Mechanics, Materials Science & Engineering, March 2016
ISSN 2412-5954
Intellectual Drive With Electric Engines On a Stock Car Bazhynov O.V.1, Veselaya M.A.1 1
Kharkiv National Automobile and Highway University, Kharkov, Ukraine DOI 10.13140/RG.2.1.3296.9369
Keywords: electric drive, ac electronic motor, current, voltage, inverter, current controller.
ABSTRACT. The concept of installing smart electric drive, battery unit and control system of a stock car is presented. This work is devoted to AEM control law consisting of auto power plant, providing minimum current consumption for a given traction and speed mode. The practicability of AEM static model usage in the process of synthesis of optimal control of auto power plant with traction electric drives and also choice and substantiation of its basic parameters and characteristics is demonstrated.
Introduction. The complex problem of the scientific substantiation of the basic parameters and characteristics is appeared during designing the new auto power plants. To solve this problem techniques based on the conducting numerical experiments with appropriate mathematical models are used. However, comparative analysis of different design solutions is not possible without algorithms control power plant optimization as whole and individual aggregates that are the parts of it. This work is dedicated to the investigation of AEM control law consisting of auto power plant, providing minimum current consumption for given traction and speed mode. to identifying mathematical models of traction electric drive different vehicles and synthesis of optimal control auto power plants are appeared in recent years. This shows the urgency of the problem. In particular approaches to modeling the power plant of hybrid vehicles, including the AEM as an auxiliary electric drive, and relevant control systems are shown in the articles [1-4]. The problems of AEM mathematical modeling and optimization of the stator current vector are analyzed in the articles [4-8]. The traction electric motor model. However, the task of comparative analysis of different design solutions of auto power plants on the basis of computing experiment raises a number of features in the synthesis models both the object of control and controlling actions. The questions of technical implementation control laws are insignificant. At the same time optimal control vector current on all traction and speed modes under the given constraints and quality criteria of particular importance achieve special value. Herewith the level of complexity of the models ought to provide the ability of the power plant examination in a standard driving cycle of the vehicle. Let us conduct the investigation of different approaches to the modeling of traction electric vehicle based on the optimal control of AEM vector stator current estimate of the magnitude and modeling errors caused by neglecting AEM dynamic properties under control stepped actions. The object of article. To achieve this goal it is necessary to develop the block diagrams of dynamic and static models of electric traction and transmission model car. Comparative analysis of models can be made on time dependences of the main variables obtained for stepped control actions and optimal management of the stator current vector, taking into account the restrictions permissible mode of AEM field. MMSE Journal. Open Access www.mmse.xyz
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Mechanics, Materials Science & Engineering, March 2016
ISSN 2412-5954
Let us consider the coordinate system connected to the rotor AEM and fixed relatively to it. We assume that the axis d is aligned with the axis of the magnetic flux of the rotor. In this coordinate system equations for electromagnetic processes in AEM scalar form can be written as
(1)
where
,
,
,
are projections of vectors of voltage and current of the stator to the axis
coordinate system which rotates, transverse axes, rotor, moment.
full inductance of stator windings in longitudinal and
resistance phase windings,
the number of pole pairs,
vector flux stator on the magnetic flux of the
angular velocity of the rotor,
AEM electromagnetic
Based on equations reduced electromagnetic control point AEM can be carried out by adjusting the longitudinal and transverse components of the stator current area subject to the limitations of acceptable modes. The component of the stator current AEM and required for a given traction and speed limits are determined by the selected test quality control. If the criterion of quality acts minimum total current consumption AEM in static mode, the optimal relationship can be obtained from the criterion:
,
where
(2)
is module vector stator current (AEM total
current consumption); M VD zd
electromagnetic moment that is set needed to maintain the desired auto traction speed
mode, electromagnetic control signal point AEM; M VD max
maximum torque of AEM.
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;
Mechanics, Materials Science & Engineering, March 2016
ISSN 2412-5954
Obviously the best according to selected criteria ratio of longitudinal and transverse components of the current can be achieved only in those areas of the region acceptable modes of AEM, where there is no mode of field weakening. As a regulator traction electric current in [4] the controller looks like,
(3)
where Raq
k pd ac L1q
Usually it is
ac L1d ; R1 ;
; ,
,
kiq
;
are assessment values of
,
ac R1 Raq ; and
;
therefore;
is parameter that determines the required bandwidth closed-loop control system. .
The first two components of expressions for the longitudinal and transverse channels are standard PI control. The third component of data expressions are intended to compensate for the current dynamics of connectivity between the longitudinal and transverse channels of AEM model. The last fourth components provide active damping. Converting received on the output current regulator voltage task signal with coordinate system that rotates in fixed
can be carried out according to the expression [5]:
,
where
(4)
is the AEM angle rotor.
Inverse transformation of coordinates to components of the stator current entering the input of the regulator is performed according to terms:
(5)
The transformation phase 2/3 for signals of voltage setting is carried according to expression [6, p.21]:
MMSE Journal. Open Access www.mmse.xyz
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Mechanics, Materials Science & Engineering, March 2016
ISSN 2412-5954
(6)
The value of phase currents obtained based on sensor signals a fixed coordinate system
and
power can be reduced to
using expressions:
.
