Monday, September 21, 2015

Power Line Communication (PLC) applied to EV or EV Charger in yet installed electric systems in emplacements with no wireless cover

The Electric Vehicle (EV) implementation will have severe consequences in the Electric Systems and its operation, in the Automotive Industry, and of course in the society.
Furthermore, the EV will have severe change in the behavior of the vehicle users comparing with the actual situation with “conventional cars.”

Nowadays, the level of the battery in the Smart Phones, it is taking the most important investments and concerns for the Smart Phones Industry.
In the future, the level of the batteries, or the technology applied. It will be the most important concern for the EV users.
The Automotive Industry is taking the Smart Phones, such as the most common tool to inform to the EV user (outside the EV) about the level of batteries, in terms of electricity to move the vehicle.

This important concern, will have great repercussions to establish the properly communication between the Smart Phone of the EV user, and the EV, or failing, with the EV Charger.

PLC will be able to solve the issue when the EV is in whatever emplacement with no wireless cover, even more, knowing that for the EV fulfillment and its Charging Stations will must use the yet implemented electric systems. This represents great consequences in terms of cost, for the cost of the new installation (cable, protection systems, etc.). And on the other hand, for the cost, if the electric consumption is higher. Not only in terms of electric bill, also in terms of increasing the contractual scale with the provider.


Figure 1_ PLC is also being developed in aeronautics, just to reduce among of cable, using the power cables to transmit data.
In the picture, example of cable harness in an aircraft. In the left, the cable harness in an engine pylon structure in Aeroscopia Museum Toulousse. 
On the right, an example of cable in the fuselage of an aircraft in Aeroscopia Museum._Source: J. Sánchez Ríos.


PLC is used in Automotive Industry to communicate the electronic devices and control units in the vehicle. Mostly, for avoiding cables in the wire harness of the Vehicle, using basically different protocols; FlexRay, LIN (Local Interconnection Network) and CAN bus (Controller Area Network). CAN Bus, even is implemented in a lot of applications for its high reliability in industrial environments.


Figure 2_ Example of sectioned Car 5 Series BMW in the front side in Berlin Teknikmuseum._Source: J. Sánchez Ríos.


The EV implementation opens a good chance to the Automotive Industry. The challenge is not only regarding the EV. The automotive industry will must support to all regarding the EV and its charging systems. Likewise, it is also important to mention the consequences to the Electric System with the high demand of power to supply this EV implementation.
Similarly, this chance, it will bring an effort in the implementation of communication technologies, not only for Vehich to Vehicle (V2V) or Vehicle to Infrastructure (V2I) technology. Furthermore, the customer needs to be informed about the level of EV battery, State of Charge (SOC), or the EV Charger availability in the respective Smart Phone (independently of the emplacement of the EV or the EV Charger, in terms of wireless or non wireless cover of the EV or EV Charger emplacement).

Figure 3_ Nissan Leaf charging with a Smart Phone App view (bottom-right corner), which shows the State or Charge (SOC) for the battery system (Smart City World Congress in Barcelona)._Source: a) Picture of the Nissan Leaf charging: J. Sánchez Ríos // b) Picture of the view of the SOC App: Cellphonebeat.


Getting in deep with the last point. If the EV charging system is installed in a new building, for sure, in the engineering design, it has been implemented the Internet communication, mostly by cable (coaxial, fiber optic, etc.), or by wireless communication. As a result, there is no issue for communicating the EV or the EV Charging System with the Smart Phone of the EV owner.

Conversely, considering the particular case of an emplacement of the EV or the EV Charging Station with no wireless (most of the underground parking), the availability to establish a communication between the EV or the EV Charger with the Smart Phone of the user is very complicated (if the user is emplacement not in the same emplacement of the EV).

It should be noted the complication, in terms of cost, to implement a new communication system from the EV or from the EV Charger to the Smart Phone in the underground parking, just for being the parking in a non wireless cover emplacement.

For getting a solution in the issue exposed. The communication from the EV or the EV Charger to the wireless communication cover emplacement will be made in two steps and by two communication technologies.
PLC will communicate the EV or the EV Charger from the non wireless cover floor (normally underground), to the first floor where wireless cover is available.
After that, when the signal is arriving to first floor of wireless cover, just by using one router, for codifying the signal from PLC to wireless communication. The system can transmit the information using whatever wireless communication for being connected to whatever Smart Phone.

If it is taken in consideration the most common example, with EV charger mode 1 (250 V
monophasic or 480 V triphasic AC power) in an underground parking (no wireless cover). PLC (Smart Grid PLC) will communicate between the on-board to off-board vehicle systems, following IEC 61851-1. Connecting the EV Charger to the respective battery control units inside the car; BMS (Battery Management System) and EMS (Energy Management System). All of that, using a connection of the Smart Grid PLC and the the PLC protocols used by Automotive Industry; LIN, CAN-C, CAN-B or FlexRay bus, just to establish a communication between the control system inside the car (on-board) and the Smart Grid PLC in the off-board in the EV and in the EV charging System. 
After finishing the communication between the EV and the EV Charger System. It is necessary to establish the communication from EV Charger to the next electrical point on the ground (normally higher floor). This operation, is made by Smart Grid PLC, after that, the communication is transmitted from the PLC technology to wireless technology by a router, to find a wireless ISP (Internet Service Provider), and then arriving to the Smart Phone.
In terms of PLC functionality, and as it is shown in the figure 4, BSS, is the basic element to
consider in PLC network and its management with BM. PLC routers are depending of users
connected to Low Voltage (LV) electric system.




Figure 4_ Example of electric and communication system by PLC in the interconnection of the EV and the Smart Grid._source: J. Sánchez Ríos


As a conclusion, PLC will have great consequences in the implementation of EV Charger in the existing buildings.
Of course, for the Automotive Industry will be a great challenge. Because the customer will want to know the state of the EV Batteries (SOC), despite the EV or the EV Charger emplacement: indoor or outdoor parking, with wireless or not cover. And for getting this "Service," the Automotive Industry will need to implement new technological solutions. 

Similarly, in Smart Homes applications, for controlling Home Appliances, and even to insert in the control boards remotely.
In Smart Cities, to control in the yet installed electric infrastructure.
In avionics industry, just to reduce the among of cable in the aircraft and reduce weight.

Finally, it is important to remark the solution implemented in this article and the great consequences for the Transmission System Operator (TSO). Just to know the EV Chargers consumption state. The relevance to control the Vehicle to Grid (V2G) Chargers and the level of battery in the EV, in case of emergency, to use this electricity to supply the critical infrastructure.

Index Terms:
IEEE 1901.1, Electric Vehicle Charger (EVC), Electric Vehicle (EV), IEC 61850, CAN Bus, LIN, Power Line Communication (PLC), Power Line Carrier, Smart Grid, Smart Home, Smart Building, Smart City, Electric Systems, Automotive Industry, wireless communication, batteries, storage systems, Charging Stations.


REFERENCES

  1. IEEE 1901.1 - IEEE Standard for Broadband over Power Line Networks: Medium Access Control and Physical Layer Specifications.
  1. Power Line Communication for Smart Grid, Smart Cars, and Smart Homes - Krzysztof Iniewsky and Tracey Mozel.
  1. El Vehículo Eléctrico - Desafíos tecnológicos, infraestructuras y oportunidades de negocio STA: Sociedad de Técnicos de Automoción – Librooks.
  1. Eficiencia en el uso de la Energía Eléctrica – Circutor

J. Sánchez Ríos
javier.sanchezrios.1978@ieee.org