Why the AC compressor cut out when the engine running more than 1000 RPM either the car is static or moving?

I live in hot climate country Malaysia. The problem with my car AC system is, there is no cooling when the car running in high speed. In other words there is no cooling when the car running in higher RPM (more than 1000 RPM). The same problem still occurs when the car is not moving or static. I did stop the car, with the engine run, switch on the AC and the AC is OK and I feel the cool. Just when I ram up the engine exceeding more 1000 RPM, after a few while there was no cooling. I looked at the compressor and noticed that the magnetic cluth disengaged. I had replaced strainer drier, air filter and expansion valve before but the problem still happen. During the engine running with 1000 RPM hi side pressure is 155 PSIG and low side is 26 PSIG. I dont think that the compressor cut out due to the Hi/LOw pressure switch cut out.