Page 28 - IJOCTA-15-4

M. A. Aman et al. / IJOCTA, Vol.15, No.4, pp.549-577 (2025)
significant advantages due to its inherent flexibil- converter demonstrates superior overall suitabil-
ity in selecting control strategies. However, using ity for SRMs in EV applications.
a greater number of switching devices increases
the cost.
5. Conclusion
4.3.2. Novel integrated power converter
This paper provides a comprehensive review of
The NIPC topology integrates functionalities the state-of-the-art control strategies and power
to reduce the number of active components converter topologies for SRMs in EV applica-
while maintaining adequate performance, thereby tions. Through a detailed examination of torque
achieving a favorable balance between efficiency control techniques, including indirect torque con-
and cost. Despite its integration advantages, trol, DTC, and AI-based control strategies, this
NIPC may face limitations in scalability and ther- study highlights their effectiveness in mitigating
mal management in larger SRM systems. NIPC the drawbacks of SRMs, particularly torque rip-
lowers the costs by requiring fewer devices and en- ple and acoustic noise. Each strategy presents
hancing the reliability of switch reluctance drive distinct advantages and disadvantages, and the
(SRD) systems. Studies indicate that all power choice of technique depends on the desired ap-
devices are susceptible to faults, and the impact plication requirements. However, for EV appli-
of these faults on the operation of NIPC differs. cations, the DITC strategy demonstrates supe-
A short circuit in the capacitor and diodes would rior efficiency in mitigating torque ripple, offering
lead to a short circuit of the power source, result- both ease of implementation and flexibility across
ing in complete power converter failure. Addi- a broad range of torque and speed conditions.
tionally, an open-circuit fault in the diodes would In addition to control techniques, this study
interrupt the release path of stored energy, caus- also explored several power converter topologies
ing overvoltage that can damage the power de- commonly employed in SRM drives, summarizing
vices; hence, the system cannot continue oper- their major advantages and drawbacks. Among
ating under the faulty diode. In contrast, when the various topologies, surveys revealed that the
a battery is chosen as the power source, the re- fault tolerance, rapid demagnetization, and regen-
sponse speed of the DC link is lowered under the erative braking capabilities of the AHB, NIPC,
open-circuit fault of the capacitor; however, the and T-type converters make them particularly
NIPC can still operate. 87 The NIPC topology is suitable for EV applications. The AHB and NIPC
illustrated in Figure 25C. converters offer a favorable cost profile while pro-
viding high efficiency and a significant capacity
4.3.3. T-type converter
for torque ripple reduction. However, their abil-
The T-type converter delivers a compelling com- ity to enhance power productivity remains com-
promise with reduced conduction losses and im- paratively limited. In contrast, the T-type con-
proved efficiency in medium-voltage ranges, posi- verter represents a superior conversion mecha-
tioning it as a strong candidate for EV applica- nism, providing redundant switching states that
tions. However, its control complexity and sensi- enable both magnetization and regenerative de-
tivity to parameter variations necessitate the use magnetization. When paired with a four-phase
of advanced control strategies for optimal opera- SRM, this topology emerges as the most opti-
tion. The T-type converter demonstrates a signif- mal configuration due to its ability to handle high
icant ability to mitigate torque ripple by enabling switching frequencies and reduce switching losses,
simultaneous magnetization and regenerative de- while maintaining excellent fault tolerance and re-
magnetization between two phases. Nonetheless, liability.
its potential for enhancing power productivity re- By synthesizing the available research, this
mains limited due to the limitations imposed by study identifies a four-phase SRM coupled with
magnetization voltage and regenerative demagne- a T-type converter and controlled via DITC as
tization. Besides, it also offers fault-tolerance ca- the most promising configuration for EV applica-
pability. The T-type converter topology is illus- tions, as shown in Figure 27.
trated in Figure 25D. A four-phase SRM is considered, with phases
When comparing the AHB, NIPC, and T-type designated as a, b, c, and d, all of which are ener-
converter topologies, the most suitable choice gized in succession. Shared switches allow the en-
depends on specific design priorities, such as ergization of non-consecutive phases, specifically,
cost, efficiency, fault tolerance, thermal man- phases a and c, while additional shared switches
agement, implementation complexity, and space energize the remaining non-consecutive phases,
constraints. As shown in Figure 26, the T-type namely phases b and d, achieving a high level
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