Method for controlling on-board charger of eco-friendly vehicle

• US 9,481,255 B2
• Filed: 12/14/2014
• Issued: 11/01/2016
• Est. Priority Date: 07/28/2014
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Yim, Jeong Bin, Jeon, Jae Hwa, Han, Dae Woong, Lee, Sang Kyu
• Primary Examiner(s): Memula, Suresh
• Application Number:
  US14/569,711
• Publication Number:
  US 20160023560A1
• Time in Patent Office: 688 Days
• Field of Search: 320/109
• US Class Current: 1/1
• CPC Class Codes: B60L 53/14 Conductive energy transfer
• CPC Class Codes: B60L 53/20 characterised by converters located in the vehicle
• CPC Class Codes: B60L 53/62 in response to charging parameters, e.g. current, voltage or electrical charge
• CPC Class Codes: B60L 53/64 Optimising energy costs, e.g. responding to electricity rates
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• 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 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y02T 90/167 Systems integrating technologies related to power network operation and communication or information technologies for supporting the interoperability of electric or hybrid vehicles, i.e. smartgrids as interface for battery charging of electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: Y04S 30/14 Details associated with the interoperability, e.g. vehicle recognition, authentication, identification or billing

Abstract

A method for controlling an on-board charger (OBC) of an eco-friendly vehicle can widen the range of an AC input power frequency at which the charging operation of the OBC is possible without increasing the capacity of a power factor correction (PFC) capacitor. According to the method, an increase in output voltage ripple of the PFC capacitor is suppressed by sensing an AC input voltage frequency and then performing variable control of decreasing output power of the OBC based on the sensed frequency, i.e., a variable control of decreasing the output power of the OBC as the AC input voltage frequency decreases, so that the range of the AC input power frequency at which the charging operation of the OBC is possible can be extended without increasing the capacity of a PFC power element.

Claims

1. A method for controlling an on-board charger (OBC) of an eco-friendly vehicle, the method comprising the steps of:

detecting a current AC input power frequency (f) input to a power factor correction (PFC) converter of the OBC;

comparing magnitudes between the current AC input power frequency (f) and a first low frequency (f_min1) that is a frequency at a time when the maximum value of an output voltage ripple of a PFC capacitor does not exceed a PFC output over-voltage protection specification;

comparing magnitudes between the current AC input power frequency (f) and a second low frequency (f_min2) that is a limit reference frequency of variable control of decreasing an output power (P_out) of the OBC, when the current AC input power frequency (f) is less than the first low frequency (f_min1); and

performing power derating control of decreasing the output power P_out of the OBC, when the current AC input power frequency (f) is less than the first low frequency (f_min1), and simultaneously greater than the second low frequency (f_min2).

2. The method of claim 1, wherein the power derating control of decreasing the output power of the OBC is performed until the output voltage ripple of the PFC capacitor does not exceed the PFC output over-voltage protection specification.

3. The method of claim 1, wherein, when the current AC input power frequency (f) is greater than the first low frequency (f_min1), control of maintaining output power for charging of the OBC is performed.

4. The method of claim 1, wherein, when the current AC input power frequency (f) is changed to less than the second low frequency (f_min2), control of stopping the charging operation of the OBC is performed.

5. A non-transitory computer readable medium containing program instructions executed by a controller, the computer readable medium comprising:

program instructions that detect a current AC input power frequency input to a power factor correction (PFC) converter of an on-board charger (OBC) of an eco-friendly vehicle;

program instructions that compare magnitudes between the current AC input power frequency (f) and a first low frequency (f_min1) that is a frequency at a time when the maximum value of an output voltage ripple of a PFC capacitor does not exceed a PFC output over-voltage protection specification;

program instructions that compare magnitudes between the current AC input power frequency (f) and a second low frequency (f_min2) that is a limit reference frequency of variable control of decreasing an output power (P_out) of the OBC, when the current AC input power frequency (f) is less than the first low frequency (f_min1); and

program instructions that perform power derating control of decreasing the output power P_out of the OBC, when the current AC input power frequency (f) is less than the first low frequency (f_min1), and simultaneously greater than the second low frequency (f_min2).