Douglas Dorr

Effects of power line voltage variations on different types of 400-W high-pressure sodium ballasts

This paper presents the results of laboratory tests to determine the effects of voltage sags, interruptions and fluctuations on high-pressure sodium (HPS) lamps and ballasts. The way these ballasted lamps react to sags and interruptions in the laboratory is then compared to a model of the real-world electrical environment created from data gathered during three recent North American power quality surveys. This work also shows how HPS immunity to voltage variations depends significantly on the ballast type and the lamp age.

The neutral-to-earth voltage (NEV) test case and distribution system analysis

Modeling NEV issues requires the most detailed circuit models for distribution system analysis except for, perhaps, lightning surge protection analysis. A proposed line model benchmark is solved and results reported. Modeling NEV will become an increasingly important problem. Based on the proliferation of harmonic producing loads in residential environments, the amount of triplen harmonics will tend to increase, with an accompanying increase in neutral-earth voltages.

Studying the impact of elevated neutral to earth voltage on distribution systems due to triplen harmonics

Neutral-earth voltages have been a topic of investigation and research for many generations. Non-linear loads, and the harmonics that they generate have also been a topic of research in more recent years. An unexpected side effect of distributed nonlinear loads is an increase in neutral-earth voltages on distribution systems. A case study was presented that shows a correlation between high levels of zero sequence triplen (especially the 3rd) harmonics in distribution systems and an increase in neutral-earth voltages. A method of modeling distribution systems with distributed nonlinear loads was presented. These models were based upon circuit configurations, conductor data, grounding information, transformer data, and any previous measurement data gathered from the field. Additionally, some means for reducing neutral-earth voltages were presented

Applying HID high-pressure sodium lamps in a variable-voltage environment

This paper presents the results of laboratory tests to determine the effects of voltage sags, interruptions, and fluctuations on high-pressure sodium (HPS) lamps and ballasts. The way these ballasted lamps react to sags and interruptions in the laboratory is then compared to a model of the real-world electrical environment created from data gathered during three North American power quality surveys. This work also shows how HPS immunity to voltage variations depends significantly on the ballast type and the lamp age.

Improving process control immunity to supply voltage dips in industrial settings

In the modern industrial facility, many electrical and electronic control devices are routinely integrated into automated processes to increase both energy efficiency and productivity. In many cases these controls turn out to be very sensitive to power quality variations. In fact they can be just as sensitive to minor power system voltage dips as they are to complete power failures. The end result being that the process experiences a costly interruption in production or output. This paper focuses on the range of solutions that may be implemented to resolve common power quality related upset problems with large process applications.