Power Electronics

The most important information in brief

What is power electronics?

Power electronics is the part of electronics that deals with electrical energy at technically relevant power levels. While classical electronics often captures measured values, processes signals, or outputs control commands, power electronics handles the actual energy conversion. This includes switching, regulating, rectifying, inverting, limiting, distributing, or storing electrical energy within a system.

In a project, power electronics usually doesn't start with a single component, but with a technical task. A motor is to be controlled, a battery is to be charged, an actuator is to generate a defined force, or an assembly is to provide multiple supply levels from an input voltage. This results in requirements for voltage, current, switching frequency, load profile, installation space, temperature range, protection functions, and control.

PICKPLACE therefore views power electronics as an interplay of circuit design, component selection, thermal considerations, layout, simulation, and calculation. A transistor, a driver, an inductor, or a capacitor cannot be evaluated in isolation. The crucial factor is how the components work together in the respective operating scenario. For example, in switched converters, switching edges, parasitic inductances, current paths, and ground management directly affect behavior, losses, and susceptibility to interference.

Power electronics include various circuit types. These include DC/DC converters, AC/DC converters, inverters, motor output stages, charging electronics, current limiters, protection circuits, and electronic load switches. Even seemingly simple tasks can become challenging to implement when high currents, rapid load changes, or tight thermal limits occur.

A key part of the work is translating electrical requirements into a robust technical design. This involves considering input voltages, output values, load cases, turn-on transients, short-circuit conditions, power losses, and temperature rises. The resulting findings are incorporated into the circuit diagram, PCB layout, cooling concept, and test strategy.

Power electronics are needed for machines, vehicles, or systems to control and convert electrical energy. This enables efficient operation, precise control of motors and other components, and the integration of different power sources.

In machines, vehicles, and plants, power electronics are needed wherever electrical energy is not just to be provided, but to be used in a targeted manner. A motor requires a control system that influences speed, direction, or torque. A charger requires a control loop that adapts current and voltage to the state of the energy storage. A power supply must generate stable supply voltages for further modules from an input voltage. An actuator requires an output stage that derives a physical movement or force from a control signal.

In machines, the connection between the control level and the power level is often the primary focus. A control system specifies setpoints, while power electronics provide the electrical energy for motors, valves, magnets, or heating elements. Control, feedback, protection behavior, and shutdown concepts must all match. If a motor jams, a load unexpectedly increases, or a cable is damaged, the electronics must support defined reactions. Such questions are considered during the design phase so that the later hardware functions not only during normal operation.

In vehicles, further requirements are added. Voltage levels, onboard network behavior, load changes, start-up and shutdown processes, and thermal boundary conditions influence the design. An assembly can be exposed to strong temperature changes or varying load profiles during operation. Power electronics must therefore be dimensioned to cover the expected operating conditions. This process considers power losses and thermal paths because electrical losses are converted into heat, and this heat must be dissipated.

Systems often involve the distribution, conversion, and protection of electrical energy across multiple modules. A central power supply can feed various loads, while decentralized converters provide local voltages. Power electronics must fit the system architecture. Conductor paths, protection concepts, inrush currents, and interactions between assemblies can influence the behavior of the entire system.

For PICKPLACE, such a project first means clarifying the electrical requirements. What load will be powered? What input voltage is available? What current peaks will occur? What operating modes are intended? What heat dissipation is possible? What interfaces to the control system are there? Only when these questions are answered can it be decided which circuit topology, which semiconductors, which passive components, and which protective functions should be used effectively.

Another project aspect is the coordination between electronics, mechanics, and software. Mechanics often determine installation space, cooling surfaces, and mounting points. Software influences control, switching behavior, diagnostics, and error responses. Electronics must connect both levels. If these interfaces are clarified late, layout changes, component selection, or housing concepts often arise. PICKPLACE can structure such dependencies early and prepare technical decisions.

When does normal electronics become power electronics?

