Multi-module, scalable, high power density, radiation-hardened power converter interface system

• US 9,419,448 B1
• Filed: 06/18/2014
• Issued: 08/16/2016
• Est. Priority Date: 06/18/2013
• Status: Active Grant

• Current Assignee: Wolfspeed, Inc.
• Original Assignee: Cree Fayetteville, Inc. (Wolfspeed, Inc.)
• Inventors: Cilio, Washington, Cilio, Edgar
• Primary Examiner(s): Kik, Phallaka
• Application Number:
  US14/308,308
• Time in Patent Office: 790 Days
• Field of Search: 320/116, 320/119, 320/121, 320/122, 320/125, 320/138, 320/160, 320/124
• US Class Current: 1/1
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: H02M 3/33546 with automatic control of the output voltage or current H02M3/33561 takes precedence
• CPC Class Codes: H02M 3/33561 having more than one ouput with independent control

Abstract

The novel cell balancing approach being disclosed minimizes the number of controlled active devices to enable Li-ion cell balancing in a battery arrangement. This is accomplished through a network of passive components associated with each cell. The network of passive components forms a bandpass filter. This allows selective charging of a cell purely based on the frequency components of a variable switching frequency controller.

Claims

1. A selective cell charger apparatus for a battery stack comprising a plurality of individual cells stacked in series, the apparatus comprising:

a plurality of unique frequency impedance networks with each unique frequency impedance network individually attached to one cell of the individual cells, the unique frequency impedance network defining a unique band pass filter frequency that is unique to one cell of the individual cells; and

a frequency shifting block generating a frequency charge signal including at least one charging frequency matching the band pass filter frequency that is unique to the one cell.

2. The apparatus of claim 1, each unique frequency impedance network including a take off component.

3. The apparatus of claim 1, each unique frequency impedance network including a series stack component.

4. A selective cell charger apparatus for a battery stack comprising a first cell and a second cell stacked in series, the apparatus comprising:

a first plurality of unique frequency impedance networks electrically connected to the first cell and defining a first band pass filter frequency;

a second plurality of unique frequency impedance networks electrically connected to the second cell and defining a second band pass filter frequency; and

a frequency shifting block generating a frequency charge signal selectively including a charge signal selected from the frequency group including a first charging frequency matching the first band pass filter frequency and a second charging frequency matching the second band pass filter frequency.

5. The apparatus of claim 4, wherein the first band pass filter frequency is forty two kilohertz.

6. The apparatus of claim 5, wherein the second band pass filter frequency is three hundred and thirty five kilohertz.

7. The apparatus of claim 4, wherein the second band pass filter frequency is three hundred and thirty five kilohertz.