Comparison between model reference observer and reduced order observer of PMSM torque

Abstract

The load torque disturbance influences the performance of permanent magnet synchronous motor speed control. Therefore, to compensate this problem, this paper designed a model reference torque observer based on Popovsuper-stability theory. This observer uses off-line calculation to obtain the model parameters and PI calculation of the speed model error to get the load torque. This structure is simple and easy to implement for speed control compensation. The compare of this observer and a reduced order torque observer is studied by simulation. The results show that the model reference observer designed this paper has better performance in convergence, noise immunity and observation accuracy, and is more suitable for speed control compensation.

PMSMs Torque Estimation Using Pulsating HF Current Injection

“…Indirect estimation methods include methods based on the electric power and rotor speed [10], observer based methods [11]- [16] (e.g. sliding mode observers [11], model reference adaptive systems [12]- [13], model reference observers and reduced order observers [14], recursive least square parameters estimation [15] or affine projection algorithms parameters estimation [16] being the most extended) or methods requiring additional sensors, e.g. giant magnetoresistance effect (GMR) based methods [17].…”

“…4 shows the signal processing required for torque estimation. Inputs to the torque estimation block are the output voltage of the HF resonant (2) Pulsating q-axis HF current injection (14) L qHF estimation (19)- (20) Differential (14) and the injected fundamental current i dqsf r* , see Fig. 3.…”

“…Daxis inductance (L d ) can be estimated by injecting a pulsating d-axis HF current as shown in (7)-(13). Q-axis inductance (L q ) can be estimated by injecting a pulsating q-axis HF current(14)-(20). T rel estimation using pulsating HF current injection is schematically shown inFig.…”

Comparative Analysis of High Frequency Signal Injection Based Torque Estimation Methods for SPMSM, IPMSM and SynRM

“…Torque estimation methods can be roughly separated into (a) methods based on the torque equation [21,22] and (b) indirect estimation methods [23][24][25][26][27][28][29][30][31]. The first type can use the General Torque Equation (GTE) assuming constant motor parameters [21], Flux estimation with Compensation Scheme (FCS) where dq-flux linkage is estimated by the measurement of stator voltage, currents and rotor position [21] or look-up-tables, which are used to adjust the machine parameters according to machine operating conditions [22].…”

“…The first type can use the General Torque Equation (GTE) assuming constant motor parameters [21], Flux estimation with Compensation Scheme (FCS) where dq-flux linkage is estimated by the measurement of stator voltage, currents and rotor position [21] or look-up-tables, which are used to adjust the machine parameters according to machine operating conditions [22]. A large number on indirect torque estimation methods have been proposed, which go from a simple power balance with known electric power and rotor speed [23], observer based methods [24][25][26][27][28][29] (e.g., sliding mode observers [24], model reference adaptive systems [25,26], model reference observers, reduced order observers [27], recursive least square parameters estimation [28] or affine projection algorithms parameters estimation [29]), methods requiring additional sensors, e.g., giant magnetoresistance effect (GMR) based methods [30], or neural networks based methods [31]. All these methods [21][22][23][24][25][26][27][28][29][30][31] require previous knowledge of certain machine parameters (e.g., resistances or inductances) and/or its operating condition (e.g., temperature).…”