Charging system using wound rotor synchronous motor

• US 10,243,388 B2
• Filed: 12/16/2016
• Issued: 03/26/2019
• Est. Priority Date: 10/26/2016
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group), Kia Motors Corporation (Kia Corp.), Seoul National University R&DB Foundation (Seoul National University)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group), Kia Motors Corporation (Kia Corp.), Seoul National University R&DB Foundation (Seoul National University)
• Inventors: Shin, Ho Joon, Kwak, Mu Shin, Lee, Young Kook, Kim, Sung Kyu, Ha, Jung Ik, Han, Yong Su
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): Willoughby, Terrence
• Application Number:
  US15/382,262
• Publication Number:
  US 20180115180A1
• Time in Patent Office: 830 Days
• CPC Class Codes: B60L 53/24 Using the vehicle's propulsion converter for charging
• CPC Class Codes: H02J 3/18 Arrangements for adjusting, eliminating or compensating reactive power in networks for adjustment of voltage H02J3/16
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: H02J 7/24 using discharge tubes or semiconductor devices
• CPC Class Codes: H02K 1/14 Stator cores with salient poles
• CPC Class Codes: H02K 1/24 Rotor cores with salient poles ; Variable reluctance rotors
• CPC Class Codes: H02K 19/12 characterised by the arrangement of exciting windings, e.g. for self-excitation, compounding or pole-changing
• CPC Class Codes: H02P 2101/45 for motor vehicles, e.g. car alternators
• CPC Class Codes: H02P 23/14 Estimation or adaptation of motor parameters, e.g. rotor time constant, flux, speed, current or voltage
• CPC Class Codes: H02P 27/06 using dc to ac converters or inverters H02P27/05 takes precedence
• CPC Class Codes: H02P 6/32 Arrangements for controlling wound field motors, e.g. motors with exciter coils
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• 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

Disclosed herein is a charging system using a wound rotor synchronous motor, capable of increasing a battery charging capacity while reducing the volume, weight, and/or cost of a vehicle increased due to an on-vehicle charging circuit. The charging system includes an inverter converting a DC output of a battery into a plurality of AC signals having different phases, a wound rotor synchronous motor having a plurality of stator coils, to which the AC signals having different phases are respectively input, and a field coil forming a mutual inductance with the stator coils, the field coil being installed in a rotor to form a magnetic flux using the DC output of the battery, and a controller allowing the battery and the field coil to be insulated from each other in a charge mode in which electricity from a grid is applied to the field coil of the wound rotor synchronous motor.

Claims

1. A charging system using a wound rotor synchronous motor, comprising:

an inverter configured to convert a direct current output of a battery into a plurality of alternating current (AC) signals having different phases;

a wound rotor synchronous motor comprising a plurality of stator coils connected to receive the AC signals having different phases respectively, and a field coil configured to form a mutual inductance with the stator coils, the field coil being installed in a rotor to form a magnetic flux using a direct current output of the battery and being connected to a grid when the battery is charged;

a charging circuit connected in parallel between a connection end of the battery and the inverter and a connection end of the field coil of the wound rotor synchronous motor and the grid; and

a controller configured to allow the battery and the field coil to be selectively insulated from each other in a charge mode in which electricity from a grid is applied to the field coil of the wound rotor synchronous motor;

wherein, in the charge mode, the controller controls charging power supplied to the battery through the field coil and the stator coils, and the controller controls charging power supplied to the battery through the charging circuit.

2. The charging system according to claim 1, wherein when the power to be supplied for charging the battery is equal to or less than the power supplied through the charging circuit in the charge mode, the controller allows the battery and the field coil to be insulated from each other so as to prevent charging power from being supplied to the battery through the field coil, and allows charging power to be supplied to the battery through the charging circuit.

3. The charging system according to claim 1, wherein when the power to be supplied for charging the battery exceeds the power supplied through the charging circuit in the charge mode, the controller allows the battery and the field coil to be insulated from each other and controls the inverter so as to transfer electricity the field coil receives from the grid to the stator coils, thereby charging the battery.

4. The charging system according to claim 1, wherein, in the charge mode, the controller allows the battery and the field coil to be insulated from each other, controls the inverter so as to transfer electricity the field coil receives from the grid to the stator coils, allows charging power to be supplied to the battery through the charging circuit, and controls charging power supplied to the battery through the field coil and the stator coils and charging power supplied to the battery through the charging circuit.

