SUNTAN TECHNOLOGY COMPANY LIMITED · HIGH-POWER FILM CAPACITOR SPECIALIST
Figure 1: Suntan® TS24 conduction cooled capacitor designed with robust mounting surfaces for direct thermal management on liquid-cooled cold plates.
High-Power Thermal Management with Conduction Cooled Capacitors: Suntan TS24 Engineering Guide
In next-generation medium- and high-frequency power electronics, thermal dissipation is frequently the definitive bottleneck constraining system miniaturization and power density. As switching frequencies rise into the tens and hundreds of kilohertz and circulating currents surge past several hundred amperes, conventional convective airflow cooling methods rapidly reach their physical limits.
As an experienced conduction cooled capacitor manufacturer, Suntan Technology Company Limited® engineered the TS24 Series specifically for high-power, high-frequency resonant circuits. By conducting internally generated thermal energy directly into mounting surfaces, busbars, and liquid-cooled cold plates, the TS24 delivers ultra-low thermal resistance, high dv/dt endurance, and exceptional reactive power handling (up to 800 kVar) within a remarkably compact structural envelope.
Why Conduction Cooling Outperforms Air Cooling in High-Power Systems
Operating high-power film capacitors inside compact, dust-tight, or liquid-sealed enclosures (such as IP65/IP67 cabinets) imposes severe thermal management challenges:
- Direct Solid-State Thermal Path: Instead of relying on low-efficiency air convection, the TS24 establishes an ultra-low thermal resistance (Rth) interface by bolting directly onto chassis heatsinks or water-cooled copper cold plates.
- Internal Hotspot Prevention: Massive circulating tank currents generate heavy Joule heating. Direct conduction extracts heat immediately from the low-loss dielectric winding, preventing localized hotspot accumulation and thermal runaway.
- Compact Enclosure Compatibility: Ideal for space-constrained power converters where forced air fans cannot be deployed due to acoustic noise, contamination risks, or hermetic sealing requirements.
- Extended Operational Reliability: Under rigorously controlled hotspot temperatures, the TS24 maintains stable capacitance values and delivers an operational service life of up to 200,000 hours at rated conditions.
Suntan® TS24 Series Technical Specifications Matrix
The table below outlines the core operating ratings, dielectric characteristics, and technical documentation references for the Suntan TS24 series:
| Series Platform | Dielectric & Cooling Structure | Key Electrical Ratings | Reactive Power | Documentation |
|---|---|---|---|---|
| TS24 Series | Low-Loss Polypropylene Film / Direct Conduction Plate & Busbar Mount | Rated Voltage: 400 VAC – 1,000 VAC Capacitance: 0.1 μF – 84 μF tan δ ≤ 5 × 10-4 (1 kHz) |
300 kVar, 600 kVar, 750 kVar, 800 kVar | TS24 Page & PDF → |
Key Industrial Applications for Conduction Cooled Capacitors
The TS24 series is engineered to excel in demanding industrial environments requiring continuous high-power throughput and extreme frequency stability:
- Induction Heating & Melting Furnaces: Functions as the primary resonant tank capacitor, carrying hundreds of amperes across LC tank circuits while securely bolted onto water-cooled copper cold plates.
- High-Frequency Resonant Inverters & Converters: Supplies reactive compensation and energy storage in LLC, LCC, and full-bridge zero-voltage switching (ZVS) power architectures.
- High-Power Industrial Welding Equipment: Withstands heavy pulse loads, repetitive high-current discharges, and rapid switching transients with elevated dv/dt rates.
- EV High-Power Wireless Power Transfer (WPT): Enables primary and secondary magnetic resonant coupling with a high quality factor (Q) and minimal transmission loss.
Engineering Selection Checklist for High-Power Film Capacitors
When sizing a conduction cooled capacitor for your system design, hardware engineers should systematically verify the following technical parameters:
- 1. Working AC/DC Voltage: Calculate continuous RMS voltage, peak working voltage, and appropriate safety margins against harmonic-induced overvoltages.
- 2. Continuous RMS Current (IRMS): Compare maximum circulating currents against current-versus-frequency de-rating curves to prevent thermal overload.
