一种三相交错并联双向传输CLLLC谐振变换器

Three-phase interleaved bidirectional CLLLC resonant converter

针对电动汽车OBC(On Board Charger)在进行充放电时,需要DC/DC变换器同时具备大容量和双向功率传输的性能,提出了一种能够双向功率传输的三相Y-Δ型交错并联结构的CLLLC型DC/DC谐振变换器。它兼顾了多相交错并联结构的大容量特性和CLLLC结构的双向功率传输能力。该结构高压侧为Y型交错并联,低压侧为Δ型交错并联,实现较小的变压器原、副边匝比,同时使各相间自动均流。对CLLLC结构在高、低压侧谐振腔不完全对称情况的增益特性进行了分析,给出了该拓扑的参数设计方法。选取了一组参数,其可以通过变频控制在高压侧得到最高两倍的电压增益。最后通过一台频率200 kHz功率1.5 kW的实验样机进行验证,证明该型拓扑结构和其参数设计方法的可行性。

For the requirements of electric vehicle OBC(On Board Charger)in charging and discharging,the DC/DC converter has large capacity and bi-directional function.A CLLLC type DC/DC resonant converter with three-phase Y-Δinterleaved parallel structure was proposed.The CLLLC structure have both large capacity characteristics of the multi staggered parallel structure and bidirectional power transmission capability.The high-voltage side of this topology is Y-type interleaving parallel connection,and the low-voltage side isΔtype interleaving parallel connection,that can realize smaller turn ratio of primary and secondary sides of transformer,and even make each phase automatically share current.Method was analyzed to get the gain characteristics of CLLLC topology in the case of asymmetric resonators at high-voltage and low-voltage side,and the parameter design method of the topology was given ether.A group of parameters was selected,which can get maximum twice gain of voltage in the high voltage side by frequency conversion control Finally,an experimental prototype working at 200 kHz frequency and 1.5 kW rated power was used to verify the feasibility of the topology and its parameter design method.