Heat-pump performance: voltage dip/sag, under-voltage and over-voltage

Abstract

Reverse cycle air-source heat-pumps are an increasingly significant load in New Zealand and in many other countries. This has raised concern over the impact wide-spread use of heat-pumps may have on the grid. The characteristics of the loads connected to the power system are changing because of heat-pumps. Their performance during under-voltage events such as voltage dips has the potential to compound the event and possibly cause voltage collapse. In this study, results from testing six heat-pumps are presented to assess their performance at various voltages and hence their impact on voltage stability.

Keywords

• heat pumps
• power system dynamic stability
• power grids
• reverse cycle air-source heat-pumps
• New Zealand
• power system
• under-voltage events
• voltage dips
• voltage collapse
• voltage stability