Modeling interior permanent magnet synchronous machines considering permeability of rotor

Patent metadata

Field	Value
Publication number	US-11366944-B2
Application number	US-202017000551-A
Country	US
Kind code	B2
Filing date	Aug 24, 2020
Priority date	Aug 24, 2020
Publication date	Jun 21, 2022
Grant date	Jun 21, 2022

Abstract

A system for evaluating an electromagnetic performance of a permanent magnet (PM) motor. Parameters update an electromagnetic analytical (EA) model. Each component of the PM motor is associated with regions, and assumptions of the EA model include a relative permeability of regions associated with a rotor core modeled as finite. Calculate a general solution to a governing equation to each region which include unknown coefficients to be determined. Define a set of boundary and interface (B&I) conditions for two neighboring regions, each B&I condition is defined through a set of Maxwell equations using the two neighboring regions sets of assumptions, geometries of the PM motor and electrical and magnetic properties associated with the two neighboring regions. All the unknown coefficients in the general solutions in all regions are solved with a linear system of equations obtained from the B&I conditions between the regions, to solve for a magnetic vector potential.

First claim

What is claimed is:

1. A system for designing an evaluation of an electromagnetic performance of a permanent magnet (PM) motor, comprising:
a transceiver to accept parameters for an electromagnetic analysis;
a hardware processor in communication with the transceiver and the PM motor, to execute steps of an electromagnetic analytical (EA) model of the PM motor, the steps of the EA model includes
update the EA model with the parameters, each component of the PM motor is associated with assumptions including some assumptions with a relative permeability of regions associated with a rotor core modeled as finite;
calculate a general solution to a governing equation to each region of the regions of the PM motor that include unknown coefficients to be determined, based on each region having a set of assumptions, geometry of the PM motor and electrical and magnetic properties of a component of the PM motor, and identify a set of boundary and interface conditions for two neighboring regions of the regions, along with an additional boundary and interface condition between a barrier region and a neighboring pole-piece region that have different permeability values, such that the general solutions to the governing equations of each region including the neighboring regions of the regions, the barrier region, and the neighboring pole-piece region are matched at the set of boundary and interfaces and the additional boundary and interface condition of the barrier region and the neighboring pole-piece region;
calculate all the unknown coefficients in the general solutions in all regions of the PM motor based on solving a linear system of equations obtained from the boundary conditions between the regions, to solve for a magnetic vector potential for the PM motor;
evaluate the electromagnetic performance of the PM motor based on the magnetic vector potential for the PM motor; and
generate one or more type of command actions according to the evaluation of the electromagnetic performance of the PM motor and output the one or more type of command actions to a controller of the PM motor.

2. The system of claim 1 , wherein the updating of the EA model with the parameters includes updating a geometry of the PM motor and an electrical and magnetic properties for each component of the PM motor, such that each component is associated with regions of the PM motor.

3. The system of claim 1 , wherein each boundary and interface condition is defined on a basis through a set of Maxwell equations using the two neighboring regions sets of assumptions, geometries of the PM motor and electrical and magnetic properties associated with the two neighboring regions, and also identify relationships of the unknown coefficients in the general solutions of the two neighboring regions.

4. The system of claim 1 , wherein if the evaluation of the electromagnetic performance of the PM motor is below the operation threshold, one or more type of command actions are generated by the hardware processor and outputted to the controller of the PM motor, and wherein the controller receives the one or more types of command actions via an input interface, and based upon the received one or more type of command actions, the PM motor is either turned off, or continues to operate, and if the evaluation of the electromagnetic performance of the PM motor is above the operation threshold, no type of command action is generated.

5. The system of claim 1 , wherein the one or more types command actions are associated with an alert including one or a combination of an imminent pending failure of the PM motor, a maintenance action to the PM motor, a design action to the PM motor or an action associated with one or more components of the PM s motor associated with performance or maintenance.

6. The system of claim 1 , wherein the magnetic vector potential is used for predicting a flux linkage, such that the flux linkage is based on a magnetic flux that is a product of a magnetic flux density times a perpendicular area that the magnetic flux penetrates.

7. A system for designing an evaluation of an electromagnetic performance of a permanent magnet (PM) motor, comprising:
a transceiver to accept parameters for an electromagnetic analysis;
a hardware processor in communication with the transceiver and the PM motor, to execute steps of an electromagnetic analytical (EA) model of the PM motor, the steps of the EA model includes
update the EA model by inputting the parameters which updates a geometry of the PM motor and an electrical and magnetic properties for each component of the PM motor, such that each component is associated with regions of the PM motor, and assumptions of the EA model include some assumptions with a relative permeability of regions associated with a rotor core modeled as finite;
calculate a general solution to a governing equation to each region of the regions of the PM motor that include unknown coefficients to be determined, based on each region having a set of assumptions, geometry of the PM motor and electrical and magnetic properties of a component of the PM motor;
identifying a set of boundary and interface conditions for two neighboring regions of the regions, each boundary and interface condition is defined on a basis through a set of Maxwell equations using the two neighboring regions sets of assumptions, geometries of the PM motor and electrical and magnetic properties associated with the two neighboring regions, and also identify relationships of the unknown coefficients in the general solutions of the two neighboring regions,
wherein an additional boundary and interface condition between a barrier region and a neighboring pole-piece region have different permeability values, such that the general solutions to the governing equations of each region including the neighboring regions of the regions, the barrier region, and the neighboring pole-piece region are matched at the set of boundary and interfaces and the additional boundary and interface condition of the barrier region and the neighboring pole-piece region;
calculate all the unknown coefficients in the general solutions in all regions of the PM motor based on solving a linear system of equations obtained from the boundary conditions between the regions, to solve for a magnetic vector potential for the PM motor, which is used for evaluating the electromagnetic performance of the PM motor; and
generate one or more type of command actions according to the evaluation of the electromagnetic performance of the PM motor and output the one or more type of command actions to a controller of the PM motor.

8. The system of claim 7 , wherein the assumptions include one or a combination of: (a) a relative permeability of steel cores of a stator and a rotor of the PM motor are infinite; (b) a relative permeability of a rotor bridge of the PM motor is constant; (c) the permanent magnets have a same permeability as aft which is equal to one; (d) eddy-current effects are neglected; (e) end effects along a z-axis direction along the rotational axis are neglected; or (f) a structure of the stator and the rotor of the PM mother have radial sides.

9. The system of claim 7 , wherein the regions include: region I, a rotor core region; region II, a permanent magnet (PM) region; region III, j-th barrier regions; region VI, j-th pole-piece regions; region V, air-gap regions; region VI, ith slot- opening regions; region VII, i-th bottom slot regions; and region VIII, i-th top slot regions, wherein the regions I, II, and V have periodic shapes.

10. The system of claim 7 , wherein the magnetic vector potential is used for predicting a flux linkage, such that the flux linkage is based on a magnetic flux that is a product of a magne

Assignees

• Mitsubishi Electric Res Laboratories Inc

Inventors

• Wang Bingnan
• Shin Kyung-Hun

Classifications

• G06F17/13

  Differential equations (using digital differential analysers G06F7/64) · CPC title

• G06F30/20 Primary

  Design optimisation, verification or simulation (optimisation, verification or simulation of circuit designs G06F30/30) · CPC title

• H02K1/276

  Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM] · CPC title

• H02K21/16 Primary

  having annular armature cores with salient poles (with homopolar co-operation H02K21/20) · CPC title

• H02K2213/03

  Machines characterised by numerical values, ranges, mathematical expressions or similar information · CPC title