That is, the traveling motor 2 functions as a power source for traveling the vehicle.

  The current detector 3 is provided on a power line connecting the secondary battery X and the PCU 1 and detects a current (battery current) flowing between the secondary battery X and the PCU 1. The current detector 3 outputs a current detection signal indicating the battery current to the internal impedance detection device 4.

 The internal impedance detection device 4 is a device that detects the internal impedance of the secondary battery X based on the battery voltage and battery current of the secondary battery X. The internal impedance detection device 4 uses a detection method disclosed in, for example, Japanese Patent Application Laid-Open No. 2010-139423 and Japanese Patent Application Laid-Open No. 2001-351696, so that the secondary impedance is based on the battery voltage and the battery current of the secondary battery X. The internal impedance of the battery X is detected.

  Such an internal impedance detector 4 includes at least a DC cutoff circuit 4a, a high voltage CPU 4b, and a low voltage CPU 4c as shown in the figure. The DC cutoff circuit 4 a has one input terminal connected to the plus terminal P of the secondary battery X and the other input terminal connected to the current detector 3. That is, the DC cut-off circuit 4a takes in the battery voltage and battery current of the positive terminal P in the secondary battery X, extracts the AC voltage component by removing the DC voltage component from the battery voltage, and also converts the DC current from the battery current. An AC current component is extracted by removing the component.

  The DC cut-off circuit 4a outputs the DC voltage component and the AC current component to the high voltage CPU 4b. Such a DC cut-off circuit 4a operates with high-voltage power supplied from a high-voltage power supply system (not shown), and extracts the DC voltage component and the AC current component.

  The high voltage CPU 4b extracts the fundamental frequency components of the battery voltage and the battery current based on the AC voltage component and the AC current component input from the DC cutoff circuit 4a. The high voltage CPU 4b converts the AC voltage component, AC current component, and fundamental frequency component into signals of a predetermined communication format and outputs the signals to the low voltage CPU 4c. That is, the DC cutoff circuit 4a and the high voltage CPU 4b are component extraction units in the first embodiment, and the high voltage CPU 4b is a high voltage system communication unit in the first embodiment. The high voltage CPU 4b is operated by high voltage system power in the same manner as the DC cutoff circuit 4a described above.

  The low voltage CPU 4c is communicatively connected to the high voltage CPU 4b (high voltage system communication unit) while being isolated from the power source, and is a secondary battery based on the AC voltage component, AC current component, and fundamental frequency component received from the high voltage CPU 4b. It is a low-pressure system computing unit that computes the internal impedance of X. The low-voltage CPU 4c is operated by a low-voltage system power supplied from a low-voltage power system different from the above-described high-voltage power system. Such a low-voltage CPU 4c is an impedance calculation unit in the first embodiment.

  Next, the operation of the internal impedance detection device 4 and the vehicle according to the first embodiment will be described in detail.

  The vehicle according to the first embodiment travels when the PCU 1 is activated and the drive power is supplied to the travel motor 2. This PCU1 generates three-phase AC power by switching the DC power input from the secondary battery X by a plurality of internal switching transistors, but the DC power, that is, the input side of PCU1, is caused by the switching. Voltage fluctuation occurs. This voltage variation is a periodic variation whose fundamental frequency component is the switching frequency of each switching transistor, that is, the carrier frequency of a PWM (Pulse Width Modulation) signal input as a control signal to the control terminal of each switching transistor.

  The DC cut-off circuit 4a of the internal impedance detection device 4 takes in the battery voltage at the positive terminal P of the secondary battery X having such periodic fluctuations, takes in the battery current input from the current detector 3, and The AC voltage component is extracted from the battery current, and the AC current component is extracted from the battery current. The battery current input from the current detector 3 to the DC cutoff circuit 4a includes periodic fluctuations similar to the voltage fluctuations due to the same causes as the battery voltage fluctuations described above.

  The AC voltage component and the AC current component are input from the DC cutoff circuit 4a to the high voltage CPU 4b. Then, the high voltage CPU 4b extracts the battery voltage and the basic frequency component of the battery current based on the AC voltage component or / and the AC current component, and converts the AC voltage component, the AC current component, and the basic frequency component into a predetermined communication format. It converts into a signal and outputs it to low voltage CPU4c.

