This document discusses the importance of improving the efficiency of switch mode power supplies (SMPS) used in telecommunications and industrial equipment. SMPS are crucial as they efficiently convert incoming power sources like AC grids or batteries into regulated DC power needed to operate electronic circuit boards. With growing technological demand, improving SMPS efficiency by even 1% can result in significant cost savings for operators with large networks. The document also mentions new technologies like gallium nitride that promise further efficiency gains for SMPS. Overall, optimizing SMPS efficiency across all loads is seen as an important requirement given rising energy costs and environmental concerns.

1. 56 • PowerWatch INDIA • January 2016
TECH & SERVICES
ENERGY EFFICIENCY
By Srivatsa Raghunath and Francesco Di Domenico
There is a huge increase in the need for telecom
base stations and industrial automation. At the
backend of each technology related equipment
is an electronic circuit board powered by a power
supply, called Switch Mode Power Supply (SMPS).
The goal of SMPS is to efficiently convert available
input power to DC output power as required by
the electronic circuit board. Input power can be
available from power grid or diesel generator sets
as alternating current, from batteries or solar panels
as direct current (DC). Output DC power need
varies from chargers (20W) to LCD
TVs (200W) to telecom rectifiers
(2000W). Outburst in technological
growth demands a large number
of equipment to be connected
to a limited input source. Hence
“efficiency” of converting input
power to output power becomes
crucial in selecting SMPS.
Large scale telecom operators
and industries can save costs by
becoming more energy efficient.
Reducing energy consumption by
improving efficiency is a challenge
due to the absence of regulations or
stringent specifications as present
in the IT industry.
In India, there are 850k telecom base stations in
about 650k telecom towers with an average power
requirement of 2kW per base station to be available
24x7. Due to unstable grid conditions, there is heavy
dependence on non-renewable energy sources such as
diesel, which further add to the operating costs. Few
companies have realised this and are using renewable
energy sources such as solar or wind power, mainly
in rural areas. But urban areas are still largely grid
powered. Imagine improving efficiency by a mere 1%
in a 2kW SMPS, which translates to savings around
20W per SMPS which in turn saves around 2000kW
for 100k base stations. Multiply this with the hourly
demand and you´ll arrive at a mind boggling number
in the amount of cost saved by just improving SMPS
efficiency by 1%.
An important component affecting Total Cost
of Ownership (TCO) is reliability of components,
repairs can be costly in labour and reserve-capacity
provisioning. A similar but maybe less tangible
element affecting TCO is serviceability of equipment,
which involves time, and therefore cost of repairs
and upgrades. Size and weight of components,
especially SMPS, significantly influence this
parameter. Hence the trend in increasing efficiency
increases power density. An important contribution
to future efficiency and power density is expected
to come mostly from system architecture and power
management optimisation. Hence, digital power
management techniques are now used across power
supply manufacturers.
The role played by semiconductor companies like
Infineon in SMPS advancement is a crucial and clear
one: power devices, driver ICs and digital controllers,
everything inside our portfolio, are all fundamental
parts of SMPS. Our company has working demo
boards to evaluate SMPS performance. There are
600W to 3200W designs available with digital
control implementation. In applications with low
output voltage, further efficiency improvements
have been made possible by continuous reduction
of on-resistance of low-voltage MOSFETs, like our
OptiMOSTM
series, used as synchronous rectifiers. The
introduction of innovative devices based on Gallium
Nitride (GaN) material promises further revolutionary
advancements in SMPS.
In conclusion, growing telecom and industrial
infrastructure markets along with the rising cost of
energy and environmental concerns makes SMPS
efficiency optimisation across the entire load range a
key requirement.
Suality engineeringSMPS: A crucial component
The authors are Application
Engineers, AC-DC at
Infineon Technologies AG.
Power Supply Unit
Power Distribution Unit
Battery Protection Unit
Battery
Fans / Ventilator
Digital Unit
Radio Unit
Fans / Ventilator
Telecom Rectifiers 800 W to 2500 W AC-DC Converters
MPPT based Solar Charge Controllers
Telecom Tower
AC GridWind
Diesel Generator
Solar Panel
170 VDC
to 230 VDC
Input
230 VAC
to 400 VAC
Input
Telecom rectifier