Power Quality Monitoring Device Research Articles

Implementation of an IEC 61850-Based Metering Device Using Open-Source Software

The continued adoption of renewable energy and distributed generators has resulted in a rising number of supply points within the traditional electric power grid, necessitating the need for enhanced monitoring capabilities. The IEC 61850 standard can become an enabling technology for enhanced monitoring, but prohibitively high costs and complexity of compliant devices could become an impediment. Open-source IEC 61850 libraries, coupled with single-board computers and digital signal processors, provide a possible low-cost solution. This work presents the process of modelling and implementing such a device using an IEC 61850 open-source library, a Raspberry Pi embedded platform and an ADE9000 analogue front-end. Measurement accuracy and interoperability compliance tests are conducted to determine the suitability of the device for use in an industrial setting. A key contribution of the findings in this paper is the modelling and implementation of a viable, interoperable and low-cost IEC 61850-based power quality monitoring device using off-the-shelf components and an open-source software library. The implementation of this device provides a platform that is easily modifiable for use in a range of applications. Another contribution is the method of modelling IEC 61850 logical nodes and functions to analogue front-end measurement registers. The knowledge demonstrated shows how device modelling techniques can be used to extract additional information for mapping to existing logical nodes or to develop new ones. The paper's findings result in a low-cost IEC 61850-based power quality monitoring device. The device has applications as a general utility-scale monitor for DER plants, check metering, IEC 61850-based power quality mitigation algorithms and short-term power quality studies. It may also function as a low-cost entry point to IEC 61850-based communications in smaller municipalities, and additionally as a lab test and prototyping tool for technicians, engineers and university students.

A Generalized Approach for Power Quality Disturbances Recognition Based on Kalman Filter

This paper presents a new automatic detection and classification approach of power quality (PQ) problems using Kalman filter. Kalman filter is used as an estimator to calculate the fundamental frequency and harmonic components amplitudes of the voltage or current signals. Then the instantaneous total harmonic distortion (iTHD) and the energy are calculated. For each half cycle of the processed signal, five decision quantities are calculated based on iTHD and energy and these quantities are the three consecutive maximum values of iTHD, standard deviation and energy difference between distorted signal and its fundamental frequency component. Decision rules based on these decision quantities are applied to identify and classify the PQ events in this captured signal. The proposed approach is tested on single and combined PQ events that are generated using the MATLAB with the help of mathematical models that are conformity with standard IEEE-1159. The performance is assessed using more than 100 dataset of every PQ event and the results show that the accuracy is 100 and 98.8 for noiseless and high-level of noise, respectively. In addition, the proposed approach performance is validated through comparisons with other classification. Several practical PQ events are generated by lab experiments to validate the proposed approach. The simulation and experimental results show that the proposed approach is efficient and robust and can be implemented to design PQ monitoring device.

Advanced Distribution Measurement Technologies and Data Applications for Smart Grids: A Review

The integration of advanced measuring technologies in distribution systems allows distribution system operators to have better observability of dynamic and transient events. In this work, the applications of distribution grid measurement technologies are explored in detail. The main contributions of this review are: (a) a comparison of eight advanced measurement devices for distribution networks, based on their technical characteristics, including reporting periods, measuring data, precision, and sample rate; (b) a review of the most recent applications of micro-Phasor Measurement Units, Smart Meters, and Power Quality Monitoring devices used in distribution systems, considering different novel methods applied for data analysis; and (c) an input-output table that relates measured quantities from micro-Phasor Measurement Units and Smart Meters needed for each specific application found in this extensive review. This paper aims to serve as an important guide for researches and engineers studying smart grids.

A Hybrid Algorithm for Recognition of Power Quality Disturbances

An algorithm making use of hybrid features of Hilbert transform (HT) and Stockwell transform (ST) to identify the single-stage and multiple (multi-stage) power quality disturbances (PQDs) is introduced in this manuscript. A power quality index (PI) and time location index (TLI), based on the features computed from the voltage signal by the use of HT and ST are proposed for recognition of the PQDs. Four features extracted from the PI and TLI are considered for classification of the PQDs achieved using decision tree driven by rules. The algorithm is tested on the PQDs generated with the help of mathematical models (in conformity with standard IEEE-1159). Performance is evaluated on 100 data set of every disturbance computed by varying various parameters, and efficiency is found to be greater than 99%. It is established that an algorithm is effective for recognition of PQ events with an efficiency greater than 98% even in the presence of high-level noise. Algorithm is faster compared to many reported techniques and scalable for application to voltages of all range. Results are validated through comparison with the results of the algorithms reported in the literature. Performance of the algorithm is effectively validated on the practical utility network. This algorithm can be effectively implemented for designing the power quality (PQ) monitoring devices for the utility grids.

