A new generalized cross-connected switched capacitor multilevel inverter topology with high output voltage gain for single phase solar PV unit

Switched capacitor multilevel inverters are gaining much attention these days due to their merits like voltage boosting and voltage balancing characteristics. A Cross Connected Switched Capacitor Multilevel Inverter (C2SC-MLI) topology is proposed in this work. It can synthesize thirteen levels in the terminal voltage waveform and with a voltage boost ratio of 1:3. The topology is extendable by adding additional “n” modules in series. The number of levels (NLevel) and the voltage gain can be increased up to 4i+9 and 1:(i+2) respectively by connecting ‘i’ such ‘n’ modules. The topology also has inherent voltage balancing ability. To prove the advantage of proposed topology it is compared with recent switched capacitor multilevel inverter topologies and conventional multilevel inverter topologies in terms of number of power electronic components required, cost and voltage gain. The performance of proposed topology is validated using simulation in MATLAB and with an experimental prototype rated 0.1 kW fed by a solar PV emulator under steady state and dynamic loading conditions.

Design of new structure of multilevel inverter based on modified absolute sinusoidal PWM technique

The advantage of multilevel inverters is to produce high output voltage values with distortion as minimum as possible. To reduce total harmonic distortion (THD) and get an output voltage with different step levels using less power electronics switching devices, 15-level inverter is designed in this paper. Single-phase 11-switches with zero-level (ZL) and none-zero-level (NZL) inverter based on modified absolute sinusoidal pulse width modulation (MASPWM) technique is designed, modelled and built by MATLAB/Simulink. Simulation results explained that, multilevel inverter with NZL gives distortion percent less than that with ZL voltage. The THD of the inverter output voltage and current of ZL are 4% and 1%, while with NZL is 3.6% and 0.84%, respectively. These results explain the effectiveness of the suggested power circuit and MASPWM controller to get the required voltage with low THD.

All-in-One High-Power-Density Vibrational Energy Harvester with Impact-Induced Frequency Broadening Mechanisms

This paper proposes an electrostatic-piezoelectric-electromagnetic hybrid vibrational power generator with different frequency broadening schemes. Both the nonlinear frequency broadening mechanisms and the synergized effect of the electrostatic-piezoelectric-electromagnetic hybrid structures are investigated. The structure and performance of the composite generator are optimized to improve the response bandwidth and performance. We propose that the electrostatic power generation module and the electromagnetic power generation module be introduced into the cantilever beam to make the multifunctional cantilever beam, realizing small integrated output loss, high output voltage, and high current characteristics. When the external load of the electrostatic power generation module is 10 kΩ, its peak power can reach 3.6 mW; when the external load of the piezoelectric power generation module is 2 kΩ, its peak power is 2.2 mW; and when the external load of the electromagnetic power generation module is 170 Ω, its peak power is 0.735 mW. This means that under the same space utilization, the performance is improved by 90%. Moreover, an energy management circuit (ECM) at the rear end of the device is added, through the energy conditioning circuit, the device can directly export a 3.3 V DC voltage to supply power to most of the sensing equipment. In this paper, the hybrid generator’s structure and performance are optimized, and the response bandwidth and performance are improved. In general, the primary advantages of the device in this paper are its larger bandwidth and enhanced performance.

A Compact High-Performance 10-bit 30-Channel OLED Driver Using Switched Capacitor Circuit for High-Linearity Application

This work proposes a new OLED driver architecture with 10-bit segmented DAC and switched capacitor multiply-by-two circuit application. A 30-channel 10-bit switched capacitor driver chip prototype is implemented in 0.18-[Formula: see text]m CMOS technology. In this architecture, the achieved output range is 1.5–4.8[Formula: see text]V for an input range of 1.5–3.15[Formula: see text]V, which is suitable for OLED driver with different colors. This architecture is not only converting the digital input signal to analog output for the display panel but also giving amplified high output voltage range. In the segmented DAC, 6-bit coarse DAC and 4-bit fine DAC are used for the input voltage range 1.5–3.15[Formula: see text]V. In a conventional RDAC for the output voltage of 4.8[Formula: see text]V, it requires 2[Formula: see text] switches i.e., 14-bit RDAC for the same resolution. Hence, conventional RDAC driver is four times larger than the proposed innovative very compact and high speed 10-bit segmented DAC switched capacitor OLED driver. The new architecture drastically reduces the number of switches and complex metal routing which results in reduced power consumption and good settling time. In the proposed OLED driver, no extra buffer is required as switched capacitor op-amp is applied for the same purpose with a gain of more than one. This high-resolution design with small die area also improves the linearity and uniformity with low-power consumption. The post-simulated results show that the OLED driver exhibits the maximum DNL and INL of 0.03 LSB and [Formula: see text]0.06 LSB, respectively, with an LSB voltage of 3[Formula: see text]mV. The one-channel area is 0.586[Formula: see text]mm [Formula: see text] 0.017[Formula: see text]mm and the settling time is 4.25[Formula: see text][Formula: see text]s for 30[Formula: see text]k[Formula: see text] and 30[Formula: see text]pF driving load.

