Power Line Communications Receivers Research Articles

A novel fault monitoring method based on impedance estimation of power line communication equipment

Due to the close relationship between power grid fault and impedance, there is a significant defect in the use of power line communication (PLC) equipment to monitor and locate power grid faults, which is the lack of real-time impedance information. Therefore, this study proposes a new fault monitoring method based on impedance estimation of power line communication equipment. The channel frequency response (CFR) obtained from the PLC receiver is used to estimate the high-frequency input impedance to monitor and locate the ground fault of the power grid in real time. Firstly, based on the multi-conductor transmission line theory, bottom-up channel modeling method and impedance estimation technology, the basic principles of fault monitoring and location methods are clarified. Then, modeling and analysis of cables in different situations are carried out, and the characteristics of the factors affecting the impedance in CFR are extracted by variational modal decomposition (VMD), and the estimation results of impedance are obtained by inversion analysis. Based on this, the impedance change and machine learning algorithm are used to track and identify the abnormal state of the power line to achieve high-sensitivity positioning of the cable fault. The simulation results show that the method has a good identification effect on high and low impedance cable fault, and has a better effect on low resistance fault monitoring. The fault location error is less than 2.13%, and has a good positioning accuracy.

Physical Layer Security of In-Home PLC Systems: Analysis Based on a Measurement Campaign

This article investigates the physical layer security (PLS) of a broadband in-home power line communication (PLC) system when a malicious and passive PLC device tries to eavesdrop upon private information sent by a PLC transmitter to a legitimate PLC receiver. In this setting, the ergodic achievable secrecy rate, secrecy outage probability, effective secrecy throughput, and wiretap code rates are numerically evaluated with the use of a data set obtained from a measurement campaign carried out in several Brazilian houses. This data set comprises PLC channel estimates and measured additive noises considering four distinct sets of transmitter, legitimate receiver, and eavesdropper positions. Numerical results, covering three distinct frequency bands (1.7–30 MHz, 1.7–50 MHz, and 1.7–86 MHz), quantitatively show, in practice, the level of vulnerability of broadband in-home PLC systems in terms of PLS and offer some directions for an appropriate design of PLC modems to improve PLS.

Robust multipath channel estimation in the presence of impulsive noise

Power-line communications (PLCs) endure a severe transmission channel distortion due to Gaussian noise, impulsive noise, and multipath self-interference. Conventional transmission models with white Gaussian noise would be very inappropriate and impair the necessary channel estimation drastically to the PLC receivers. In this study, a statistical model for impulsive noise, namely Middleton Class A model, is employed for Gaussian information sources. Robust channel estimation algorithms based on a novel parameter estimation scheme are established thereby. Superior to the conventional robust-least-square estimation algorithms, the authors' proposed new adaptive robust-least-square estimation methods can take advantage of the statistical parameter estimation for impulsive noise. The studies on the theoretical and practical aspects of their proposed new parameter estimator are also presented.

Power Line Carrier Communication Using Automated Meter Reading

A new concept of Power line Communication. Now human operators do the Meter reading for the consumption of Electricity from house to house and building to building. It requires huge number of labor and takes more time to complete the process. Reading error is a common cause of human operator. Automatic Meter Reading (AMR) becomes an executable option to overcome the problems of huge time taking to get the meter readings, the measured values are in kilo watt-hours (kWh) by energy meter. The supply status of the consumer reading unit we identified the disk rotation of the energy meter. The main advantage of this system is a low cost system that produces very encouraging results and it can be implemented upon existing electro-mechanical meters so there is no need to purchasing new meters AMR is the remote collection of consumption data from customer’s utility meters over power line. Power-Line Communication (PLC) carries data on a conductor that is also used simultaneously for AC electric power distribution to consumers. PLC transmitter is responsible for transmission of data from the provider end. At the provider end, there will be the PLC receiver, which is responsible for data receiving, and this module makes an interface with computer, which is responsible for data processing.

