Frequency Operating Standards and Frequency Regulation - Report Example

Name Course Lecturer Date Frequency operating standards and frequency regulation in the NEM Abstract The Australian National Electricity Market has set frequency standards that its electricity operates. These standards help the National Electricity Market to ensure that the electricity that it is supplying to its customers is checked and monitored so that in case there are extreme fluctuations above and below the set operating standards, the body in charge of the frequency regulation comes in to intervene. The key factors that have been identified as being responsible for these fluctuations are the supply and demand situations of the market. It has been recorded that when the demand for electricity is high, the frequency drops and when the demand for electricity is low, the frequency increases. This report focuses on the electricity situation in Mainland Australia. The data collected every second on the date of 9th July 2017 is going to be analyzed statistically so that the fluctuations can be appreciated and once this is done, the National Electricity Market will appreciate the frequency regulation aspect of the electricity. Introduction The set frequency range that the National Electricity Market in Australia (NEM) operates is around 50 Hertz. This range underpins the reliable, secure and safe power transmission through the Australian electricity supply chain that starts from generators and end with consumers. In order to control the frequency of the power system, there is need to have constant balancing of electricity demand and supply. This means that if the supply of electricity is more than the demand at a given point in time, there will be increase in the frequency of power system. On the other hand, if the demand for the electricity is more than supply at a given point in time, then the frequency of power system will decrease. In case the change is too big, load and generation can be disconnected, in other words load shedding will take place. The frequency in the power system that is interconnected is normally the same throughout. Australia National Electricity Market (NEM) is among the largest interconnected power line systems globally. The organization power lines run from Port Douglas in Queensland to Port Lincoln in Southern part of Australia, a distance of about five thousand kilometers (AEMO, n.d). It started operating as wholesaler of electricity to consumers in 1998 to consumers in South Australia, victoria, Queensland, Australia Capital Territory and some other parts of Australia. Exchange between the producers and consumers of electricity is facilitated by a means of a pool whereby the power output from all generators is aggregated and scheduled at an aim of meeting consumers demand. The pool is not something physical, but instead it is a set of rules that Australian Energy Market Operator (AEMO) manages in accordance with the provisions of National Electricity Laws and together with market regulatory agencies and other market participants (AEMO, n.d). AEMO was set up in 2009 in order to manage NEM and gas markets in Australia. Its main functions are energy market development, transmission services, national transmission planning, and electricity market. This laboratory assignment focuses on the aspect of frequency regulation as well as frequency operating standards in NEM. In order to achieve this, statistical analysis will be carried on the frequency of the mainland power system as well as the distribution of this frequency. Some of the things to be done include plotting a chart that will show they way frequency fluctuates on Mainland Australia, the descriptive statistics of the frequency in Mainland Australia. Frequency Operating Standards Electricity power frequency standard in Australia is managed by AEMO. The standard of NEM power frequency is 50 Hertz; at this frequency it is safe, secure and reliable to transmit power through supply chains from production generators to end market consumers. The power frequency must be controlled for the reasons mentioned above and controlling needs constant balancing of supply and demand. Excess supply and high demand change power frequency. NEM power frequency is the same throughout the system. The NEM electricity frequency standards are set by reliability panel, the panel is appointed and convened by Australian Energy Market Commission (AEMC) (Australian Energy Market Operator, 2017). When it comes to matters of frequency control, the panel is tasked with prescribing maximum acceptable frequency deviations for different types of operating conditions. Frequency Regulation Process AEMO must always maintain power system security by balancing power supply and demand so as to make sure that power flows remain within the grid technical limits. If the power operates outside the set technical limits, there is a risk ranging from electric disruption in the market all the way to disconnection in power generating plants and stations, plant damages, and blackouts in some areas (Australian Energy Market Operator, 17). For AEMO to maintain power security, they require accurate and up to date information that includes real-time data on the status of important power system components, amount of generated power, and power flows on power lines and performance standards and model for main elements in the system such as transformers. Operation process to maintain power system involves central dispatch process, frequency control, voltage control, and network management flow (Australian Energy Market Operator, 20). AEMO manages the whole market by a centrally coordinated dispatch process that pools power from the generators and deliver the needed power to the wholesalers. For this to be achieved there are certain activities that needs to be carried out and this includes managing the bidding, determining spot price, measuring the