Description:FIELD OF THE INVENTION
This invention relates to Implementation of New Hybrid Quadratic-Cuk Wide Voltage Supply DC-DC Circuit for Standalone PV Systems
BACKGROUND OF THE INVENTION
In high voltage applications of electric vehicles, the output power from the solar PV system is not reaching up to the mark. So, the scholars implementing the various DC-DC high voltage converters for sun-dependent PV networks. As of now, there are two types of high-voltage converters available in the literature which are isolated and non-isolated power converters. Here, in the isolated converters, additional components like transformers and rectifiers make the system complex. However, these isolated circuits result in excessive component energy losses, which leads to the performance of the isolated power circuit decreasing. Therefore, to overcome this drawback, a high-gain DC-DC power converter is developed in this work to enhance the power supply quality. The advantages of this Hybrid Quadratic Boost and Cuk Converter (HQBC) contribute to excessive high voltage amplification monitoring with an actively positioned one grounded power switch.
SUMMARY OF THE INVENTION
This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention.
This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.
To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.
The introduced circuit provides a wider level voltage enhancement value when correlated with the traditional level power transformation circuit. Also, it delivers a good quality current value to the load. The passive elements applied to this circuit development are less valuable. As a result, the installation area in this system is less and utilizes less cost value. Finally, this circuit reduces the per unit price of electricity production.
BRIEF DESCRIPTION OF THE DRAWINGS
The illustrated embodiments of the subject matter will be understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, and methods that are consistent with the subject matter as claimed herein, wherein:
Fig.1. Introduced network, (a). functioning state, and (b). blocking converter mode
Fig.2. Obtained waveforms for the introduced network.
The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION OF THE INVENTION
The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to clearly communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure as defined by the appended claims.
It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a",” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
In addition, the descriptions of "first", "second", “third”, and the like in the present invention are used for the purpose of description only, and are not to be construed as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" and "second" may include at least one of the features, either explicitly or implicitly.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
In high voltage applications of electric vehicles, the output power from the solar PV system is not reaching up to the mark. So, the scholars implementing the various DC-DC high voltage converters for sun-dependent PV networks. As of now, there are two types of high-voltage converters available in the literature which are isolated and non-isolated power converters. Here, in the isolated converters, additional components like transformers and rectifiers make the system complex. However, these isolated circuits result in excessive component energy losses, which leads to the performance of the isolated power circuit decreasing. Therefore, to overcome this drawback, a high-gain DC-DC power converter is developed in this work to enhance the power supply quality. The advantages of this Hybrid Quadratic Boost and Cuk Converter (HQBC) contribute to excessive high voltage amplification monitoring with an actively positioned one grounded power switch.
Network Structure of the Proposed Circuit
Power converters like DC-DC quadratic type are implemented due to their high voltage gain features. These converters have a simple design configuration, only one active switch is needed. Whereas the delay in the switch voltage is related to the output voltage for real-time usage, there will be a reduction in the voltage gain which arises from the active state voltage drop, and unwanted resistors. In this work, a DC-DC type converter is developed to enhance the voltage gain. The schematic arrangement of the first planned converter illustrated in Fig.1 is known as the Hybrid Quadratic Boost and Cuk Converter (HQBC). The Hybrid quadratic boost and capacitor-coupled converter can be achieved by integrating a quadratic boost along with a capacitor-coupled converter, although ensuring the necessity to use only one active switch for an individual phase. In the characteristics of the HQBC configuration, we can observe the potential strain handled by the controlled switch should be less than the power output of the converter. Here, the proposed power converter operates in two modes: the constant conduction method (CCM) and the discontinuous constant conduction method (DCCM). The CCM mode is used to operate the steady-state PV cell during the multi-phase configuration and it is observed in the next sections.
Analysis of CCM and Its Operation
The working principle of the converter is illustrated in Fig.1(a). The converter operates in three switching periods. Here, the converter Fig.1(a) conducts in CCM mode. As stated previously, the present quadratic boost converter generates maximum stable output with referred to the applied voltage. Here, the performance rate of the optimal voltage gain Vout/VS depends on duty cycle D, as indicated in (1). In comparison with the boost converter, the quadratic boost converter exhibits high voltage gain up to 0.7 (3.3 to 11.1 at D=0.7). Here, identifies the stable condition of the converter in Fig.1(b), seeing that all components are stable. As per the analysis, waveforms shown in Fig. 2 enable the operating cycle, and the relation between load and flow of current concerning the switching ratio is determined from the voltage-current correlation in inductors La, Lb, and Lc. Observing this, the potential load is equivalent to the potential within the capacitor terminal Ca (Vout =VCa) and concerning the recent analysis converter voltage conversation ratio is given in Eq. (5). Analyzing (5) and (1) that shows that the power converter HQBC enhances the gain amplification factor Based on the existing calculations of the power converter, the correlation among the output load and input supply is represented in Eq. (6).
V_S*D+(1-D)*(V_S-V_(C_c ))=0 (1)
V_(C_c )*D+(1-D)(V_Cc-V_Ca+V_(C_b ))=0 (2)
D(V_Cb-V_Cc)+(1-D)V_(C_b )=0 (3)
V_out/V_in =(1+D*(1-D))/〖(1-D)〗^2 (4)
V_out/V_S =(1+D)/((1-D)^2 ) (5)
According to equation (4), it can be verified that HQBC provides maximum voltage amplification in comparison with the conventional type configuration. The relation between voltage gains and duty cycle related to power converters is observed in Fig.3. This plot represents that using the suggested power converters the voltage increases throughout all the operating cycle ratios, they outperform the traditional one. Concerning the performance of the designed DC-DC converters, the characteristics of this converter are related to the quadratic-type traditional converter. Hence, here, this work is considering the solar panel, the designed converters can be combined with open-loop and closed-loop operating methods.
