As o.m. already wrote, getting a new passport would not help at all but he or she forgot the most important reason: Your previous applications have all been recorded in a database so any other Schengen consulate (not only in your current country of residence, and not only from Germany) can and will very easily find out about them. Changing your passport without credible reason might actually make your application look even worse as it signals an intent to deceive.
Beyond that, there is nothing stopping you from applying again and in theory previous refusals do not legally lead to automatic refusal of a new application but if your plans and your situation haven't changed, there is no reason to expect a different outcome. Furthermore, if you have offered a different purpose for the trip in your last applications (how would you expect a new application to succeed otherwise?), changing your story all the time and collecting refusals do not make you look like a reliable applicant to the consulate.
Also, if you have already got three refusals and a failed appeal, you obviously have very weak applications. You might need to get help from a real lawyer and work very hard to improve your situation to even have a fighting chance at getting a visa, simple tricks like renewing a passport are not going to help.