SMART COMMERCIAL FEATURE GRID TECHNOLOGY THE MPORTANCE By Kripa Venkat, Texas Instruments OF SUBSTATION AUTOMATION IN ENERGY GRID MANAGEMENT In the past few years, terminologies such as smart grid, grid intelligence, smart meters, grid infrastructure are being widely used. The purpose is to increase the efficiency and robustness of energy generation, transmission and distribution. Due to the ever increasing demand for energy, there have been several efforts to develop, and combine renewable and non-renewable sources of energy. The goal is to ensure uninterrupted and reliable availability of power/energy. In parallel, there are initiatives to increase awareness to save power, reduce carbon emissions, protect the environment and preserve natural resources. In developed countries, the grid has served very well for many decades, but needs an overhaul for the above mentioned reasons. In developing nations, there are huge investments in place for this overhaul, but things are slow-paced due to several regulations and bureaucratic delays. There are several examples that highlight the need for an overhaul of the current infrastructure; let’s look at some examples. In 2013, we had the Super Bowl black-out affecting half the stadium during the third quarter, North India black-out of 2012, and several others that repeatedly happen but don’t get on the front pages of global newspapers. Unfortunately, this affects the lives of millions of people, leading to chaos, accidents, loss of life and property. Efforts are being made by utility companies all over the world to ensure incidents like these are avoided. In most cases, black- outs are a result of rapid increased need for power, thus overloading the grid; however, natural disasters such as hazardous weather conditions might be unavoidable. Most recently, security requirements have gone up due to threats issued by terrorist organizations to dismantle the grid via hacking, malware and security breaches. We have already seen some of this in 2014 in areas outside of the energy grid. 56 Table 1 lists the differences between a conventional grid and a smart grid. It is interesting to note that there is a strong requirement for the grid to be smart in order to take advantage of the renewables as part of alternative sources of energy. Figure 1 shows a smart grid with distributed power generation from large solar and wind farms, as well as bidirectional flow from producer-customers of various sizes. Only an intelligent grid can integrate such widespread electricity generation from renewable sources, along with outputs from traditional large generating stations, and deliver power in real time to customers with varying requirements. This clearly reflects the need to build several distributed control centers called substations along the entire signal chain starting from the energy generation to the distribution. Substation automation is the best way to implement the intelligence required to manage the grid reliably and safely. It is important to note that there are several types of substations that encompass grid management, advanced sensing systems, protection systems, measurement systems etc. and all these combined with communication technologies form an automated control environment. Looking at the grid in Figure 1, we can see many substations installed moving from energy generation to distribution. These substations are localized power converters housing several transformers, capacitor banks, switches, relays etc. Supersets of these devices are called intelligent electronic devices (IED). IEDs include protection relays, power quality meters, circuit breakers, annunciators, fault indicators, phase controllers, VAR compensators, smart utility meters, arc-fault detectors, energy gateways, data concentrators etc. Integrated chips (IC) and electronics and silicon content that have the ability to sense, measure, protect and control make the grid smart. There has to be intelligent devices and automation at various stages of the grid for overall robustness. Beyond the grid infrastructure are inverters for solar and wind power, smart meters at commercial and consumer sites, and potentially limitless switches, sensors and monitoring units that feed information into the network. Years of silicon integration technology development, power density improvements and connectivity options (wired/wireless), have all made these additions cost-effective. Table 1: Difference between conventional grids and smarter grids METERING INTERNATIONAL ISSUE – 1 | 2015