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Submarine cables are indispensable for offshore wind farms (OWFs) connected to a power grid. The submarine cable can cause certain degrees of impact on the system performance due to its different lengths, characteristics, electrical parameters, etc. This paper employs the power-system simulation software of Power System Simulator for Engineering (PSS/E) for modeling a future-scheduled OWF, i.e., a large-scale doubly-fed induction generator-based OWF of 200 MW, connected to Jang-Bin distribution substation of Taiwan Power System through five feeders, five circuit breakers, two step-up power transformers, a commercial submarine cable, and an underground cable. This paper simulates and compares the electrical quantities of the studied OWF with different operating capacities under various lengths of three types of commercial submarine cable. The transient surge peak voltages at the common bus of the OWF and the bus of Jang-Bin distribution substation subject to the switching of one of the five circuit breakers of the studied OWF under different lengths of the three types of commercial submarine cable are also compared using the power-system simulation software of ATPDraw in Alternative Transients Program (ATP) version of Electromagnetic Transients Program (EMTP). [ABSTRACT FROM AUTHOR]

If an extreme contingency strikes the Kinmen Island power system in Taiwan, it is very likely to cause blackouts. Although an underfrequency protection scheme has been applied, some drawbacks of the protection scheme hinder the Kinmen power system from avoiding blackouts. In the past decade, several blackouts have occurred in the Kinmen power system. To avoid further possible blackouts, a special protection system (SPS) is summoned. This paper describes the design guidelines and deployment procedures of an SPS for the Kinmen power system. The design depends on the Kinmen power system characteristics, and the deployment hinges upon the supervisory control and data acquisition system. Exquisite software was also developed to testify the Kinmen system SPS. Operational records have demonstrated that the proposed SPS can indeed prevent blackouts from occurring in the Kinmen power system. The design, implementation, and operation of the SPS dealt with in this paper might foster further deployments of other SPSs. [ABSTRACT FROM AUTHOR]

The west coast and islands of Taiwan have abundant wind resource, which offers a great opportunity for large-scale offshore wind power generation. In Taiwan, the first stage of the offshore wind farms at the Jhang-Bin and Penghu areas has been planned. In particular, the Jhang-Bin wind farm will become the first and one of the largest wind farms in Taiwan. Therefore, its impacts on system operation and security have to be investigated and studied in advance. Following a general connection design discussion, this paper is consist of four major system impact analyses: load flow, fault current, voltage variation, and transient stability. Moreover, three types of typical wind turbines have been adopted in this paper in order to compare their performances on the wind farm integration system. From the simulation results, some significant conclusion and recommendations have been extracted, which would contribute to the first offshore wind farm development in Taiwan. [ABSTRACT FROM AUTHOR]

This paper presents both steady-state performance and dynamic simulations of a commercial wind farm (WF) in Taiwan through field measurement results and computer simulations. The companion paper in Part II discusses the dynamic and transient analyzed results of using current-limit reactors (CLRs) and load tap changers on power-quality improvement of the studied WF. With 23 2-MW DFIG-type wind turbine generators, this WF is connected to the 161-kV extra high-voltage substation of Taiwan Power System through a 23/161-kV 60-MVA step-up main transformer from six feeders with CLRs. Through comparing field measured results, this paper establishes a simulation model to simulate and analyze the steady-state and dynamic characteristics of the studied WF which is subject to disturbance conditions under different wind-speed conditions. [ABSTRACT FROM PUBLISHER]

This paper presents the effects of installing variable current-limit reactors (CLRs) and adjusting load tap changers (LTCs) on the performance of a commercial wind farm in Taiwan using computer simulations. The companion paper (Part I) demonstrates the field-measured results, simulation model, and simulation results of the studied Jang-Bin wind farm with 23 2-MW doubly fed induction generator-type wind turbine generators connected to the utility system through a 23/161-kV 60-MVA step-up main transformer (MT) from six feeders. Six CLRs, which were originally designed to limit short-circuit currents under faulted conditions, are connected in series with the six feeders. The LTCs of the MT are used to adjust/regulate the secondary-side voltage at the 23-kV bus. Some simulated steady-state and transient results of the studied wind farm with variable values of the proposed CLRs and LTCs are analyzed and compared. [ABSTRACT FROM PUBLISHER]

For isolated power systems, an efficient and effective ancillary services market is one of the most important tools to ensure the system security and service quality. It is recognized that pumped storage units can play a unique role in the operation of isolated power systems. As part of the introduction of the ancillary services for Taiwan, a study was performed to identify the role and value of pumped storage units in the fast-response reserve (FRR). This paper analyzes the actual dispatching schedules of pumped storage units in the Taiwan Power System (TPS) to provide FRR when system was operated under seriously insufficient conditions for the year 2004. The results are used to quantify the value of pumped storage units in the ancillary services. Since the dispatching schedules of pumped storage units determined the cost of FRR in the TPS, the actual operating experience of pumped storage units studied in this paper can be used to evaluate the impact on the system security and to further define the role of pumped storage units in the ancillary services market. [ABSTRACT FROM AUTHOR]

