Description:A METHOD, APPARATUS, AND SYSTEMS FOR DISTRIBUTING THE REACTIVE POWER AMONG MULTIPLE H-BRIDGE BLOCKS
Technical Field:

[001] Embodiments disclosed in the present application relates to distributing the reactive power to enhance performance and specifically to a method, apparatus, and systems for distributing the reactive power among multiple H-Bridge blocks.

Background:
[002] Institute of Electrical and Electronics Engineers (IEEE) standard IEEE-1574 (2018), clause 5 highlights the necessity of reactive power (Q) support for grid stability, which is crucial for utility-scale renewables and grid storage applications. Conventional control techniques support independent regulation of grid system’s total active power (P) and total reactive power (Q). Independent regulation of grid system’s total active and reactive power does not provide optimal performance due to several factors such as total harmonic distortion (THD), higher switching frequencies, and causes thermal stress on the individual components of the system. Thus, there is a need to develop a novel control technique to enhance the performance of grid systems.

Summary:
[003] Embodiments of a method, apparatus, and systems for distributing the reactive power among multiple H-Bridge converters or blocks are disclosed. Embodiments of the invention disclosed here teach one or more techniques to, (a) enable independent control of both active power (P) and reactive power (Q) to one or more H-bridges of the plurality of H-Bridges; (b) dynamically determine total reactive power (Q) requirement for the plurality of H-Bridges and then efficiently distribute the total reactive power (Q) among the one or more H-bridges of the plurality of H-Bridges. Such an approach may extend the utilization range of the one or more H-Bridges thereby mitigating the risk of the one or more H-bridges entering into the over modulation phase. Effective distribution of reactive power between the H- Bridge blocks may improve the operating range while maintaining linear modulation without harmonic injection.

Brief description of Drawings:
[004] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments of the present invention and, together with the description, further serve to explain the principles of the invention and to enable a person skilled in the pertinent art(s) to make and use the invention. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference
[005] The following description and drawings and the drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, algorithm, and other changes. Portions and features of some embodiments may be included in, or substituted for, those of other embodiments. Embodiments set forth in the claims encompass all available equivalents of those claims.
[006] FIG. 1 is a power architecture 100, which illustrates a cascaded configuration of a plurality of H-Bridge converters according to an embodiment.
[007] FIG. 2 is a flow-chart 200 depicting an embodiment of an operation of the control logic 280 according to an embodiment.
[008] FIG. 3 is a generalized dq architecture for a grid-connected cascaded H-Bridge converters according to an embodiment.
[009] FIG 4 is an example representation of the control logic 280, which generates voltage component values (vid) and (viq), respectively, of active power and reactive power provided to one or more H-bridge converters according to an embodiment.
[0010] FIG 5 is an example representation of the control logic 280, which generates voltage component values (viq and vidq), respectively of active power and reactive power provided to one or more H-bridge converters according to an embodiment.
[0011] FIG.6 illustrates an example of a vehicle battery charging system according to an embodiment.
[0012] FIG. 7 illustrate example waveforms generated while charging and discharging a battery in the vehicle battery charging system according to an embodiment.

