Mainland Frequency Analysis - Assignment Example

MAINLAND FREQUENCY ANALYSIS Name: College: Course: Tutor: Date: Mainland Frequency Analysis Review the frequency operating standards in the NEM and AEMO’s centrally coordinated dispatch process. Hint: AEMO’s website would be a good resource for this. Review the basics of the frequency regulation process in the NEM. Discuss Frequency Control Ancillary Services (FCAS) in the NEM. Identify and discuss one real-life case where the power system frequency violated outside the normal frequency operating range. What were the consequences? Table of contents Summary Introduction Liberalization of the power generation sector and the increased deployment of power sourced from large-scale renewable power plants have raised concerns regarding the dynamism of power flows. The complexities associated with such dynamism have enhanced need for situational awareness on a real-time basis and in turn, necessitated the management of power flow that is more coordinated (Volk 2013). Indeed, energy markets have undergone major transformation over time as the generation technologies evolved and their proportion of contributions into the energy market changed as well. In the early configurations of the energy market, electric power was sourced mainly from hydro, gas, coal and nuclear power plants also known as The responsibility of ensuring that the power system is operating safely and reliably lies in the hands of the AEMO as mandated under the National Electricity Rules. AEMO undertakes to regulate the amount and quality of the electricity energy through supplementing their mandate with ancillary services. They do not seek these services except if the law provides them since they have a cost impact on electric power. The rules give them the responsibility of incorporating the ancillary services so that they may ensure that the power voltage are within limits and within the shortest time ranges stipulated in the rules. Frequency operating standards The National Electricity Market is regulated by the frequency operating standards whose application is usually facilitated by AEMC (Australian Energy Market Commission) under the National Electricity Law (Sec. 38). Also, the law mandates the Reliability Panel to review the operating frequency standards so as to compliment on the ongoing projects and the status of energy production and distribution across Australia. The NEM mainland operating frequency standards for interconnected systems applies to any pert of Mainland power system. The current accumulated time error is 5 seconds. The standard also provides that containments of 49.75 to 50.25 Hz and 49.85 to 50.15 Hz during a no contingent event or load to be stabilized or recovered within 5 minutes to the normal frequency of between 49.85 to 50.15. In addition, during generation event, if the containment of the frequency is within 49.5 to 50.5 Hz it should be stabilized within 5 minutes. For the network event, the stabilization should be between 49.5 and 50.5 Hz within 1 minute and recovery can take up to 5 minutes. During the multiple contingency event, stabilization and recovery should be within 2 minutes and 10 minutes respectively. The frequency operating standards are facing the numerous challenges that are associated with market dynamics and technology. The increasing use of energy and the growing Australia’s population have necessitated the need of changing some aspects of the standard so as to ascertain the new know-how of energy investment. The growth of energy is plummeting while the demand is at its peak. The dynamics of the NEM have seen the development of an Electricity Statement of Opportunity which seeks to provide a new outlook of the NEM’s capacity for the period 2012-2022. The ESOO provides an outline of how the 13000 MW of electricity will be produced through wind energy. Therefore, the technological changes and the growing demand for energy is shaping the provisions of the frequency operating standards and at some point, the normal frequency of energy supply keep fluctuating and by 2022, the present standard frequency ranges will have changed. Frequency regulation process in the NEM There are three major categories of ancillary services; FCAS, NSCAC or SRAS. The frequency ancillary services and others are function-specific and each help in managing a certain condition that exists within the power system. To start with, FCAS are basically provided whenever the frequency goes above or is below the standard ranges. These services help to restore (in case of violation of frequency ranges) or maintain the levels within the acceptable ranges. On the other hand, the Network Support and Control Ancillary Services (NSCAS) are provided to regulate the amount of voltage among networks to ensure that the dispatch follows the correct directions. As a result these ancillary services bring about harmony in the network power system. Lastly, the System Restart and Ancillary Services (SRAS) are usually exploited as contingence input during an unexpected power blackout. Frequency Control Ancillary Services (FCAS) in the NEM The FCAS have been established to ensure that it balances the demand and supply of power within the NNEM frequency standards. There are two categories of frequency control which include regulation frequency and contingency. Regulation frequency control This can be defined as the process of correcting the non-equilibrium that exists during the generation and supply of power. The gap that may exists between demand and supply constitute the inequilibrium state and this is very critical in power supply. AEOM has two control centers that oversee the regulation of the amount of voltage that is being supplied into the power system. While regulation is centrally achieved by AEMO, the control services are however, provided by the Automatic Generation Control. Importantly, the significance of this system is that it provides AEMO with the capacity to monitor the power system’s frequency. It also facilitates the issuance of signal to the regulatory system to restore and maintain the system’s acceptable frequency ranges of between 49.85 and 50.15. Contingency frequency control