Development of High Frequency Response Battery and Enhancement of Power Density for Inverter 2021-01-0753
We propose low inductance batteries and enhance power density for a inverter. Conventionally, the capacitors are used for smoothing ripple of the inverter. The low inductance battery which responds at carrier frequency of inverter can reduce the capacity of the smoothing capacitors and enable to enhance power density for the inverter.
For reducing the inductance, it is necessary to separately understand the impact of electrochemical reaction under wide range of assumed conditions and structural reaction on frequency characteristics. Furthermore, it is also necessary to design the low inductance batteries based on combining the both of characteristics. However, there are no study focusing on modeling by combining such different domains. Therefore, we made original inductance model inside battery considering frequency characteristics among all materials and structural influence with electromagnetic field analysis simulator. Then, we compared obtained simulated values with actual battery. As a results, we found that both values were corresponding each other and it is possible to design the low inductance battery with this approach.
Finally, we verified smoothing effect for inverter output using our low inductance battery module. We conducted smoothing test by high frequency current as input into the battery module. We confirmed that battery voltage fluctuation was reduced less than 5% at an current condition which voltage fluctuation was more than 5% for normal batteries. As a results we have shown it is possible to reduce smoothing capacitors by using low inductance batteries.