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US-12626967-B2 - Temperature raising device

US12626967B2US 12626967 B2US12626967 B2US 12626967B2US-12626967-B2

Abstract

A temperature raising device includes a parallel circuit including a capacitor connected in parallel to a battery that is a temperature raising target, and an alternating current (AC) generation circuit connected to the parallel circuit. When capacitance of the capacitor is denoted by C P , an inductance component of the battery is denoted by L S , and a resistance component of the battery is denoted by R S , C P satisfies Inequality (1) and an angular frequency ω of the AC generation circuit satisfies Eq. (2). C P < 2 ⁢ L S R S 2 ( 1 ) ω = 2 ⁢ L S - C P ⁢ R S 2 2 ⁢ C P ⁢ L S 2 ( 2 )

Inventors

  • Yasumichi Onuki

Assignees

  • HONDA MOTOR CO., LTD.

Dates

Publication Date
20260512
Application Date
20230217
Priority Date
20220222

Claims (19)

  1. 1 . A temperature raising device comprising: a parallel circuit including a capacitor connected in parallel to a battery that is a temperature raising target; and an alternating current (AC) generation circuit connected to the parallel circuit, wherein, when capacitance of the capacitor is denoted by C P , an inductance component of the battery is denoted by L S , and a resistance component of the battery is denoted by R S , C P satisfies Inequality (1) and an angular frequency ω of the AC generation circuit satisfies Eq. (2) C P < 2 ⁢ L S R S 2 ( 1 ) ω = 2 ⁢ L S - C P ⁢ R s 2 2 ⁢ C P ⁢ L S 2 . ( 2 )
  2. 2 . The temperature raising device according to claim 1 , wherein the AC generation circuit includes a generation circuit configured to generate a ripple current, and wherein the ripple current generated by the generation circuit flows through the parallel circuit.
  3. 3 . The temperature raising device according to claim 2 , wherein the generation circuit includes: a first rectification element; a first switching element connected in parallel to the first rectification element; a second rectification element connected in series with the first rectification element; and a second switching element connected in parallel to the second rectification element.
  4. 4 . The temperature raising device according to claim 3 , further comprising an amplitude adjustment circuit configured to adjust an amplitude of the ripple current.
  5. 5 . The temperature raising device according to claim 4 , wherein the amplitude adjustment circuit adjusts the amplitude of the ripple current by changing a duty ratio between the first switching element and the second switching element.
  6. 6 . The temperature raising device according to claim 1 , wherein the battery includes a first battery; and a second battery connected in series with the first battery, wherein the capacitor includes a first capacitor connected in parallel to the first battery; and a second capacitor connected in parallel to the second battery, wherein the AC generation circuit includes a first generation circuit connected to a first parallel circuit including the first battery and the first capacitor and configured to generate a first ripple current; and a second generation circuit connected to a second parallel circuit including the second battery and the second capacitor and configured to generate a second ripple current, and wherein the temperature raising device further comprises a phase adjustment circuit configured to provide a phase difference between the first ripple current and the second ripple current.
  7. 7 . The temperature raising device according to claim 1 , further comprising: a first current limiting element connected between the battery and the capacitor; and a second current limiting element connected between the capacitor and the AC generation circuit and having a rated capacity different from that of the first current limiting element.
  8. 8 . The temperature raising device according to claim 1 , further comprising a current cutoff element connected between the battery and the capacitor.
  9. 9 . The temperature raising device according to claim 1 , wherein a ratio of an electric current of the inductance component to an electric current input to the parallel circuit by the AC generation circuit exceeds 1.
  10. 10 . A temperature raising device comprising: a parallel circuit including a capacitor connected in parallel to a battery that is a temperature raising target; and an AC generation circuit connected to the parallel circuit, wherein, when capacitance of the capacitor is denoted by C P , an inductance component of the battery is denoted by L S , and a resistance component of the battery is denoted by R S , C P satisfies Inequality (1) and an angular frequency ω of the AC generation circuit satisfies Inequality (47) C P < 2 ⁢ L S R S 2 ( 1 ) ω < 2 ⁢ L S - C P ⁢ R S 2 C P ⁢ L S 2 ( 47 )
  11. 11 . The temperature raising device according to claim 10 , wherein the AC generation circuit includes a generation circuit configured to generate a ripple current, wherein the ripple current generated by the generation circuit flows through the parallel circuit, wherein the temperature raising device further comprises an amplitude adjustment circuit configured to adjust an amplitude of the ripple current, and wherein the amplitude adjustment circuit adjusts the amplitude of the ripple current by changing a frequency of the ripple current.
  12. 12 . The temperature raising device according to claim 10 , wherein the AC generation circuit includes a generation circuit configured to generate a ripple current, and wherein the ripple current generated by the generation circuit flows through the parallel circuit.
  13. 13 . The temperature raising device according to claim 12 , wherein the generation circuit includes: a first rectification element; a first switching element connected in parallel to the first rectification element; a second rectification element connected in series with the first rectification element; and a second switching element connected in parallel to the second rectification element.
  14. 14 . The temperature raising device according to claim 13 , further comprising an amplitude adjustment circuit configured to adjust an amplitude of the ripple current.
  15. 15 . The temperature raising device according to claim 14 , wherein the amplitude adjustment circuit adjusts the amplitude of the ripple current by changing a duty ratio between the first switching element and the second switching element.
  16. 16 . The temperature raising device according to claim 12 , further comprising a current cutoff element connected between the battery and the capacitor.
  17. 17 . The temperature raising device according to claim 10 , wherein the battery includes a first battery; and a second battery connected in series with the first battery, wherein the capacitor includes a first capacitor connected in parallel to the first battery; and a second capacitor connected in parallel to the second battery, wherein the AC generation circuit includes a first generation circuit connected to a first parallel circuit including the first battery and the first capacitor and configured to generate a first ripple current; and a second generation circuit connected to a second parallel circuit including the second battery and the second capacitor and configured to generate a second ripple current, and wherein the temperature raising device further comprises a phase adjustment circuit configured to provide a phase difference between the first ripple current and the second ripple current.
  18. 18 . The temperature raising device according to claim 10 , further comprising: a first current limiting element connected between the battery and the capacitor; and a second current limiting element connected between the capacitor and the AC generation circuit and having a rated capacity different from that of the first current limiting element.
  19. 19 . The temperature raising device according to claim 10 , wherein a ratio of an electric current of the inductance component to an electric current input to the parallel circuit by the AC generation circuit exceeds 1.

