Microprocessor Control Unit Research Articles

Высокодинамичная компенсация «мертвого времени» в электрических приводах на базе сигнальной адаптации

The article discusses the analysis and synthesis of a system of highly dynamic "dead time" compensation in the current loop of motors powered from transistor pulse-width converters. The first part of the paper provides a brief analysis of existing technical solutions, whose algorithms do not imply changes or additions to the power part of the drive and therefore are implemented exclusively by software. It is shown that the most modern methods of adaptive compensation can be considered using reference models of the control object. A non-search adaptive dead-time compensation system is proposed in the paper which provides signal self-tuning in the motor current loop, and dead-time compensation is based not on linearization or correction of nonlinear effects and delays of a pulse-width converter, but on parrying disturbing influences caused by the negative effects of “dead time”. Particular attention is paid to the practical orientation of the proposed solution; therefore, the considered algorithm is based solely on the basic principles of the control theory proven by practice. This approach allows us to ensure not only the transparency of the theoretical arguments presented in the article, but also reduce the time spent on the analysis and synthesis of the current loop, the purpose of which, ultimately, is the optimization of high-precision drives. With the absence of iteration methods of mathematics, the resources of microprocessor control units are minimized, which makes this method even more attractive in low-budget drives that do not claim to "exclusivity of integrated circuitry. The proposed algorithm was integrated into the existing current loop of an asynchronous electric drive with vector control, which proved the high efficiency of static and dynamic compensation of not only the “dead time” of the converter, but also of the non-linear effects associated with it that are difficult to analyze. The adaptive "dead time" compensation increased the efficiency of the electric drive at low motor speeds, compared to voltage boost compensation, by approximately four percent, and also reduced the motor torque ripple by about seventeen percent. An oscillogram of the phase current of a real drive with "dead time" compensation is given according to the principle of parametric voltage addition, which is the most common in practice, as well as a waveform of current with adaptive compensation action according to the principle considered in this article.

The external magnetic field modeling features of electrical complexes and systems before and after its compensation

Computer simulation of the external magnetic field of a three-phase electrical installation before and after its compensation has been carried out. The analysis of the computer simulation process of the three-pole circuit breaker external magnetic field was carried out, which made it possible to identify three features related to the selection of the direction of bypassing the circuits with phase currents, the determination of the necessary conditions for compensation of the field at a long distance, and also the calculation of the stress modulus in the control observation points under the action of the total external magnetic field of the circuits of the electrical installation and compensating sources. Calculated ratios are obtained that allow mathematical modeling of the external magnetic field of current-carrying circuits of different configurations, namely, the field of a separate current-carrying circuit, the field of circuits flowing around a three-phase current in a three-phase current system with a neutral conductor, in the case of a three-phase current system without a neutral conductor, fields of magnetic dipoles, as well as the compensating magnetic field of compensator electromagnets. It was determined that when modeling the external magnetic field, the calculation of the vector modulus of the magnetic field intensity at the point of observation and the magnetic moment of the circuit with the phase current should be carried out taking into account the pulsating components of the components that change in time according to the law of sine and cosine. Calculations confirmed that the use of an external unit of compensator electromagnets for the circuit breaker allows to reduce the impact of its external magnetic field on the microprocessor control unit of the maximum current semiconductor release by 28 units along the x and y axis and 70 units along the z axis and, thereby, prevent false activations of relay devices protection and emergency automation of low voltage electrotechnical complexes and systems.

Water Turbidity Alert System for IoT-Based Water Tank

Water has enormous benefits in daily life; quality and quantity maintained are required to be always ensured. In Indonesia, Bandung, many people keep clean water supplies in water tanks. The habit appeared as the result of their dependency on groundwater. However, some people also have already been connected to the government's water pipeline network, but they still need to have clean water tanks for prevention. The tanks need regular maintenances to ensure the stored water remains clean. When the tanks are rarely cleaned, moss appears, clogging the water pipe. The manual process of monitoring water conditions has several weaknesses, such as needing expert staff, taking more extended time, having a greater possibility of errors, and not presenting and neatly storing documentation. This paper aims to implement a water turbidity warning system in tanks and an IoT-based scheduling system for cleaning water tanks. The system will be implemented at several points of the house or water tank and can transmit data in real-time either alternately or simultaneously. The sensor detects water turbidity, and the microprocessor control unit node is in charge of processing the sensor reading data to calibrate and classify the turbidity level. Water turbidity values and levels are sent to Firebase, which resides in the cloud. The information from Firebase is passed and displayed on the application. The turbidity level of water was categorized into three: clean, turbid, and dirty. Managers, as the service providers, and consumers can monitor the tank's condition with a warning in the form of an indicator when the tank must be cleaned.

