Abstract
Содержание
- Introduction
- 1. Theme urgency
- 2. Goal and tasks of the research
- 3. Optimization of the modes of electrical networks with a high degree of heterogeneity
- 4. Optimize power distribution by reactive power compensation
- Conclusion
- References
Introduction
One of the main indicators of energy efficiency is the technological costs associated with its transportation from power sources to consumers.
The main reason for the increased energy consumption is the low efficiency of energy-saving measures, which is due to the insufficient level of automation in the control and management of main and distribution power grids.
1. Theme urgency
The master's work is devoted to the actual scientific problem of optimizing power flow distribution using various possible methods and analyzing their strengths and weaknesses. The main research tool is the PowerFactory software, which analyzes the modes of modern power systems.
2. Goal and tasks of the research
The aim of the study is to study methods for optimizing power flow distribution in electric networks with a voltage of 35-110 kV.
Main tasks of the research:
- Analysis of the main methods for optimizing power flow distribution.
- Assessment of their advantages and disadvantages for the studied network area.
- The application of the event of splitting a closed circuit at the point of the flow divide, for the real section of the electric power network.
- The economic rationale for methods of optimizing flow distribution.
- Analysis of the impact of these methods on the network mode parameters (voltage, loss).
Research object: change in power flows in the area of the electricity network.
Research subject: section of the electrical network in the implementation of optimization methods in the environment of the program PowerFactory.
3. Optimization of the modes of electrical networks with a high degree of heterogeneity
One of the main reasons for the non-optimality of the regimes of electric power systems and additional losses of electric power during its transportation and distribution is the heterogeneity of electric power systems [1,2].
Inhomogeneity of networks is an unfavorable flux distribution in developed high-voltage networks associated with the difference in inductive conductivity ID = X / R for lines of different voltages [3].
The heterogeneity of electric power systems leads to negative phenomena:
- decrease in power quality;
- additional network load of lower voltage levels;
- reduce the level of static and dynamic stability of power systems (which in turn reduces the throughput of the system as a whole) [4-6].
Optimization of the natural distribution of power flows in closed networks can be achieved in the following ways:
- The inclusion in the contours of the network of longitudinal compensation.
- Inclusion of longitudinally transverse booster transformers in the circuit.
- Open loop closed network and the transition to an open circuit.
4. Optimize power distribution by reactive power compensation
Reactive power compensation is made thanks to synchronous compensators, capacitor banks.
1. A synchronous compensator is a synchronous motor that operates in idle mode, that is, with virtually no active load on the shaft.
Figure 4.1 – Enable synchronous compensator
The advantages of synchronous compensators:
- the possibility of increasing the generated power while reducing the voltage in the network by regulating the excitation current;
- possibility of smooth and automatic control of reactive power.
After installation at the end of the line at the consumer of compensating installations (fig. 4.1) the line is unloaded by reactive power, the cosφ increases and the losses in the line decrease [7].
2. Capacitor batteries are made up of individual capacitors, which are connected in series and in parallel.
Figure 4.2 – Enable capacitor battery
Capacitor batteries are used:
- to generate reactive power in network nodes – transverse compensation;
- to reduce inductive resistance of power lines – longitudinal compensation.
Аdvantages:
- simplicity of the device and its maintenance;
- the absence of rotating parts provides safety maintenance;
- low active power loss.
The influence of different power levels of the capacitor bank on the power losses and the level of the voltage drop, for the simplest network, is shown in fig. 4.3.
Figure 4.3 – The effect of different capacitor bank powers on power loss and voltage drop level for the simplest network
(animation: 16 frames, 8 cycles of repeating, 21 kilobytes)
Conclusion
The analysis performed in the master's thesis allows us to conclude that the use of optimization methods in electric power systems allows us to increase the reliability of the power system, reduce energy losses and increase the voltage level near consumers.
In the framework of the research carried out:
- based on the analysis of literary sources, the main options for optimizing power flow distribution are highlighted;
- for the real part of the electric power system modeled in the PowerFactory software environment, the measures of splitting a closed circuit at the point of flow distribution were applied;
- economic justification of flow distribution optimization methods was carried out;
- а preliminary analysis of the main methods for optimizing the flow distribution of power has been carried out.
This master's work is not completed yet. Final completion: May 2019. The full text of the work and materials on the topic can be obtained from the author or his head after this date.
References
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