The normal standard frequencies can sometimes be violated not necessarily due to human behavior, but natural disasters. Therefore, such situation of unexpected calamities that may cause disorder in the power system requires that there be a contingency measure that would ensure that the normal ranges are restored. The contingency frequency control is applied during a contingent event to restore the balance between generation and supply of power. An example of a contingent event may include major industrial load or even loss of generating unit. The standards articulate the role of AEMO at the time of a contingent event. It stipulates that the body should oversight the system and be able to identify contingent events and correct the frequency deviation. The effectiveness of the AEMO’s response to contingency events relies on the nature of technologies and their capacity to detect any abnormal frequencies in the power network. On tis note, the Generator Governor Response is used as the most effective technologies in contingency frequency control. Also, the “load shedding” can be used to correct low frequency situations. Other technologies such as the Rapid Generator which automatically restores the low frequency that may be noticed are also used. Generally, the power system is more complex to comprehend but various regulatory systems that are in place facilitates the automatic evaluation of and restoration of frequency ranges. The dispatch process operates on a five minute cycle and dispatches scheduled generation which, in combination with forecast non-scheduled generation (generally generation under 30 megawatts (MW)) and semi-scheduled generation (intermittent generation such as solar and wind), will match forecast demand from the transmission grid. The central dispatch process aims to match electricity supply to electricity demand, as well as coordinate the generation capacity to be able to quickly respond to changes. This is done through a market mechanism which AEMO uses to ensure the available ancillary services sufficiently help in the management of output. Although any technology can participate in the FCAS market if technically capable, these services have generally been provided by thermal (such as coal and gas) and hydro generation. One real-life case The Violation of Power Frequency Operating Standards in Tasmania In 2011, there existed an AEMO’s system fault where the dispatch system failure resulted into incorrect dispatch frequency targets being received by Basslink. The net impact was observed in the frequency distribution in Tasmania falling outside the normal ranges as provided by the standards. Furthermore, the recovery process did not take place within the stipulated recovery time. Further investigations also revealed that the setpoint receiver of the Norwest Automatic Generation Control system also failed to send correct dispatch targets to Murraylink. The resulting event was that the negative dispatch targets were blocked. The correction process was however, successful as both the AEMO and Basslink operators applied the recovery procedures as required. AEMO revoked the non-conformance constraint and also transferred the AGC function to the Mansfield control center. The consequences of the event were not substantial as the situation was normal at Tasmania. The consequences that faces the energy regulatory bodies is that the power systems contravened the provisions of the frequency operating standards. Hence, there is a legal implication. Nonetheless, the high voltage distribution of energy increases the risks of exposure to electromagnetic field which in turn affects the health of human beings. Also, the high frequency could lead to household damages and also high cost of power. Statistical analysis Frequency for fluctuation The Mean Value of Frequency and Standard Deviation The mean value= Sum of Fk*x, where Fk = n/N The mean value has been calculated using excel and the value is 50.0026. The table for as shown below. Standard deviation of the mean= 2.17 Standard deviation of frequency= 0.104 A Bar Histogram of Number of times each Frequency was observed Chart of Frequency in Fraction Gauss Distribution The Australia’s Mainland frequency takes a belly-like shape which indicates that it follows a normal distribution. The Gauss distribution limits the distribution of frequency in Mainland. Conclusion Frequency regulation is paramount and a significant part of secure electric power generation and supply. The need for regulating the energy frequency is wanting since there is a growing demand for sustainable energy production. The frequency operating standards is the central hub for quality and quantity control of energy supply. Notably, the current frequency operating standards reflect the modern interventions and guidelines of ensuring appropriate contingent measures are followed during abnormal frequency ranges. The sets of procedures are very clear in regard to response, stabilization and recovery times required for particular events. It should be noted that when the energy voltage is not within the normal ranges, it could have impact on the transmission capacity of cables that distribute electricity power to the households and can expose them to a very risky situation. There is also a link between the price of ancillary services and the violation of the normal frequency ranges. However, the voltage going beyond the set targets is common and this is usually caused by power system failures and other natural factors. That said, it is the responsibility of the energy regulatory bodies to ensure that the frequencies are within the normal ranges. Reference Gannon, M., Swier, G. and Gordon, R., 2014. Emerging Rate-of-Change-of-Frequency Problem in the NEM-Best-practice Regulatory Analysis of Options. University of Melbourne, Melbourne, 31. Riesz, J., Gilmore, J. and MacGill, I., 2015. Frequency control ancillary service market design: Insights from the australian national electricity market. The Electricity Journal, 28(3), pp.86-99. Nepal, R. and Foster, J., 2016. Testing for market integration in the Australian National Electricity Market. The Energy Journal, 37(4), pp.215-238. Read More