  When the low voltage CPU 4c receives the alternating voltage component, the alternating current component, and the fundamental frequency component from the high voltage CPU 4b, the low voltage CPU 4c calculates the internal impedance of the secondary battery X based on the alternating voltage component, the alternating current component, and the fundamental frequency component. That is, the low voltage CPU 4c is based on the AC voltage component, the AC current component, and the fundamental frequency component in the secondary battery X by using the detection method disclosed in JP 2010-139423 A or JP 2001-351696 A. Then, each value of the reaction resistance R1, the electric double layer capacity C and the solution resistance R2 of the secondary battery X is calculated.

  According to the first embodiment, the internal impedance of the secondary battery X using the AC voltage component and the AC current component generated in the battery voltage and battery current of the secondary battery X due to the operation of the PCU 1. Therefore, when supplying DC power from the secondary battery X to the PCU 1 that does not include the boost converter, it is possible to acquire the internal impedance of the secondary battery X with a simple device configuration.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. As shown in FIG. 2, the vehicle according to the second embodiment includes a secondary battery X, a PCU (power control unit) 1A, a traveling motor 2, a current detector 3, an internal impedance detector 4A, a main contactor 5A, and a sub-contactor. 5B, an axle rotation detector 6 and a FI-ECU (Fuel Injection-Electric Control Unit) 7 are provided. That is, the vehicle according to the second embodiment is a vehicle that includes an engine like a hybrid vehicle and travels using motor power generated by the travel motor 2 and engine power generated by the engine.

  In FIG. 2, the same components as those shown in FIG. 1 are denoted by the same reference numerals. In the following description, the description of the secondary battery X, the traveling motor 2, and the current detector 3 that are the same as those in the first embodiment will be omitted to avoid redundant description.

  The PCU 1A is obtained by adding the above-described PWM signal output function to the PCU 1 in the first embodiment. This PWM signal is a control signal input to the control terminal of each switching transistor constituting the PCU 1A, and is a pulse signal having a predetermined repetition frequency (carrier frequency). The PCU 1A outputs such a PWM signal to the low voltage CPU 4e of the internal impedance detection device 4A.

  The internal impedance detection device 4A includes at least a DC cutoff circuit 4a, a high voltage CPU 4d, and a low voltage CPU 4e. The high-voltage CPU 4d will be described with the DC cut-off circuit 4a omitted. The high-voltage CPU 4d converts the AC voltage component and the AC current component input from the DC cut-off circuit 4a into signals of a predetermined communication format and outputs them to the low-voltage CPU 4e. To do. That is, the high voltage CPU 4d is a high voltage communication unit in the second embodiment. Further, such a high voltage CPU 4d is operated by high voltage system power in the same manner as the DC cutoff circuit 4a described above.

  The low voltage CPU 4e is communicatively connected to the high voltage CPU 4d (high voltage system communication unit) while being insulated from the power source, and receives an AC voltage component and an AC current component from the high voltage CPU 4d. Further, the low voltage CPU 4e extracts the fundamental frequency components in the battery voltage and the battery current of the secondary battery X based on the vehicle speed detection signal input from the FI-ECU 7 and the PWM signal input from the PCU 1A, and these AC voltage components. The internal impedance of the secondary battery X is calculated based on the alternating current component and the fundamental frequency component.

  Such a low-voltage CPU 4e is operated by low-voltage power supplied from a low-voltage power supply system different from the above-described high-voltage power supply system. The DC cutoff circuit 4a and the low voltage CPU 4e are component extraction units in the second embodiment. The low-voltage CPU 4e is a low-voltage system calculation unit and an impedance calculation unit in the second embodiment. That is, in the second embodiment, the impedance calculation unit in the present invention is provided as a partial function of the low-voltage CPU 4e (low-voltage system calculation unit).

  The main contactor 5A is a switch provided between the plus terminal P of the secondary battery X and one input terminal of the PCU 1A. The sub contactor 5B is a switch provided between the negative terminal N of the secondary battery X and the other input terminal of the PCU 1A. The main contactor 5A and the sub contactor 5B are controlled to be opened and closed by a battery ECU (not shown).

  The axle rotation detector 6 is a rotation sensor that detects the number of rotations of the axle connected to the drive wheels in the vehicle. The axle rotation detector 6 outputs an axle rotation detection signal to the FI-ECU 7. The FI-ECU 7 is a control device that controls fuel injection of the engine, and generates a vehicle speed detection signal indicating the vehicle speed (traveling speed) of the vehicle based on the axle rotation detection signal input from the axle rotation detector 6. The FI-ECU 7 outputs the vehicle speed detection signal to the low pressure CPU 4e of the internal impedance detection device 4A. The FI-ECU 7 and the PCU 1A are rotation detection means in the second embodiment.

