In today’s world, the demand for power electronics has risen considerably. Dozens of governments and NGOs have been trying to cut back on carbon emission and focus on clean energy, which has led to an increased demand for new types of power electronics used in power conversion equipment.
Power conversion equipment uses these power electronic devices as power semiconductors to change and control the flow of electric energy. Power conversion solutions generally convert power from one form to another – like from AC to DC and vice versa.
What Is Power Conversion?
In our day to day lives, we come across dozens of electronic devices, from mobile phones to elevators. What they all have in common is the need for a reliable and stable source of DC power.
Where DC is not available from an MPS power supply unit or otherwise, power conversion kicks in to provide it. Before I get into the types of power conversion devices used, below are some applications of power conversion.
Applications
Battery Chargers for Submarine Maintenance
Batteries run a submarine’s propulsion engine so they are a very crucial component of a submarine. These batteries should be capable of storing large amounts of energy to power the submarine.
The process of charging and discharging submarine batteries extends their life shelf. As such, design and manufacture of high current battery charges for rapid charging and discharging is very important.
Renewable Energy
Most renewable energy solutions use at least one form of power conversion.
Inverters are used to convert DC from wind and solar energy to usable AC energy for instance. After the DC is converted, it can be transferred for use commercially in power grid systems.
Some hybrid microgrids with multiple renewable power sources may have several multilevel inverters – typically DC/DC and DC/AC.
Ships on the Shore
Ship equipment often has different power requirements than the countries the ship is passing through. They have to now use the country’s power grid for power.
Power conversion solutions convert the voltage and frequency from that of the country’s grid to match what the ship requires. The vessels can now plug into the grid power supply to reduce idling.
Types of Power Conversion Devices
Depending on the type of power needed by a resource, power from your Monolithic Power Systemsf needs to be converted if necessary.
There are three types of power conversion devices in use today: AC/DC power supply, DC/DC converter and DC/AC inverters. Of the three, the AC/DC and DC/DC are the most used.
Linear Power Supply
The linear MPS power supply converts AC line voltage to DC output. By doing so, it performs these functions:
Input transformer
It changes the high AC line voltage via a step down transformer to a more suitable voltage required by the system. The preferred voltage is usually from 3.3.V to 24 V.
Input rectifiers
Changes the now stepped down AC voltage to DC voltage.
Filtering
Monolithic Power Systems – through output capacitors – smooth the ripple of the rectified AC voltage to an average sustainable level.
Output regulation
MPS power supply units use series regulator components that provide constant output voltage in relation to line, load and temperature changes.
Isolation
In isolation, separation of the input and output of the power supply occurs to provide both safety and line noise isolation.
Common AC/DC Switching Power
Buck converter
This type of converter is often used in switching power supplies with output levels up to 1000W. The buck converter operates like a forward converter and there is no input-output isolation for the circuit.
The high input DC voltages are regulated to a lower level by pulse width modulation of the switch.
Forward converter
The forward converter stores energy in the output inductor rather than the transformer. When the transistor switches on, output voltages generated in the secondary current flow through the diode into the inductor.
The longer the switch stays on relative to when it’s off, the higher the average secondary voltage and the higher the open current load.
Push pull converter
The push pull converter is technically a variant of the forward converter with one exception; the two switch elements are used on the primary side of the transformer.