This paper investigates the power load composition of an isolated power system using a load survey and estimates wind power generation with a probabilistic network. The typical load pattern of various customer classes is derived, which are then used to derive the total power consumption of all customers within each class. A probabilistic neural network is used to solve the win power generation based on the wind speed for an offshore island in Taiwan. With the hourly wind speed and load composition, the power generation of diesel generators was obtained. Results of this paper demonstrate that wind power generation can economically and effectively replace the power generation of the island's diesel power plant and provide partial power-supply capability for the net peak load requirement. [ABSTRACT FROM AUTHOR]

This paper presents the design, implementation, and field measurements of a prototype marine-current power generation system (MCPGS) for capturing energy from marine current. The studied prototype MCPGS employs the flowing marine-current energy near the Cross-Sea Bridge, Peng-Hu Island, Taiwan. The design of the prototype MCPGS has to meet the practical marine-current flowing conditions and the severe environmental conditions in the ocean of Peng-Hu Island. The designed MCPGS unit consists of a three-blade marine-current turbine, a gearbox, a three-phase permanent-magnet generator, and a power converter that is used for converting generated energy to be stored in the battery. Field measured results for the studied MCPGS under different practical marine-current speeds in Peng-Hu Island are performed and analyzed. [ABSTRACT FROM AUTHOR]

As the consciousness of human beings in preserving the world increases, the demand of alternative energy resources has been expanding exponentially in recent years, and wind power is one of the most promising renewable energy resources. Taiwan, with its abundant coastal wind resources and good geographical conditions, is very suitable for developing wind farms. The development and implementation of renewable energy regulations have defined a direction for future renewable energy development in Taiwan. This also shows Taiwan's determination to follow the footsteps of the developed countries and the commitment to environmental protection. Therefore, the decision making of wind farms has become the most important link for the construction of wind farms in the future. This paper proposed a fuzzy analytic network process with benefit–opportunity–cost–risk approach to systemize the complicated decision making of wind farm site selection. A case study is carried out to examine the proposed approach and to evaluate the performance of several existing wind farms in Taiwan. By adopting the systematic analysis method, the most suitable wind farm can be determined, and the results can be references for planning and development of wind power industry in the future. [ABSTRACT FROM AUTHOR]

The ultimate goal of an electric utility is to create maximum profit while maintaining reliability and security of the power supply. The operation and control of power system is sensitive to system demand. Therefore, improvements in load-forecasting accuracy will lead to cost savings and enhance system security. Due to Taiwan's distinct climate characteristics, it is difficult to obtain satisfactory load-forecasting results by treating the whole island as a single region. In addition, weather factors, such as temperature, relative humidity, and the Heat Index (HI) (a human-perceived equivalent temperature) may also affect load-consumption patterns. This paper proposes a multiregion short-term load-forecasting methodology, taking into account the HI to improve load-forecasting accuracy in Taiwan Power Company's (Taipower's) system. The results show that adopting the HI as a parameter can effectively improve the accuracy if the temperature of the region under investigation is above 27 ^\circ\C (80 ^ \circ\F). By considering both the load/weather diversity and the HI, further improvements to the load forecasting for the Taipower system during summer can be achieved. [ABSTRACT FROM AUTHOR]

This paper presents the protective relay settings of tie line tripping and design of load-shedding scheme for an integrated steelmaking industrial power system to ensure system stability after a severe fault contingency on an external utility power network. The transient stability analysis of the industrial power system with the equivalent external Taipower system has been executed for an actual fault contingency in 2005. The mathematical models of 13 cogeneration units in the plant and several large generators of a nearby Taipower thermal plant are included in the computer simulation to solve the system transient response for the fault contingency to verify the accuracy of the models used. To prevent tripping of critical loads due to an external fault contingency, the undervoltage and under/overfrequency relays with proper settings are applied for the tripping of external and internal tie lines. To restore system stability of the industrial power system for the islanding operation after tie line tripping, load shedding is designed to disconnect a proper amount of noncritical loads by considering the governor response and protective constraints of cogeneration units. According to the transient stability analysis of the industrial power system with the proposed protective relay settings and load-shedding scheme, it is found that the voltage sag and oscillation problem caused by fault contingency in the external Taipower system can be mitigated if the tie line tripping is executed in time to prevent the shutdown of critical loads and tripping of cogeneration units. [ABSTRACT FROM AUTHOR]