Analysis of aluminum alloys on a Polyvac E980 (Hilger Analytical) atomic emission spectrometer modified with a multi-channel analyzer of emission spectra (MAES)

A Polyvac E980 (Hilger Analytical) photoelectric vacuum optical emission spectrometer has been modified with a multichannel analyzer of emission spectra (MAES). The line of argon supply to the spark stand has been completely renewed. A precision mass flow controller with a microprocessor control unit has been installed to adjust the argon supply for different operation modes and fix the current values with the possibility of saving data for each spectrum. The microprocessor control unit coordinates the operation of the control lines and interrupts the operation of the spark generator when the stand is open or argon is absent. The modified vacuum spark spectrometer, originally designed for the analysis of iron-based alloys, has become suitable for determining the composition of non-ferrous alloys. Analytical programs have been developed for the rapid spectral analysis of AK12M2 and AK9ch aluminum alloys. The main methodological difficulty of the analysis is attributed to the necessity of monitoring high concentrations of silicon, copper, and iron along with the content of calcium impurity in the same sample. Calcium has a negative effect on the quality of castings, thus making the possibility of Ca determination an important motivation for the modification. After the preparatory work and the construction of calibration curves, the short-term and long-term repeatability of the results of spectral analysis of standard samples of aluminum alloys has been studied on the modified spectrometer. The results completely meet the standard requirements for determining the composition of aluminum alloys.

RELATED REGULATION OF BIOGAS SUPPLIES AND METHANE IN A GAS ENGINE

The results of experimental researches were received on a gas-electric installation with a rated power of 30 kW at 1500 rpm. The spark-ignited petrol drive engine (8-cylinder, 100 mm cylinder diameter, 88 mm stroke) was converted to a pure gas one. The compression ratio of 8.5 did not change. The gas fuel supply system consists of a supply line and an emergency shut-off circuit. The natural gas supply line was connected to the domestic main line through a special gas distributor. On the basis of HEINZMANN components, a system for dosing mixed gas fuel was developed, which, through a microprocessor control unit and an actuator, acted on the throttle valve of the gas mixer. In experimental researches, the composite fuel was a model gas – a mixture of natural and carbon dioxide gases, which was prepared in a zero pressure reducer before the gas mixer. With an increase in the volume fraction of carbon dioxide in the model gas by more than 34 %, a deterioration of the combustion process was observed in the steady state. In the article, based on the analysis of the experimental results of the operation of a piston gas engine on a model gas, an algorithm for the use of associated automatic control of biogas and methane feeds is substantiated. The transition from quantitative to qualitative regulation of the gas-air mixture has been substantiated. To do this, it is necessary to create two automatic control loops for the supply of air and a mixture of natural gas, which are interconnected through an external load. With the developed algorithm, as the load increases, the supply of natural gas increases, and the supply of biogas decreases. With an increase in the load of 75 % or more, a more intensive enrichment of the fuel mixture with natural gas occurs than at low and medium loads. The proposed algorithm for regulating the fuel mixture can be implemented using electromagnetic gas injectors for dosing the components of the composite fuel. Signals from sensors for oxygen and methane content in exhaust gases were selected as corrective links for the coupled control algorithm. Recommendations on the choice of tuning modes for oxygen and methane sensors have been developed.

