Semiconductor makers Microsemi and STMicroelectronics have combined their silicon to create a new module for vehicle-to-grid (V2G) communication. The module for electric vehicle supply equipment (MEVSE) will be the first of many IoT focused collaborations from the two companies, and supports network and application protocols from Tatung – a Taiwanese OEM and ODM.
The module combines the Microsemi Le87501 PLC line driver with STMicro’s ST2100 STreamPlug SoC, along with a new proprietary digital power controller that runs the OpenV2G software stack – an open source project to support the ISO and IEC standardization process for V2G communication interfaces. OpenV2G provides a reference implementation of the communication that takes place between MEVSE vehicle chargers and plug-in hybrid electric vehicles (PHEV) – as defined by the DIN 70121 standard.
Microsemi’s Le87501 PLC line driver is based on patented high-speed, high-voltage bipolar process. A line driver is used to amplify an analog or digital signal that is sent along a wire. In this case, the line driver is needed to ensure that a communication sent along the power wiring from one end of the house to the other reaches its destination intact and legible.
The Le87501 is a single line driver that is HomePlug AV2 compatible, which can drive a line impedance of 100ohms down to 12ohms through a transformer. It measures 4mmx4mm and includes a long-term sleep mode to save power when not in operation.
The STreamPlug SoC bills itself as the first intelligent gateway SoC. The ST2100 chip combines processing power with power line communication capability, to support HomePlug AV (Audio Visual) and HomePlug Green. This enables gateways using the ST2100 to connect the power line communication that will likely be used by charging electric vehicles as well as by the connected energy meters in the home – allowing the utility data to be shared with the home hub at the center of a smart home.
The chip uses an ARM926EJ-S processor, which operates at frequencies up to 333MHz. STMicro notes that this processor is widely used in applications where high computational performance is needed, such as consumer home area networking, industrial and smart grid communications. A memory management unit that provides virtual memory management, which makes the SoC Linux compatible. It has 16KB of data cache, with 32KB of instruction cache.
“Microsemi’s high-performance line drivers, along with the STreamPlug SoC, provide a world-class IoT total solution, enabling faster development of innovative power management systems,” said Shahin Sadeghi, the director of marketing at Microsemi.
In both Toyota’s and Honda’s smart home reference designs, a Home Energy Management System (HEMS) forms a central part of the smart home. Both use a large storage battery and a rooftop array of solar panels to generate and store electricity, which is then used to power the appliances in the home. Efficient insulation and construction techniques help reduce the power consumption of the home, which in turn helps it draw less power from the main grid – relying on its own solar panels to do much of the work.
When villages or towns of these houses are built, they form smart grids, also known as microgrids, which help to distribute the total power generation efficiently between the households. This also allows the power supply to be more resilient in the face of outages, given that the power generation is now distributed at both a national and local level.
But systems like this require coordination, and that is where the technology such as the new MEVSE module comes in – as the different elements of a smart home need to be able to talk to each other.
The two companies are also working together on audio sensing and voice-centric command and control systems. Combining Microsemi’s Timberwolf audio processors, which are built to provide clear speech to a digital signal processor (DSP), free of signal noise and echo.