Technology / Engineering guide
Wind Converter Cooling, Thermal Ratings & Derating
A converter’s nominal power label needs its thermal conditions. Device losses, cabinet surroundings and the intended operating duty affect the heat-removal question. Review the selected equipment’s rating basis rather than importing a reduction factor from another product.
Heat has a source, a path and a reference condition.
Identify the particular converter and where it will operate. A component thermal specification and an assembled cabinet rating describe different boundaries.
01 / Loss heat
Transferred power is not all dissipated as heat.
Electrical power transferred through a converter and power lost inside it are different quantities.
Electrical power transferred through a converter and power lost inside it are different quantities. A heat-removal assessment needs the applicable loss information at the relevant operating condition, not the full nameplate power treated as a heat load.
TI’s power-module discussion illustrates that losses and thermal paths affect allowable operation. Its example device is not a wind converter, so no component current, temperature limit or cooling performance is assigned to MARSTON.
02 / Thermal boundary
Junction, case and surrounding air are different references.
A semiconductor junction temperature, a heatsink observation and cabinet air describe different points.
A semiconductor junction temperature, a heatsink observation and cabinet air describe different points. A thermal parameter must identify the points it connects and the conditions under which it applies. It is not automatically a complete cabinet model.
Ask which point limits the offered equipment and how that condition was assessed. A cool-looking outer enclosure or a low outdoor temperature does not by itself establish the temperature of every internal device.
03 / Installation air
Define the environment at the actual equipment.
Record the converter location, cabinet arrangement and supplier-defined cooling conditions.
Record the converter location, cabinet arrangement and supplier-defined cooling conditions. Distinguish outside weather from the air surrounding the installed device. Other heat-producing components in the same cabinet can change that local condition.
Airflow, liquid cooling or passive heat removal must describe the actual quoted arrangement. A photograph of a fan does not establish cooling capacity, and a general ventilation concept is not an authorised modification to the installation.
04 / Derating
Use the selected device’s conditions and curve.
Derating means a rating is reduced under specified conditions.
Derating means a rating is reduced under specified conditions. Identify whether the supplier’s information limits current, power or another quantity, and retain its temperature, altitude and installation assumptions. Those quantities should not be substituted for one another.
No MARSTON derating curve or universal percentage is given here. A curve for another converter, or for a bare power module, cannot be applied to this package merely because its nominal kW is similar.
05 / Duty
Short output and continuous output need different evidence.
Keep operating duration and loading profile beside the thermal rating.
Keep operating duration and loading profile beside the thermal rating. A brief output observation does not independently establish sustained duty. If the electrical configuration changes, the relevant current and loss state may also change.
Compare the intended project duty with the represented test or rating condition. Separate a verified continuous rating, an explicitly permitted short-duration condition and an unresolved requirement rather than treating them as one capacity.
06 / Review record
Coordinate cooling with the complete package.
A thermal review can identify converter revision, loss basis, cooling method, local conditions, limiting quantity and rating evidence.
A thermal review can identify converter revision, loss basis, cooling method, local conditions, limiting quantity and rating evidence. Name the parties responsible for the equipment and cabinet so a gap has an owner.
Use the hot-climate guide for the wider site assessment. This page supplies no fan sizing, airflow alteration, coolant procedure or protection-setting instruction; those belong to the actual device’s approved documentation.
Continue the review with Wind Generator Winding Temperature & Insulation Class.
Continue the review with Wind Generator Losses & Efficiency Maps.
Continue the review with Dissimilar Metals & Galvanic Corrosion in Wind Equipment.
Extend the thermal evidence review with thermal resistance, heat capacity and transient RC models.
Extend the converter thermal review with semiconductor conduction and switching losses, MOSFET, IGBT and SiC terminology, and device safe operating area conditions.
General background: Texas Instruments: Loss heat and component thermal-path context. These references explain industry concepts; they are separate from the applicable MARSTON product and project documents.
Prepare the information for this review.
Use the checklist to organise the project information. Mark unavailable items and retain document references.
| Review item | Information to provide | Purpose |
|---|---|---|
| Device identity | Converter revision and output boundary | Locate the rated equipment. |
| Loss basis | Operating point and dissipated-power evidence | Define the heat source. |
| Cooling conditions | Method, cabinet and local surroundings | Match the heat-removal boundary. |
| Derating definition | Limited quantity and applicable conditions | Avoid transferring another device’s curve. |
| Duty evidence | Continuous/short-duration state and responsibility | Review the intended installation. |
Engineering questions.
Is converter rated power its heat loss?
No. Transferred power and internally dissipated power are different quantities.
Can outdoor temperature rate cabinet equipment?
The actual local conditions and supplier installation basis must be identified.
Is a component thermal parameter a cabinet rating?
No. Its measurement points and conditions define a narrower boundary.
Does a fan prove sufficient cooling?
No cooling capacity follows from its appearance alone.
Is there a universal temperature derating factor?
No. Use the selected equipment’s applicable rating information.
Does this page authorise cooling changes?
No. It explains review inputs without a modification or operating procedure.
Technical enquiry
Bring your project information to the discussion.
A converter’s nominal power label needs its thermal conditions. Share the available information and the equipment scope you want reviewed in a technical quotation.