amount of power being used, and scheduling and dispatching of generators (Australian Energy Market Operator, 21). The process of dispatch operates on a 5 minutes cycle and dispatch scheduled generation together with forecast non-scheduled generation and semi-scheduled generation will end up matching forecast demand from main transmission (Australian Energy Market Operator, 277). Spot market operations timetable sets the dates, times, frequency and period covered by data to be provided to those who take part in the operation of spot market. NEM has a dispatch engine (NEMDE) which is a form of software used by AEMO to make sure that the central dispatch process maximizes value for trade. The aim of the central dispatch is to ensure that power produced meets the required demand and it also coordinates power generation capacity to be in a position of responding to changes quickly. Frequency levels can be controlled depending on the level of deviation. Frequency control ancillary services (FCAS) increases or decreases output in short notice. The system ancillary services automatically detect small deviations of frequency and the sends increase or decrease frequency signal to the generating station so as to correct the deviation (AEMO, n.d). The small deviations in the electricity frequency develop as a result of several reasons that create small mismatches between generation and demand. These factors include aggregate variations in solar or wind generation output between the dispatch interval and generated power not being in a position of meeting the required dispatch. Contingency FCAS respond to large power frequency deviation. FCAS providers respond to find a correction for frequency deviations developing from large supply demand imbalances that come as a result of sudden network breakdown or disconnection of load from power system (AEMO, n.d). FCAS contingency services is divided into increase and reduce services at 3 different speeds of response that is 6, 60, and 5 minutes. Examples of FCAS providers are generator governor response, in this situation the generator governor reacts to deviation of frequency by closing or opening turbine steam. Load shedding is a situation in which load is disconnected from the electric system. And finally is rapid generation response in which frequency relay will detect a low frequency and immediately start a generator (AEMO, n.d). Real Life Case A real life situation in which power system frequency violated the normal working frequency was in 2007 in Australia, victoria. The incidence happens in an interconnected power system during a bush fire. When the incidence happens, victoria region was an island from the NEM mainland and approximately quarter of the load was shed by Under Frequency Load Shedding Scheme. After the happenings it took many hours before the load was restored. The reconnection of shade load was limited by the shortage of contingency reserves to cover the loss. The consequences were that it resulted in blackout in some areas and some electrical machines and appliances in many industries and house was affected, some just went off while other broke down completely (Gans and Stephen 32). Statistical Analysis Chart Showing Frequency Fluctuation on Mainland Australia According to the above chart, the frequence fluctuates so close to 50 Hertz and within the day, it flattens out . Mean, Standard Deviation NEM FREQUENCY 9th July 2017 Mean 50.00229 Standard Error 0.000197 Median 50.00305 Mode 50 Standard Deviation 0.028938 Sample Variance 0.000837 Kurtosis 5.614184 Skewness -0.23342 Range 0.27 Minimum 49.87 Maximum 50.14 Sum 1080099 Count 21601 Bar Histogram Bin Frequency 49.05 0 49.06 0 49.07 0 49.08 0 49.09 0 50 3388 50.01 15903 50.02 0 50.03 663 50.04 0 50.05 569 50.06 0 50.07 512 50.08 0 50.09 186 More 380 Bin Histogram Bin Frequency 49.8 0 49.82 0 49.83 0 49.85 0 49.86 0 49.88 9 49.89 126 49.91 293 49.92 166 49.94 440 49.95 0 49.97 599 49.98 710 50 1045 50.01 15903 50.03 663 50.04 0 50.06 569 50.07 512 50.09 186 50.1 242 50.12 123 50.13 0 50.15 15 More 0 Conclusion From the statistic analysis a number of observations can be made. The data that was used was the real life data of the Mainland Australia. In the introduction, it was shown that the Australia’s National Electricity Market operates within a given frequence range, which is approximately 50 Hertz (Hz). However, on analysing the real life data, it is evident that some frequencies fall outside the 50 Hertz. It was shown that it is the demand and supply for the electricity that causes these adjustments or fluctuations in the electricity. The statistical analysis can be of great help to the Australia’s National Electricity Market. This is because it shows the organization that there are times that the frequency of transmission is falling outside the set range and once the organization comes to know about this, it will look at the factors that are causing this fluctiation. In conclusion, when it comes to Frequency operating standards and frequency regulation in the NEM, the use of statistical analysis is very critical in appreciating the way the electricity frequency data behaves in Australia. The analysis constitute the basis of research into the factors that lead to these fluctuations and hence the way this can be regulated (Steiner 16). References Gans, Joshua S., and Stephen P. King. "Options for electricity transmission regulation in Australia." Australian Economic Review 33.2 (2000): 145-160. Australian Energy Market Operator. Australian Energy Market Operator. [online] Available at: https://www.aemo.com.au/Electricity/National-Electricity-Market-NEM/Security-and-reliability/Dispatch-information [Accessed 26 Aug. 2017]. Steiner, Faye. "Regulation, industry structure, and performance in the electricity supply industry." (2000). AEMO.(n.d). Frequency control. Fact Sheet AEMO.(n.d). Visibility of the power system.Fact Sheet Read More

