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The control of dual active bridge series resonant converter (DABSRC) has been widely researched in the literature for various applications, including pulsed-power-load (PPL). Numerous phase-shift and frequency modulation schemes help DABSRC achieve output voltage regulation along with reactive power control. In case of PPL applications, a fast and uniform transient response is desired for both the output voltage and the reactive power in the high-frequency link due to frequent loading. This requirement is broadly fulfilled through linearized and nonlinear control methods. A large-signal model-based control (LSMC) is proposed in this article, which achieves a uniform transient response throughout the operating range, unlike the small-signal model-based linearized multivariable control. The proposed LSMC method eliminates the operating point dependency through a lucid control methodology combining analog and digital blocks. The decoupling in multivariable control and system order reduction is achieved through the feedforward technique. This method also reduces the computational burden time of the controller as compared to the existing nonlinear control methods. The achieved settling time for both output voltage and reactive power is $\text{5}\; \text{ms}$ with a computational burden of $\text{5.6}\; \mu \text{s}$. The experimental validations are performed on a $\text{2.4} \; \text{kW}$ DABSRC hardware prototype.

One of the significant disadvantages of high frequency power electronics converter is its Electromagnetic Compatibility(EMC). The converters must meet different Electromagnetic interference(EMI) standards, i.e., CISPR, and IEC set by various international bodies for commercialization. Low frequency (150 kHz-2 MHz) conducted emission noise is due to switching harmonics of the converters. High values of high frequency DC bus capacitor are used to reduce Differential Mode (DM) noise. Such high values of DC bus capacitors make the converter bulky. Also, these DC bus capacitors should have a high Self Resonating Frequency (SRF) to absorb DM noise of frequency range 500 kHz-2 MHz. Finding such high value capacitors with high SRF is very much challenging. The present article presents a dithering technique that is very simple to implement in hardware and passes CISPR standards with a minimal amount of DC bus capacitors without compromising the efficiency of the converter. A DC-DC buck converter has been used in this paper for validating the proposed dithering technique. Resolution Band Width (RBW) has been taken 9 kHz while measuring the noise, as per CISPR-11 standards and the proposed technique has been modified according to 9 kHz RBW.

Voltage angle-based torque control of dual three-phase interior permanent magnet synchronous machines (DTP-IPMSMs) in the field weakening (FW) region offers maximum dc voltage utilization, increased speed range, and higher torque capability. However, the difference in parameter values between the two three-phase winding sets results in torque limitations during FW operation. This article considers a dual three-phase IPMSM with 0$^\circ$ winding displacement (DTP0 IPMSM), where the resistance and leakage inductance of each three-phase winding set are not the same. The effect of this parameter mismatch on the FW performance is discussed in detail. Further, a control scheme is proposed, where a 2-pole torque controller controls the torque dynamics by modifying the voltage angle of one of the inverters, while the other inverter's voltage angle is controlled to minimize the effect of parameter mismatch. The proposed method is implemented on a 3.68 kW DTP0 IPMSM prototype. For a given torque, the current requirement is shown to reduce approximately by 4% in the low and midspeed ranges of the FW region when compared with existing approaches of DTP0 IPMSM control. The performance of the 2-pole controller is also demonstrated, which achieves the desired control system specifications.

Power electronics converters have to meet international electromagnetic compatibility (EMC) standards, i.e., CISPR, IEC for commercial application. Electromagnetic interference (EMI) filters are generally used with converters to meet the standards. These EMI filters are heavy, expensive, and space consuming. A dithering technique of switching frequency has been proposed in this article to reduce the conducted EMI. The proposed technique accurately predetermines the exact reduction of noise. This article also illustrates the problem of resolution bandwidth (RBW) in power electronics applications while measuring the noise. Thus, the present article also suggests a modified dithering technique to overcome this problem. Experimental results are presented at different RBW in the present article. The proposed dithering technique and its modification have been validated through a SiC mosfet-based voltage source inverter fed drive. This article also focuses on the advantages of reducing common mode choke and dc bus capacitance, which eventually saves space and cost for the entire converter system.