Digital Power

Looking to get a digital power control
headstart with flexibility and power.

Are you frustrated with analogue control of power electronics? Anxious about meeting the high efficiency challenges while at the same time really frustrated that your digital power development is not progressing?

When it comes to electronic design and manufacturing, ELMG are the experts. With analogue it is impossible to quickly change to way the control is done. Lots of newer high efficiency converters have control that can be best implemented in digital form. And other people’s power converters are obviously digitally controlled when you open them. If you are looking to upgrade your digital power system, choose a reliable electronic designer and contact ELMG Digital Power today.

This current controller subsystem, implemented in an FPGA or DSP, uses multiplications and additions (MACs) to implement vector rotators, PI controllers as IIR filters and Space vector modulators for three phase PWM.

Analogue control – getting left behind

Keeping on using analogue control is not going to meet what your manager and marketing team want from converter performance. Forcing your team to stay using analogue control will end up getting the company further behind. And customers demand high performance power. Your product might not be finished on time and the lost sales could impact the top and the bottom line. With the trends in power converters analogue control will most likely not meet your requirements for your next high efficiency application. A big risk is that there is no suitable power controller without going digital.

Solution

The ELMG digital power eco system

Digital power is flexible, powerful and exceptional value. The repeat cost on software and firmware is zero. Leverage the power of digital control of power electronics now. We are specialist in digital and power and control and how the three go together. This is a unique capability in power electronics, converter stability and digital control. For you it is just seamless. And the eco system means that we will support you with all our technical know-how as needed including power converter design, high speed guaranteed low latency rugged communication links, and product compliance in a frame work to deliver long term sustainable solutions.

Output from the Xilinx FPGA tool for a Phase Locked Loop implemented with a CORDIC block.

ELMG Digital power specialists

There are often specialist designers in power or digital systems. Treating the two as separate problems leads to power designers not taking care of the software or numeric digital issues. And the digital guys just don’t know power. With ELMG it is seamless between the power and the digital. Our digital power eco system means you get help, know-how and our commitment to sustaining your business.

Our Purpose

At ELMG Digital Power, our goal is to design and build the best digitally controlled power electronics systems. By doing so, we can change the world.

For over twenty five years, we have worked on digitally controlled power converters for a range of purposes including motor drives, appliances and power quality systems and look forward to taking on new challenges. We place emphasis on quality and are always looking for ways to improve. Our design, development and know how sharing through training and partners approach has become our signature, with all of these factors fitting together seamlessly in the eco-system of solutions, training and support we provide.

FPGA digital power controller hardware block diagram. FPGA digital power controllers provide the flexibility to build custom peripherals and include all the communications functions on the same chip. A soft core processor in the FPGA provides the sequencing and configuration.

Proven digital power electronics technology
know how

With more than twenty five years of digital power electronics expertise with large corporates and small companies ELMG digital power technology is a real competitive advantage. We have invested in the best digital power tools including Plecs, Matlab, Altium, digital scopes, current probes and VHDL tools.

Digital power is the direct control of electrical power with a microprocessor or DSP or FPGA creating the power switches gate drive signal. This gives flexibility but with this great flexibility and control power comes some new challenges.

Digital control loop design

Digital power control loops are sampled data systems so closing the control loop is done using integrators and filters that are implemented in code using difference equations. The best way to implement these filters and integrators is with second order IIR filter blocks. Digital systems have quantisation and numeric precision that needs to be taken care of while at the same time managing the dynamic range and noise performance. Any digital system has processing delays that can impact stability margins.

Sample rate

The digital sampled data control systems are controlling switching power converters. Matching the sampling rates to the switching rate to avoid aliasing is the key to getting digital power working. Often times in digital power electronics controle it is necessary to avoid the phase delays of aliasing filters by removing the filters. By treating sampling as a modulation the aliasing products can be made smaller than the least significant bit.

How much better is digital.

Digital possibilities are numerous. By putting switching instants exactly when you want them for each converter operating condition it can be possible to get a 2% increase in efficiency from 92% to 94% without making a single hardware change. Linearising converters’ control transfers to increase bandwidth is a very useful feature of digital control. Using repetitive digital filter techniques can provide really low distortion currents in a solar inverter or low THDs in UPS voltages. Other great features include are updating the control algorithms in the field and having the digital controller be able to measure its own control transfer.

Is digital power right for my price point.

Digital power control systems are implemented on microprocessors, DSPs, FPGAs or ASICs. Each of these technologies fits a price point and suits a certain production volume. ASICs have high tooling costs but very low silicon cost so suit high volume. FPGAs and DSPs are perhaps suited to medium to high volume and microprocessors suit the low cost applications. Digital power is even already available from silicon vendors. ELMG IP Core blocks for use in FPGA based power controller provide flexible solutions that are useful for low volume and medium volume production.