新型無接觸電流傳感器HEV及可再生能源應用

　　集成磁集中器（IMC）霍爾效應傳感器特別適用于電池電流監測、太陽能逆變器和驅動混合電動汽車和電動車輛牽引電機的功率逆變器。本文解釋了IMC電流傳感器的設計，它們如何執行，以及它們是如何在這些應用中應用的。

　　傳統上，電流是通過電阻分流器、磁傳感器或電流互感器來測量的。雖然電阻分流器是流行的，但磁傳感器在系統級提供許多優點。例如，非接觸式磁傳感器不需要電流導體和傳感器之間的電流隔離。電阻式分流器將電能轉換為熱能，在某些應用中會產生熱管理費用和麻煩。磁傳感器避免了這些問題。此外，CMOS霍爾效應磁傳感器可以集成高級功能以提供高電平輸出信號。復雜的磁傳感器包含可編程存儲器，甚至微控制器邏輯，允許完全定制校準輸出。甚至可以實現標準接口，簡化與其他電路的通信。

　　不像電流互感器中的線圈（電流互感器），它測量磁通的時間導數，霍爾效應傳感器產生一個與磁通密度本身成比例的信號。這使得測量直流和交流電流實用。

　　The widespread use of electronics in automotive applications， renewable power conversion （solar and wind power）， power supplies， motor control， and overload protection demands that engineers use more effective current measurement techniques. These applications benefit from robust， reliable， isolated， high-speed， and low-cost current measurement techniques provided by IMC sensors.

　　These novel， contactless current sensors consist of an integrated CMOS Hall effect sensor covered by an additional thin， ferromagnetic layer on its surface. This IMC layer acts as a magnetic flux concentrator， providing a high magnetic gain that increases the sensor‘s signal-to-noise ratio. The sensor is particularly appropriate for DC and AC current measurement. Such measurements are characterized by the need for ohmic isolation， very low insertion loss， fast response， small package size， and low assembly costs. Typically， current sensors are found in applications such as battery current monitoring， solar power inverters， and power inverters that drive traction motors in EVs （electric vehicles）， and HEVs （hybrid electric vehicles）。 There is no upper limit to the level of measurable current of IMC sensors， since their output level depends only on the conductor’s size and its distance from the sensor.