Immunity of Automotive Power Line Communication Systems

Power line communication (PLC) could not be established in automotive environments till now due to concerns with the unavoidable electromagnetic disturbances in the vehicle supply nets. Conducted broad band switching noise and field coupled narrow band noise can disturb the communication and prevent higher data rates. The continuously increasing size of the communication cable harnesses in vehicles is very difficult to handle, and PLC could reduce the complexity of the harness. This paper presents an approach to estimate the theoretical limits of PLC in the presence of noise in automobiles. Signal power and bit error rates are computed and discussed, based on electromagnetic compatibility-standards and PLC-parameter sets from older investigations’ noise levels. Commonly used automotive immunity tests are applied to analyze the signal to noise ratio of the PLC in a simulation environment. Therefore, immunity test setup models are introduced in order to analyze the noise injection and coupling characteristics to the PLC receiver. A virtual direct power injection (DPI) test is carried out with narrow band noise and transient pulse injection. For method validation, BCI measurements of a real PLC transceiver were carried out and failure behavior was compared to DPI simulation results. Immunity improvement for single carrier modulation in PLC is proposed. Finally, an analysis of the immunity to pulses is performed and results are discussed.

Mitigation of Periodic Impulsive Noise in OFDM-Based Power-Line Communications

This paper presents a novel approach to mitigate the periodic impulsive noise before the synchronization of the orthogonal frequency-division multiplexing (OFDM)-based power-line communications (PLC) system. The proposed algorithm is employed to detect the periodic impulsive noise and then suppresses the periodic impulsive noise with an adaptive infinite impulse response (IIR) notch filter before the synchronization of the system, finally compensating the distortion of received signals brought by the IIR notch filter. Subsequently, the periodic impulsive noise mitigation algorithm is simulated and implemented in the PLC receiver's physical layer. Finally, the proposed algorithm is verified in field-programmable gate array and tested in the indoor PLC network. The simulation and field trial results show that the proposed periodic impulsive noise mitigation technique is simple and effective for the narrowband OFDM-based PLC system, such as the application of automatic meter reading.

Method to Cancel Impulsive Noise From Power-Line Communication Systems by Processing the Information in the Idle Carriers

The standards which rule power-line communications (PLC) systems specify that power must not be transmitted in those carriers, corresponding to the frequency bands of several radio services, such as amateur radio or radio broadcasting, in order not to interfere with them. So at PLC receivers, only a little power from background noise and perhaps some interference would be found in those idle carriers. When impulsive noise (IN) enters a PLC receiver, its energy spreads throughout the entire receiver band. The IN introduced in the idle carriers is very high compared to their background noise; therefore, we propose a method to cancel IN by using the information received in these idle carriers.

Cancelling Wideband Impulsive Noise by Processing the Masked Tones in Power Line Communications

It has been demonstrated that Power Line Communications (PLC) can interfere with some radio services. In order to avoid it, PLC standards specify not to transmit at the same frequencies where these radio services operate. These frequencies are called the masked tones. As they carry no transmitted power, the masked tones can be used to detect and cancel impulsive noise (IN), which most of times is wideband and leaks out into the whole PLC band. This research work presents a new procedure to identify and eliminate IN from PLC receivers, being able to recover the original signal samples which have been impaired by the IN pulses.

Modeling and Analysis of Noise Effects on Broadband Power-Line Communications

Power line noise is known to affect the performance of broadband power-line communications significantly. This paper presents a frequency-domain approach to characterize and model the statistical variation of power-line noise. The model considers both the background noise and the impulsive noise. The background noise model is based on statistical analysis of the results from two long-term measurements of noise spectrum conducted at two separate sites of a laboratory and a residential apartment. On the other hand, the impulsive noise model is obtained by direct measurements from the noise sources (i.e., various electrical household appliances). The amount of impulse noise reaching a power-line communications (PLC) receiver can then be determined with consideration of the channel transfer characteristics between the noise sources and the PLC receiver. Using these noise models, the performance of two major classes of digital modulation schemes, namely single-carrier modulation and multicarrier modulation, are analyzed and compared. It is found that the multicarrier scheme performs better than the single-carrier scheme when subjected to the observed power-line noise with non-Gaussian statistics.