High efficiency electric vehicles demand efficient AC-DC inverters operating at high voltages and temperatures reaching 150°C. SABIC’s ELCRES™ HTV150A films are high-heat dielectric films for capacitors operating at up to 150°C. As operating temperature and frequency increase, dissipation losses in these films are reduced. This advantageous behavior is opposite to how typical high heat polymer films respond to increasing temperature and frequency. For example, Dissipation Factor Df for HTV150A films is about 0.0047 at room temperature at 100kHz. Df drops to 0.0027 when temperature increases to 150°C at the same frequency of 100kHz. For PEN films the values are 0.0074 and 0.0115, respectively. The higher losses for PEN at high temperatures limit its use to about 125°C to avoid excessive heat generation in the capacitor. Reduced losses in the dielectric film can lead to overall reduction in heat generation in the capacitors, which in turn leads to overall efficiency gain in the inverter module. Capacitors built with 3µm and 5µm metalized films pass standard electrical and life tests at 150°C for 2000 hours, as well as damp heat aging tests for 1000 hours, with low capacitance change and stable insulation resistance. Performance data and examples of metallization and capacitor building will be discussed.