Design and Implementation of Multilevel Inverter with Various MPPT Algorithms for Optimal Tracking of PV System

In this paper the different algorithm is performed in MATLAB Simulink to extract large amounts of energy from the pv system. MPPT algorithm is used to reduce complexity and to get better results, we used to perturb and observation, incremental conductance and fuzzy logic algorithm. A three-phase NPC inverter is used to connect the PV array with grid system, The PWM control method is used for the producing the PWM inverter signals. it contains PV array, dc / dc boost, three level NPC inverter. To get the synchronization between PV system and grid the synchronous reference frame theory with PLL block is used. The SRF theory will transform the three phase load currents (ia, ib, ic) to the two instantaneous active (id) and reactive (iq) components. The MATLAB simulation is preformed and we get a constant high output voltage from low input voltage and by changing the irradiance and temperature.

Starter for Voltage Boost Converter to Harvest Thermoelectric Energy for Body-Worn Sensors

This paper examines the suitability of selected configurations of ultra-low voltage (ULV) oscillators as starters for a voltage boost converter to harvest energy from a thermoelectric generator (TEG). Important properties of particularly promising configurations, suitable for on-chip implementation are compared. On this basis, an improved oscillator with a low startup voltage and a high output voltage swing is proposed. The applicability of n-channel native MOS transistors with negative or near-zero threshold voltage in ULV oscillators is analyzed. The results demonstrate that a near-zero threshold voltage transistor operating in the weak inversion region is most advantageous for the considered application. The obtained results were used as a reference for design of a boost converter starter intended for integration in 180-nm CMOS X-FAB technology. In the selected technology, the most suitable transistor available with a negative threshold voltage was used. Despite using a transistor with a negative threshold voltage, a low startup voltage of 29 mV, a power consumption of 70 µW, and power conversion efficiency of about 1.5% were achieved. A great advantage of the proposed starter is that it eliminates a multistage charge pump necessary to obtain a voltage of sufficient value to supply the boost converter control circuit.

Adaptive and Robust Operation with Active Fuzzy Harvester under Nonstationary and Random Disturbance Conditions

The objective of this paper is to amplify the output voltage magnitude from a piezoelectric vibration energy harvester under nonstationary and broadband vibration conditions. Improving the transferred energy, which is converted from mechanical energy to electrical energy through a piezoelectric transducer, achieved a high output voltage and effective harvesting. A threshold-based switching strategy is used to improve the total transferred energy with consideration of the signs and amplitudes of the electromechanical conditions of the harvester. A time-invariant threshold cannot accomplish effective harvesting under nonstationary vibration conditions because the assessment criterion for desirable control changes in accordance with the disturbance scale. To solve this problem, we developed a switching strategy for the active harvester, namely, adaptive switching considering vibration suppression-threshold strategy. The strategy adopts a tuning algorithm for the time-varying threshold and implements appropriate intermittent switching without pre-tuning by means of the fuzzy control theory. We evaluated the proposed strategy under three realistic vibration conditions: a frequency sweep, a change in the number of dominant frequencies, and wideband frequency vibration. Experimental comparisons were conducted with existing strategies, which consider only the signs of the harvester electromechanical conditions. The results confirm that the presented strategy achieves a greater output voltage than the existing strategies under all nonstationary vibration conditions. The average amplification rate of output voltage for the proposed strategy is 203% compared with the output voltage by noncontrolled harvesting.

Manipulating anion intercalation enables a high-voltage aqueous dual ion battery

Aqueous graphite-based dual ion batteries have unique superiorities in stationary energy storage systems due to their non-transition metal configuration and safety properties. However, there is an absence of thorough study of the interactions between anions and water molecules and between anions and electrode materials, which is essential to achieve high output voltage. Here we reveal the four-stage intercalation process and energy conversion in a graphite cathode of anions with different configurations. The difference between the intercalation energy and hydration energy of bis(trifluoromethane)sulfonimide makes the best use of the electrochemical stability window of its electrolyte and delivers a high intercalation potential, while BF4− and CF3SO3− do not exhibit a satisfactory potential because the graphite intercalation potential of BF4− is inferior and the graphite intercalation potential of CF3SO3− exceeds the voltage window of its electrolyte. An aqueous dual ion battery based on the intercalation behaviors of bis(trifluoromethane)sulfonimide anions into a graphite cathode exhibits a high voltage of 2.2 V together with a specific energy of 242.74 Wh kg−1. This work provides clear guidance for the voltage plateau manipulation of anion intercalation into two-dimensional materials.