Brushless DC motors (BDCM) possess higher efficiency than the conventional induction motors (IM) and thus, BDCMs have been widely used in the DC compressors. Since the conventional position sensors cannot work well in the hermetic compressors, many control method without position sensor for DC compressors have been proposed. The performance of DC compressors is improved after the proposed sensorless circuits are well studied and the speed control considering the load condition of compressors are also suggested in this paper. All the other developed starting strategy and the sensorless algorithms are also presented and digitally implemented. Finally, some experimental results are also displayed to demonstrate the proposed speed control for DC compressors.