Christophe Batard

Application of Power Line Communication for Data Transmission Over PWM Network

In industrial applications, a feedback loop is used in order to transmit control and diagnostic informations from the motor back to the inverter. The implementation of such feedback loop requires the use of extra cabling between both sides and that may have length exceeding few hundred meters. In this paper, the motor feeder cable is used for data transmission instead of the separated extra cable by using the power line communication (PLC) technology. However, beside the fact that feeder cables are not designed for data transmission, they are also polluted by the inverters outcome. Therefore, PLC modems developed for domestic applications may not be suitable. The aim of this study is to underline the possibility of communicating in such an environment. Limitations and difficulties that obstruct transmission are revealed. Also, possible solutions are discussed such as the use of a pulsewidth modulation filter in mean to overcome those limitations.

Lumped Dynamic Electrothermal Model of IGBT Module of Inverters

This paper presents a lumped dynamic electrothermal model of an insulated gate bipolar transistor module of inverters. The thermal model consists of a 3-D network of RC cells constructed for time-dependent operation. The network was found to be precise for determining the temperature excursion of diodes and transistors subsequent to time-dependent power losses. Thermal resistances and capacitances accounting for heat spreading and thermal penetration depth effects were introduced. Electrothermal simulations carried out on a 1200 V-300 A module with a time-dependent average power loss were found to be in good agreement with experiments using infrared thermal imaging. This paper focuses on very-low-frequency behavior (less than 1 Hz) at a switching frequency of 10 kHz.

Effect of the Power Cable on Data Transmission Over a Pulsewidth-Modulated Network

Power line communication (PLC) technology has proved itself in the last decade as an interesting solution for data transmission and communication in domestic application. Lately, this technology has been considered as a potential solution for monitoring and diagnosis of a motor-fed inverter setup. Information issued from sensors would be sent via power cables back to the controller despite the harsh environment and the switching of the inverter. This paper discusses the use of PLC technology over a pulsewidth modulation network by underlining the effect of the power cable length and the inverter switching on communication. A new approach based on the measurement of scattering parameters is used for this purpose, and the effect of the cable length is analyzed. It is shown that, for long distances, the PLC technology may not be effective, and hence, it is not possible to use power cables for communication.

A model reduction approach for constructing compact dynamic thermal models of IGBT-modules of inverters

This paper presents a model reduction approach for constructing lumped RC thermal networks of IGBT-modules of inverters for which heat and subsequent temperature increases vary with time on different scales ranging from nanosecond to second. It was observed that the time-dependent heat and temperature profiles of transistors and diodes of IGBT-modules of inverters oscillate at two frequencies, one in the range 0.1-50Hz corresponding to the load current modulation, and the other in the range 1-20kHz corresponding to the switching frequency. The reduction approach consisted of decomposing the module into different elements, each being described with a number of RC cells selected according to the time-constant of the element with regard to the module. The lumped RC thermal networks were found in good agreement with the continuous model by offering a considerably lower computational time on the different time scales. For simplicity, the reduction approach is presented for one-dimensional heat flow through the cross-plane direction of the module.

A PLC-Based Method for Data Transmission Over a Pulsewidth-Modulated Network

The use of power networks as a communication medium is currently under development. Power line communication (PLC) is a recent technology that allows interconnecting high-speed multimedia equipment while using the conventional domestic electric network. This paper deals with the use of this technology over pulsewidth-modulation (PWM) networks in motor-drive applications. The originality stands on the frontier of two distinct domains-communication and energy. First, the performance of the PLC technology conceived for domestic applications is evaluated when used over a PWM network. Operating limits and main difficulties encountered are underlined. Based on the requirements of the PWM network, new PLC modems are developed and tested. Experimental results presented in this paper show the capacity of these modems to overcome the hostile environment due to the inverter and to guarantee reliable communication over the PWM network.

Power Line Communication Management of Battery Energy Storage in a Small-Scale Autonomous Photovoltaic System

Today an increasing number of batteries are equipped with a digital battery management system (BMS) either for safety issues or lifetime improvement, or for both. In order to avoid the use of dedicated wiring for communicating with these BMS, a power line communication (PLC) solution is proposed to communicate through the dc power line inherent in these systems. This solution is also designed to be directly compatible with the existing controller area network controllers integrated in a large number of commercially available microcontrollers. It uses a single carrier generator in order to generate a shared carrier signal on the bus. Each modem can modulate this common carrier signal by switching the impedance it presents on the bus. In a first part, this paper proposes an overview of the industrial context of this PLC solution, including simulation results and discussion of the theoretical limits of the system. Then, the digitization stage interfacing the controller to the power line is described and a first prototype is validated through discussion of experimental results obtained within an actual industrial environment.

Development of a PLC modem for data transmission over a PWM power supply

In variable-speed electrical drive and online conditioning monitoring, a feedback loop is required in order to transmit the sensor information from the motor to the controller close to the inverter. Additional cabling is used for signalling. This extra cabling has a significant cost and data transmission may not be reliable. Thus, the use of power line communication (PLC) technology to transmit data in motor drive application is quite interesting. The use of a PLC modem dedicated to the home network in a three-phase inverter-fed motor power cable does not work. Therefore, specific coupling interfaces are developed to transmit data through a pulse-width modulated power supply. Laboratory tests have shown that the couplers are operating properly. They ensure reliable data transmission in a motor drive application.

Control of Shunt Active Power Filter for Railway Sub-station

This paper presents the results of a study for the connection of sub-stations of French railway traction at the 20 kV EDF distribution network. A solution containing active power filter is adopted. The main constraint is the filtering of the predominant harmonic current components of rank 11 and 13 which are absorbed by the traction group. First, it is necessary to determine the appropriate structure of the active power filter. Then, it is necessary to design passive elements and assure appropriate current regulation. At last, it is necessary to extract from the non-linear load current the harmonic components to be compensated. Two methods of selective harmonics identification are presented and analyzed. The simulations carried out with PSIM coupled with Matlab Simulink make it possible to validate the adopted solution

Modeling of a communication channel on a PWM electrical network

This paper deals with the transfer of data by Power-Line Communication (PLC) on a Pulse Width Modulated (PWM) energy network. Target applications concern the adjustable speed drive for industrial infrastructures. In order to implement an efficient communication solution, it is necessary to have a model of the communication channel to determine certain parameters like bandwidth, carrier frequency and modulation formats. The originality of our work is the methodology used to determine the channel model. The first results of simulation and experimental validation are presented in this paper.

Battery management through PLC-CAN communication

This article presents a new method allowing data exchanges between a Battery Management System (BMS) and the application’s Energy Management System (EMS). The proposed solution is based on the Power Line Communication (PLC) technology and harnesses the versatility of the well-known Controller Area Network (CAN) protocol. This new PLC-CAN communication system is depicted in the context of the management of a distributed battery pack composed of several batteries connected in a star topology. Limits of the system are exposed, arising from the trade-off between the carrier frequency and the length of the power cables. A theoretical approach through simulation is proposed and shows the feasibility of the PLC-CAN system. Measurements realized on an experimental setup confirm the validity of this new physical medium for the CAN protocol.