Time Factor for Determination of Power Supply System Efficiency of Rural Consumers

Introduction

Many scientists have been engaged in the problem of determining power supply system efficiency of rural consumers. Recently, researchers have made a number of mathematical models that allow solving negotiation problems of agricultural enterprises and power companies.

So far, however, there is no detailed analysis of the concept of power supply system efficiency or power supply efficiency, despite the fact that these terms are widely used. The concept of «power supply quality» is also used, but the interpretation is always different depending on the sources. Most commonly, this concept is understood as a set of parameters for power supply reliability and power quality (PQ), sometimes with addition of power transmission efficiency. Economic indicators, such as payback period, profitability, etc., are often referred to as efficiency. Thus, it creates the circumstances where power supply system efficiency is understood as various indicators or their combinations. Therefore, developing universal criteria of power supply system efficiency allows a uniform interpretation of this concept in various scenarios.

The development of these criteria is impossible without introduction of the concept of «power supply system efficiency». The following interpretation is suggested: “Power supply system efficiency is a characteristic of a set of sources and systems of conversion, transmission and distribution of electric energy from the perspective of providing consumers with electric power at the lowest possible expenses under observance of specific PQ parameters and power supply reliability, along with the terms and technological connection (TC) quality”.

The analysis of power supply system efficiency of rural consumers is a difficult task because the systems are diverse. This variety resides in their structure, scale, types and capacities of consumers connected to them. The regulations and legal documents standardize the time parameters that characterize power system operation. There are three main parameters: power supply outage time as a performance criterion for power supply reliability; PQ inconsistency time with regulation requirements as a performance criterion for supplied power quality; and lastly, implementation time of technological connection to electric networks as a performance criterion for the power supply system development.

Therefore, the aim of this paper is to develop a mathematical model for the efficiency of power supply system of rural consumers. The basis for the analysis is the time criteria that characterize power supply reliability, power supply system development and power quality.

There are four primary objectives of this research:

• 1.

  To analyze the concept of power supply system efficiency, the criteria for its evaluation and to identify their structure and the values of the time criteria.

• 2.

  To develop a mathematical model for presenting the efficiency of power supply systems; the model takes into account the time criteria that characterizes power supply reliability, power supply system development and power quality.

• 3.

  To analyze the constituents of power supply outage time, PQ inconsistency time with regulation requirements, TC implementation time on electric networks.

• 4.

  To propose a set of technical and organizational measures to improve power supply system efficiency by reducing power supply outage time, PQ inconsistency time with regulation requirements, TC implementation time to electric networks.

Background

The issue of efficiency is a priority in the development and operation of any system. Power supply systems are not an exception. Many scientists, who have been engaged in this subject, have proposed a number of mathematical models that solve negotiation problems of agricultural enterprises and power companies. Moreover, these scholars have considered various aspects of power supply system efficiency. They have also determined indicators of power supply system reliability for different regions and countries and have done much work to assess power quality.