The pool is not something physical, but instead it is a set of rules that Australian Energy Market Operator (AEMO) manages in accordance with the provisions of National Electricity Laws and together with market regulatory agencies and other market participants (AEMO, n.d). AEMO was set up in 2009 in order to manage NEM and gas markets in Australia. Its main functions are energy market development, transmission services, national transmission planning, and electricity market. This laboratory assignment focuses on the aspect of frequency regulation as well as frequency operating standards in NEM.

In order to achieve this, statistical analysis will be carried on the frequency of the mainland power system as well as the distribution of this frequency. Some of the things to be done include plotting a chart that will show they way frequency fluctuates on Mainland Australia, the descriptive statistics of the frequency in Mainland Australia. Frequency Operating Standards Electricity power frequency standard in Australia is managed by AEMO. The standard of NEM power frequency is 50 Hertz; at this frequency it is safe, secure and reliable to transmit power through supply chains from production generators to end market consumers.

The power frequency must be controlled for the reasons mentioned above and controlling needs constant balancing of supply and demand. Excess supply and high demand change power frequency. NEM power frequency is the same throughout the system. The NEM electricity frequency standards are set by reliability panel, the panel is appointed and convened by Australian Energy Market Commission (AEMC) (Australian Energy Market Operator, 2017). When it comes to matters of frequency control, the panel is tasked with prescribing maximum acceptable frequency deviations for different types of operating conditions.

Frequency Regulation Process AEMO must always maintain power system security by balancing power supply and demand so as to make sure that power flows remain within the grid technical limits. If the power operates outside the set technical limits, there is a risk ranging from electric disruption in the market all the way to disconnection in power generating plants and stations, plant damages, and blackouts in some areas (Australian Energy Market Operator, 17). For AEMO to maintain power security, they require accurate and up to date information that includes real-time data on the status of important power system components, amount of generated power, and power flows on power lines and performance standards and model for main elements in the system such as transformers.

Operation process to maintain power system involves central dispatch process, frequency control, voltage control, and network management flow (Australian Energy Market Operator, 20). AEMO manages the whole market by a centrally coordinated dispatch process that pools power from the generators and deliver the needed power to the wholesalers. For this to be achieved there are certain activities that needs to be carried out and this includes managing the bidding, determining spot price, measuring the amount of power being used, and scheduling and dispatching of generators (Australian Energy Market Operator, 21).

The process of dispatch operates on a 5 minutes cycle and dispatch scheduled generation together with forecast non-scheduled generation and semi-scheduled generation will end up matching forecast demand from main transmission (Australian Energy Market Operator, 277). Spot market operations timetable sets the dates, times, frequency and period covered by data to be provided to those who take part in the operation of spot market. NEM has a dispatch engine (NEMDE) which is a form of software used by AEMO to make sure that the central dispatch process maximizes value for trade.

The aim of the central dispatch is to ensure that power produced meets the required demand and it also coordinates power generation capacity to be in a position of responding to changes quickly.

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