Qiteng Hong

Standardization of power system protection settings using IEC 61850 for improved interoperability

One of the potential benefits of smart grid development is that data becomes more open and available for use by multiple applications. Many existing protection relays use proprietary formats for storing protection settings. This paper proposes to apply the IEC 61850 data model and System Configuration description Language (SCL), which are formally defined, to represent protection settings. Protection setting files in proprietary formats are parsed using rule-based reasoning, mapped to the IEC 61850 data model, and exported as SCL files. An important application of using SCL-based protection setting files is to achieve protection setting interoperability, which could bring multiple compelling benefits, such as significantly streamlining the IED configuration process and releasing utilities from being “locked in” to one particular vendor. For this purpose, this paper proposes a uniform configuration process for future IEDs. The challenges involved in the implementation of the proposed approach are discussed and possible solutions are presented.

Intelligent system for detecting “hidden” errors in protection settings

Due to many developments taking place within the electricity supply industry, the network and its operation has grown ever more in recent years, which brings significant challenges for power system protection engineers. Apart from the significant efforts that are required to ensure that the protection setting process is effective, work also needs to be carried out to check the validity of the settings after initial calculation and application. However, solely relying on personnel and procedures to assess the validity of the protection relay setting files may occasionally result in a hidden error (or errors) remaining undetected until an in-service mal-operation event is experienced. This may bring significant consequences, in terms of economic costs, potential safety hazards and damage to the reputation of the utility company. This paper will present the initial research of making use of artificial intelligence technology (expert system) to help protection engineers validate the protection settings. Existing expert systems for protection settings applications will be reviewed and a new intelligent system that can open a setting file and interrogate the protection functions and settings in the file will be introduced. The advantages of this novel intelligent tool over existing protection setting expert systems will be discussed.

Application of a MW-scale motor-generator set to establish power-hardware-in-the-loop capability

This paper presents a Power-Hardware-in-the-Loop (P-HiL) testbed coupled to a MW-scale Motor-Generator (MG) set. The P-HiL configuration interfaces an 11 kV physical distribution network with a transmission network modeled in a Real Time Digital Simulator (RTDS) through the MG set. Uniquely, and in contrast with other P-HiL arrangements, the MG set used is equipped with a proprietary frequency controller with an inherent response that does not provide the desired characteristics to cater for a P-HiL interface. The paper describes a methodology to tackle this problem associated with undesirable response of the MG sets existing controller by introducing additional frequency and phase control loops. Experimental results are presented and show that the P-HiL testbed is capable of maintaining a high level of synchronization during disturbances and allows the power interaction between the model and physical network. The testbed offers a realistic and flexible testing environment for prototype systems connected to distribution networks with a specific focus on testing systems that control demand side resources for frequency response during loss of generation events.

Validation of Algorithms to Estimate Distribution Network Characteristics Using Power-Hardware-in-the-Loop Configuration

Distribution system operators (DSOs) require accurate knowledge of the status of the network in order to ensure the continuity and quality of power supply. In this context, the National Physical Laboratory (NPL) and the Power Network Demonstrations Centre (PNDC) have been working together in the development and validation of optimal sensor placement and network topology estimation algorithms. This paper presents the description of two of these algorithms as well as the topology configuration of the PNDC distribution network considered to gather measurements for the validation of the algorithms. A Power-Hardware-in-the-Loop (P-HiL) configuration has been used as the testbed, where a number of physical measurement devices are installed in the physical network and an extended number of devices are virtually installed in the simulate network. The applications of the proposed algorithms to the measurements along with results from the P-HiL tests are presented in the paper.

Smart integrated adaptive centralized controller for islanded microgrids under minimized load shedding

In this paper, a smart integrated adaptive centralized controller is proposed for monitoring and controlling integrated renewable energy sources (RESs), both for intentional and unintentional islanding modes of operation for microgrids, as well as, for a variable range of transient load shedding and fault scenarios corresponding to electrical power system outages. It is demonstrated that the proposed smart adaptive controller is capable of instructing fast frequency response by proper coordination of the dispatch of RESs units such as, mini-hydro, Photovoltaic (PV), Battery Energy Storage System (BESS) and standby diesel generators. In particular, the BESS used as power reserve, at the early stage of fault events can prevent detrimental and uncontrollable system frequency decline and the extent of load shedding. In summary, the performance of a centralized controller in terms of a fast frequency response recovery feature is validated for an actual microgrid distribution network of Malaysia. The demonstration of this intelligent control scheme highlights the advantage of utilizing the fast power recovery response of energy storage and standby generator, which fulfil the criteria for minimal load shedding from the main grid, during the unintentional microgrid islanding conditions.