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The brushless DC motors with permanent magnets are used primarily in law power applications. There are no limits on weight and motor dimensions in considered motors with DC stator excitation. Brushless series connected machine with DC stator excitation do not have rotor coils. Field coil and armature coils are mounted in the stator. Armature windings are connected to DC voltage source trough power transistors commutator. Power transistors are controlled by reflective optical sensors in function of rotor position. In the report, the new principle design of the motor with DC stator excitation is considered. The new principle of design supposes individual excitation for each of the armature phase. Such approach gives an opportunity to design electrical machine with any number of armature phases spaced in phase from each other. In series connected DC machines, the field winding is connected in series with the armature winding.

Controller of the high pressure fuel pump position rod drive is the inner loop of the diesel crankshaft rotation frequency control. To make a high fast of the loop of regulating of the diesel crankshaft rotation frequency the inner loop is to be faster. Under such conditions there is a necessity to take into account the discreteness of the work of the voltage converter of the actuator. In the report the questions of design of the fuel pump rod position control are considered on the basis of the method of state-space in the discrete domain. Design includes receiving of the linear difference equations describing of the open loop with the impulse width modulation. The main feature of the description offered in the report is in the direct using the system of the differential equations to get the linear system of the linear difference equations without the step of making up the analytical solution of the differential equations.

The problem of increasing the accuracy of determining the torque and the load angle of the permanent magnet synchronous motor of an electric traction drive to the predicted level (2.5...3)% of the full-scale error is solved by an indirect method. We considered the algorithms for calculating the generalized current and voltage of the electric motor, the total power, the instantaneous values of the power factor, and the sine of the phase angle between the first harmonics of voltages and currents. We determined the requirements for the accuracy of determining these values at the level of 1% of the full-scale error. We considered the algorithms for determining the total instantaneous power losses by the indirect method at the predicted level (15...20)% of the full-scale error with the efficiency of the motor (90...95)%.

At present time, soot deposit role in the process of transient heat transfer in the diesel engine combustion chamber is studied deficiency. In the paper, a new calculation experimental method of investigation and a new mathematical model are suggested. The new method and model allow evaluating the heat insulation effect of soot deposit. The experimental research of local heat transfer was carried out using a new type of sensors for transient heat flux. Calculated local values of soot deposit show close fit (deviation was about 3 - 9%) to the experimental data. It was specified that soot deposit temperature in normal direction from the heat-loaded surface to the limit depth (detail surface) decreases about 7K per micrometer and heat flux density about 0.5%. Phase delay fluctuations of temperature and heat flux density throughout the soot deposit depth was about Δᵩ = 0.50 of crankshaft angle rotation on each micrometer.

The design of the injector tips is the primary factor of influence the fuel delivery system on parameters of a diesel engine. The location of the entrance edges spraying holes of injector tips is one of the most significant design data. In modern diesel engines, the injector tips are used with entrance edges of spraying holes are located in a volume of a cavity under a needle of an injector tip or on locking cone of the needle saddle. In this paper, the two different locations of the entrance edges of spraying holes are considered. Two real injector tips where selected for analyses and tests with different location of the entrance edges of spraying holes. The selected injector tips where modeled by using finite elements method and also these injector tips where installed on diesel and diesel characteristics where received. For selected injector tips, the three dimensional model of the injector tip parts was created.

With the development of the market of electric vehicles, the issue of efficient battery charging becomes even more urgent. Thanks to the continuous increase in the level of development of electronics, new opportunities appear to create power electrical equipment with previously unattainable characteristics. For these purposes, a universal algorithm for fast charging of LiFePO4 batteries been developed. It assumes the fastest charging of the battery without damage due to overheating or overcharging. The algorithm includes several main parts: the algorithm of initial temperature testing, the algorithm of initial trickle charging, the main current charging algorithm, the algorithm of permanent temperature testing, the main voltage charging algorithm, algorithm of permanent temperature testing, the algorithm for final trickle charging. The efficiency of the fast battery-charging algorithm studied by mathematical modeling. Computer modeling carried out using open source software.

Heavy-duty trucks and self-propelled platforms are widely spread for the purpose of transportation of heavy and bulky loads. Power units of these vehicles consist of synchronous electric generators (alternators) driven by diesel engines. The generator supplies electricity to each motor-wheel of the vehicle and to all its systems. Alternators are also used in cars' and trucks' electric systems to supply their electric and electronic devices (e.g., headlights, safety systems, etc.). Substantial reserves of production and quality improvement of such alternators are hidden in their tests technique improvement. In this paper, the software is designed for mobile and stationary test stands of the alternators. The software was created using "LabVIEW" development system. It is designed to be used with "National Instruments®" hardware.