Recognition of Complex Power Quality Disturbances Using S-Transform Based Ruled Decision Tree

Deteriorated quality of power leads to problems, such as equipment failure, automatic device resets, data errors, failure of circuit boards, loss of memory, power supply issues, uninterrupted power supply (UPS) systems generate alarm, corruption of software, and heating of wires in distribution network. These problems become more severe when complex (multiple) power quality (PQ) disturbances appear. Hence, this manuscript introduces an algorithm for identification of the complex nature PQ events in which it is supported by Stockwell’s transform (ST) and decision tree (DT) using rules. PQ events with complex nature are generated in view of IEEE-1159 standard. Eighteen different types of complex PQ issues are considered and studied which include second, third, and fourth order disturbances. These are obtained by combining the single stage PQ events such as sag & swell in voltage, momentary interruption (MI), spike, flicker, harmonics, notch, impulsive transient (IT), and oscillatory transient (OT). The ST supported frequency contour and proposed plots such as amplitude, summing absolute values, phase and frequency-amplitude obtained by multi-resolution analysis (MRA) of signals are used to identify the complex PQ events. The statistical features such as sum factor, Skewness, amplitude factor, and Kurtosis extracted from these plots are utilized to classify the complex PQ events using rule-based DT. This is established that proposed approach effectively identifies a number of complex nature PQ events with accuracy above 98%. Performance of the proposed method is tested successfully even with noise level of 20 dB signal to noise ratio (SNR). Effectiveness of the proposed algorithm is established by comparing it with the methods reported in literature such as fuzzy c-means clustering (FCM) & adaptive particle swarm optimization (APSO), Wavelet transform (WT) & neural network (NN), spline WT & ST, ST & NN, and ST & fuzzy expert system (FES). Results of simulations are validated by comparing them with real time results computed by Real Time Digital Simulator (RTDS). Different stages for design of complex PQ monitoring device using the proposed approach are also described. It is verified that the proposed approach can effectively be employed for design of the online complex PQ monitoring devices.

A low power fuzzy logic based variable resolution ADC for wireless ECG monitoring systems

Portable low power and high quality monitoring devices play an important role for improving the performance of wireless body sensor networks. Mixed signal processor is required in ECG monitoring unit that comprises of analog front end, analog to digital converter (ADC) and digital signal processor. ADC is a core element in mixed signal processing unit and the proper design of ADC is crucial for data acquisition without losing heart related information and originality. The adaptive sampling has been used in the existing ADCs for choosing the sampling clock adaptively. Adaptive sampling rate ADC performs compression and reduces power consumption to some extent, however low powers ADCs are essential in wireless healthcare monitoring systems. In this paper, fuzzy logic based variable resolution controller is proposed to design the ADC efficiently in terms of circuit complexity and power. To further reduce the power consumption, power gating technique is adopted for static power reduction. Under 90 nm CMOS technology, gate count, core area utilization and power consumption have been determined for existing adaptive sampling ADC and fuzzy logic based adaptive sampling ADC. Cadence design tools have been used for the measurement of power in the designed circuit. The performance has been found to be better in terms of area and power that are very much essential for wireless ECG monitoring systems.

Design of a Distribution Network Power Quality Monitoring System based on Metering Automation Systems and its Application

According to the situation that almost all the power quality systems (PQM) focus on the transmission network rather than the distribution network (DN), a distribution network power quality monitoring system (DNPQMS) based on metering automation systems is proposed in this paper. This DNPQMS can take full advantage of the power data collected by the existing intelligent terminals that set throughout the DN. The DNPQMS is divided into three parts, including equipment layer, data layer and application layer. The equipment layer consists of power quality monitoring devices, including the power quality monitoring device based on dual-CPU platform and intelligent terminals of other manufacturers. The data layer completes the power data storage and integrated that collected by the intelligent terminals. The application layer completes the day-to-day maintenance and management of the system as well as a number of advanced applications. The verification of the DNPQMS by application is presented at the end of the paper. DOI: http://dx.doi.org/10.11591/telkomnika.v10i7.1450 Full Text: PDF

含风电场的电网电能质量评估及监测装置整定方法

为保证风电场接入电网后系统的电能质量满足要求，需要对其进行电能质量评估和测试；同时在并网接入点装设电能质量监测装置。文中首先提出了对风电场电能质量监测装置进行整定所需的数据，进而针对某一实际风场，根据电能质量国标中的规定及计算方法对其接入点装设的监测装置各监测量进行整定，包括电压偏差和谐波等；并通过建模仿真额定运行及风速扰动下的电能质量情况，与整定值进行比较分析。结果表明，风速扰动下的风场电能质量若不能完全满足要求，则需进行相应的改善。 It is necessary to evaluate and test the power quality (PQ) of wind farm to safeguard it to meet the PQ re- quirements after its access to grid, so that PQ monitoring device is installed in the grid access point. The data required for the setting of PQ monitoring device is listed first, then an example of the setting method of monitoring parameters of PQ monitoring devices is provided based on the provision and calculation method in National Standards, including voltage deviation and harmonics, etc. Through simulation and analysis, results are compared with the setting values. Finally, if the PQ of wind farm can not satisfy the requirements when wind speed disturbance happens, then PQ im- provements should be taken.

DSP in Power Quality Monitoring Device

The system of monitoring of power quality is introduced. The system contains three layers. The first layer works in real time and uses a fixed-point DSP digital signal processor. The second layer computer dimmPC reads data from DSP processor.The paper deals with hardware and functionality of the system. Division of power quality indices calculation between the system layers is also presented. Algorithms of data processing as well as ways of improving processing accuracy of signal processor are analyzed.