  In the internal impedance detection device 4A according to the second embodiment configured as described above, the low voltage CPU 4e extracts the fundamental frequency component in the battery voltage and battery current of the secondary battery X based on the vehicle speed detection signal and the PWM signal. The internal impedance of the secondary battery X is calculated based on the fundamental frequency component and the AC voltage component and AC current component of the secondary battery X separately received from the high voltage CPU 4d.

  That is, according to the second embodiment, it is possible to acquire the internal impedance of the secondary battery X with a simple device configuration as in the first embodiment. Further, according to the second embodiment, since the fundamental frequency component in the battery voltage and the battery current of the secondary battery X is extracted based on the vehicle speed detection signal and the PWM signal, the AC voltage component that has a relatively small amplitude variation and It is possible to extract the fundamental frequency component with higher accuracy than in the first embodiment in which the fundamental frequency component is extracted based on the alternating current component.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. As shown in FIG. 3, the vehicle according to the third embodiment includes a secondary battery X, a PCU (power control unit) 1B, a traveling motor 2, a current detector 3, an internal impedance detector 4B, a main contactor 5A, and a sub-contactor. 5B, axle rotation detector 6, FI-ECU 7A, power generation engine 8 and generator 9 are provided.

  In FIG. 3, the same components as those shown in FIG. 2 are denoted by the same reference numerals. In the following description, the description of the secondary battery X, the traveling motor 2, the current detector 3, the main contactor 5A, and the sub contactor 5B that are the same as those of the second embodiment will be omitted to avoid overlapping description.

  The PCU 1B is a power conversion circuit including at least a traveling inverter and a power generation inverter. That is, the PCU 1B converts the DC power (first DC power) input from the secondary battery X into three-phase AC power and outputs it to the traveling motor 2 and the output of the generator 9 ( An inverter for power generation is provided that converts (AC power) into DC power (second DC power) and outputs it to the secondary battery X. The traveling inverter and the power generating inverter are each composed of a plurality of switching transistors. The PCU 1B outputs a PWM signal for controlling the inverter for power generation to the low voltage CPU 4f of the internal impedance detection device 4B.

  The internal impedance detection device 4B includes at least a DC cutoff circuit 4a, a high voltage CPU 4d, and a low voltage CPU 4f. The DC cut-off circuit 4a and the high voltage CPU 4d are omitted, and the low voltage CPU 4f will be described. Receives an AC voltage component and an AC current component.

  The low-voltage CPU 4f extracts the fundamental frequency component in the battery voltage and battery current of the secondary battery X based on the engine rotation detection signal input from the FI-ECU 7A and the PWM signal input from the PCU 1B, and these AC voltages The internal impedance of the secondary battery X is calculated based on the component, the alternating current component, and the fundamental frequency component.

  The FI-ECU 7A is a control device that controls the fuel injection of the engine in the same manner as the FI-ECU 7 in the second embodiment. The FI-ECU 7A converts the engine rotation detection signal input from the power generation engine 8 to convert the internal impedance detection device 4A. Output to the low-pressure CPU 4f. This engine rotation detection signal is a frequency signal corresponding to the operation of the generator 9 driven by the generator engine 8, that is, the frequency of the AC power output from the generator 9. The FI-ECU 7A and the PCU 1B are rotation detection means in the third embodiment.

  Such a vehicle according to the third embodiment generates AC power by driving the generator 8 with the power of the power generation engine 9, and converts the AC power into second DC power by the PCU 1B. The vehicle generates charging power by charging the secondary battery X and converting the first DC power output from the secondary battery X into AC power by the PCU 1B and supplying the AC power to the traveling motor 2. That is, the secondary battery X in the third embodiment inputs and outputs (charges and discharges) the first DC power and the second DC power.

  In the internal impedance detection device 4B according to the third embodiment configured as described above, the low voltage CPU 4f extracts the fundamental frequency component in the battery voltage and battery current of the secondary battery X based on the engine rotation detection signal and the PWM signal. Then, the internal impedance of the secondary battery X is calculated based on the fundamental frequency component and the AC voltage component and AC current component of the secondary battery X separately received from the high voltage CPU 4d.

  That is, according to the third embodiment, it is possible to acquire the internal impedance of the secondary battery X with a simple device configuration as in the first and second embodiments. Further, according to the third embodiment, since the fundamental frequency component in the battery voltage and the battery current of the secondary battery X is extracted based on the engine rotation detection signal and the PWM signal, the AC voltage component that has a relatively small amplitude fluctuation In addition, it is possible to extract the fundamental frequency component more accurately than in the first embodiment in which the fundamental frequency component is extracted based on the alternating current component.

