Industrial Applications of Power Semiconductors: Drives, UPS and Process Equipment

Industrial applications of power semiconductors include motor-speed control, regulated power supplies, backup conversion, welding, induction heating and battery formation. The devices switch, rectify or direct electrical energy so equipment can deliver a controlled output. A factory motor drive and a battery tester can use similar component families while demanding very different waveforms, accuracy and protection. Understanding the application first is therefore more useful than choosing a transistor technology from a voltage range alone.

Last updated: October 23, 2026

Industrial applications of power semiconductors by circuit role

A power stage may turn AC into DC, convert one DC level to another, or synthesize an AC output from DC. Some stages support power flow in both directions. Others provide a controlled current to a process load. These functions establish the current paths and blocking states that the semiconductor must support.

Power rectifiers generally provide conduction and blocking without the same commanded control as a transistor switch. MOSFETs and IGBTs give the controller power-switching functions under their supported gate conditions. Thyristors can provide another kind of controlled conduction, with turn-off behavior depending on the exact device type and circuit. A conventional SCR is not simply an IGBT with a different name.

Use a block diagram for the equipment and then a state-by-state schematic for the stage under review. The power device introduction explains the building blocks. Their importance in industry comes from how they coordinate with controls, loads, storage and cooling, not from appearing in every machine in the same arrangement.

Motor drives turn a DC link into controlled phase outputs

In a representative variable-frequency drive, an input stage supplies a DC link and an inverter bridge applies controlled voltage states to the motor phases. The control system regulates the required operating behavior using current and other measurements. MOSFETs, IGBTs or other supported switch arrangements may be candidates for the bridge.

Inductive current continues during switching transitions, so diode or controlled reverse-current paths matter. Their commutation affects the opposite switch’s stress, loss and ringing. The transistor’s on-state behavior alone cannot characterize the complete phase leg. Gate timing and the current loop must be assessed alongside the device data.

TI’s TIDA-00366 three-phase inverter reference design is one primary example of a complete drive power stage with isolated drive and sensing. Its files show how these functions interact. An industrial pump, servo or fan can have different duty and control requirements, so the example is a learning reference rather than a universal bill of materials.

Braking exposes the limits of the input architecture

When a motor feeds energy back into its drive, the DC-link voltage can rise unless that energy has a supported destination. An ordinary diode input bridge does not provide a commanded return path to the AC source. A braking arrangement may dissipate energy in a resistor, while an appropriate regenerative front end can support another path. The required method depends on the equipment.

A large bus capacitor can absorb some energy, but its capacity and maximum voltage remain limited. It is not a universal substitute for a defined braking strategy. Evaluate the stop or regeneration event, initial bus voltage, available energy and the response of the associated switches and controls.

Infineon’s motor-control application guide discusses regenerative braking in a particular control implementation. The broader lesson is architectural: current reversal at the motor does not prove that the whole drive can return energy to the supply. Include the input stage and energy destination in the review.

Industrial power supplies regulate the equipment’s rails

A controller cabinet can need several regulated rails for logic, sensors, actuators and communication. An AC-fed supply may include rectification, input conditioning, an isolated switching stage and output rectification. A DC-fed supply may require a different arrangement. Identify the actual conversion stages instead of assuming every industrial rail begins at mains AC.

Switching frequency, transformer or inductor behavior, load transitions and output filtering shape semiconductor duty. A rectifier at a low-frequency input and a diode at a rapidly commutated output face different requirements inside the same enclosure. Their average currents and reverse peaks need their own calculations.

The switching power supply explanation separates conversion from filtering and regulation. For industrial use, add input disturbances, the local cabinet temperature, supported isolation and the defined load profile. A regulated output is a system result; it is not guaranteed merely by selecting a transistor with a large voltage rating.

UPS equipment manages conversion and transitions

An uninterruptible power supply combines an energy source and a conversion arrangement to support its specified loads when the normal source changes or disappears. Online, line-interactive and other architectures can route power differently. Rectifiers, inverters, chargers and transfer functions should be read from the actual system diagram.

TI’s UPS design resources show the relationship among power conversion, sensing and control. Battery-side charging and discharge may require bidirectional behavior, while an AC output stage must meet its specified load and waveform requirements. A component capable of reverse current does not alone establish a bidirectional UPS.

Check source transfer, startup, battery range, overload and output faults as separate conditions. The semiconductor that is acceptable during steady full-load conversion can still be challenged by a transfer event or abnormal load. The supported backup time also depends on storage and the actual load, not solely on the inverter’s switch ratings.

