Control Stability and NVH Improvements of the Variable Displacement Swashplate Compressor

As progress is made to reduce the NVH (Noise and Vibration Harshness) levels of the engine, the noise and vibration generated by the A/C compressor becomes more pronounced to the occupants. Compressor designs that offer Best-in-Class NVH levels are being favored by vehicle manufacturers; however, the product offering must also incorporate technology such as continuous operation, high-speed capability, optimized package size, and lower weight that allows its application to smaller power-trains.

The continuously variable displacement compressor satisfies the requirement for continuous operation by controlling the displacement to match the A/C system demand. The new technology offers improvements in speed capability; NVH and displacement control, and is steadily replacing the older “wobble-plate” variable displacement compressors, that were first introduced in 1984. This paper will explain the enhancements for NVH, control stability, and high-speed operation incorporated into the swashplate variable design.