Add MotorDrive package

[mingzhe37]

Hi Dr. Hu @JayHuLBL, could you please create a branch for the MotorDrive package described in this issue when you get a chance?

This issue is to add the induction motor and motor-driven building facility models to Buildings.Electrical.AC.ThreePhasesBalanced.Loads and two interface models to Buildings.Electrical.Interfaces package, including the following:

• Buildings.Electrical.AC.ThreePhasesBalanced.Loads.MotorDrive: 　InductionMotors: 　　SquirrelCage 　　SquirrelCageDrive 　　Examples: 　　　SquirrelCage 　　　SquirrelCageDrive 　　BaseClasses: 　　　MotorMachineInterface 　　　Validation: 　　　　MotorMachineInterface 　ThermoFluid: 　　Chiller 　　HeatPump 　　Pump 　　Examples: 　　　Chiller 　　　HeatPump 　　　Pump 　Coupled: 　　Chiller 　　HeatPump 　　Pump 　　Examples: 　　　Chiller 　　　HeatPump 　　　Pump
• Buildings.Electrical.Interfaces 　PartialOnePort 　PartialBaseOnePort

Model Descriptions These models include squirrel-type induction motor models, pump/heat pump/chiller models with a mechanical interface, and motor coupled pump/heat pump/chiller models. Besides, two interface models, PartialOnePort and PartialBaseOnePort, are added to be used in motor related models. This work is part of the GED project.

Please let me konw if you have any questions, thank you!

[JayHuLBL]

@mingzhe37 I just created branch issue2948_MotorDrive for this issue.

[mingzhe37]

@JayHuLBL Many thanks! I will work on this branch.