If the PS1 has a utility port in the back, get a plug-mod. It's like a modchip, but it just plus in the back. It does more than a normal modchip too to since it has its own OS and memory for saving cheats and it can play videos and launch executables directly from disk. It's great for homebrew.
If not, you can use a GameShark (or the PSX-Xchange disk) to swap disks along with a spring to keep the cover button held down. These disks will stop the motor when its time to swap, so no damage to your system.
As an aside, every computer that exists today can emulate PS1 at full speed with upscaling using EPSXE; including Android phones. If that doesn't work because your computer is 25+ years old, Bleem and Virtual Game Station run on a 180mhz Pentium.
Either way, don't try the swap trick. It doesn't work (at all for me, but not reliably for anyone) and it will damage your system.