In addition, during generation event, if the containment of the frequency is within 49.5 to 50.5 Hz it should be stabilized within 5 minutes. For the network event, the stabilization should be between 49.5 and 50.5 Hz within 1 minute and recovery can take up to 5 minutes. During the multiple contingency event, stabilization and recovery should be within 2 minutes and 10 minutes respectively. The frequency operating standards are facing the numerous challenges that are associated with market dynamics and technology.

The increasing use of energy and the growing Australia’s population have necessitated the need of changing some aspects of the standard so as to ascertain the new know-how of energy investment. The growth of energy is plummeting while the demand is at its peak. The dynamics of the NEM have seen the development of an Electricity Statement of Opportunity which seeks to provide a new outlook of the NEM’s capacity for the period 2012-2022. The ESOO provides an outline of how the 13000 MW of electricity will be produced through wind energy.

Therefore, the technological changes and the growing demand for energy is shaping the provisions of the frequency operating standards and at some point, the normal frequency of energy supply keep fluctuating and by 2022, the present standard frequency ranges will have changed. Frequency regulation process in the NEM There are three major categories of ancillary services; FCAS, NSCAC or SRAS. The frequency ancillary services and others are function-specific and each help in managing a certain condition that exists within the power system.

To start with, FCAS are basically provided whenever the frequency goes above or is below the standard ranges. These services help to restore (in case of violation of frequency ranges) or maintain the levels within the acceptable ranges. On the other hand, the Network Support and Control Ancillary Services (NSCAS) are provided to regulate the amount of voltage among networks to ensure that the dispatch follows the correct directions. As a result these ancillary services bring about harmony in the network power system.

Lastly, the System Restart and Ancillary Services (SRAS) are usually exploited as contingence input during an unexpected power blackout. Frequency Control Ancillary Services (FCAS) in the NEM The FCAS have been established to ensure that it balances the demand and supply of power within the NNEM frequency standards. There are two categories of frequency control which include regulation frequency and contingency. Regulation frequency control This can be defined as the process of correcting the non-equilibrium that exists during the generation and supply of power.

The gap that may exists between demand and supply constitute the inequilibrium state and this is very critical in power supply. AEOM has two control centers that oversee the regulation of the amount of voltage that is being supplied into the power system. While regulation is centrally achieved by AEMO, the control services are however, provided by the Automatic Generation Control. Importantly, the significance of this system is that it provides AEMO with the capacity to monitor the power system’s frequency.

It also facilitates the issuance of signal to the regulatory system to restore and maintain the system’s acceptable frequency ranges of between 49.85 and 50.15. Contingency frequency control The normal standard frequencies can sometimes be violated not necessarily due to human behavior, but natural disasters. Therefore, such situation of unexpected calamities that may cause disorder in the power system requires that there be a contingency measure that would ensure that the normal ranges are restored.

The contingency frequency control is applied during a contingent event to restore the balance between generation and supply of power. An example of a contingent event may include major industrial load or even loss of generating unit. The standards articulate the role of AEMO at the time of a contingent event.

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