The transition from conventional electronics to power electronics is not defined by a single fixed boundary. In projects, it typically becomes apparent when current, voltage, heat generation, or switching operations can no longer be treated as incidental. As soon as energy conversion significantly influences the circuit's behavior, the electronics must be considered power electronics. In the automotive and industrial sectors, power electronics generally starts around the 48V range. In energy technology, power electronics is regularly only discussed from 1000V upwards.

A typical example is a control line that only outputs a digital signal. As long as it controls an input, the task remains within the scope of signal technology. However, if the same control is intended to power a motor, a relay, a coil, a heating element, or a larger LED group, different requirements arise. The output must supply or switch current, switching spikes must be considered, freewheeling paths may be necessary, and the power dissipation in the component must be calculated.

The printed circuit board also changes the perspective. With small signal currents, impedance, noise margin, or logic levels are often in the foreground. With higher currents, trace widths, copper areas, contact resistances, connectors, heating, and current return become central design parameters. A trace is then not just a connection, but part of the electrical and thermal system.

Another indicator of power electronics are switched energy paths. When semiconductors switch loads on and off rapidly, steep current and voltage changes occur. These processes can create overshoot, disturbances, additional losses, or stress on components. Therefore, driver circuits, gate resistors, snubbers, freewheeling paths, ground concepts, and layout management are incorporated into the design.

From a project perspective, normal electronics become power electronics at the latest when a fault can lead not only to an incorrect signal but also to overheating, component damage, unexpected movement, or shutdown of a system. Therefore, protective functions must be considered. These can include current measurement, temperature monitoring, voltage monitoring, shutdown paths, or defined start and stop states.

PICKPLACE does not delineate these topics schematically, but rather based on the specific task. An assembly with moderate performance can be demanding if it has limited installation space, low heat dissipation, or rapid load changes. Conversely, higher performance can be manageable if the load profile, cooling, and circuit topology are well-matched. The technical assessment of the actual operating conditions is crucial.

Typical Technologies and Frameworks

• Microcontroller Infineon AURIX TriCore
• MOSFET Infineon OptiMOS
• Gate driver Power Integrations SCALE
• Simulation LTspice
• PCB CAD Altium Designer

Our Services

PICKPLACE supports power electronics projects with design, simulation, development, and calculation. The process begins with the technical task: What energy needs to be converted, switched, or distributed? What loads are connected? What boundary cases need to be considered? What interfaces exist with control, mechanics, and software?

During the design process, stresses, currents, load profiles, switching states, and power losses are considered. This forms the basis for selecting suitable circuit topologies and components. These include power semiconductors, drivers, inductors, capacitors, resistors, protective devices, connectors, and measurement paths. The selection is not made based on individual datasheet values alone, but is evaluated in the context of operating conditions, temperature, and installation environment.

We use simulations to narrow down circuit behavior before implementation. They can help investigate power-up sequences, control behavior, current profiles, voltage ranges, or the loads on individual components. Simulation doesn't replace measurement on a real setup, but it reduces uncertainties in an early project phase and makes technical assumptions verifiable.

In design, it's about schematic and PCB layout. In power electronics, the layout significantly influences electrical behavior. Current loops, ground reference, thermal copper areas, placement of capacitors, drivers, and power semiconductors, as well as the separation of signal and power paths, are determined on a project-specific basis. The goal is a layout that fits the chosen circuit, the available space, and the expected operating conditions.

Calculations are used to make technical decisions understandable. This includes power loss estimations, current loads, voltage margins, temperature increases, sizing of passive components, or the evaluation of limiting cases. Such calculations create a basis for component selection, layout decisions, and subsequent tests.

When examining existing assemblies, PICKPLACE can also analyze error patterns and weaknesses. These include overloaded components, thermal anomalies, unexpected shutdowns, unstable supply voltages, or problems with load switching. The results are processed in such a way that concrete changes to the circuit, components, layout, or operating parameters can be derived from them.