IPT Fact Sheet Series: No. 2 Magnetic Circuits for Powering Electric Vehicles
IPT Fact Sheet Series: No. 2 Magnetic Circuits for Powering Electric Vehicles
复制标题
IPT 情况说明书系列：为电动汽车提供动力的 2 号磁路
DOI：
--
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
D. Muller
中科院分区：
文献类型：
--
作者：
M. Bukshtab;Amit S. Paranjape;M. Friedman;D. Muller
简介 用于电动汽车电池原位充电的感应电力传输 (IPT) 系统因其无线且无需插入而受到关注。这些系统使用两个无线垫（一个位于车辆底部，另一个位于车辆下方的路面），它们彼此磁耦合。这种无线功率传输在与具有高本机品质因数 (QL) 的线圈或多个线圈谐振下使用感应耦合。耦合是磁路和电路的几何特性：更好的焊盘根据其设计实现耦合，而不良的设计永远无法得到充分补偿，而是不可避免地导致不良的 IPT 系统。早期的商业设计是在 90 年代开发的，并在过去 20 年中得到了改进。在学术文献中已知这种感应耦合与强耦合磁共振相同。为了以最小的场泄漏实现高效充电，汽车必须停放或定位，以便两个充电垫彼此相对靠近。在这些条件下，识别系统允许两个垫子相互通信，最终地面上的垫子被“点燃”，能量从地面垫子转移到车载垫子，然后再传递到电池。当电池充电时，系统断开连接；地面垫和车辆垫都关闭。在更复杂的情况下，充电器还可以将电力从汽车传输到接地板，然后再传输回公用设施，并且下面描述的所有此类系统都可以是双向的；然而，这里不会明确讨论此操作。仅当同时满足以下几个条件时，才能通过 IPT 进行无线充电： 充电垫必须彼此兼容 充电垫必须以相同的标称频率运行 汽车的位置必须使车载充电垫处于该充电垫对允许的相对 x、y、z 误差范围内 两个充电垫之间的通信协议必须兼容 两个充电垫的额定功率和连接必须设计为兼容且具有相似的额定值 – 100kW 总线初级充电器不能与 2kW 二次汽车电池连接一起使用，以实现高效率和低场发射，尽管如果在设计阶段考虑到这一点，20kW 主系统可能能够使用相同的 2kW 二次电池获得良好的结果。
Introduction Inductive Power Transfer (IPT) systems for charging EV Batteries in-situ are gaining attention as they are wireless and do not have to be plugged in. These systems use two wireless pads – one on the underside of the vehicle and the other on the road surface underneath the vehicle – that are magnetically coupled to each other. This wireless power transfer uses inductive coupling under resonance with coils or multiples of coils with high native quality factor (QL). The coupling is a geometrical property of the magnetic and electrical circuits: better pads achieve coupling depending on their design and a poor design can never be adequately compensated but leads inexorably to a poor IPT system. Early commercial designs were developed in the 90’s and have been improved over the past 20 years. This inductive coupling is known in the academic literature to be identical to strongly coupled magnetic resonance. For efficient charging with minimal field leakage the car must be parked or positioned so that the two pads are in relatively close proximity to each other. Under these conditions a recognition system allows the two pads to communicate with each other such that ultimately the pad on the ground is ‘fired up’ and energy is transferred from the ground pad to the on-vehicle pad and thence to the battery. When the battery is charged the system disconnects; both the ground pad and the vehicle pad are shut down. In more complex situations the charger can also transfer power from the car to the ground pad and back to the utility and all such systems described following can be made bidirectional; however this action will not be explicitly discussed here. Wireless charging via IPT can only occur if several conditions are met simultaneously: The pads must be compatible with each other The pads must operate at the same nominal frequency The position of the car must have the onvehicle pad within the relative x, y, z, error that is allowable for this pad pair The communications protocol must be compatible between the two pads The power ratings and connections of the two pads must be designed to be compatible and at similar rating – a 100kW bus primary charger cannot be used with a 2kW secondary car battery connection with an expectation of high efficiency and low field emissions, although a 20kW primary system may be able to achieve good results with the same 2kW secondary if this is considered at the design stage.