Оптимизация пульсаций момента двигателя в электроприводе с прямым управлением

The article discusses the features of the synthesis of a hybrid method for commutation of a three-phase inverter in a classic version of drives with direct torque control (DTC), which involves the use of relay characteristics in the flux- and torque control blocks. It is proved that the output voltage of a converter based on a B6-inverter formed by only six basic vectors (excluding the zero vector) limits further optimization of flux- and torque ripples in the electrical motors. It has also been proven that with the classical drives with direct torque control, the torque ripples on the motor shaft are indeed higher than in systems with pulse width modulation. An analysis of the method was carried out which could allow reducing the amplitude of the torque ripples when drives with direct torque control are applied for motors supplied with only basic vectors of the inverter due to the modified (hybrid) method of inverter commutation. The conditions under which the hybrid control method of the inverter is really capable of reducing the amplitude of the motor flux- and torque ripples are considered. Based on the analysis of the proposed solution, the law of hybrid control of the inverter is presented by means of the formation of additional vectors of its output voltage via basic vectors of the inverter. The advantages of the method include the simplicity of drive control under development or in the existing drive control system, the implementation of which is carried out exclusively by a software product. With the absence of iterative methods of mathematics, the resources of microprocessor control units are reduced, which makes this method even more attractive in low-budget electrical drives that do not claim to be "high-end" of control blocks. The oscillograms are shown of a flux and current of motor with direct torque control motor application only with six base vectors of the output voltage of a semiconductor inverter and a drive with direct torque control by the hybrid method with additional voltage vectors based on the basic vectors of the inverter.

DEVELOPMENT AND RESEARCH OF SYNTHESIS TECHNOLOGY CONVERSION OF VEHICLE DIESEL TO GAS ENGINES WITH SPARK IGNITION

The expediency of converting transport diesel engines into gas internal combustion engines with spark ignition has been substantiated. A multifunctional synthesis technology Avenir Gaz has been developed, designed to convert diesel engines of vehicles in operation into spark-ignited gas internal combustion engines operating on a cheaper and environmentally friendly gas fuel - LPG. The synthesis technology is based on three electronic microprocessor control units Avenir Gaz 37 of level "A", Avenir Gaz 37 of level "B" and Avenir Gaz 37 of level "C". It is shown that Avenir Gaz synthesis technology of level "A" allows converting diesel engines into gas internal combustion engines with LPG supply through a gas-air mixer into the intake pipeline, and level “B” provides group or sequential LPG injection by electromagnetic gas nozzles (common rail injection system ) into the intake manifold. Avenir Gaz synthesis technology of level "C" allows the use of an electronic inductive spark ignition system with an immovable voltage distributor (with two-spark or individual ignition coils).

Development of a distributed microprocessor control system for the 6 degree of freedom motion simulator

The article deals with the design issues of a microprocessor control system for the 6 degrees of freedom motion simulator. This motion simulator is a high performance, electro-pneumatic simulator, used for test evaluation of small high dynamic flying objects. With pneumatic actuated yaw and pitch axes and an electric motor on the roll axis, the Motion simulator reproduce, in real-time, the flight motions of the actual object. The presence of a large number of servo drives with different types of executive elements in the Motion simulator required the development of a distributed multiprocessor control system. The equipment of the Motion simulator includes a number of microprocessor control units. Each contains a microprocessor control system with high-performance microcontroller having specialized peripherals, as well as equipped with all the necessary communication interfaces. Control units are maximally unified, which significantly reduces the time of their development and debugging. Due to this, units firmware is mostly identical and uses the same set of libraries.

Development of a walking aid with remote electrocardiogram measurement and global positioning system function

ABSTRACT The aging population has become one of the major issues in the world and in Taiwan. Among many aging diseases, heart disease and dementia are the main problems that affect the daily lives of the elderly and their family members. In this study, we have developed a smart walking aid with remote electrocardiogram (ECG) measurement and global positioning system (GPS) functions. The hardware of the walking aid consists of a brass column sensor with a self-developed ECG sensing circuit, a location module comprising a GPS and antenna, and a wireless transmission module with a microprocessor control unit and a Wi-Fi module. The software includes two parts: a self-developed ECG program for identifying arrhythmia with a human–machine interface to display the results and a self-developed location program integrated with Google Maps. The smart walking aid we have developed in this study was aiming to help family members or medical staff to monitor the physical conditions of their elderly family or patients who suffer from heart disease or dementia and identify their location when they experience disorientation.