The power point identifiers operate the on-off cycle ratio continuously until the peak power is obtained. In a controlled feedback system, preserving the potential level at a predefined rate is necessary. A PI controller has to consider, that this proportional integral controller has to be measured, by applying a regular technique for the traditional quadratic set-up as described. Additionally, a feedback control system has to apply an adaptive switching to the inductor input current iLa and a proportional-integral adjustment system to calculate the inductor input current iLa by applying the voltage.

Variations of Electric Potential and Currents
The variations of electric potential and currents in the semiconductor materials are controlled by the power delivered and the operating potential of the converter. A study of the HQBC converter indicates that peak voltage is preserved by the switch S represented by equation (6), at which VCa, VCb represent the mean values and ΔVCa, ΔVCb represent the voltage fluctuations of Ca, Cb, simultaneously. The maximum current rating of the switch changes based on the working condition related to the converter operating phase ratio of the D and output load current. The maximum current rating of the switch is represented by equation (6). As per the above investigation, there is a chance to determine the decreased voltage pressure by the switch compared to the output delivered within the converter (Vo). Still; it leads to a higher current pressure in comparison to the traditional quadratic boost because it needs to supply current flowing through capacitors Ca and Cd.
〖VC_a 〖=(Δ*V_(C_a ))/2〗_Cb*(Δ*V_Cb)/2〗_Qmax (6)
〖I=((2D+D^2+D^3)I_out)/((1-D)^2 )〗_Qavgmax (7)
〖VCa=(Δ*V_(C_a ))/2〗_Qmax (8)
〖I*((2D+D^2+D^3)I_out)/((1-D)^2 )〗_Qavgmax (9)
{■(V_Db=V_Ca+(Δ*V_Ca)/2-V_Cb-(Δ*V_Cb)/2-V_Cc+(Δ*V_Cc)/2@V_Dc=V_Ca+(Δ*V_Ca)/2-V_Cb-(Δ*V_Cb)/2@V_(Da,d)=V_Cc+(Δ*V_Cc)/2)┤ (10)
{■(V_Da=V_Cc+(Δ*V_Cc)/2@V_Db=V_Ca+(Δ*V_Ca)/2-V_Cc+(Δ*V_Cc)/2@V_Dc=V_Ca+(Δ*V_Ca)/2@V_Dd=V_Cd+(Δ*V_Cd)/2)┤ (11)
The voltage variations across the diode terminals of the HQBC are represented in (11). Based on those equations, it may be expected that the potential variations across diode terminals are reduced compared to the power delivered (Vo). In HQBC converter potential variations across the terminals of the diodes are represented by (12). The peak mean values of diode currents D1 to D4 are shown in equations (13), and (14) HQBC converter current strain,
{█(I_(Davg max)=I_(Ddavg max)=I_out@I_(Dbavg max)=(D(1+D))/〖(1-D)〗^2 @I_(Daavg max)=I_out/〖(1-D)〗^2 )┤ (12)
{█(I_(Dcavg max)=I_(Ddavg max)=I_out@I_(Dbavg max)=(D(1+D)I_out)/〖(1-D)〗^2 @I_(Daavg max)=〖(1+D)I〗_out/〖(1-D)〗^2 )┤ (13)
Δ*iL_aT1=D V_S/(L_a f_pwm )=D ((1-D)^2)/(1+D(1-D)) V_out/(L_a f_pwm ) (14)
Δ*iL_aT2=D V_S/(L_a f_pwm )=D ((1-D)^2)/(1-D) V_out/(L_a f_pwm ) (15)
〖L_a〗_(max⁡T 1)=D*V_out/(Δ*iL_a f_pwm ) (16)
L_(a max⁡T 2)=D*V_out/(Δ*iL_a f_pwm ) (17)
L_(b max⁡T 1)=D*V_out/(Δ*iL_b f_pwm ) (18)
L_(b max⁡T 2)=D*V_out/(Δ*iL_b f_pwm ) (19)
L_(c max⁡T 1)=D*V_out/(Δ*iL_C f_pwm ) (20) L_(c max⁡T 2)=D*V_out/(Δ*iL_c f_pwm ) (21)
Conclusion: The introduced circuit provides a wider level voltage enhancement value when correlated with the traditional level power transformation circuit. Also, it delivers a good quality current value to the load. The passive elements applied to this circuit development are less valuable. As a result, the installation area in this system is less and utilizes less cost value. Finally, this circuit reduces the per unit price of electricity production.
, Claims:1. A DC-DC power converter, comprising: Hybrid Quadratic Boost and Cuk Converter.
2. The system as claimed in claim 1, wherein the system is configured to minimize energy losses by reducing the number of inductive and magnetic elements, leading to improved power conversion efficiency.
3. The system as claimed in claim 1, wherein the combined effect of the quadratic boost and Cuk stages results in a voltage gain exceeding that of either stage alone, enabling sufficient output voltage for high-voltage electric vehicle systems from a low-voltage solar PV input.
4. The system as claimed in claim 1, wherein the system is optimized for interfacing with sun-dependent solar photovoltaic sources by dynamically adapting to varying input voltages while maintaining a stable high-voltage output.
5. The system as claimed in claim 1, wherein the system operates without magnetic isolation, thereby reducing system complexity, component count, and energy losses associated with transformers and rectifiers.