Detailed Description:
[0013] While the present invention is described herein with reference to illustrative embodiments for particular applications, it should be understood that the invention is not limited thereto. Those skilled in the relevant art(s) with access to the teachings provided herein will recognize additional modifications, applications, and embodiments within the scope thereof and additional fields in which embodiments of the present invention would be of significant utility.
[0014] Reference in the specification to “one embodiment”, “an embodiment” or “another embodiment” of the present invention means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrase “in one embodiment” or “in an embodiment” appearing in various places throughout the specification are not necessarily all referring to the same embodiment.
[0015] FIG. 1 is a power architecture 100, which illustrates a cascaded configuration of a plurality of H-Bridge converters according to an embodiment. In one embodiment, the power architecture 100 includes “n” grid blocks 110-1 to 110-n, a converter block 130 comprising “n” H-Bridge converters 140-1 to 140-n, and “n” direct current (DC) port interfaces 114-1 to 114-n, an LCL filter 150, an alternating current (AC) power source 170 or AC grid 170, and a logic 180. In one embodiment, converter block 130 handle power exchange between DC power domain and the AC power domain.
[0016] In one embodiment, each of the DC ports 114 includes a DC bus filter capacitor C 115 and the DC ports 114-1 to 114-n may be dispositioned in parallel between the first terminals of each of the H-Bridge converters 140-1 to 140-n and the first terminals of the grid blocks 110-1 to 110-n, respectively. In one embodiment, the grid blocks 110-1 to 110-n may include storage units and the AC power value from the AC grid 170 may be converted into DC and stored in the DC storage units 110-1 to 110-n. In another embodiment, the grid blocks 110-1 to 110-n may include photovoltaic cells, which generate DC power and the H-bridge converters 140-1 to 140-n may convert the DC power values into AC and provide such AC values to the AC grid 170 that can be used for powering the domestic appliances or charging batteries, for example. In yet another embodiment, the grid blocks 110-1 to 110-n may include a combination of grid storage units and PV units, for example, and the. In one embodiment, the DC ports 114 may include isolated DC-DC converters (Vdck | k=1, 2,…n) to provide a bi-directional power flow capability.
[0017] In one embodiment, the AC power source 170 may provide voltage vg corresponding through the LCL filter 150 and the output of the LCL filter 150 may be referred to as total (or combined) voltage input Vi 158, which may be applied across the plurality of H-bridge converters 140-1 to 140-n. In one embodiment, the LCL filter 140 may include two inductors Lg 153 and Lf 153 and a filter capacitor Cf 154. In one embodiment, the two inductors Lg 153 and Lf 152, respectively, represent a grid side and a converter side inductance and Cf 154 represents a filter capacitor. In one embodiment, the values of Lg 153, Lf 152, and Cf 154 values may be chosen based on the reactive power ratio absorbed in the filter capacitor, tolerable current ripple on the converter side, resonance frequency, and the filter inductance ratio. In one embodiment, grid current ig 157 and iL 156, respectively, represent a grid current and a converter side inductor current.
[0018] In one embodiment, at least one or more of the H-bridge converters 140-1 to 140-n of the plurality of H-bridge converters 140-1 to 140-n may be provided with a modulated reactive power (Qk*)|(k=1, 2…n) based on the reactive power demand (Qreq), which is determined in compliance with the standards set in IEEE-1574 (2018), clause 5. In one embodiment, vik|(k=1, 2…n) represents the modulated voltage provided to the kth H-bridge converter and vi represents the combined modulated voltage of the plurality of H-bridge converters. In one embodiment, the modulated voltage vik and therefore the reactive power (Qk*) for each of the one or more H-bridge converters is determined using a novel control technique according to an embodiment of the present invention.
[0019] In one embodiment, the logic 180 may include a processor 182, a memory 184, a communications block 186. A PQ controller 187, and a Q distributor 188. The memory 184 may be used to store instructions, data, and libraries and may be RAM, ROM, EPROM, based on DDR and such other technologies. In one embodiment, the memory 184 may be used to store total P and Q values and the active (Pk*) and reactive (Qk*) power references for the kth H-bridge 140. The communications block may include one or more wired LAN, a baseband processor, a Wi-Fi processor, a Bluetooth processor and other such hardware, firmware, and software blocks to enable efficient and error free communication between the logic 180 and converter block 130, for example.