DEVELOPMENT OF PROMISING SYNTHESIS - TECHNOLOGY AVENIR GAZ CONVERTING DIESELS TO GAS ENGINES WITH SPECIAL IGNITION

The object of research is the multifunctional synthesis technology Avenir Gaz (of various levels of complexity), intended for converting transport diesel engines into spark-ignited gas internal combustion engines (ICE) for operation on liquefied petroleum gas (LPG). Investigated problem: the creation of an affordable synthesis technology in terms of complexity and price, which allows converting operating diesel engines into gas internal combustion engines operating on cheaper and environmentally friendly gas fuel - LPG. Main scientific results: Avenir Gaz synthesis technology (two levels of complexity, qualified as levels "A" and "B") for converting diesel engines into gas internal combustion engines is developed and created. It is shown that the conversion of diesel engines according to the Avenir Gaz synthesis technology is carried out on the basis of the developed electronic microprocessor control systems. And the basis of the control systems is the developed and manufactured two electronic microprocessor control units Avenir Gaz 37 (hereinafter – ECU Avenir Gaz 37). ECUs in accordance with the levels of complexity of synthesis technology are qualified as – ECUs Avenir Gaz 37 "A" and Avenir Gaz 37 "B". It is shown that Avenir Gaz synthesis technology of level "A" allows converting diesel engines into gas internal combustion engines with LPG supply through a gas-air mixer into the inlet pipeline. At the same time, the Avenir Gaz 37 "A" ECU, using the signal from the Hall sensor of the distributor, limits the maximum speed of the gas engine, thereby ensuring its safe operation. And the synthesis technology Avenir Gaz 37 of level "B" allows converting diesel engines into gas internal combustion engines providing group or sequential injection of LPG by electromagnetic gas nozzles (injection system of the Common Rail type) into the intake manifold in the area close to the intake valve. Area of practical use of the research results: converting diesel vehicles, including agricultural machinery (powerful wheeled and tracked tractors, combines, etc.) into spark-ignited gas combustion engines operating on LPG. An innovative technological product: Avenir Gaz synthesis technology, which allows converting the transport diesel engines in operation into gas internal combustion engines for operation on LPG. Scope of application of the innovative technological product: naturally aspirated and supercharged diesel engines with the number of cylinders from one to six, in-line and V-shaped, with a uniform alternation of working strokes.

Educational resource of studying Robotics in STEM learning system as a factor in mastering student engineering and creative skills

The aim of the study is to find out the educational potential of studying Robotics in STEM educational system as a factor in mastering learners’ engineering and creative skills. For the pedagogical experiment, the authors arranged the control and experimental groups of children at the age of 9 to 12 years old (30 people each) in the 2019/2020 academic year. The study included testing, evaluating intelligent background criteria, and a survey among learners and educators. It resulted in the conclusions made. Robotics is a key activity in developing engineering thinking. The technique used for conducting classes in learning Robotics consists of the following components: initiating relationships, design engineering, reflection/after-action review, and development. STEM education can be based on LEGO constructing. LEGO constructing academic studies are focused on the development of verbal, creative, and engineering skills. An instructor can introduce some software to learners that allow them to design constructions and models using the tools of manual and computer-assisted three-dimensional constructional LEGO Digital Designer. This part of the course is aimed at developing general learning skills. Further development of engineering design is connected with the Arduino microprocessor control unit. It targets schoolchildren well for their study. They can launch small electronic projects. Students can master programming skills through ‘learning by doing’, as well as learn the basics of circuit technology using this platform.

Development and research the electronic control system for gas engines converted on the basis of diesels

The object of research is an electronic microprocessor control system for gas internal combustion engines with spark ignition for operation on liquefied petroleum gas. The system consists of two main subsystems, the accumulative power supply common rail LPG injection subsystem and the contactless electronic ignition subsystem with a movable voltage distributor. In addition, the control system also includes a subsystem for controlling the filling of the cylinders with the charge of the working mixture, consisting of a throttle valve and an idle speed regulator with a conical damper. The control system, depending on the software version, is capable of providing group or sequential injection of liquefied petroleum gas into the inlet pipe of each cylinder in the area close to the inlet valve. Such a control system can be used when converting (re-equipping) both new diesel engines into spark-ignition gas engines, and those that are in operation. The feasibility of such a conversion is to reduce operating costs with powerful vehicles for diesel fuel, by replacing it with cheaper and environmentally friendly liquefied petroleum gas.To test the efficiency of the control system, a D-240-LPG-«B» model gas engine was developed and manufactured to operate on liquefied petroleum gas. The gas engine was converted on the basis of the D-240 transport diesel engine (atmospheric, four-stroke, liquid-cooled, 4-cylinder engine with a piston diameter of 110 mm and a stroke of 125 mm). Reducing the compression ratio of the diesel engine was achieved by modifying a semi-closed diesel combustion chamber of the TsNIDI type into an open combustion chamber in the form of an axisymmetric «truncated cone». For efficient control of three subsystems of the D-240-LPG-«B» model gas engine, an electronic microprocessor control unit of the Avenir Gaz 37 «B» model was developed and manufactured. The tests carried out on the D-240-LPG-«B» gas engine with the Avenir Gaz 37 «B» control unit showed the efficiency of using the electronic microprocessor control system.

