POWER CIRCUIT TOPOLOGY FOR SINGLE-PHASE BATTERY ENERGY STORAGE SYSTEM CONSIDERING BATTERY LIFE AND THE METHOD

摘要

According to the present invention, a single-phase BESS power conversion device for extending the life of a battery includes: a boost converter which is connected to a battery cell unit, raises the DC voltage charged to the battery cell unit in a charging mode of the battery cell unit, and outputs the raised DC voltage; a bypass switch which is connected to the battery cell unit in series, connected to the boost converter in parallel, and switched on in a discharging mode of the battery cell unit to allow the DC voltage charged in the battery cell unit to pass through; and a PWM inverter unit which supplies power to a load using the DC voltage passing through the bypass switch correspondingly to a PWM signal, converts the power applied by system power, and outputs the result to the boost converter. According to the present invention, the present invention guarantees a high charging voltage by including a boost converter and a bypass switch in a battery cell and turning off the bypass switch (SWDC) in a charging mode of a battery and at the same time stably supplies battery charging voltage/current to the battery without ripples, thereby being able to extend the life of the battery.