[0020] In one embodiment, the processor 182 may include a complex instruction set computer (CISC) architecture or a reduced instructions set computer (RISC) architecture. Further, the processor 182 may include a central processing unit (CPU) or graphics processing unit (GPU) or neuromorphic computing unit (NPU), or an artificial intelligence based integrated circuit or an accelerator or a digital signal processor (DSP) or a microcontroller or a combination of any such processors.
[0021] In one embodiment, the processor 182, may receive a percentage of rated apparent power as specified by Institution of Electrical and Electronics Engineers (IEEE) standard 1547 (2018), clause 5. In one embodiment, the processor 182, based on the IEEE standards 1547 (2018) Clause 5, may set the value of required reactive power (Qreq) to about 40-44% of the rated apparent power (P). In one embodiment, the processor 182 may use the 40-44% of the rated apparent power to support the reactive power while the rated active power is either drawn or supplied to the grid for voltage regulation.
[0022] In one embodiment, the processor 182 may determine the reactive power to be distributed among each of the plurality of the H-Bridge converters 140-n. In one embodiment, the processor 182 may distribute the reactive power (Qk*) among each of the plurality of H-Bridge converters 140-n. In one embodiment, the processor 182, may enable an efficient voltage regulation technique based on the distribution of the reactive power among each of the plurality of H-Bridge converters. In one embodiment, the processor 182 may enhance the voltage regulation by distributing the reactive power (Qk*) among the plurality of H-Bridge converters 140-n, especially used in medium voltage AC (MVAC) to low voltage AC (LVDC) applications such as photovoltaic cell-based applications, electric vehicle battery charging applications and such other applications.
[0023] In one embodiment, the processor 182 may send a start signal to the PQ controller 187 based on sensing the availability of a voltage signal at the output of the LCL filter 150. In one embodiment, the PQ controller 187 may implement a control technique to determine the P*k and Qk* for the one or more H-bridge modules 140-1 to 140-n using a “dq” control architecture depicted in FIG. 3.
[0024] With reference to FIG. 3, in one embodiment, Vdck 305 may represent the DC port voltage for the kth H-bridge, wherein (k = 1, 2…n). In one embodiment, in rectifier applications, each H-bridge converter’s DC bus voltage loops provide individual power references (P*k|k=1, 2, ….n) for kth h-bridge converter, In one embodiment, the total active power demand may be expressed as Preq 315 = Ʃ (n=1 to k) Pk*, and if the reactive power transferred by the kth H-bridge is Qk*, then Qreq 320 = Ʃ (n=1 to k) Qk*. In one embodiment, the processor 182 may generate vid 375 and viq 380 based on Preq 315 and Qreq 320 and the inner loop currents iLd 345 and iLq 350. In one embodiment, the PQ controller 187 may subsequently generate the modulation signal vi by applying, for example, inverse Park transformation on vid 375 and viq 380. In one embodiment, since the inner loop currents iLd345 and iLq350 flowing through the H-bridge converters 140 are identical, the vid 375 and viq380 may be the variables and xd and xq may represent the Park-transformed components of x, wherein x Ꞓ {vg, iL, vi}.
[0025] In one embodiment, the combined voltage, vi, can be expresses in terms of vik as shown in Equation (1) below, which can be further represented in the dq domain and expressed as depicted in Equation (2) below:
[0026] vi = Ʃ vik | (k =1, 2,…n) --------------------------------------------------------Equation (1)
[0027] vid = Ʃ vidk; and viq = Ʃ viqk-----------------------------------------------------Equation (2)
[0028] In one embodiment, further, the apparent power transferred by the kth H-bridge converter to the grid 110-k may be expressed as shown in Equation (3) below:
[0029] Pk + jQk = ½ {[(vidk + jviqk)] x [(iLd 345 + jiLq 350)]} --------------------------Equation (3)
[0030] In one embodiment, the apparent power may be expressed in terms of active power (Pk) and reactive power (Qk) individually as depicted, respectively, in Equations (4 and Equation (5), shown below:
[0031] Pk = ½ {[(vidk) x (iLd 345)] + [(viqk) x (iLq 350)]} ----------------------------- Equation (4)
[0032] Qk = ½ {[(vidk) x (iLq 350)] – [(viqk) x (iLd 345)]} ----------------------------- Equation (5)
[0033] Now, using Equations (4) and (5) and solving for vidk and viqk, respectively, results in the following Equations (6) and (7), shown below:
[0034] vidk = [2 (Pk* iLd 345 + Qk* iLq 350) / i2Ld 345 + i2Lq 350] ---------------------------Equation (6)
