Similarly, Emerson Network Power is integrating its uninterruptible power supplies (UPSs) with Asset Management Suite (AMS) software to monitor UPS performance. "In many cases, power systems and their backups have been reliable for decades, so users tend to forget about them after commissioning, and no longer know what to do when alerts and emergency calls eventually come in," says David Vasselin, market and business development vice president for Emerson Network Power's industrial systems division. "Now users want UPSs that are easier to understand and maintain, and this is why we've integrated them with AMS in electronic device description (EDD) software and human-centered design principles. We ran through all the UPS alert situations and added them to the EDDs to give users a hierarchy of alerts and how to troubleshoot them."
Standard Pieces for Specific Puzzles
To help reduce the time it takes to integrate power supplies with their control-based counterparts, Mark Wilkins, chief engineer at Acopian, reports his company is building IP addresses, Ethernet and USB interfaces and some control functions directly into its 0-30 kV power supplies "There's a lot more fluctuating inputs these days, typically between 90 V and 265 V, so we designed a universal input to handle them without having to flip a switch," says Wilkins. "In general, we now have more programming and communications options for applying power more efficiently, and these are allowing power supplies to interface with other equipment, talk to each other and synchronize efforts. For example, in a water ionizing application to purify water for plating, a controller can tell a power supply to turn on; it can report back in a few hundred milliseconds; and be adjusted much faster than manually for more consistent plating with less feathering."
Likewise, some power supplies are adding intelligence that allows them to be more easily monitored and managed, according to Kai-Uwe Bronzel, product consultant for U.S. power supplies and power security at Siemens Industry. "We recently built a relay contactor module into our Sitop power supplies that can bring a signal back to upper-level control systems," says Bronzel. "This lets users check on their input and output voltages, observe trends in their 24-Vdc supplies, and prevent more interruptions and potential failures."
Sharonda Wamer, Siemens' product marketing manager for U.S. power supplies and power security, adds that many power supplies and related systems are following the lead of Europe's suppliers, and moving from 230 Vac or 120 Vac to 24 Vdc. "More customers have applications that depend on critical 24 Vdc power, so we provide solutions to maintain it," says Wamer. "These include our 'dc ups' with battery backup, redundant solutions with two power supplies for load sharing, and switched-mode power supplies. These use an electronic method that draws less current than regular mechanical supplies when reacting to short circuits, and this means fewer trips, more and better identification of potential overloads, and fewer lost circuits."
Merging Power and Control
To combine control and power even more tightly, National Instruments and the National Renewable Energy Lab have combined NI's single-board Reconfigurable I/O (RIO) and added its standard General Purpose Inverter Controller (GPIC) board for 50-kW and up power supplies, which primarily use custom circuit boards.
In fact, Dynapower Corp. has developed power converters for grid-tied energy storage based on NI's LabView RIO architecture and RIO GPIC (Figure 2). Advanced carbon batteries are useful for grid storage because they have a long lifecycle, fast charge/discharge and deep-cycling capability, but they require a unique power conversion and inverter system such as Dynapower's to stabilize performance and provide these benefits.
"LabView and GPIC development platforms reduced our development cost and risk compared to a full-custom controller design," says Kyle Clark, Dynapower's advanced systems engineering manager. "We were able to reduce development time for our power converters from 72 weeks to 24 weeks. FPGA devices in particular, which now include embedded DSP cores inside the fabric, are a real game changer. We can precisely control the flow of power, run multiple control loops in parallel and reconfigure the hardware at a silicon level even after it's deployed to the grid."