(7)
The inertia of the three phase inverter with LIM can be characterized by the amount of clean delay period of pulse width modulation . To simplify the task let us consider the inverter as a linear amplifier with amplification constant and time constant
[6, s.123],
(8)
where
is differentiation operator.
Using coordinate transformations, you can receive description of the three phase LIM inverter with first fixed , and then connected to the rotor coordinate system that rotates: :
;
(9)
;
(10)
;
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(11)
Mechanics, Materials Science & Engineering, March 2016
Tu
d ud dt
jTu ud
e
jTu
d uq dt
Tu uq
e
ud
ISSN 2412-5954
juq
.
ku ud*
;
(12)
jku uq* ;
(13)
(14)
The last expression (14), which is mathematical description of the LIM inverter in coordinate system which rotates , displays as existing mutual longitudinal and transverse control channels, which are enhanced by increasing the AEM rotor speed. These mutual influences can be seen as disturbance acting on the current circuits. For their minimization it is necessary to reduce the value of the LIM period. Automobile transmission elements that load the electric drive are characterized quite large exact moment of inertia. Process time coefficients speed control rotor AEM consisting propulsion vehicle are significantly greater than time constants of AEM, current regulator and inverter with LIM. This allows ignoring the dynamic properties of the actual electric traction in the study of different traction speed modes of auto power plant. One of the options simplified block diagram of the traction electric drive with AEM is shown in Fig. 1.
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Mechanics, Materials Science & Engineering, March 2016
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+
+ +
+
+ +
+
-
Fig. 1. The simplified block diagram of a static model traction electric drive with ac electronic motor The shown model takes into account only the static properties of the optimal control of AEM longitudinal and transverse components of stator current. The reaction of vehicle transmission model with traction electric drive based on AEM on stepped control effect in motion with constant gear ratio transmission without the road longitudinal slope ( 0 ) is shown on Fig. 2.
MMSE Journal. Open Access www.mmse.xyz
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Mechanics, Materials Science & Engineering, March 2016
ISSN 2412-5954
Fig. 2. Electric vehicle reaction on stepped control effect In this case, the static electric traction model is used. AEM rotor speed is expressed in rotations per minute: . is moment of resistance reduced to a AEM shaft. The redistribution in the areas of the region acceptable modes of AEM, where it is impossible to maintain the optimal ratio of longitudinal and transverse components of the currents is carried so that the total power consumption does not exceed , and electromagnetic torque is close to the given one. Figure 3 illustrates the nature of the current change and AEM primary voltage at this traction and speed mode. Power consumed by AEM can be defined as the sum of instantaneous power phase stator.
(15)
The change of power consumed from the power network AEM, while auto accelerates or of that which is given to the network as a result of the kinetic energy recovery braking is shown on Figure 4.
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Mechanics, Materials Science & Engineering, March 2016
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Fig. 3. Change of longitudinal and transverse components of current and voltage brushless electric vehicle traction under stepped control actions.
Fig. 4. Power consumed or given in traction electric onboard network of the auto. The comparative analysis of auto transmission model with the electric traction powertrain when using static and dynamic models of AEM at the stepped control effects and optimal control of current vector shows that mean square error of current components of current and voltage, electromagnetic torque and rotor speed of AEM are: ; ; ; Ud
0,56286 B ;
Mvd
0,37262 Ă? ĂŹ ;
accordingly.
Summary. Thus, the extent of errors of basic variables of modeling caused by neglect of AEM dynamic properties, are quite small compared with the range of changes in the relevant variables. It confirms the use of AEM static model in the synthesis of optimal control of power plant electric auto traction and also the choice and grounding of its basic characteristics and parameters. References Obosnovanie ispolzovaniya ventilnih elektricheskih [Usage substantiation of ac electronic motors in 33. [ [Synergetic approach to design auto power plant]. Ves
133.
[ plant]. Transport, Environment Sustainable Development: XIII International Scientific Conference, 10 12 May 2007. Varna, Bulgaria, pp. 613 619. MMSE Journal. Open Access www.mmse.xyz
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[4] Borodenko, Y.M., Serikov, O.P., Smirnov O.P., (2008), Systema keruvanya hibridnoy silovoy ustanovkoy z pnevmodvigunom system of the hybrid power plant with pneumatic engine 38. [ [Prospects for the development of power supply systems of vehicles]. Transport, Environment Sustainable Development: XIV International Scientific Conference, 8 10 May 2008. Varna, Bulgaria, pp. 295 301. [ otor usage in electrical drive]. Vestnik KhNADU, 47. [ features of hybrid power plants]. Transport, Environment Sustainable Development: XIV International Scientific Conference, 8 10 May 2008. Varna, Bulgaria, pp. 291 295. [ to electro mechanics]. Economic and legal aspects of social priorities and trends in the development of education under conditions of integration Ukraine into the global educational system: Scientific Conference, 17 18 April 2008. Kharkov, pp. 112 115.
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