Description

CROSS-REFERENCE TO RELATED APPLICATION Priority is claimed on Japanese Patent Application No. 2022-025658, filed Feb. 22, 2022, the content of which is incorporated herein by reference. BACKGROUND Field of the Invention The present invention relates to a temperature raising device. Description of Related Art From the viewpoint of reducing automobile exhaust gas and/or CO2 emissions, interest in electric vehicles is increasing and the use of lithium-ion secondary batteries is being considered for in-vehicle applications. Because a secondary battery such as a lithium-ion secondary battery has high performance in a specific temperature range, a device for raising the temperature may be attached. For example, there is technology for raising the temperature by connecting a coil, a capacitor, and an alternating current (AC) generation circuit in series with a secondary battery and causing an AC current to flow through the secondary battery (Japanese Patent No. 4081855). Also, capacitors are generally provided in an input portion of an inverter and an input/output portion of a converter. When a resonant current is intentionally generated for raising the temperature of the secondary battery, it is desirable to arrange the secondary battery in the vicinity of the capacitor. Meanwhile, resonant currents may occur unintentionally and accidentally. For example, if a frequency of the resonant current is close to an operating frequency of a power control unit (PCU) such as an inverter, resonance occurs in a normal operation. A reactor may be provided so that the resonant current due to such a capacitor and an inductance component is suppressed (Japanese Unexamined Patent Application, First Publication No. 2004-166358). SUMMARY As in Japanese Unexamined Patent Application, First Publication No. 2004-166358, in a measure to establish a difference between the resonance frequency and the operating frequency by adding the reactor to increase the inductance or increase the capacitance of the input capacitor, because the resonance frequency is lowered and the magnification of the current flowing through the secondary battery with respect to the input current is lowered, there is room for improvement in energy efficiency. Accordingly, in the related art, an unintended resonant current may be generated or the temperature rise efficiency may not be sufficient. The present invention has been made in consideration of such circumstances, and an objective of the present invention is to provide a temperature raising device capable of raising a temperature of a secondary battery more efficiently while suppressing the generation of an unintended resonant current. A temperature raising device according to the present invention adopts the following configurations. (1): According to an aspect of the present invention, there is provided a temperature raising device including: a parallel circuit including a capacitor connected in parallel to a battery that is a temperature raising target; and an alternating current (AC) generation circuit connected to the parallel circuit, wherein, when capacitance of the capacitor is denoted by CP, an inductance component of the battery is denoted by LS, and a resistance component of the battery is denoted by RS, CP satisfies Inequality (1) and an angular frequency ω of the AC generation circuit satisfies Eq. (2). CP<2⁢LSRS2(1)ω=2⁢LS-CP⁢RS22⁢CP⁢LS2(2)(2): According to another aspect of the present invention, there is provided a temperature raising device including: a parallel circuit including a capacitor connected in parallel to a battery that is a temperature raising target; and an AC generation circuit connected to the parallel circuit, wherein, when capacitance of the capacitor is denoted by CP, an inductance component of the battery is denoted by LS, and a resistance component of the battery is denoted by RS, CP satisfies Inequality (1) and an angular frequency ω of the AC generation circuit satisfies Inequality (47). CP<2⁢LSRS2(1)ω<2⁢LS-CP⁢RS2CP⁢LS2(47)(3): In the above-described aspect (1) or (2), the AC generation circuit includes a generation circuit configured to generate a ripple current, and the ripple current generated by the generation circuit flows through the parallel circuit.(4): In the above-described aspect (3), the generation circuit includes: a first rectification element; a first switching element connected in parallel to the first rectification element; a second rectification element connected in series with the first rectification element; and a second switching element connected in parallel to the second rectification element.(5): In the above-described aspect (4), the temperature raising device further includes an amplitude adjustment circuit configured to adjust an amplitude of the ripple current.(6): In the above-described aspect (5), the amplitude adjustment circuit adjusts the amplitude of the ripple current by changing a duty ratio between the first switching element and the se