  In the second embodiment described above, since the switching frequency of the PCU 1A, that is, the carrier frequency of the PWM signal changes in accordance with the vehicle speed, it is preferable to extract the fundamental frequency component while the vehicle is traveling constantly. In the third embodiment, a PWM signal for controlling the inverter for power generation of the PCU 1B, that is, a frequency signal not directly related to the running state of the vehicle is used, so that the fundamental frequency component can be extracted with high accuracy regardless of the running state of the vehicle. Can do.

In addition, this invention is not limited to the said embodiment, For example, the following modifications can be considered.
(1) In the first embodiment, the voltage fluctuation and current fluctuation using the voltage fluctuation of the battery voltage of the secondary battery X and the current fluctuation of the battery current generated due to the operation of the PCU 1 when the vehicle is running. However, the present invention is not limited to this.
For example, when the vehicle is stopped, among the three-phase switching transistors constituting the PCU 1 (inverter), only a specific one-phase switching transistor performs a switching operation at a constant period, and the secondary battery resulting from this switching operation The fundamental frequency component may be extracted based on the voltage fluctuation of the battery voltage of X and the current fluctuation of the ionization current. According to such a method, the internal impedance of the secondary battery X can be acquired in a state where the vehicle is reliably stopped.

(2) In the second embodiment, in a vehicle that travels with the power of the engine and the power of the travel motor 2, the fundamental frequency components in the battery voltage and battery current of the secondary battery X are obtained using the vehicle speed detection signal and the PWM signal. Although extracted, this invention is not limited to this. For example, the fundamental frequency component may be extracted using one of the vehicle speed detection signal and the PWM signal.

(3) In the third embodiment, in the vehicle that generates power by the power generation engine 8 and the power generator 8 and travels by the power of the travel motor 2, the secondary battery X uses the engine rotation detection signal and the PWM signal. Although the fundamental frequency components in the battery voltage and the battery current are extracted, the present invention is not limited to this. For example, the fundamental frequency component may be extracted using one of the engine rotation detection signal and the PWM signal.

(4) In each of the above embodiments, the DC extraction circuit 4a, the high voltage CPUs 4b, 4d, and the low voltage CPUs 4c, 4e, 4f constitute the component extraction unit and the impedance calculation unit in the present invention, but the present invention is not limited to this. For example, in the first embodiment, the extraction process of the fundamental frequency component may be performed by the low voltage CPU 4c instead of the high voltage CPU 4b.

(5) Although PCU1, 1A, 1B in each said embodiment is not provided with the step-up converter, this invention is not limited to this.

X battery pack 1, 1A, 1B PCU (power control unit)
2 Traveling motor 3 Current detector 4, 4A, 4B Internal impedance detector 4a DC blocking circuit 4b, 4d High voltage CPU
4c, 4e, 4f Low pressure CPU
5A Main contactor 5B Sub contactor 6 Axle rotation detector 7, 7A FI-ECU
8 Power generation engine 9 Generator

Claims (11)

