Energy-efficient switching power supplies core of development work

	Hangzhou Yukingda's FBK32-72W model integrates an EMI filter and short-circuit, overvoltage, -current and -temperature protection.

Suppliers incorporate power-saving features and improve specifications to meet requirements in industrial applications.

Manufacturers of switching power supplies in China are channeling R&D efforts toward high-performance yet environment-friendly units. Makers are improving power factor and standby and sleep modes to extend the operating life. Some enterprises such as Hangzhou Yukingda Imp. & Exp. Co. Ltd are developing models that can derive power from solar energy.

Kuantech (Shenzhen) Co. Ltd’s initiatives, meanwhile, revolve around boosting durability and Pf values.

Miniaturization is gaining traction to match trends in computers, LED lamp drivers, communication devices and consumer electronics products. Besides their compact designs, the latest releases pack anti-EMI, elevated efficiency and frequency, and low noise. To achieve the last, enterprises are adopting resonant converter circuit technology.

Manufacturers employ zero-voltage turn-on and zero-current turn-off technologies to increase frequency. Boosting reliability, meanwhile, involves reducing operation current and junction temperature.

Companies also use modular power supply and develop a distributed power system, which can be designed as N+1 redundant power system, to expand parallel capacity.

There are more than 4,000 makers of SPS in China, 400 of which are large operations. Thirty percent of the manufacturing pool is based in Zhejiang and Jiangsu provinces and Shanghai. Other enterprises are located in Guangdong province, Beijing and Tianjin.

The country represents less than 9 percent of the global switching power supply market, according to the China Information Industry Net. Exports, however, are projected to gather steam in future, thanks to strong demand from the computer and telecom sectors. Orders from the first were valued at $787.5 million in 2011.

Office automation and PCs account for 49 percent of the line, and telecom equipment 35 percent.

In 2010, output value reached $1.9 billion and the figure is forecast to climb by 20 percent in the next five years.

China makers are optimistic of better sales in coming months. Many project exports will increase by 20 percent amid strong demand from the semiconductor, automotive and consumer electronics sectors. In anticipation of an influx of orders, Kuantech has increased daily capacity from 200,000 to 350,000 units. The company has likewise forged partnerships with upstream suppliers to meet requests.

Hangzhou Yukingda is exploring emerging destinations to offset a potential downside in traditional markets US and Europe.

Switching power supplies from China are available in DC-DC, AC-DC and DC-AC types based on input and output waveforms. The first two dominate production in the country.

Manufacturers also offer DIN rail, brick and half-brick, open-frame and enclosed kinds. Further, buyers will find LED power, modular, DC-DC converters and AC/DC adapters.

Enclosed variants typically have one to four output ranging from 15 to 3,000W. DIN rail versions, are mainly adopted in industrial control equipment.

These provide 10 to 96W power output and 0.75W no-load power consumption.

LED switching power supplies used in display, backlight and illumination products deliver 16 to 300W power output and have metal or plastic housing. DC-DC converters are available in bridge, half-bridge and open-frame versions. The power output of the first is usually below 400W, while it is 50, 75 100 to 150W for half-bridge models.

For AC-DC adapters, there are wall, desktop, travel and universal variants. These are typically used in laptops, digital cameras, mobile phones, MP3/ MP4 players and other portable devices.

New models meet EPS 2.0 or EUP II standard and come with interchangeable plugs. Units from Hangzhou Yukingda are compatible with US, EU, UK, SAA and EK sockets.

Most variants also have fixed frequency control circuit, overcurrent and, -voltage, and short-circuit protection.

The key inputs for production are the passive components, ICs, metal, plastic, casings and fans, taking up 70 percent of the total costs. Suppliers usually source requirement locally, but some such as Kuantech turn to foreign providers to ensure quality.

Prices are forecast to climb by 20 percent in 2012 as a result of high material and labor outlay and the yuan’s appreciation against the US dollar. In 2011, the cost of components rose by 15 percent.

Elevated per formance and low energy consumption are the buzzwords in Taiwan’s switching power supplies line. Releases deliver up to 7,200W and integrate power-saving features amid trends for environment-friendly yet high-efficiency models.

MSTronic Co. Ltd is slated to launch 28V variants and 1,000W kinds for industrial applications. It manufactures SPS for PCs and radio base stations.

Units targeted at computers support 100 to 300W, while servers deliver 500 to 600W. Makers also offer 7,200W versions.

To raise product value, some models, particularly those designed for manufacturing equipment, come with remote controls. Triple-and quad-output kinds are likewise available to accommodate various requirements.

Selections comprise hot-swappable, modular, universal input and redundant types, which are employed in networking and office devices.

There are 40 to 50 enterprises engaged in the line in Taiwan, about 30 of which are small and midsize operations. Most provide customization and safety checks while ensuring quick delivery. FSP Group, for instance, has in-house testing capability for CSA, CTDP, TÜV, NEMKO and UL. The supplier also has equipment for evaluating EMI, noise and vibration.

Robust demand from assemblers of computer, communication and consumer electronics products keeps the industry buoyant. Despite this, companies face several challenges, foremost of which is price competition. Declining orders from the PC segment is also posing problems, although applications such as LEDs, game consoles, LCD TVs, servers and telecom devices hold market potential. FSP Group and FranMar International Inc. have ventured into emerging fields, including medical electronics.

Eljintek Inc.
(Taiwan)

Model: PSU25
Description: 100 to 240VAC input voltage; 65% efficiency; overvoltage, -current protection; dual or triple output; CE, UL 1950, CSA, TÜV

Foshan Better Technology Co. Ltd
(mainland China)

Model: CSS120-24
Description: 100 to 265VAC, 50/60Hz input, 24 to 48V, 2.5 to 5A constant voltage; for stage lighting, road, tunnel, miner’s lamps; 127x82x40mm

FranMar International Inc.
(Taiwan)

Model: FRM Series
Description: 90 to 264VAC input voltage; 4 to 160W output; interchangeable plugs available; wall-mount, desktop types; for medical equipment; CEC, CB, CE, PSE, CCC, FCC

Kuantech (Shenzhen) Co. Ltd
(mainland China)

Model: KSAFK1200620T1M2
MOQ: 2,000 units
Delivery: 20 days
Description: 100 to 240VAC input voltage; 50,000hr MTBF; overload latch-off protection; natural convection cooling; 0.5% annual field failure rate at 25 C

Power-Win Technology Corp.
(Taiwan)

Model: U-Channel
MOQ: 200 units
Delivery: 28 days
Description: 90 to 264VAC, 47 to 63Hz input, 12 to 48VDC output voltage; 85% efficiency at full load; 127x81x38.6mm; UL, CSA, TÜV, NEMKO, CB, CE, FCC

Shenzhen Tenwei Electronics Co. Ltd
(mainland China)

Model: TA01
MOQ: 2,000 units
Delivery: 15 days
Description: 100 to 240VAC, 47 to 63Hz input, 5VDC output voltage; 1,000mA output current; overload, -current, -discharge, short-circuit protection; 10 to 40 C operating temperature; for MP3, portable media players

Sinrace Technology Co. Ltd
(mainland China)

Model: JRT350M2-001
Description: 165 to 300VAC, 47 to 63Hz input voltage; 350W power output; ±1.5% output current and voltage accuracy; ≥200,000hr MTBF; for telecom equipment