An E175 Captain reported electrical failures and loss of navigation equipment and a return to departure airport. The reporter stated these failures had previously occurred on this same aircraft.

Narrative

This report goes over the event that took place that ended in a landing at ZZZ.Several Failures associated with 3 major root causes.AC Bus 1 offDC Bus 1 off AVNX MAU 1B FailAfter the 14 to 16 EICAS messages I called for all three checklists while I attempted to speak with ATC. At first my com worked and I was able to [advise ATC] and let them know that we were returning to ZZZ; shortly after that I lost left side MCDU (Multipurpose Control Display Unit) and com 1. I also lost all navigation aids so I had to fly raw data while FO was running checklist and communicating with ATC. We conducted the checks; briefed the flight attendants. We were getting vectored for the return to ZZZ. We were getting to land on XXR. We were in and out of IMC. Luckily we were able to clear that and get the visual that we needed to be able to land. The tower was giving us vectors before we could see the runway. We had a good normal landing and after we cleared the runway we came to a stop and the operations vehicles did a 360 to inspect the aircraft and found nothing wrong. But; I had no nose wheel steering so we shut down the engines and we got towed to the gate.This very same electrical anomaly and several failures also occurred on a previous date on this very same aircraft. It is obvious that there is something wrong with this aircraft's MAUs (Modular Avionics Unit) and it needs to be looked into severely. This is a major safety hazard. In my opinion this aircraft should be taken off-line; not just reset and stuck back out on the line. Suggestion: Do not return AC to service before full repair.