Electric vehicles (EV), smart cities, smart grid and smart factories – looking at the future it seems everything gets smarter and more environmentally friendly thanks to the intelligent application of electricity.
However with increasing demand for electric power we will face significant challenges as it will be difficult to satisfy our needs with renewable energies. There are many factors influencing the efficiency of electricity supply from power plant to our end devices and applications. The U.S. Energy Information Administration (EIA), estimates that some 6 percent of electricity generated in the U.S. is wasted in supply and disposition—more than 14 million megawatt hours annually in recent years.
Not all of the power losses along the way can be eliminated but one cause for energy waste can be reduced an thus help to decrease the overall amount of electricity we have to generate: power conversion.
Between the power generation and the actual power consumption there are usually several steps of power conversions. The reason is, that the transmission of higher voltages (usually in the range of ten thousands of volts) is by far more efficient than the transmission of lower voltages. However, as consumer applications require only a fraction of the transmission voltage (e.g. embedded processors often require only the fraction of a volt) and the safety concerns for high voltages are significant, power outlets usually deliver 110/120- and 220/240 volts.
For residential, commercial, industrial and automotive applications high voltages are those that range from just above the levels of electronic circuitry up to the levels of transportation and industrial equipments – that is, from tens of volts into hundreds.
In order to adapt to these different needs within the distribution path, it makes sense to transport the high voltages from the power plant as close to the consumer as possible before converting it. In addition, it is necessary to increase the efficiency of power conversions in general.
To address these needs and to make power generation, transmission and consumption more efficient semiconductor manufacturers like Texas Instruments (TI) invest tremendous effort in innovative power management and new high-voltage solutions.
In order to achieve higher IC performance, reduced size, maintained reliability and cost-efficiency we need to overcome challenges in the areas of manufacturing process, on-chip components, circuit design and also packaging.
The adoption of new solutions can further be accelerated through integrated, all-in-one solutions with in-depth hardware and software design support.
Compared to traditional power supply design, switched-mode power supplies (SMPSs) are way more efficient but also come with a little tradeoff as they represent complex designs. SMPSs create currents at high frequencies that must be prevented from propagating deep into the system and escaping back out into the source. Furthermore, operation of sensitive devices inside the power supply is susceptible to impedances from inside and interferences from surrounding components. For these reasons, SMPS solutions that integrate as much of the system as possible can help reduce the complexity of power supply designs and help lower manufacturing costs.
Innovations in this area are driven by research and development in the fields of process advances, integration, isolation, high-frequency programmable controllers and advanced packaging.
Advancements in manufacturing process technologies improve the voltage and frequency capabilities of silicon for use in power designs. Furthermore, new materials such as gallium nitride (GaN, built on a silicon substrate) and silicon carbide (SiC) can enable even faster switching and help to increase power density and to lower system cost.
TI has developed several gate drivers for GaN switches and is starting to introduce advanced multichip modules (MCMs) that include both gate drivers and GaN power switches.
Integration in form of single-chip solutions that integrate as many power supply components as are practical is viable in order to rescale high-voltage power supplies to fit on a board inside the end equipment and to find a balance between cost and performance.
Single-chip and MCM solutions increase the complexity of isolation as the traditionally used transformers, which sit as bulky components outside the integrated circuits, are not suitable. However, new methods of isolation are in development that will serve to eliminate external transformers and isolate the system from within the chip or MCM.
As slight variances in timing could quickly magnify into big variances that diminish the efficiency of the system it is crucial to complement gate drivers and power switches with precise control. At a minimum, the high frequencies of new SMPS designs call for digital control from high-performance state machines. Innovative software tools help power designers to understand how to develop the closed-loop control functions of a digitally controlled SMPS system using e.g. a TI C2000 MCU or UCD3138 digital controller, simplifying the transition from traditional analog control methods.
Last but not least innovative power solutions require sophisticated single-chip and MCM packaging that can handle requirements for electrical integrity and thermal stress created by high-voltage operation. Common concerns within packaging solutions are types of materials, bonding techniques and methods of protection against degradation.
The innovations addressed above will play a vital role in several industrial sectors in our future. ICs and new power semiconductors will enable power conversion with minimal power losses which will benefit power grids, factories, homes, cars and other systems. In addition connectivity will help systems to communicate and to control system power usage efficiently.
Texas Instruments and EBV are working on innovations that will help to save more energy in the future and to increase efficiency in power management. Read TI’s Whitepaper “Redefining power management through high-voltage innovation” here and checkout EBV’s Renewable-Energies website here for more information.