[0035] viqk = [2 (Pk* iLq 350 - Qk* iLd 345) / i2Ld 345 + i2 Lq 350] --------------------------Equation (7)
[0036] In one embodiment, it may be observed from the Equations (6) and (7) that the active power (Pk*) and the reactive power (Qk*) for the kth H-bridge converter 140 may be set independently of any other H-bridge converters 140 of the plurality of H-bridge converters 140-1 to 140-n.
[0037] In one embodiment, the PQ controller 187 may be either designed in hardware or programmed using software instructions, stored in the memory 184, to determine the active power Pk* and Qk* for the kth H-bridge based on the corresponding Vdck loop across C115 (of FIG. 1) as illustrated by the control architecture of FIG. 3. In one embodiment, the PQ controller 187 may send a “completed” signal to the processor 182 after completing the determination of Pk* and Qk*.
[0038] In one embodiment, the processor 182 may send a “distribute signal” to the Q distributor 188 to initiate the distribution of the reactive power (Qreq) among the one or more H-bridges and a technique for distribution of reactive power (Qreq) is described below. Though PR controller 187 and Q distributor 188 is depicted as two separate blocks to enhance the ease of understanding, the functionality of PQ determination and distribution of Q may be implemented in a single block as well. In one embodiment, the functionality provided by the PR controller 187 and the Q distributor 188 may be implements in the hardware, software, firmware as a combination of any thereof.
[0039] In one embodiment, for a given Qreq, the reactive power (Qk*) for the kth H-bridge 140-k may be obtained from a constraint of overmodulation depicted in Equation (8) below:
[0040] V2dck >= v2idk + v2iqk -------------------------------------------------------------Equation (8)
[0041] Now, combining Equations (6), (7) and (8), the limit of reactive power (Qk*) for a given Pk* for the kth H-bridge converter 140-k is given by the Equation (9) as depicted below:
[0042] ------------------------Equation (9)
[0043] In one embodiment, the maximum reactive power processing capability (Qk(max)) of the kth H-bridge for a given Pk*may be determined using Equation (9) above. In one embodiment, consequently, Qk* may be determined using Equation (10) depicted below:
[0044] -------------------------------------------------Equation (10)
[0045] In one embodiment, it may be observed from Equations (9) and (10), the total reactive power demand may be distributed among one or more H-bridges 140-1 to 140-n such that the H-bridge 140, which may be operating with a higher active power value (Pk) may require less reactive power (Qk) for the kth H-bridge to avoid over-modulation.
[0046] In one embodiment, a control architecture for medium voltage AC (MVAC) to multi-port low voltage DC (LVDC) is illustrated in FIGs. 3, 4, and 5. In one embodiment, the individual Vdck loops provide power references Pk*. In one embodiment, the values of vid and viq may be generated from the total active power (Preq = Ʃ Pk*| k= 1, 2, 3…n) and the reactive power (Qreq = Ʃ Qk*| k= 1, 2, 3…n) references.
[0047] In one embodiment, for a given Pk*, Vdck*, iLd*, iLq* and Qreq, Qk* may be determined using Equations (9) and (10) as depicted in FIG. 4. As depicted in FIG. 4, the processor 180 may include a Q* block 410 to determine Q1*, Q2*, ….Qn* based on the values of Pk*, Vdck*, iLd*, iLq* and Qreq, In one embodiment, the PQ controller 510 may determine vidk and viqn, respectively, based on Pk* and Qk* using Equations (6) and (7). In one embodiment, the dq_blocks 510 may generate vidk and viqn upto (n-1) H-bridge converters. In one embodiment, the dq_blocks 510 may generate vidn and viqn for the nth H-bridge converter 140-n, for example, using Equation 2 above for a given vid, viq, vidk|k=1,2,3…. (n-1), and viqk| k=1, 2, 3….(n-1) while satisfying the kirchoff’s voltage law (KVL) depicted in the equation (8).
[0048] In one embodiment, the control technique provided by the PQ controller 187 and the Q distributor 188 may, respectively, support independent PQ control with Q distribution among a plurality of H-bridge converters 140-1 to 140-n. In one embodiment, such an approach may avoid or minimize the over-modulation up to the limit of linear modulation without the need for complex control or harmonic injection. In one embodiment, such a distribution of the reactive power Q improves the utilization range of the H-bridge modules 140-1 to 140-n. In one embodiment, the control techniques described above may be applied to inverters, rectifiers and other such converters. In one embodiment, in the grid-tied inverter applications, active power (Pk*) references may be derived either from the maximum power point tracking (MPPT) controller or a battery management system (BMS).
