Energy saving in DC/AC drive compressors & pumps using ZCTF PWM inverter: A study

Despite past technologies which were using Steam turbine or Gas turbines to drive industrial compressors, Today, most compressors used in refrigeration and gas compression purposes are using Induction motors with PWM (Pulse Width Modulation) Inverters as a drive or DC motors in heavy industrial loads with DC/DC converters installed. This is due to the fact that these technologies help us to deduct energy consumption and C0₂ emissions which are known as important environmental issues in today's world. As a brief, one of the main advantages gained by the use of these is the fact that the compressors can supply just the exact amount of cooling required. Supplying cooling at a higher level will be avoided and energy will be saved automatically. In this paper we will introduce new application of Zero Current PWM forward inverter in compressors with DC drives, presenting a study on how using VSD drive technology or DC-based drive to save energy in compressor and pumping applications. Affects of usages of PWM Inverters/DC-DC converters on lubrication; cooling and parallel compressors usages will be discussed. In the proposed DC converter, zero current switching condition is achieved for the switches while the control circuit still remains PWM to act as a DC drive. The proposed AC inverter / DC Converter is analysed. Simulation results are presented which confirm the theoretical analysis.