Summary for: SMGridCalculator_DQ < handle

Class summary

SMGridCalculator_DQ DQ-grid calculator for synchronous machines.

Computes a grid of (id, iq) pairs, using static analysis and ignoring damping effects.

calculator = SMGridCalculator_DQ(motor, key, val, …) with any of the following:

  • Jmax_axis : maximum current density per axis. Default 15 Arms/mm^2.

  • nbase : speed (rpm) to compute results on. Default 3000.

  • Nsamples : number of steps to use. Default 33.

  • periodicity : a fraction of full period to analyse. E.g. 6 = step from 0 to 60 el. degrees. Default 6.

  • ids_pu : per-unit current values on d-axis. See below. Default -1:(1/4):(1/4).

  • iqs_pu : per-unit current values on q-axis. The actual currents for the grid are [id, iq] = meshgrid(ids_pu, iqs_pu) * Imax, where Imax = Jmax_axis * conductor_area_per_turn_and_coil. Default linspace(0, 1, 5)

Important methods:

  • this.compute_all : compute grid.

  • grid = this.get_results(args) : get NTGridDQ

Note: The NTGridDQ class uses the MTPAinterpolant class to obtain the (id,iq) currents corresponding to the desired (T,rpm) pair. The interpolant class only searches the computed (id,iq) range. In particular, numerical noise can often cause e.g. T(id~=0, iq=0) to be slightly above zero, which can occasionally lead to very large id«0 immediately once the field weakening region is entered. A simple, often sufficient, fix is to simulate an iq range starting from a small negative pu value, e.g. 1e-2.

Properties

.SMGridCalculator_DQ/demag_computation_arguments is a property.

.SMGridCalculator_DQ/grid is a property.

.SMGridCalculator_DQ/problem is a property.

Methods

Class methods are listed below. Inherited methods are not included.

.SMGridCalculator_DQ/compute_all is a function.

this = compute_all(this)

.SMGridCalculator_DQ/compute_point is a function.

solution = compute_point(this, ~)

.get_results Get computed NTGridDQ.

grid = get_results(this, key, val)

  • see help NTGridDQ for key, value pairs.

.— help for SMGridCalculator_DQ/maximum_torque_at_speed —

SMGridCalculator_DQ/maximum_torque_at_speed is an undocumented builtin SMGridCalculator_DQ method.

.SMGridCalculator_DQ/parse_problem_circuits is a function.

parse_problem_circuits(this, N)

.saving torque

There = sim_compute_torque(problem, pars, ‘static’);

.SMGridCalculator_DQ/setup_all is a function.

this = setup_all(this, motor, varargin)

.SMGridCalculator_DQ/setup_point is a function.

this = setup_point(this, k)