Study on new frequency conversion control system and power balance control method of dual-motor for shearer traction unit

Abstract

The drive system of shearer traction unit is affected by complex load interference and system structure, which results in the problem of unbalanced power of dual-motor of shearer traction unit. A new type of dual-motor frequency conversion control system for shearer traction unit with “common rectification and dual inverters” is designed. And a dual-motor power balance control method based on particle swarm optimization torque cross-coupled control is proposed. The new frequency conversion control system adopts a parallel structure of two inverter circuits with a common DC bus. Particle swarm optimization is used to optimize the PID control parameters of torque cross-coupling control, which solves the problem that it is difficult to gain optimal PID parameters. The control model is established using Matlab/Simulink simulation software. The proposed control method and the master-slave control method are compared by simulation. The results show that the control effect of proposed control method is better synchromization and power balance effect than the master-slave control method. The proposed control method is applied to dual-motor control of shearer traction unit for experimental verification. The results indicate that the proposed power balance control method realizes that the output torque ratio of dual-motor is between 0.9 and 1.1.

Load torque composite synchronous control of dual‐driven systems

“…Then, considering the influences of mismatch dynamics in the transmission parts such as misalignment, or wear of the gearing faces, which can lead to a significant disparity between $${K}_{g1}$$ and $${K}_{g2}$$ [14, 26], Figure 6 illustrates the $${T}_{Lsync}$$, $${i}_{qsync}$$, and $${\theta }_{sync}$$ when $$\epsilon $$ for $${K}_{g1} \ne {K}_{g2}$$ is set to $$5\% $$, $$20\% $$, and $$50\% $$, respectively. Contrary to the results in Figures 4 and 5, $${T}_{Lsync}$$ and $${i}_{qsync}$$ when $${K}_{g1} \ne {K}_{g2}$$ show similar trends.…”

“…In practice, the speed master‐master control (MMC) structure, illustrated in Figure 1b, is commonly utilized, where dual axes share identical speed reference and controller $${G}_S$$ to drive the load simultaneously [26]. However, the dynamics of parallel axes may be different due to corrosion, deformation, or inadequate maintenance [14, 25, 31]. Then, through an inner complex coupling relationship, these mismatch dynamics will result in the emergence of load torque synchronous error as $$$$\begin{equation}{T}_{Lsync} = {T}_{L2} - {T}_{L1}\end{equation}$$$$…”

“…For this application, the adaptability of the composite control scheme needs further analysis. By integrating the lump disturbances in (7) with the decoupling control design in (14), we have…”

“…In addition, according to the motor motion equation, the load torque can be reflected in the torque current. Therefore, the synchronization of torque currents has also been considered to equally attain load torque synchronization [14, 26, 27]. Similarly, the literature [28] synchronizes the electromagnetic torques of both axes, which is proportional to the torque current for either axis.…”

“…The utilization of the cor-rection unit within the CCC scheme is intended to shorten the adjusting time [13]. The power balance in a shearer traction unit is improved by incorporating the particle swarm optimization algorithm to determine the CCC gain [14]. Taking the potential model uncertainties into account, the sliding mode algorithm is incorporated into the conventional CCC structure [15].…”