Generator set calibration controller

• US 8,478,550 B2
• Filed: 07/23/2010
• Issued: 07/02/2013
• Est. Priority Date: 07/23/2010
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Folken, Keith Ronald, Dvorsky, Michael Allen, Meinhart, Matthew Joseph
• Primary Examiner(s): KUNDU, SUJOY K
• Application Number:
  US12/842,492
• Publication Number:
  US 20120019000A1
• Time in Patent Office: 1,075 Days
• Field of Search: 702/60, 702/62, 290/7, 324/130
• US Class Current: 702/60
• CPC Class Codes: H02P 9/00 Arrangements for controlling electric generators for the purpose of obtaining a desired output Ward-Leonard arrangements H02P7/34; vector control H02P21/00; feeding a network by two or more generators H02J; for charging batteries H02J7/14

Abstract

A calibration system for a generator set controller is disclosed. The calibration system may have a source of electric power, a controller in communication with the source and configured to monitor a parameter of the electric power and produce at least one output corresponding to the monitored parameter, and a power meter configured to measure the parameter of the electric power. The calibration system may also have a processor in communication with the source of electric power, the controller, and the power meter. The processor may be configured to direct electric power having a first test voltage from the source to the controller, and directly relate a value of the at least one output corresponding to the first test voltage and a value of the measured parameter to an offset error.

Claims

1. A method of calibrating a genset controller, comprising:

generating electric power;

monitoring the electric power at a first location;

measuring the electric power at a second location;

making a first comparison of a value of the electric power monitored at the first location with a value of the electric power measured at a second location when the electric power has desired values;

determining a monitoring offset error based on the first comparison;

calculating a first calibration factor that accounts for the monitoring offset error;

affecting future monitoring based on the first calibration factor;

generating electric power having a known low voltage level and a known high voltage level;

making a second comparison of a value of the electric power monitored at the first location with a value of the electric power measured at a second location when the electric power has the low and high voltage levels; and

determining a monitoring scale error based on the second comparison;

wherein making a first comparison and determining a monitoring offset error are done by one or more processors.

2. The method of claim 1, wherein the desired values include a zero voltage value and a zero amperage value.

3. The method of claim 1, wherein the electric power is three phase alternating current, and determining the monitoring offset error includes determining the monitoring offset error for each of the three phases of electric power.

4. The method of claim 1, further including:

calculating a second calibration factor that accounts for the monitoring scale error; and

affecting future monitoring based on the second calibration factor.

5. The method of claim 1, wherein the electric power is sinusoidal and making the second comparison includes sampling the electric power at points about midway between the known low voltage level and the known high voltage level where a slope of the electric power is greatest.

6. The method of claim 1, wherein:

the known low voltage level is about 0 volts; and

the known high voltage level is about 277 volts.

7. The method of claim 1, wherein:

the electric power is three-phase alternating current;

monitoring the electric power includes monitoring each of the three-phases; and

the method further includes;

shifting a monitoring output corresponding with two of the three phases of electric power by a known amount; and

relating a difference between the two shifted monitoring outputs and the nonshifted monitoring output to a monitoring time delay error.

8. The method of claim 7, further including:

calculating a third calibration factor that accounts for the monitoring time delay error; and

affecting future monitoring based on the third calibration factor.