Tungsten wire array implosions driven by 1 MA to 4 MA current were experimentally investigated. X-ray radiation power was improved through load parameters optimization,electrode structure improvement and well control of initial array conditions. The maximum powers of 5.3±1.0 TW and 5.6±1.1 TW, the highest at the 3 MA to 4 MA current level up to now, were measured in the single array and the double array implosions, respectively.