A system and method for controlling gas surges in compressors powered by electric motors. An adjustable speed drive (ASD) incorporating a microprocessor powered by a three-phase source of electricity controls the electric motor which drives the compressor. A bypass valve is inserted between the gas input of the compressor and the gas discharge. The bypass valve opens in response to signals from the ASD which detects gas surges by analyzing a stored surge map which plots a surge line and a related discretionary control line based on the power and speed of the motor. When the operating point of the motor crosses the control line, the ASD causes the bypass valve to open.