[0049] FIG. 2 is a flow-chart illustrating the operation of the logic 180 according to an embodiment. In block 210, the power source 170 may provide total active power (P) from a grid based on the load requirement. In one embodiment, the power source may provide a voltage vg to the LCL filter 150, which may generate a combined voltage vi (proportional to the power), which is provided across the plurality of H-bridge converters in the absence of a logic 180 providing the control technique described above.
[0050] In block 240, the processor 182 may receive the total reactive power (Qreq) required value, based on the IEEE 1547 standard. In block 240, the processor 182 may determine the total reactive power (Q) required to support the grid voltage. In one embodiment, the total reactive power (Q) may be determined based on Equations (9) and (10) above. In block 250, the processor 182 may determine vidn and viqn based on the total active and reactive power using Equation (2) shown above. In block 260, the processor 182 may determine Vid and Viq, respectively, based on the total active and reactive power. In block 270, the processor 182 may distribute the total reactive power (Q) among the H-Bridge converters 140-1 to 140-n. In block 280, the processor 182 may determine vidk (individual direct access component of the modulated average voltage) and viqk (individual quadrature access component of the modulated average voltage) as shown in blocks 510 (according to Equations 6 and 7) and 520 (according to Equation 2). In one embodiment, vidn (active parameter) and viqn (reactive parameter) may be provided to each of the plurality of H-bridge converters 140-1 to 140-n. In one embodiment, k denotes individual values ranging from 1 to n provided for each individual H-Bridge converters.
[0051] FIG. 6 depicts a vehicle 620 comprising a battery 650. In one embodiment, the charging or discharging of the battery 650 may be based on the control techniques supported by the system 100 as described above. In one embodiment, the corresponding example waveforms depicting charging of battery 650 through H-bridge 140-1 and 140-n and discharging of the battery 650 through the H-bridges 140-1 and 140-n is depicted in FIG. 7.
[0052] In one embodiment, FIG. 7 (a), (b), and (c) illustrate the responses provided by, for example, H-Bridge converter 140-1 and 140-n, respectively to a step load change while charging the battery 650. In one embodiment, in FIG 7 (a), a step load change 710 is provided to the H-bridge 140-1 and the corresponding responses to the step load change 710 is depicted in the waveforms 712, 714, and 718, respectively. In one embodiment, the waveforms 712, 714, and 718 represent P140-1, Q140-1, and Vdc1, respectively. In one embodiment, in FIG 7 (b), a step load change 720 is provided to the H-bridge 140-n (for example) and the corresponding response to the step load change 720 is depicted in the waveforms 722, 724, and 728, respectively. In one embodiment, the waveforms 722, 724, and 728 represent P140-n, Q140-n, and Vdc2, respectively. Fig. 7 (c) illustrates the waveforms 730 and 738, respectively for vg and ig during the load transition. In one embodiment, the responses 712, 714, and 718 and 722, 724, and 728 illustrate that the active and reactive power of each H-bridge converters is independently controlled. In one embodiment, the reactive power is optimally distributed within the H-Bridge converters 140-1 to 140-n resulting in mitigation of overmodulation.
[0053] In one embodiment, FIG. 7 (d), (e), and (f) illustrate the responses provided by, for example, H-Bridge converter 140-1 and 140-n, respectively to a step load change while discharging the battery 650. In one embodiment, in FIG 7 (d), a load change 710 is provided to the H-bridge 140-1 and the corresponding responses to the step load change 710 is depicted in the waveforms 740, 744, and 748, respectively. In one embodiment, the waveforms 740, 744 and 748 represent P140-1*, P140-1, and Q140-1, respectively. In one embodiment, in FIG 7 (e), a step input 720 is provided to the H-bridge 140-n (for example) and the corresponding responses to the step input 720 is depicted in the waveforms 760. 766, and 768, respectively. In one embodiment, the waveforms 760, 766 and 768 represent P140-n *, P140-n, and Q140-n, respectively. Fig. 7 (f) illustrates the waveforms 770 and 778, respectively for vg and ig during the load transition.