DEVELOPMENT OF ELECTRONIC MICROPROCESSOR UNITS OF GAS ENGINE CONTROL

The expediency of converting vehicles diesel engines into gas internal combustion engines with spark ignition has been substantiated. The advantages of using gas motor fuels, in particular, liquefied petroleum gas, are shown. Methods of supply and types of injection of liquefied petroleum gas into the inlet pipeline of a gas engine are analyzed. It is shown that the simplest way to convert diesel engines to gas engines is to equip the engine with a power supply subsystem and supply of liquefied petroleum gas to the inlet pipeline through a gas-air mixer in combination with the use of a contactless electronic ignition subsystem with a movable voltage distributor. Such re-equipment is qualified as the first level of complexity, that is, level "A". To limit the maximum gas engines speed equipped with two subsystems according to level "A", an electronic microprocessor control unit Avenir Gaz 37 "A" has been developed and manufactured. The principle of operation of the Avenir Gaz 37 "A" control unit is described. Tests of the D-240-LPG-"A" gas engine with the electronic control unit Avenir Gaz 37 "A" were carried out, which confirmed its performance. It is shown that the second level of complexity of converting diesels into gas engines corresponds to the equipment of the engine with an accumulative power supply subsystem and multi-point group or sequential injection of liquefied petroleum gas (Common Rail type) in combination with the use of a contactless electronic ignition subsystem with a movable voltage distributor and a subsystem for controlling the filling of cylinders with the charge of the working mixture. This method of converting is qualified as the second level of complexity, that is, level "B". For the operation of gas engines equipped with three subsystems according to level "B", an electronic microprocessor control unit Avenir Gaz 37 "B" has been developed and manufactured. The principle of operation of each of the three subsystems equipped with D-240-LPG-"B" gas engine is described. The tests of the D-240-LPG-"B" gas engine with the Avenir Gaz 37 "B" control unit were carried out, which confirmed its performance.

Высокодинамичный наблюдатель магнитного состояния на основе вентильного индукторного двигателя

The article is devoted to the problem of developing highly dynamic flux observers for three-phase inductor motors. The synthesis of the flux observer is based on the analysis of the instantaneous powers of the motor stator by the vector control of drives. The observation algorithm lacks integral, differential and iterative methods of mathematics. The proposed observer algorithm is implemented in a vector-matrix form for its simplest integration into the modern vector control of electric drives. The observer provides stability and high precision in drives with direct torque control, in which the variation in the angle of the spatial voltage vector of the inverter is much higher than in drives with pulse width modulation. The proposed observer algorithm can be used in cost optimized drives, because its implementation does not require “exclusive” resources of microprocessor control units. The paper presents a time invariant observer algorithm that provides high precision of the observed flux at low inductances and low voltages of the inductor motor. The measured and observed moments of the reluctance motor during the acceleration of the drive were analyzed.

Information technology for remote forced vehi-cle speed limits to improve road safety

