Bartlomiej Wicher

Static and dynamic ergonomic corrects of torque controlled in bicycle ergometer

In this paper various methods of ergonomics improvement in electric bicycle pedaling are discussed. The main goal is to control an average amperage of generator powered by a cyclist, but considering the unsteadiness of human legs torque vs. angular position of the support. In the paper, four different approaches for generating the current reference trajectory are compared - two of them use only position signal, and the next two use also velocity signal in the ergonomic improvements calculations.

Dynamic model and analysis of distributed control system algorithms of three wheel vehicle

The article presents a synthesis of tricycle model with a unique concept of electric power. Conventional, mechanical coupling of a drive wheel with pedals has been replaced by the use of generator and independent motor drives. The essence of the model includes a distributed form of control system. The paper shows the genesis of the project and the motivation that results from the need to verify the condition of the vehicle in operation for a given control structure and parametres before target implementation. For the components of the model: mechanics (kinematics and dynamics), motor drives and central control system relevant mathematical equations and the corresponding signal flow block diagrams were presented. Changes effect in the control structure and in parameters on the dynamic processes occurring in the model were presented for the testing extortion that emulates human driver behavior. The analysis of simulation results were supplemented by quality indicators of the system performance important from a practical point of view. Conclusions and proposes of further research directions were presented.

Speed calculation methods in electrical drive with non-ideal position sensor

In this paper three methods of electric motor angular speed calculation are compared. The source of the measurement signal is a 14-bit absolute encoder. The authors compared the well-known classic methods M with more advanced approaches. First of the complex methods is based on utilization of phase loop lock system in an estimation process using on-line system model. The third method discussed in the paper is focused on application of Chebyshev filter. Short description of all of the mentioned method is followed by simulation and experimental results. The results are presented on an instance of permanent magnet synchronous motor drive, with both speed controller and speed calculation algorithms implemented in a digital signal processor system.

Control of electromechanical object with backlash and elasticity within interconnection between motor and load

In this paper, an analysis of various control structures for two-mass drive system with backlash are presented. Theoretical model of this complex mechanical system is derived and presented. Conventional PI speed controller is compared with 2DOF-PID controller considering delays in control path and location of resonances, PID controller with additional feedback signals and fuzzy PD-I controller. The comparison of the control process and its dynamics is based on integral and time-domain quality factors.

Experimental analysis of selected control algorithms of electromechanical object with backlash and elastic joint

The paper presents laboratory tests of two selected structures of speed controller utilized in two mass system with elastic joint and backlash between motor and load. Theoretical model of the mechanical system has been derived and tested by simulation in previously published research. The aim of the article is to compare the best structure obtained by simulation with the conventional PI controller, treated as a reference. The PI speed controller was tuned according to symmetry criterion and the 2DOF-PID controller was tuned according to other method known from literature, delays in control path and location of resonances were considered. Comparison of control process was carried out on the basis of quality indicators.

PMSM laboratory stand for investigations on advanced structures of electrical drive control

This paper presents design, structure and experimental tests of a laboratory stand for the investigation on advanced control algorithms for electrical drive. The main propulsion unit is a permanent magnet synchronous motor, which is connected with a brushless DC motor operating as a dynamically adjustable load. System is controlled by a DSP with the dedicated speed and position measurement extension boards. Availability of an external DSP bus allowed to incorporate FPGA system to the control layer. The paper describes also an innovative, object-oriented approach to the implementation of the control algorithms in DSP system.

Gearless Pedaling Electric Driven Tricycle

In the paper the general conception and real construction of a three-wheel bicycle with auxiliary electric propulsion is presented. Each of the vehicle wheels is driven by an electric motor (BLDC) controlled by the central system of power distribution. The generator that charges a battery pack is driven by pedals. The vehicle speed is proportional with adjustable ratio to the pedaling velocity, whereas the power delivered to the motors is appropriately increased to the pedaling power with adjustable degree. Description and analysis of the selected modules of the vehicle are documented with prototype research results.

The impact of deterioration of the absolute position transducer on the electric drive with Permanent Magnet Synchronous Motor

The paper presents mathematical model of absolute optical encoder with parallel gray output where various parameters of the transducer can be modified (ex. number of bits, asymmetry in output waveforms, lack of signals from selected bits). The model of the non - ideal encoder substitutes the model of ideal position sensor implemented in Matlab/Simulink model of three phase PMSM (Permanent Magnet Synchronous Motor) drive with SVPWM (Space Vector Pulse Width Modulation) control algorithm. The author examines the impact of: asymmetry in output signals from the encoder and absence of signals from selected bits (simulation of damage of the transducer) to the static and dynamic properties of the drive in current and speed control loop mode. Selected methods of signal improvement were implemented in order reproduce the degradated position signal. The simulation results are verified by experiment. Quality indicators are proposed in order to determine the rate of damage of the encoder/drive. Conclusions and proposes of further research are presented.

Control algorithms in distributed system of three wheeled electric vehicle

The paper presents a concept, development and comparison of selected control algorithms used in distributed control system of a three wheeled vehicle. First simulations are carried out, then the selected algorithms are tested on a real vehicle. The article includes the description of the mathematical model of the tricycle: kinematics, dynamics, motor drives, central control system, communication network and a signal flow. The mathematical model has been implemented in Matlab/Simulink environment. The vehicle uniqueness base on that it is driven with three independent BLDC drives and equipped with generator coupled with pedals. The cyclist propels the generator, whose speed (depending an control algorithm) determines the speed of the wheels. The load of the driver varies depending on the actual load of the BLDC motors. Pedaling by wire novel idea of control scheme has been applied to the trike, which means that there is no mechanical coupling (by chain or shaft) between the pedals and the wheels of the tricycle. The lack of the standard mechanical coupling enables to implement various control methods that can be focused on: dynamic (performance) of the tricycle, energy efficiency and driving comfort. The paper discusses the problem of energy distribution between cyclist and the vehicle and focuses on control algorithms determining that distribution. Simulation are verified by experiment with waveform comparison. Analysis of research results supplemented by quality indicators. Conclusions and proposes of further investigations are presented.

Model of ADRC speed control system for complex mechanical object with backlash

The article presents simulation research concerning speed control of two mass system with elastic joint and backlash utilizing the ADRC method. The model of the plant and the structure of the ADRC speed controller are presented together with mathematical formulas allowing to determine the observer and controller gains. Proper quality indicator of control process is defined and also sample scenario of reference speed and load torque are shown. Finally the simulation results with comparison to 2DOF — FID speed controller, which acts as a reference, are carried out. Conclusions and future plans are presented.