[0054] Embodiments according to the disclosure are in particular disclosed in the attached claims directed to a method, a storage medium, a device and a computer program product, wherein any feature mentioned in one claim category, e.g., method, can be claimed in another claim category, e.g., system, as well. The dependencies or references back in the attached claims are chosen for formal reasons only. However, any subject matter resulting from a deliberate reference back to any previous claims (in particular multiple dependencies) can be claimed as well, so that any combination of claims and the features thereof are disclosed and can be claimed regardless of the dependencies chosen in the attached claims. The subject-matter which can be claimed comprises not only the combinations of features as set out in the attached claims but also any other combination of features in the claims, wherein each feature mentioned in the claims can be combined with any other feature or combination of other features in the claims. Furthermore, any of the embodiments and features described or depicted herein can be claimed in a separate claim and/or in any combination with any embodiment or feature described or depicted herein or with any of the features of the attached claims.
[0055] The foregoing description of one or more implementations provides illustration and description but is not intended to be exhaustive or to limit the scope of embodiments to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of various embodiments.
[0056] Certain aspects of the disclosure are described above with reference to block and flow diagrams of systems, methods, apparatuses, and/or computer program products according to various implementations. It will be understood that one or more blocks of the block diagrams and flow diagrams, and combinations of blocks in the block diagrams and the flow diagrams, respectively, may be implemented by computer-executable program instructions. Likewise, some blocks of the block diagrams and flow diagrams may not necessarily need to be performed in the order presented or may not necessarily need to be performed at all, according to some implementations.
[0057] These computer-executable program instructions may be loaded onto a special-purpose computer or other particular machine, a processor, or other programmable data processing apparatus to produce a particular machine, such that the instructions that execute on the computer, processor, or other programmable data processing apparatus create means for implementing one or more functions specified in the flow diagram block or blocks. These computer program instructions may also be stored in a computer-readable storage media or memory that may direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable storage media produce an article of manufacture including instruction means that implement one or more functions specified in the flow diagram block or blocks. As an example, certain implementations may provide for a computer program product, comprising a computer-readable storage medium having a computer-readable program code or program instructions implemented therein, said computer-readable program code adapted to be executed to implement one or more functions specified in the flow diagram block or blocks. The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational elements or steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions that execute on the computer or other programmable apparatus provide elements or steps for implementing the functions specified in the flow diagram block or blocks.
[0058] Accordingly, blocks of the block diagrams and flow diagrams support combinations of means for performing the specified functions, combinations of elements or steps for performing the specified functions and program instruction means for performing the specified functions. It will also be understood that each block of the block diagrams and flow diagrams, and combinations of blocks in the block diagrams and flow diagrams, may be implemented by special-purpose, hardware-based computer systems that perform the specified functions, elements or steps, or combinations of special-purpose hardware and computer instructions.
[0059] Conditional language, such as, among others, “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain implementations could include, while other implementations do not include, certain features, elements, and/or operations. Thus, such conditional language is not generally intended to imply that features, elements, and/or operations are in any way required for one or more implementations or that one or more implementations necessarily include logic for deciding, with or without user input or prompting, whether these features, elements, and/or operations are included or are to be performed in any particular implementation.
[0060] Many modifications and other implementations of the disclosure set forth herein will be apparent having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the disclosure is not to be limited to the specific implementations disclosed and that modifications and other implementations are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
, Claims:We Claim:
1. A control system comprising:
a memory;
a communications block; and
a processor to determine reactive power (Qk*) components for each of the plurality of H-Bridge converters coupled to a medium voltage alternating current (MVAC) grid.

