Method for controlling voltage of DC link for electric vehicle

• US 20070296357A1
• Filed: 12/13/2005
• Published: 12/27/2007
• Est. Priority Date: 11/17/2005
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group), Pohang University of Science and Technology (Posco Holdings Incorporated)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group), Pohang University of Science and Technology (Posco Holdings Incorporated)
• Inventors: Kim, Sung, Song, Hong, Oh, Doo, Nam, Kwang
• Granted Patent: US 7,528,566 B2
• Time in Patent Office: Days
• US Class Current: 318/139
• CPC Class Codes: H02P 23/07 Polyphase or monophase asynchronous induction motors

Abstract

Disclosed is a method for controlling a voltage of a DC link for an electric vehicle, which can reduce a capacitance of the DC link interposed between an inverter and a DC/DC converter. The method for controlling the voltage of the DC link in a power system of a vehicle including a battery, a DC/DC converter, the DC link, an inverter, a motor, and a control part controlling the DC/DC converter and the inverter includes the steps of installing a compensator in a control loop of the control part such that a DC link current of the DC/DC converter follows a DC link current of the inverter, calculating a predetermined compensation term based on information of the motor inputted into the compensator, and applying the compensation term to a voltage node in the control loop of the control part in the compensator.

Claims

1. A method for controlling a voltage of a DC link in a power system of a vehicle including a battery, a DC/DC converter, the DC link, an inverter, a motor, and a control part controlling the DC/DC converter and the inverter, the method comprising the steps of;

installing a compensator in a control loop of the control part such that a DC link current of the DC/DC converter follows a DC link current of the inverter;

calculating a predetermined compensation term based on information of the motor inputted into the compensator; and

applying the compensation term to a voltage node in the control loop of the control part in the compensator.

2. The method as claimed in claim 1, wherein the information about the motor includes a current, a voltage, and a speed of the motor.

3. The method as claimed in claim 1, wherein the compensation term is determined through an equation,

4. The method as claimed in claim 3, wherein the average i_inv of the inverter current is obtained through a voltage equation, a phase current equation, and a phase voltage equation of the motor.

5. The method as claimed in claim 3, wherein, when the motor is a permanent magnetic synchronization motor, the equation,

6. The method as claimed in claim 3, wherein the compensation term