Sensorless Energy Conservation Control for Permanent Magnet Synchronous Motors Based on a Novel Hybrid Observer Applied in Coal Conveyer Systems

Abstract

A large number of permanent magnet synchronous motors (PMSMs) are used to drive coal conveyer belts in coal enterprises. Sensorless energy conservation control has important economic value for these enterprises. The key problem of sensorless energy conservation control for PMSMs is how to decompose the stator current through estimating the rotor position and speed accurately. Then a double closed loop control for stator current and speed is formed to make the stator current drive the motor as an entire torque current. In this paper, the proposed startup estimation algorithm can utilize the current model of PMSM as reference model to estimate the rotor speed and position in the startup stages. It is not dependent on the back electromotive force (EMF) which is used by the general estimation algorithm. However, the resistance will change with the temperature shift of stator windings, and these changes will cause the reference current model to be inaccurate and influence the rotor speed and position estimation precision. Thus, startup estimation algorithm switches to the proposed operation estimation algorithm which is based on the robust sliding mode theory and is not dependent on the motor parameters. The advantages of startup estimation algorithm and operation estimation algorithm are combined to form a hybrid observer. This hybrid observer realizes the accurate estimation of the rotor speed and position from start-up to operation. The stator current is precisely decomposed. The excitation current is controlled to 0. Meanwhile, the double closed-loop control of current and speed is achieved. The stator current is as entire torque current to drive motor. The closed-loop control, which is based on the proposed rotor position and speed estimation algorithm, achieve the most efficient conversion of electrical energy.

Model-Free Control Using Improved Smoothing Extended State Observer and Super-Twisting Nonlinear Sliding Mode Control for PMSM Drives

“…The mechanical torque equation and dynamic equation of PMSM are expressed in (1) and (2), respectively. The linear ultra-local model of the PMSM is expressed in (3) and the system track error is denoted in (4) [25][26][27].…”

“…As the permanent magnet synchronous motor (PMSM) has low energy consumption, reliable operation, and simple structure, it has been widely used in coal conveyor systems [1], mine traction electric locomotives [2], electric vehicles [3,4], water pumping applications [5] and so on. However, the PMSM dynamic model has the characteristics of coupling and is multivariable.…”

Energies and Its Worldwide Research

“…Figure 22a shows 15 nodes highlighted by their relations in the community. The three largest nodes correspond to two research articles that promote improvements in synchronous motors [82,83], and the third document is the promotion of a Special Issue that covers permanent magnet synchronous machines and the electrical systems to which they are connected in different areas of application [84]:…”

“…• "Investigation of a Novel 24-Slot/14-Pole Six-Phase Fault-Tolerant Modular Permanent-Magnet In-Wheel Motor for Electric Vehicles" with 38 citations [82]. • "Sensorless energy conservation control for permanent magnet synchronous motors based on a novel hybrid observer applied in coal conveyer systems" with one citation [83]. • "Permanent magnet synchronous machines" without citations [84].…”

“…The identification of the short circuit fault occurs by analyzing the time domain of the non-linear transfer model. Shun Li and Xinxiu Zhou (2018) proposed a reference model to estimate the rotor speed and position in the starting stages in PMSM to drive coal conveyors [83]. They use a hybrid observer (start-up estimation algorithm and operation estimation algorithm) for accurate estimation of rotor speed and position from start-up to operation.…”