In photovoltaic inverters, energy storage converters, and EV charging facilities, high current, high power density, and stringent EMI compliance requirements are exerting pressure simultaneously. Traditional common-mode chokes often struggle to balance "high current capacity" with "low profile and low loss" – they are either too bulky, or run too hot, or lack sufficient high-frequency suppression capability.
The SHINHOM SQ3324 series Power Line Common Mode Choke, with a 15A rated current, 4.0mH minimum inductance, 15mΩ maximum DCR, and flat wire winding process, provides a design solution that balances performance and space for common-mode noise suppression in new energy power systems.
Application Scenario 1: Photovoltaic Inverters – Common-Mode Noise Suppression on the DC and AC Sides
Photovoltaic inverters convert the DC power from solar panels into AC power for grid connection. Common-mode noise issues exist on both the DC side and the AC side – the high-speed switching action of power switching devices generates high-frequency common-mode currents, which couple to the grid and ground through parasitic capacitance.
Core Challenges
- Under high-current conditions, the common-mode choke must have sufficient current carrying capacity
- The inverter's internal space is compact, requiring low-height, small-size components
- Long-term outdoor operation requires wide-temperature capability and a low failure rate
Suitability of the SQ3324 Series
- 15A rated current meets the current requirements of string inverters
- Flat wire winding enables a low-profile design, adapting to compact inverter layouts
- -30°C to +120°C operating temperature range, suitable for outdoor environments
- 4.0mH inductance provides effective common-mode suppression in the target frequency ban
Application Scenario 2: Energy Storage Converters (PCS) – Bidirectional EMI Filtering for Charging and Discharging
Energy storage converters enable bidirectional energy conversion between the battery and the grid. In both charging and discharging modes, the generation mechanisms and propagation paths of common-mode noise differ, imposing bidirectional filtering requirements on the common-mode choke.
Core Challenges
- Under bidirectional operating modes, common-mode noise frequency bands and amplitudes differ
- Under high-current charge/discharge conditions, the choke must maintain low loss and low temperature rise
- Energy storage systems have extremely high requirements for long-term reliability
Suitability of the SQ3324 Series
- Low DCR (15mΩ) reduces power loss during charging and discharging
- Low temperature rise design (<55°C) ensures long-term stable operation
- Single-phase winding reduces stray capacitance, improving high-frequency common-mode suppression
- Flat wire winding improves space utilisation, adapting to the compact layout of energy storage PCS
Application Scenario 3: EV Charging Facilities – EMI Compliance for High-Current Fast Charging
The power level of DC fast charging stations for electric vehicles ranges from 60kW to over 350kW, with output currents reaching hundreds of amperes. The AC-DC and DC-DC conversion stages inside the charging station generate substantial common-mode noise, which must be effectively suppressed by common-mode chokes to ensure the equipment passes EMI compliance certification.
Core Challenges
- High-power fast charging stations place high demands on the current carrying capacity of common-mode chokes
- Limited internal space in charging stations requires low-height components
- Outdoor installation requires adaptation to wide-temperature environments and long-term operation
Suitability of the SQ3324 Series
- 15A rated current is suitable for the filtering requirements of medium-power charging modules
- Flat wire winding enables a low-profile design, saving internal space in charging stations
- Excellent EMI suppression capability, helping equipment pass CISPR and other EMI standards
- Wide operating temperature range adapts to outdoor installation environments
Core Technical Specifications Analysis
High Current Capacity
- Rated current 15A, suitable for high-power supply applications
- Meets the high current requirements of new energy equipment such as PV inverters, energy storage PCS, and charging stations
Low DC Resistance (DCR)
- Maximum DCR only 15mΩ
- Reduces power loss and heat generation
- Improves overall system efficiency
High Inductance
- Minimum inductance 4.0mH (@1KHz, 0.1V)
- Provides excellent common-mode noise suppression in the target frequency band
Low Temperature Rise
- Winding temperature rise <55°C at rated current
- Operating temperature range: -30°C to +120°C
- Subject to PCB conditions and harmonics; ensure coil temperature does not exceed the operating range
Flat Wire Winding Process
- Improves space utilisation and reduces skin effect
- Single-phase winding significantly reduces stray capacitance
- Compared to toroidal cores: smaller inter-turn capacitance and higher insulation strength
Conclusion: Finding the Right Common Mode Choke Solution for New Energy Power Supplies
The SQ3324 series Power Line Common Mode Choke, with its 15A high current, 4.0mH high inductance, 15mΩ low DCR, and low-profile flat wire design, provides a common-mode noise suppression solution that balances performance and space for new energy applications such as PV inverters, energy storage PCS, charging stations, and industrial frequency converters.
For selection recommendations or sample support tailored to your specific application (current, frequency, space constraints), please contact our technical team.
📧 Email: sales@shinhom.com
🌐 Website: www.shinhom.com/
🔗 Product Details & Inquiries: Power Line Common Mode Choke Series