An internal impedance detection device that detects internal impedance of a secondary battery that outputs DC power between a power control unit that includes at least an inverter that converts DC power into AC power and outputs it to a traveling motor of a vehicle,
Taking in the battery voltage of the secondary battery and the battery current flowing through the secondary battery, extracting the AC voltage component from the battery voltage, extracting the AC current component from the battery current, and also the battery voltage or the battery current A component extractor for extracting a fundamental frequency component from
An internal impedance detection device comprising: an impedance calculation unit that calculates an internal impedance of the secondary battery based on the AC voltage component, the AC current component, and the fundamental frequency component extracted by the component extraction unit. The component extraction unit
It operates with high-voltage power supplied from a high-voltage power supply system, extracts the AC voltage component by removing the DC voltage component from the battery voltage, and removes the DC current component from the battery current to remove the AC current component. A DC cutoff circuit to be extracted;
The basic frequency component is extracted based on the AC voltage component and the AC current component that are operated by the high-voltage system power and input from the DC cutoff circuit, and the AC voltage component, the AC current component, and the fundamental frequency component are extracted. A high-voltage communication unit that converts the signal into a signal of a predetermined communication format and outputs the signal,
The impedance calculation unit is connected to the high-voltage system communication unit in a state of being insulated from a power source and is operated by a low-voltage system power, and receives the AC voltage component and the AC current received from the high-voltage system communication unit. The internal impedance detection device according to claim 1, further comprising a low voltage system calculation unit that calculates an internal impedance of the secondary battery based on a component and the fundamental frequency component. An internal impedance detection device that detects internal impedance of a secondary battery that outputs DC power between a power control unit that includes at least an inverter that converts DC power into AC power and outputs it to a traveling motor of a vehicle,
The battery voltage of the secondary battery, the battery current flowing through the secondary battery, and a vehicle speed detection signal indicating the vehicle speed of the vehicle are taken in, an AC voltage component is extracted from the battery voltage, and an AC current component is extracted from the battery current. A component extraction unit for extracting a fundamental frequency component from the vehicle speed detection signal;
An internal impedance detection device comprising: an impedance calculation unit that calculates an internal impedance of the secondary battery based on the AC voltage component, the AC current component, and the fundamental frequency component extracted by the component extraction unit.   The component extraction unit takes in a PWM signal input as a control signal to the inverter in addition to the vehicle speed detection signal or instead of the vehicle speed detection signal, and based on the vehicle speed detection signal and / or the PWM signal The internal impedance detection device according to claim 3, wherein the fundamental frequency component is extracted. The component extraction unit
It operates with high-voltage power supplied from a high-voltage power supply system, extracts the AC voltage component by removing the DC voltage component from the battery voltage, and removes the DC current component from the battery current to remove the AC current component. A DC cutoff circuit to be extracted;
The AC voltage component and the AC current component that are operated by the high-voltage power and input from the DC cutoff circuit are extracted, and the AC voltage component and the AC current component are converted into signals of a predetermined communication format and output. A high-pressure communication section
It is connected to the high-voltage communication unit in a state where it is insulated from the power source, and is operated by low-voltage power, receives the AC voltage component and the AC current component from the high-voltage communication unit, and receives the vehicle speed. A low-voltage operation unit that extracts a fundamental frequency component from the detection signal or / and the PWM signal,
The internal impedance detection device according to claim 3 or 4, wherein the impedance calculation unit is provided as a partial function of the low-voltage system calculation unit. At least a driving inverter that converts the first DC power into AC power and outputs it to a vehicle driving motor, and a power generation inverter that converts the output of the generator driven by the engine into second DC power An internal impedance detection device for detecting an internal impedance of a secondary battery that inputs and outputs the first DC power and the second DC power with a power control unit comprising:
The battery voltage of the secondary battery, the battery current flowing through the secondary battery, and an engine rotation detection signal indicating the rotation of the engine are taken in, an AC voltage component is extracted from the battery voltage, and an AC current component is extracted from the battery current A component extraction unit for extracting a fundamental frequency component from the engine rotation detection signal;
An internal impedance detection device comprising: an impedance calculation unit that calculates an internal impedance of the secondary battery based on the AC voltage component, the AC current component, and the fundamental frequency component extracted by the component extraction unit.   The component extraction unit captures a PWM signal input as a control signal to the inverter in addition to the engine rotation detection signal or instead of the engine rotation detection signal, and outputs the PWM signal to the engine rotation detection signal or / and the PWM signal. 7. The internal impedance detection device according to claim 6, wherein the fundamental frequency component is extracted based on the base frequency component. The component extraction unit
It operates with high-voltage power supplied from a high-voltage power supply system, extracts the AC voltage component by removing the DC voltage component from the battery voltage, and removes the DC current component from the battery current to remove the AC current component. A DC cutoff circuit to be extracted;
The AC voltage component and the AC current component that are operated by the high-voltage power and input from the DC cutoff circuit are extracted, and the AC voltage component and the AC current component are converted into signals of a predetermined communication format and output. A high-pressure communication section
It is connected to the high-voltage communication unit in a state where it is insulated from the power source and is operated by low-voltage power, receives the AC voltage component and the AC current component from the high-voltage communication unit, and the engine. A rotation detection signal or / and a low-pressure system arithmetic unit that extracts a fundamental frequency component from the PWM signal,
The internal impedance detection device according to claim 6, wherein the impedance calculation unit is provided as a partial function of the low-voltage system calculation unit. The internal impedance detection device according to claim 1 or 2,
The secondary battery;
The power control unit;
A vehicle comprising: a current detector that detects the battery current. The internal impedance detection device according to any one of claims 3 to 5,
The secondary battery;
The power control unit;
A current detector for detecting the battery current;
A vehicle comprising: a rotation detection means for outputting the vehicle speed detection signal and / or the PWM signal. The internal impedance detection device according to any one of claims 6 to 8,
The secondary battery;
The power control unit;
The generator;
The engine;
A current detector for detecting the battery current;
And a rotation detection means for outputting the engine rotation detection signal and / or the PWM signal.

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