5. The charging system according to claim 1, wherein the controller is configured to allow the battery to be electrically connected to the field coil when the wound rotor synchronous motor rotates.

6. The charging system according to claim 3, wherein in the charge mode:

the controller derives a charging power command value for charging the battery with reference to a voltage of the battery;

the controller derives an input power command value based on an error between supply power actually supplied to the battery and the charging power command value;

the controller derives a sine component of an input current command value to the field coil by applying a maximum grid voltage value to the input current command value;

the controller derives a sine component of a d-axis current command value in the stator coils, based on an error between the input current command value and a sine component of a current input to the field coil, and derives a cosine component of the d-axis current command value in the stator coils, based on an error between “

0” and

a cosine component of the current input to the field coil;

the controller derives a d-axis current command value in the stator coils, based on an error between the sine and cosine components of the d-axis current command value in the stator coils and a phase angle of the grid power;

the controller derives a d-axis voltage command value and a q-axis voltage command value in the stator coils, based on the d-axis current command value and a q-axis current command value having a value of 0 in the stator coils;

the controller derives a three-phase voltage command value (V*_abcs) by converting the d-axis voltage command value and the q-axis voltage command value into a three-phase voltage; and

the controller controls an on/off duty cycle of a switching element of the inverter in order to output the three-phase voltage command value (V*_abcs).

7. The charging system according to claim 3, wherein in the charge mode:

the controller derives a charging power command value for charging the battery with reference to a voltage of the battery;

the controller derives an input power command value (P*_in) based on an error between supply power actually supplied to the battery and the power command value;

the controller calculates a sine component (I*_dss) and a cosine component (I*_dsc) of a d-axis current command value in the stator coils using the following equations,

8. The charging system according to claim 1, further comprising:

a rectifier circuit unit configured to rectify electricity from the grid; and

a switching circuit unit configured to convert an output of the rectifier circuit unit into an AC signal having a predetermined frequency and to provide the AC signal having the predetermined frequency to the field coil.

9. The charging system according to claim 1, wherein electricity from the grid is directly applied to both ends of the field coil.

10. The charging system according to claim 1, further comprising;

a power factor correction circuit unit configured to correct a power factor of electricity from the grid; and

a switching circuit unit configured to convert an output of the power factor correction circuit unit into an AC signal having a predetermined frequency and to provide the AC signal having the predetermined frequency to the field coil.

11. A charging system using a wound rotor synchronous motor, comprising:

an inverter configured to selectively operate so as to output a plurality of alternating current (AC) signals having different phases by converting a direct current output of a battery or so as to provide a direct current output to the battery by converting a plurality of AC signals input to the inverter;

a wound rotor synchronous motor comprising a plurality of stator coils connected to receive the AC signals having different phases from the inverter, and a field coil installed in a rotor so as to form a mutual inductance with the stator coils;

a switch unit configured to selectively and electrically connect the battery to the field coil or to disconnect the battery from the field coil;

a charging circuit connected in parallel between a connection end of the battery and the inverter and a connection end of the field coil of the wound rotor synchronous motor and a grid; and

a controller configured to control a connection or disconnection state of the switch unit in a charge mode in which electricity from the grid is applied to the field coil of the wound rotor synchronous motor,

wherein when the wound rotor synchronous motor is driven, the controller allows the switch unit to be in a connection state in order to drive the wound rotor synchronous motor using a magnetic flux generated in the field coil by the direct current output of the battery, and in the charge mode, the controller allows the switch unit to be in an disconnection state, and controls the charging circuit so as to supply charging power to the battery through the charging circuit or controls the inverter so as to transfer the electricity the field coil receives from the grid to the stator coils, thereby supply charging power to the battery,

wherein, in the charge mode, the controller controls charging power supplied to the battery through the field coil and the stator coils, and the controller controls charging power supplied to the battery through the charging circuit.

12. The charging system according to claim 11, wherein when the power to be supplied for charging the battery is equal to or less than the power supplied through the charging circuit in the charge mode, the controller prevents the charging power from being supplied to the battery through the field coil, and allows the charging power to be supplied to the battery through the charging circuit.

13. The charging system according to claim 11, wherein when the power to be supplied for charging the battery exceeds the power supplied through the charging circuit in the charge mode, the controller controls the inverter so as to transfer electricity the field coil receives from the grid to the stator coils, thereby charging the battery.