Model-Based Direct Flux Vector Control of Permanent-Magnet Synchronous Motor Drives

Abstract

This paper proposes a direct flux vector control strategy with no need for regulators tuning, suitable for Permanent Magnet (PM) Synchronous Machine drives. The controller operates in stator flux coordinates, and calculates the inverter reference voltages in a model-based fashion, taking advantage of a novel equation for the explicit evaluation of the torque angle error. The inverter current and voltage limits are exploited in a parameter-independent way. The method segregates the machine parameters into a single block, so to make it very easy to switch from one machine to another. Experimental results are reported for a PM-assisted synchronous reluctance motor drive example, characterized by significant saturation and cross-saturation. State of the art control techniques such as current vector control and nonmodel-based direct flux vector control are also considered, for the sake of comparison, in simulations and experiments. I.

Sensorless Direct Torque Control of Surface-Mounted Permanent Magnet Synchronous Motors with Nonlinear Kalman Filtering

“…Among them, field oriented control (FOC) for SPMSM drives has reached industrial application maturity. FOC requires coordinate transforms and space-vector pulse width modulation (SVPWM), through which the flux and torque of AC machines are controlled independently [1][2][3][4][5]. In order to eliminate these requirements, direct torque control (DTC) was proposed as a powerful alternative [6,7].…”

A Linear Quadratic Regulator-Based Optimal Direct Thrust Force Control of Linear Permanent-Magnet Synchronous Motor

“…These studies are also analogously valid for linear PMSMs. The relation between the electromagnetic thrust force and the load angle for a surface-mount linear PMSM is given as [13]: (12) The studies in [31] and [32] detail the linearization of the nonlinear relation between the load angle and torque for interior PMSMs. The linearization methods discussed in [31]- [32] can also be applied to surface-mount linear PMSM by linearizing (12) using Taylor's expansion at load angle as:…”

“…According to (12) the maximum force occurs when is controlled at radians. However a closer inspection of (12) suggests that, when is kept constant at (as explained previously), then for a machine with small value of the polepitch and low stator inductance , the rated maximum force of the linear PMSM is typically achieved at values of much smaller than and therefore, has a small operational range of .…”

“…This justifies the assumption that for the small range of values for . Therefore, using (12) and (13), the linearization coefficient for the prototype linear PMSM with stator flux is set to can be approximated as:…”

Optimal torque control of synchronous motor drives: Plug-and-play method

“…Instead of current or flux linkage control, direct flux vector control can be used [17], [21]- [23]. In this method, the optimal references in the field-weakening region are easier to solve, but still the MTPA trajectory and the MTPV limit have to be implemented.…”