iMOTION’s digital block consists of the IRMCF3xx family of digital control ICs. These ICs include IR’s patented Motor Control Engine (MCE) that implements the complex sensor-less PMSM algorithm in hardware, thus eliminating software coding from the development process. The IRMCF3xx also features an embedded analog signal engine (ASE) that integrates all signal conditioning and conversion circuits for single-current shunt sensorless control. The Motor Control Engine executes the sensor-less field oriented control (FOC) algorithm in about 11 micro-seconds, which is the key feature that enables simultaneous control of the fan and compressor motors as well as the PFC circuits. The IRMCF311 and the IRMCF312 are currently the only single devices in their class capable of simultaneously controlling all three systems.

The IRMCF3xx also includes an application layer processor that defines the operation of the air conditioning system independently from the MCE engine that controls the fan and compressor motors. Easy-to-use tools allow the engineer to evaluate controller performance and customize the algorithm with minimal effort, so the appliance engineer can focus his efforts on application issues rather than motor control functions.

Figure 1. Motor Control Engine