# Method of detecting system function by measuring frequency response

## Abstract

Real-time battery impedance spectrum is acquired using a one-time record. Fast Summation Transformation (FST) is a parallel method of acquiring a real-time battery impedance spectrum using a one-time record that enables battery diagnostics. An excitation current to a battery is a sum of equal amplitude sine waves of frequencies that are octave harmonics spread over a range of interest. A sample frequency is also octave and harmonically related to all frequencies in the sum. The time profile of this signal has a duration that is a few periods of the lowest frequency. The voltage response of the battery, average deleted, is the impedance of the battery in the time domain. Since the excitation frequencies are known and octave and harmonically related, a simple algorithm, FST, processes the time record by rectifying relative to the sine and cosine of each frequency. Another algorithm yields real and imaginary components for each frequency.

- Inventors:

- Butte, MT
- Manchester, CT
- Idaho Falls, ID

- Publication Date:

- Research Org.:
- Idaho National Lab. (INL), Idaho Falls, ID (United States)

- Sponsoring Org.:
- USDOE

- OSTI Identifier:
- 1041020

- Patent Number(s):
- 8,150,643

- Application Number:
- 12/217,013

- Assignee:
- Battelle Energy Alliance, LLC (Idaho Falls, ID); Montana Tech of the University of Montana (Butte, MT); Qualtech Systems, Inc. (East Hartford, CT) INL

- DOE Contract Number:
- AC07-05ID14517

- Resource Type:
- Patent

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 25 ENERGY STORAGE

### Citation Formats

```
Morrison, John L, Morrison, William H, and Christophersen, Jon P.
```*Method of detecting system function by measuring frequency response*. United States: N. p., 2012.
Web.

```
Morrison, John L, Morrison, William H, & Christophersen, Jon P.
```*Method of detecting system function by measuring frequency response*. United States.

```
Morrison, John L, Morrison, William H, and Christophersen, Jon P. Tue .
"Method of detecting system function by measuring frequency response". United States. https://www.osti.gov/servlets/purl/1041020.
```

```
@article{osti_1041020,
```

title = {Method of detecting system function by measuring frequency response},

author = {Morrison, John L and Morrison, William H and Christophersen, Jon P},

abstractNote = {Real-time battery impedance spectrum is acquired using a one-time record. Fast Summation Transformation (FST) is a parallel method of acquiring a real-time battery impedance spectrum using a one-time record that enables battery diagnostics. An excitation current to a battery is a sum of equal amplitude sine waves of frequencies that are octave harmonics spread over a range of interest. A sample frequency is also octave and harmonically related to all frequencies in the sum. The time profile of this signal has a duration that is a few periods of the lowest frequency. The voltage response of the battery, average deleted, is the impedance of the battery in the time domain. Since the excitation frequencies are known and octave and harmonically related, a simple algorithm, FST, processes the time record by rectifying relative to the sine and cosine of each frequency. Another algorithm yields real and imaginary components for each frequency.},

doi = {},

journal = {},

number = ,

volume = ,

place = {United States},

year = {2012},

month = {4}

}