Improving Accuracy of Power and Power Quality Measurements

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Improving Accuracy of Power and Power Quality Measurements (32.07 KB)

Accurate measurement of electrical power is becoming more important, as electrical power becomes a more essential and valuable commodity. It is also becoming more crucial to measure more attributes of electrical power as deregulation, and distributed generation systems result in huge increases in the number of transactions taking place where electricity is bought and sold. Buyers obviously are keen to ensure they are getting what they paid for, and distributors are keen to ensure that power supplied does not adversely affect the integrity of their network. NIST have stated that “additional low-uncertainty measurements are needed to ensure the accurate sale of power”. and “More precise measurements of standard billing parameters will be needed (e.g. energy, demand) to support contract management”[1].

At the same time, many driving forces are in place to make this measurement more difficult, and error prone. Power is becoming dirtier and more distorted, and measurements beyond straight power and energy (such as flicker) become commonplace.

The impacts of this are obviously many. Two perhaps are of concern to us in the metrology community. Firstly, how do we maintain integrity, and improve uncertainties on measurements being made that are well understood i.e. power and energy, but where measurement conditions are now quite substantially different from those in the past. Secondly, how do we ensure adequate uncertainty measurements are made on some of the newer measurements being called for today, such as flicker.