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Bumping is a prerequisite for flip‐chip attachment of bare dies. For silicon semiconductors bumping is normally performed on the ICs at wafer scale. Bumping can be performed by micro‐plating or vacuum deposition techniques. Mechanical methods are also well known. In this paper a bumping process based on tin/lead alloy plating is reported. The plating bath presented enables the deposition of both solder compositions used for flip‐chip attachment, the eutectic and the lead‐rich. All key issues of the plating process covering plating equipment, electrolyte characteristics and plating process parameters are discussed. Methods of bump characterisation and quality assurance are reported as an important part of the bumping process. The deciding process parameters leading to high quality solder bumps are demonstrated.

The main purpose of this paper is to evaluate the two energy saving position control strategies for AC drives valid for a wide range of boundary conditions including an analysis of their energy expenses.

For energy demands analysis, the optimal energy control based on mechanical and electrical losses minimization is compared with the near-optimal one based on symmetrical trapezoidal speed profile. Both control strategies respect prescribed maneuver time and define acceleration profile for preplanned rest-to-rest maneuver.

Presented simulations confirm lower total energy expenditures of energy optimal control if compared with near-optimal one, but the differences are only small due to the fact that two energy saving strategies are compared.

Developed overall control system consisting of energy saving profile generator, pre-compensator and position control system respecting principles of field-oriented control is capable to track precomputed state variables precisely.

Energy demands of both control strategies are verified and compared to simulations and preliminary experiments. The possibilities of energy savings were confirmed for both control strategies.

Experimental verification of designed control structure is sufficiently promising and confirmed assumed energy savings.

The purpose of this paper is to elaborate a robust model‐based protective control algorithm for multi‐mass motor drives that are subjected to physical and safety constraints on their variables.

The algorithm relies on the off‐line computed maximum robust controlled invariant set or its approximation for the given drive system and imposed constraints. It can be used to patch any existing drive control scheme with a firm constraints satisfaction guarantee. The online patch implementation is actually a simple correction of the control signal computed with the existing control scheme, with a mandatory state observer.

Performance of the patch is tested on a two‐mass drive system in combination with classical two‐mass drive speed controllers – P+I and reduced state controller. All constraints violations that exist in the presented responses obtained without the protection patch are suppressed by using the patch which shows the effectiveness of the approach. A brief implementation analysis shows that a digital signal processor could be used for online implementation of the controller with the protective patch.

Robust invariant sets theory is efficiently and effectively used in a new application area – protection of multi‐mass electrical drives.

This paper aims to address the speed and flux tracking problem of an induction motor (IM) drive that propels an electric vehicle (EV). A new continuous control law is developed for an IM drive by using the backstepping design associated with the Robust Integral Sign of the Error (RISE) technique.

First, the rotor field-oriented IM dynamic model is derived. Then, a RISE-backstepping approach is proposed to compensate for the load torque disturbance under the assumptions that the disturbances are C² class functions with bounded time derivatives.

The numerical validation results have presented good control performances in terms of speed and flux reference tracking. It is also robust against load disturbances rejection and IM parameters variation compared to the conventional Field-Oriented Control design. Besides, the asymptotic stability and the boundedness of the closed-loop signals is guaranteed in the context of Lyapunov.

A very relevant strategy based on a conjunction of the backstepping design with the RISE technique is proposed for an IM drive. The approach remains simple and can be scaled to different applications.

Whenever capitalism in the West appears to be dragging with unresolved problems, then quite a few people, including professional economists, begin to think that perhaps socialism is a better alternative. Conversely, in the East even a larger number of people, including economists (who are not activists), seriously believe that in view of their shortages and meagre incomes capitalism would be a better alternative.

This paper describes the development of closed loop control techniques for matrix converter fed induction motor drives. A prototype drive rated at 2.5kW is used to demonstrate closed loop speed control using vector control technique. Solutions to the special problems associated with the power circuit and implementation of closed loop control in the matrix converter drive are given. Experimental results demonstrating the control techniques are presented for both motoring and generating operations of the matrix converter drive in transient and steady‐state.

The present and potential applications of screen‐printing thick film technology to the field of chemical sensing are briefly reviewed in the first part of the paper. The second part is devoted to the search for new routes to selectivity for basically non‐selective gas sensors.

This paper proposes a new discrete‐time formulation of state‐space model for voltage source inverter (VSI) fed AC motors, introducing the free evolution of the motor state and characterized by both the simplification of torque and flux output equations and the definition of a predictive reference frame oriented on the rotor free evolution vector. The potential of the proposed model for high dynamics discrete‐time controller synthesis is illustrated through an application to SM‐PMSM.

The paper aims to overcome the shortcomings that proportional‐integral‐derivative (PID) control for unmanned robot applied to automotive test (URAT) needs a priori manual retuning, has large speed fluctuations and is hard to adjust control parameters. A novel control approach based on fuzzy neural network applied to URAT was proposed.

According to the target vehicle speed and driving command table, the multiple manipulator coordinated control model was established. After that, the displacement of throttle mechanical leg, clutch mechanical leg, brake mechanical leg and shift mechanical arm for URAT was used as input of fuzzy neural network (FNN) model, and vehicle speed was used as output of FNN model. The number of membership functions was three, and the type of that was generalized bell membership function (gbellmf). The hybrid learning algorithm which combined with back propagation algorithm and least square method was applied to train the model. The Sugeno model was selected as fuzzy reasoning model.

Experimental results demonstrated that compared with PID control method, the proposed approach can greatly improve the accuracy of vehicle speed tracking. The approach can accurately realize the vehicle speed tracking of given driving test cycle. Therefore, it can ensure the accuracy and effectiveness of automotive test results.

Future work will focus on improving the efficiency of this learning algorithm.

The paper provides effective methods for improving the accuracy of speed tracking and repeatability.

After establishing the multiple manipulator coordinated control model, this paper proposes a novel control approach based on FNN for URAT.

The purpose of this paper is to design the control for a new type of DC converter that can be used in low voltage and low power DC drives, e.g. in cars and robots.

Based on the theory of the switching systems, the existence condition of the limit cycle for the novel DC/DC converter is formulated.

The feed forward control which realizes the limit cycle is designed. The first experimental results show that the designed control of the DC/DC converter is effective in solving the control problem of DC drives and allows the use of a low input voltage as power source for the standard DC drive.

Today DC/DC converters play a key role in power conversion and distribution. The presented DC/DC converter has a very simple circuit and allows changing the output voltage in the wide range that is needed for the DC drive control.