Problems. Overcoming the consequences of traffic accidents places a heavy burden on the country's health and social services. The International Transport Forum has developed the report “Striving for Zero: High Tasks and a Systematic Approach to Traffic Safety”. Forum experts consider non-compliance with the high-speed regime on roads to be a key problem in the growth of road accidents, and the use of information technologies is one of the ways to reduce accidents. Goal. Based on the analysis, we formulated the goal of the study, which consists in creating a method and device for remote forced speed limits (RFSL) of vehicles on roads in the city and outside it in accordance with the speed limit adopted at this place. The task of this article is to formulate a concept for improving road safety in Ukraine in terms of bringing vehicle speeds to the maximum allowable values for these roads (the concept is outlined and justified), as well as developing a functional diagram of a device for remote forced vehicle speed limitation. Methodology . The analytical method is research of existing systems that can remote forced speed to limit. The method of synthesis is creation the structural scheme of a new system, based on the advantages and disadvantages of analyzed systems. Results . A method of improving road safety by remote forced speed limits of cars on roads within the city and outside them in accordance with the accepted speed limit in this place is the constant transmission over mobile networks or any other communication signal carrying information about the restrictions speed in a specific place on a specific highway. This signal after reception is processed in the microprocessor control system of fuel supply to the car engine according to a certain algorithm for the purpose of maintenance of a car speed, which does not exceed the value of restriction. Moreover, the driver of the vehicle could not, even if he wanted to, compromise such a restriction. Originality . The method of remote forced speed limitation of the car works as follows. The GSM receiver (possibly another radio receiver) constantly receives a signal that carries the value of the speed allowed on this road. In a microprocessor control unit (MCU), this value is compared to a signal from a digital speedometer or speed sensor, which is the current value of the vehicle speed. The inconsistency of these two signals or exceeding the speed of the car over the allowable speed on this road is the basis for recalculation (reduction) according to the programmed algorithm by the MCU unit of the amount of fuel required to feed the injector, as well as to reduce the duration of injectors. Reducing the fuel supply to the engine cylinders lowers the speed of the car to the acceptable values. Practical value . Functional schemes of devices for realization of the offered way on the basic types of control systems of the engine in modern cars are developed. As an example, a generalized universal functional diagram of a device for remote forced limitation of vehicle speed is given. Key words . traffic safety, speeding, remote forced vehicle speed limit, microprocessor, controller.

Electronic control for optimizing power absorption of darrieus vertical axis wind turbine by adjusting angle of attack method

This paper presents a mechanical design and electronic control for the angle of attack on the Vertical Axis Wind Turbine (VAWT) darrieus type with NACA0015 and 3 blades. This research was conducted to obtain high-efficiency absorption power on various wind speeds. The VAWT mechanical design is based on systematic calculations with a height of 150cm and a diameter of 120cm. NACA0015 airfoil with calculations in the NACA airfoil database obtained blade length of 15.892cm and width of 1.905cm. The electronic control on this system, Arduino mega controller, has input from an anemometer sensor, and rotary encoder sensor. While, the output is servo motors for 3 blade. A microprocessor control unit is programmed to control the adjustment of blade angle of attack. The angle of attack is defined by wind speed, angular speed of VAWT, and a defined TSR (Tip Speed Ratio). The angle of attack control method is PID (Proportional-Integral-Derivative) algorithm. By setting the TSR value constantly at 3-4, the angle of attack will be adapted even on any various wind speed. Expected result, the maximum power absorption will be obtained on various wind speed. This system can increase power efficiency of VAWT up to 35-40%.

Modified SVPWM Algorithm for Three Level VSI With Synchronized and Symmetrical Waveforms

To generate the required reference vector than triangle comparison based PWM techniques for three-level inverters the space vector based PWM (SVPWM) strategies contain broader choice of switching sequences. This space vector based PWM technique involves in various steps. These steps are computationally exhaustive. The SVPWM has been used in three phase inverter control system. The center-aligned PWM is the most effective way for the Microprocessor Control Unit implementation of the SVPWM, because it can easily generate the center aligned PWM of the multilevel inverters for generation of the signal of space vector pulse width modulation (SVPWM), this concept brings out the method. The inverter leg switching times are generated by this algorithm and middle vector switching times are centered in a sampled interval. The proposed algorithm does not require any sector identification. And it reduces the computational time as a result. The adjacent voltage space vectors are forming the small triangles it is called sectors. Multilevel converters can meet the increasing demand of power ratings and power quality associated with reduced harmonic distortion and lower electromagnetic interference. Furthermore to optimize switching waveforms, space vector pulse-width modulation algorithms offer great flexibility among them. Finally the results are verified through MATLAB/SIMULINK

DEVELOPMENT OF AN ELECTRONIC CONTROL SYSTEM FOR GAS-ENGINES WITH SPARK IGNITION, CONVERTED ON THE BASIS OF DIESEL ENGINES TO WORK FOR ON LIQUEFIED PETROLEUM GAS

