DC/DC converter, on-board unit and charging device

• US 9,608,526 B2
• Filed: 04/27/2012
• Issued: 03/28/2017
• Est. Priority Date: 04/27/2012
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Okura, Susumu, Ohsawa, Takashi
• Primary Examiner(s): Pham, Emily P
• Application Number:
  US14/371,682
• Publication Number:
  US 20140368167A1
• Time in Patent Office: 1,796 Days
• US Class Current: 1/1
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 53/20 characterised by converters located in the vehicle
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02M 3/33507 with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence
• CPC Class Codes: H02M 3/33576 having at least one active switching element at the secondary side of an isolation transformer
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

A DC/DC converter 1 is configured to allow separation of a primary side constitution unit 3 and a secondary side constitution unit 4 of a transformer 2. A secondary side switching element FET 2 is provided in the secondary side constitution unit 4, and controls power supply to a load 12 by intermitting an output of a secondary winding L2. The primary side constitution unit 3 detects an electrical behavior of the primary side generated by the intermittent operation of the secondary side, and controls the power supplied from the primary winding L1 to the secondary winding L2 by operating the intermittent operation of the primary side switching element FET 1 such that a cycle or duty of the intermittent operation of the secondary side falls within a predetermined range.

Claims

1. A DC/DC converter configured to allow separation of a primary side constitution unit and a secondary side constitution unit of a transformer,

the primary side constitution unit including:

a primary winding of the transformer;

a primary side switching element that intermits a current flowing from an external power source to the primary winding; and

a primary side control unit that controls power supplied to the primary winding to an arbitrary value by operating an intermittent operation of the primary side switching element, and

the secondary side constitution unit including;

a secondary winding of the transformer;

a secondary side switching element that intermits a current flowing from the secondary winding to a load connected to the secondary side constitution unit; and

a secondary side control unit that controls power supplied to the load to an arbitrary value by operating an intermittent operation of the secondary side switching element,

wherein the primary side control unit detects an electrical behavior inside the primary side constitution unit generated by the intermittent operation of the secondary side switching element, and controls power supplied from the primary winding to the secondary winding by operating the primary side switching element on the basis of this electrical behavior.

2. The DC/DC converter according to claim 1, wherein the electrical behavior is a fluctuation of a voltage generated in the primary winding, or a fluctuation of a current flowing through the primary winding.

3. The DC/DC converter according to claim 1, wherein the primary side constitution unit includes a primary side auxiliary winding magnetically coupled to the primary winding, and the electrical behavior is a fluctuation of a voltage generated in the primary side auxiliary winding, or a fluctuation of a current flowing through the primary side auxiliary winding.

4. The DC/DC converter according to claim 1, wherein the secondary side control unit, as the intermittent operation of the secondary side switching element, performs an operation changing a repetition cycle of conduction and non-conduction by making constant one of a conducting time and a non-conducting time of the secondary side switching element, and making variable the other of the conducting time and the non-conducting time of the secondary side switching element, or performs an operation changing a ratio of the conducting time and non-conducting time by making constant the repetition cycle of the conduction and non-conduction.

5. The DC/DC converter according to claim 4, wherein the primary side control unit controls the power supplied from the primary winding to the secondary winding such that the intermittent operation of the secondary side switching element has a predetermined cycle, or such that a predetermined ratio of the conducting time and non-conducting time is achieved.

6. The DC/DC converter according to claim 1, wherein the secondary side constitution unit includes a smoothing capacitor that smooths an output of the secondary side switching element.

7. The DC/DC converter according to claim 1, wherein the secondary side constitution unit includes a DC/DC converter for conversion that is operated by the secondary side switching element and converts an output of the secondary winding arbitrarily.

8. The DC/DC converter according to claim 1, wherein when the electrical behavior generated by the operation of the secondary side control unit cannot be detected for a predetermined period during the intermittent operation of the primary side switching element, the primary side control unit stops the operation of the primary side switching element.

9. The DC/DC converter according to claim 1, wherein when the electrical behavior generated by the operation of the secondary side control unit cannot be detected for a predetermined period during the intermittent operation of the primary side switching element, the primary side control unit stops the operation of the primary side switching element for a predetermined waiting time and then resumes the intermittent operation of the primary side switching element, continues this intermittent operation of the primary side switching element when the electrical behavior can be detected at the time of this resumption, and stops the operation of the primary side switching element for the predetermined waiting time again when the electrical behavior cannot be detected.

10. The DC/DC converter according to claim 1, wherein a magnetic member wound by the primary winding or the secondary winding is a substantially rod shape or a substantially rectangular parallelepiped shape.

11. The DC/DC converter according to claim 1, wherein a magnetic member wound by the primary winding or the secondary winding is a substantially disc shape or substantially cylindrical shape.

12. The DC/DC converter according to claim 1, wherein one or both of the primary side constitution unit and the secondary side constitution unit include a wiring and a capacitor for resonance to thus constitute a resonance type DC/DC converter.

13. An on-board unit comprising:

a load unit mounted on a vehicle; and

a DC/DC converter according to claim 1 that supplies power to the load unit, further comprising;

a movable part that is movable against the vehicle, wherein the primary side constitution unit of the DC/DC converter is installed in the vehicle, and the secondary side constitution unit and the load unit are installed in the movable part.

14. An on-board unit comprising:

a load unit mounted on a vehicle; and

a DC/DC converter according to claim 1 that supplies power to the load unit, further comprising;

a fixed part fixed to the vehicle; and

a movable part that is movable against the fixed part, wherein the primary side constitution unit of the DC/DC converter is installed in the fixed part, and the secondary side constitution unit and the load unit are installed in the movable part.

15. The on-board unit according to claim 13, wherein the load unit is a semiconductor light source, and the DC/DC converter is a lighting device that supplies power to light this semiconductor light source.

16. The on-board unit according to claim 14, wherein the load unit is a semiconductor light source, and the DC/DC converter is a lighting device that supplies power to light this semiconductor light source.

17. A charging device comprising a DC/DC converter according to claim 1 that supplies charging power to a battery mounted on a vehicle, wherein the primary side constitution unit of the DC/DC converter is installed outside the vehicle, while the secondary side constitution unit is installed in the vehicle.