Smart Grid and Enabling Technologies. Frede BlaabjergЧитать онлайн книгу.
1.7.5 Reliability and Power Quality
The SG utilizes technologies such as improved fault detection, state estimation, and enabling self‐healing of the network without the need for specialized personnel. This leads to a reliable supply of electricity and minimized vulnerability to attacks or natural disasters. Smart grid operates resiliently in disasters and during physical, or cyber‐attacks. Advanced control methods and monitoring oversee essential elements of the grid, enable rapid diagnosis and solutions to events that affect the grid's integrity, power quality, and smooth operation. The grid can monitor both on‐line and in real‐time as well as assess its current state and predict its future situation. The SG has robust risk warning procedures to employ preventive capabilities, automatic fault diagnosis, self‐fault isolation, and self‐restoration [48]. With all‐new energy resources and entities, optimization and handling the system will become more challenging, even with the availability of new technologies and tools. Interdependencies and interactions between distribution and transmission systems will keep rising. The increase in the grid's complexity will require many technological, computational, and business operation requirements such as [49, 50]:
1 Self‐learning systems.
2 Increased coordination between transmission‐level balancing areas as well as additional balancing abilities at the distribution level.
3 Balancing abilities using both load‐side and supply‐side operations.
4 Privacy and security to be applied in all parts of the system, down to end‐use devices.
5 PnP capabilities in SG enhanced levels.
1.7.6 Market‐Enabling
The SG enables systematic communication between suppliers (their price of energy) and consumers (willingness‐to‐pay) and allows both the consumers and supplier increasing transmission paths, aggregated supply, DR initiatives, and ancillary service provisions [51].
1.8 Transformation from Traditional Grid to Smart Grid
There is a huge need to transform the traditional grid structure to SG. The current electric grid is on the way to SG at various rates of acceleration. Much has been accomplished to mitigate the possibility of blackouts, especially in utilizing new technologies that can assist electricity grids to be more reliable. Many of these technologies are smart and widely deployed now, whereas others are still in the demonstration and planning stages. Advanced components are already being used to analyze and diagnose the grid state and assist in its healing within a limited period of time. Figure 1.17 shows the transfer process from the traditional grid to a SG which indicates moving from one‐way power flow (simple interaction) into two‐way power flow (multi‐interaction). A detailed comparison between the traditional power grid and SG are presented in Table 1.1. This shows that the majority of SG features are originated from the massive amount of generated information, an uncountable number of inter‐net‐connected control, and programmable auto‐operated equipment [52, 53].
1.8.1 The Necessity for Paradigm Shift to SG
Maintaining economic growth and improving the quality of human life are reliant on the availability of affordable and reliable electricity. Up to now, conventional grids function in almost the same way as those of 130 years ago, i.e. power flows in a single direction across the grid, from the central power plants to the customers. The reliability is maintained by conserving the excess capacity, which is inefficient, uneconomic, and environmentally unfriendly. Current grid topologies cannot be used with the distributed renewable energy sources and two‐directional power flow. The alternating nature of renewable energy sources creates additional challenges. The aging grid also faces new problems due to increased demand, and nonlinear loads. Such a grid experiences an inability when the demand for power delivery and consumption boosts, which has happened frequently worldwide in recent years. The main reason that acts on the decrease of the traditional power grid's reliability is the lack of information exchange [54]. The current grid is of limited ability to react quickly to handle congestion, instability, and power quality challenges. The inflexibility of the existing grid cannot support the high integration of renewable energy. These limitations can lead to blackouts, equipment outages, and unscheduled downtime. Approximately 90% of all power outages and disturbances have their origins in the distribution network, therefore, transforming to the SG paradigm ensures a significant improvement of the grid's reliability. Furthermore, electric utility customers currently have a passive role; they have no access to the real‐time consumption and pricing information that allow them actively participate within the power grids and optimize their energy usage and bills during peak and off‐peak times. The two‐way communication and power flow within the SG allow for effective energy control and energy management. This feature also allows achievement of both environmental and economic sustainability.
Figure 1.17 The difference between the conventional power grid and smart grid structure.
Table 1.1 A detailed comparison between conventional power grids and smart grids.
| Characteristics | Traditional grid | Smart Grid |
|---|---|---|
| Technology | ElectromechanicalMechanical devices electricity operatedNo communication between devicesLittle internal regulation | DigitalDigital devicesIncreased communication between devicesRemote control and self‐regulation |
| Flow of power and communication | One wayPower flow starts from the main plant using traditional energy structure to the customer | Two wayPower flow goes to and from various grid users |
| Generation | Centralized | Distributed |
| Fault location | Difficult to determine | Can be determined remotely as well as predicted |
| Monitoring | Manual | Self‐ monitoring |
| Equipment failure | System responds to deal with post failure and blackout incidents | Adaptive and can be isolated and automatically reconnected. |
| Control | Limited control system | Pervasive control system |
| Operation and maintenance | Manually equipment checks | Remotely monitor equipment |
In summary, transforming to SG paradigm will help in the wide‐scale integration of energy sources, enhancing network reliability, and improving power quality and load profile.