Welding and induction heating impose process-specific duty

A welding power stage regulates energy delivered to its process. Arc initiation, changing load and intermittent operation can produce a demanding current and thermal profile. The relevant semiconductor assessment includes that profile, the control response and the supported fault behavior. A short-circuit characteristic, if specified, is conditional rather than permission for indefinite abnormal operation.

Induction heating uses a varying electromagnetic field to transfer energy to a workpiece. A resonant power stage can have switching conditions shaped by the tank circuit and load. Device voltage and current need not be inferred directly from input power or supply voltage. Changes in coupling or load can alter the operating point.

Infineon’s application note on reverse-conducting IGBTs and resonant applications provides a concrete explanation of device behavior in induction-heating arrangements. Some architectures can reduce particular switching losses under their intended conditions. That does not remove conduction loss, thermal limits or the need to assess operation away from the nominal resonant condition.

Battery formation needs accurate controlled current in both directions

Battery formation and test equipment regulates charge and discharge profiles while measuring the cell’s response. The power stage must deliver controlled current and voltage, and the measurement path must be accurate enough for the process. Some architectures recover discharge energy; others dissipate it. That capability comes from the complete arrangement.

TI’s TIDA-01041 battery tester reference design is a manufacturer example of controlled charging and discharging. Its specific documented performance should not be transferred to unrelated equipment. Study the topology, sensing and control together to understand what supports the result.

Here, semiconductor selection cannot be separated from measurement accuracy. Conduction loss affects efficiency and temperature, while sensing offsets, reference behavior and calibration affect the process data. A very low-resistance switch does not guarantee accurate current regulation. The design must meet both the power-handling duty and the allowed measurement error over the relevant operating conditions.

Compare applications by the condition that governs selection

Equipment names provide context, but the limiting condition usually belongs to a particular stage. A continuously loaded drive, a pulsed welding supply and a low-voltage high-current tester can require different priorities even if their output-power labels look similar. Define which waveform, temperature or response requirement governs each position.

Application	Power-semiconductor task	Important application check
Motor drive	Switch phase current and manage commutation	Braking energy, load current and gate timing
Industrial supply	Rectify and regulate power	Input range, charging pulses and load transitions
UPS	Convert from supported sources to protected loads	Transfer, storage range and output faults
Welding/heating	Control process energy	Changing load, pulse duty and resonant stress
Battery test	Control charging/discharging current	Bidirectionality, accuracy and temperature drift

This approach avoids a fixed rule that MOSFETs always win below one voltage and IGBTs above it. The IGBT vs MOSFET guide compares the relevant mechanisms. Match feasible candidates at the intended conditions, including the companion diode and installed heat path.

Calculate heat from the correct efficiency definition

Efficiency is useful output power divided by input power at stated conditions. For an illustrative stage delivering 10,000 W at an assumed 97% efficiency, input power is 10,000 / 0.97, approximately 10,309 W. The difference is approximately 309 W. Taking 3% of the output would give 300 W and answer a slightly different calculation.

That assumed total does not identify semiconductor loss alone. Magnetics, conductors, control supplies and other elements may contribute. Determine the loss distribution before sizing a heatsink for the switches. Multiple junctions can share a cooling assembly and affect each other’s local temperature.

A cabinet’s room temperature is not necessarily the temperature next to the power stage. Airflow, enclosure, mounting and neighboring equipment matter. Use the supported thermal paths and check the relevant transient duty as well as steady-state operation. A maximum junction-temperature rating does not establish acceptable lifetime for every repeated heating cycle.

Industrial protection must match the disturbance and source

Long wiring, inductive loads and connected equipment can create electrical disturbances, but their energy and waveform differ. A board-level ESD protector, a surge clamp and a controlled power disconnect have distinct functions. Define the event before selecting a protection device from package size or a pulse-wattage headline.

TI’s TVS selection guidance explains the normal-voltage and clamp window. A TVS can be useful for a supported transient; sustained overvoltage requires a separate current and energy assessment, often including interruption or limitation. It is not reasonable to assume that a Zener or TVS can clamp a powerful rail continuously merely because its nominal voltage is appropriate.

Preserve the current paths, device conditions, thermal arrangement and affected test results with the design. Industrial reliability follows from a supported operating envelope and controlled assembly, not a technology name or catalog superlative. Start the next selection review with the actual conversion job and its most demanding state, then use that evidence to choose the devices.

Continue through this engineering topic

For the complete selection, design, verification, and troubleshooting path, explore the Power Supply Application Design Hub.

• Practical guide: What Is a Switching Power Supply? How SMPS Works
• Practical guide: How a Power Adapter Turns Wall Power Into 5 V: A Guided Tour
• Practical guide: How Do LED Bulbs Work, and Why Do They Last Longer?
• Ask Good-Ark technical support about this application