2. The control system as claimed in claim 1, wherein the processor to determine a total reactive power value based on a rated apparent power.

3. The control system as claimed in claim 2, wherein the processor to determine the total reactive power value as a fraction or percentage (up to 44%) of the rated apparent power.

4. The control system as claimed in claim 3, wherein the processor to determine the total reactive power value as a fraction or percentage (up to 44%) of the rated apparent power based on a standard 1547 (2018), clause 5, set by institute of Electrical and Electronic Engineers (IEEE).

5. The control system as claimed in claim 1, wherein the processor to determine the reactive power (Qk*) component to be provided to each of the plurality (k) of the H-Bridge converters based on the total reactive power value.

6. The control system as claimed in 4, wherein the processor is to determine an average modulated voltage corresponding to each of the reactive power (Qk*) component.

7. The control system as claimed in 5, wherein the processor is to cause the average modulated voltage to be applied across the input of the corresponding H-Bridge converters.

8. The control system as claimed in claim 5, wherein the processor is to cause the average modulated voltage to be provided to the H-Bridge converters independently of the average modulated voltage) provided to the other H-Bridge converters.

9. The control system as claimed in claim 8, wherein the processor is to cause the average modulated voltage to be provided to the H-Bridge converters independently of the average modulated voltage provided to the other H-Bridge converters while a rated active power is drawn from a grid.
10. The control system as claimed in claim 8, wherein the processor is to cause the average modulated voltage to be provided to the H-Bridge converters independently of the average modulated voltage provided to the other H-Bridge converters while a rated active power is supplied to a grid.

11. A method in a control system comprising determining reactive power (Qk*) components, using a processor, for each of the plurality of H-Bridge converters coupled to a medium voltage alternating current (MVAC) grid.

12. The method as claimed in claim 11 includes determining the total reactive power value based on a rated apparent power, using a processor.

13. The method as claimed in claim 12 includes determining the total reactive power value as a fraction or percentage (up to 44%) of the rated apparent power.

14. The method as claimed in claim 13 includes determining the total reactive power value as a fraction or percentage (up to 44%) of the rated apparent power based on a standard 1547 (2018), clause 5, set by institute of Electrical and Electronic Engineers (IEEE).

15. The method as claimed in claim 11 includes determining the reactive power (Qk*) component, which is to be provided to each of the plurality (k) of the H-Bridge converters based on the total reactive power value.

16. The method as claimed in claim 14 includes determining an average modulated voltage corresponding to each of the reactive power (Qk*) component.

17. The method as claimed in claim 15 includes causing the average modulated voltage to be provided to the corresponding H-Bridge converters.

18. The method as claimed in claim 15includes causing the average modulated voltage to be provided to the corresponding H-Bridge converters independently of the average modulated voltage applied across the input of the other H-Bridge converters.

19. The method as claimed in claim 18includes causing the average modulated voltage to be provided to the corresponding H-Bridge converters independently of the average modulated voltage provided to the other H-Bridge converters while a rated active power is drawn from a grid.

20. The method as claimed in claim 18 includes causing the average modulated voltage to be provided to the corresponding H-Bridge converters independently of the average modulated voltage provided to the other H-Bridge converters while a rated active power is supplied to a grid.