- 3. dv/dt Withstand Capability: Ensure the capacitor's rated dv/dt tolerance (V/μs) accommodates switching rise times (Ipeak = C × dv/dt).
- 4. Operating Frequency: Match the resonant tank frequency with the dielectric dissipation factor (tan δ) to minimize high-frequency ESR losses.
- 5. Thermal Path & Heatsink Interface: Verify mounting interface flatness (≤0.05 mm), apply a thin thermal interface material (TIM), and adhere strictly to specified busbar torque limits.
- 6. Rated Reactive Power (kVar): Confirm required kVar capacity under full-load continuous duty cycles.
Frequently Asked Questions — Conduction Cooled Capacitor Engineering FAQ
A conduction cooled capacitor is a specialized high-power, high-frequency capacitor designed to transfer internally generated thermal energy away via direct solid-state contact with an external heatsink, cold plate, or heavy-duty busbar mounting surface, rather than relying on natural or forced-air convective airflow. This solid-state thermal path provides superior thermal conductivity and allows components to withstand hundreds of kilovolt-amperes reactive (kVar) within compact footprints.
Explore TS24 Conduction Cooled Design →Engineers should specify conduction cooled capacitors when power conversion circuits handle extreme continuous RMS currents (hundreds of amperes), high operating frequencies (tens to hundreds of kHz), compact sealed enclosures (such as IP65/IP67 equipment), or operating environments where restricted airflow prevents conventional air cooling from preventing thermal runaway.
Conduction cooling creates a direct metallic thermal pathway with minimal thermal resistance (Rth) between the internal film winding and the cooling plate. By conducting heat efficiently through the mounting surface, internal hotspot temperatures are kept low, stabilizing capacitance, suppressing dielectric degradation, and ensuring dependable operational stability under continuous full-load excitation.
dv/dt defines the maximum permissible rate of voltage change across the capacitor over time (measured in V/μs). In high-frequency resonant circuits and fast-switching inverter bridges, rapid commutations create severe dv/dt transients. High dv/dt capability ensures that the capacitor withstands repetitive peak currents (Ipeak = C × dv/dt) without dielectric punch-through or terminal metallization failure.
Equivalent Series Resistance (ESR) reflects the internal ohmic losses within the dielectric film and metallized terminations. Because power dissipation scales with the square of the RMS current (Ploss = IRMS2 × ESR), ultra-low ESR is critical to suppressing self-heating, preserving electrical efficiency, and preventing destructive thermal breakdown.
Review Low-ESR TS24 Technical Specs →Yes. Conduction cooled capacitors are fundamental components in induction heating generators and melting systems. Connected in series or parallel with induction coils to form the resonant LC tank, they manage continuous reactive power (300 kVar to over 800 kVar) and hundreds of amperes of circulating current while securely mounted onto liquid-cooled cold plates.
Absolutely. Capacitors such as the Suntan TS24 are purpose-engineered for series and parallel resonant converters (including LLC, LCC, and tank configurations). Their tight capacitance tolerance, high quality factor (Q), low dissipation factor (tan δ), and extreme current capacity ensure precise resonant tuning and negligible loss under high-frequency operation.
Key applications encompass induction heating and melting furnaces, high-frequency resonant power supplies, industrial welding systems, high-power wireless EV charging platforms (WPT), plasma power generators, and medical RF power equipment.
Follow a structured selection workflow: 1) Verify operating AC/DC continuous voltage; 2) Determine maximum continuous RMS current and switching frequency; 3) Confirm peak dv/dt withstand capability; 4) Calculate required reactive power (kVar); 5) Inspect mounting interface flatness, thermal interface material (TIM), and correct busbar connection torque.
When operated strictly within designated electrical ratings and hotspot temperature limits—supported by proper cold-plate or heatsink thermal management—Suntan TS24 conduction cooled capacitors can achieve an expected service life of up to 200,000 hours at rated conditions. Exceeding rated hotspot temperatures accelerates dielectric aging and proportionally shortens service life.
Suntan® supports power electronics designers, induction heating equipment builders, and resonant converter manufacturers worldwide. For cross-referencing, custom terminal mountings, or sample requests, please contact our technical sales team.