The expediency and advantages of using gas motor fuels, in particular, liquefied petroleum gas with respect to traditional liquid motor fuels, are shown. Technical solutions for the use of liquefied petroleum gas by diesel engines are presented and analysed. The expediency and advantages of converting diesel engines to gas spark ignition internal combustion engines with respect to conversion to gas diesel engines. Developed by the Ukrainian synthesis technology Avenir Gaz has for converting diesel engines to gas internal combustion engines with spark ignition. According to the synthesis technology of Avenir Gaz, re-equipment of diesel engines of vehicles is carried out on the basis of the universal electronic control system for gas internal combustion engines, which is based on the multifunctional electronic microprocessor control unit Avenir Gaz 37. The developed electronic microprocessor control system for gas internal combustion engines with forced ignition has a modular structure and consists of two main and a number of additional subsystems. A schematic diagram of a universal electronic control system of a gas internal combustion engine with spark ignition for operation on liquefied petroleum gas is presented. The principle of operation of the main subsystems, which include the subsystem of power management and injection of liquefied petroleum gas by gas electromagnetic injectors into the intake manifold of a gas engine, and the principle of operation of the control subsystem of the ignition with two-spark ignition coils are described. A multifunctional electronic control unit Avenir Gaz 37 has been designed and manufactured. Non-motorized tests of the electronic control unit confirmed its performance. Based on the synthesis technology of Avenir Gaz using the universal electronic control system for gas internal combustion engines with the Avenir Gaz 37 ECU, the D-240 diesel engine was converted into a gas spark ignition internal combustion engine of the D-240-LPG model. Keywords: gas internal combustion engine with forced ignition, liquefied petroleum gas (LPG), electronic microprocessor control system for gas internal combustion engines, vehicles operating on LPG.

SETPOINT OPTIMIZATION FOR THE CONTROL SYSTEM OF THE MOTOR GRADER IN HEAVYLOAD MODE

Introduction. The authors suggest the optimal tuning method foran automatic control system of the heavy motor grader blade. The demonstrated system regulates the value of digging force. Moreover, the setpoint optimization criterion is the maximum of production rate.Materials and methods. The optimal setpoint is generating to the signal estimations, specifically to the measured digging force and the wheels slip ratio during the previous stroke of the motor grader.There searchincludes:development of the blade control system functional diagram including the setpoint former;meaningful estimation of the slip ratio signal for control purposes;development of the setpoint forming algorithm for a microprocessor control unit;program realization of the motor grader workflow model and simulation;development of the algorithm to compose the lookup table containing optimal setpoint values and based on simulation results;dependence of optimal setpoint on the incoming signal estimations.Results. The lookup table of optimal setpoint values is obtained, the estimations of digging force and wheels slip ratio are presented. In addition, the authors suggest the control system structure with the optimal setpoint former and also develop the former operation algorithm.Discussion and conclusion. The optimal setpoint values are theoretically validated for the motor grader control system. The tuning method for an automatic control system of the heavy motor grader blade has the following characteristics as:the optimal control criterion as the production rate;process dynamics and stochastics;the excessive slippage time ratio.

60-GHz CMOS Doppler Radar Sensor With Integrated V-Band Power Detector for Clutter Monitoring and Automatic Clutter-Cancellation in Noncontact Vital-Signs Sensing

This paper presents the design of a V-band logarithmic power detector (PD) and the integration with a 60-GHz CMOS vital-signs Doppler radar sensor to be incorporated with a microprocessor control unit (MCU) for fast automatic clutter cancellation. The PD adopts the successive detection logarithmic amplifier (SDLA) topology and achieves a high dynamic range by replacing the limited amplifiers with millimeter-wave (MMW) linear amplifiers. From the measurement results, the PD exhibits a dynamic range and logarithmic errors higher than 35 dB and within ±2 dB from 50 to 62 GHz. The whole integrated radar sensor chip is fabricated by a 90-nm CMOS process with a chip size of 2 mm $\times2.34$ mm and a dc power consuming of 243 mW. The radar chip and a 60-GHz 17-dBi patch-array antenna are integrated by bondwire interconnection on a compact single carrier board for experimental test. By incorporating the MCU to the radar chip board, the fast automatic clutter canceling can achieve more than 25-dB clutter cancellation. Moreover, it shows a successful vital-signs detection for a distance more than 1.2 m.