With the increase in groundwater exploration, underground mineral resource exploration, and non-destructive investigation of cultural relics, high-resolution earth electrical characteristic measurement has emerged as a mainstream technique owing to its advantageous non-destructive detection capability. To enhance the transmission power of the high-frequency transmitter in high-resolution multiple earth electrical characteristic measurement systems (MECS), this study proposes a high-frequency, high-current transmission technique based on adaptive impedance matching and implemented through the integration of resonant capacitors, a controllable reactor, high-frequency transformers, and corresponding control circuits. A high-current precisely controllable reactor with a 94% inductance variation range was designed and combined with resonant capacitors to reduce circuit impedance. Additionally, high-frequency transformers were employed to further increase the transmission voltage. A prototype was developed and tested, demonstrating an increase in transmission current at frequencies between 10 and 120 kHz with a peak active power of 200 W. Under the same transmission voltage, compared to the transmission circuit without impedance matching, the transmission current increased to a maximum of 16.7 times (average of 10.8 times), whereas compared to the transmission circuit using only traditional impedance matching, the transmission current increased by a maximum of 10.0 times (average of 4.2 times), effectively improving the exploration resolution.

This paper presents a compact, high-efficiency electromagnetic transmitter for Controlled-source Audio-frequency Magnetotelluric (CSAMT) applications, operating in the 10–100 kHz range. A novel bipolar square-wave inverter topology is proposed, which directly modulates the transformer’s secondary-side AC output, eliminating conventional rectification and filtering stages. This design reduces system losses (simulated efficiency > 90%) and achieves an approximately 40% reduction in both volume and weight. The power stage uses a full-bridge bipolar inverter topology with SiC-MOSFETs, combined with a high-frequency transformer for voltage gain. Simulation, laboratory testing, and EMI evaluation confirm stable square-wave generation and full compliance with EN55032 Class A standards. Field validation with a CSAMT receiver demonstrates effective signal transmission and high-resolution subsurface imaging, thereby improving the efficiency and portability of urban geophysical exploration.

Increasing the switching frequency can reduce the size of energy storage components such as the PFC inductor and capacitor, thereby improving power density. However, this also increases switching losses and leads to severe thermal stress. To address this issue, a rectifier-type CRM-PFC circuit based on GaN devices is proposed. The control scheme combines voltage-loop feedback with current-loop feedforward and eliminates the need for zero-current detection (ZCD), enabling stable CRM operation at ultra high frequencies. Based on the proposed control method, Zero-Voltage Switching (ZVS) is achieved across a wide input voltage range.Experimental results show that the proposed PFC circuit achieves a maximum output power of 3.6 kW. The switching frequency spans from 287 kHz to 500 kHz, with a peak efficiency of 97.1% and a power factor exceeding 0.99 under full-load conditions.

Seismic exploration is of significant scientific importance for revealing the geological structure and resource distribution beneath the Antarctic ice sheet. However, existing field instruments face challenges in achieving long-term stable power supply, particularly in the extreme Antarctic environment characterized by severe cold and highly fluctuating renewable energy sources. Conventional energy storage systems struggle with insufficient energy density and performance degradation at low temperatures. To address these issues, this study proposes a hybrid wind-solar power supply system based on a supercapacitor and lithium battery combination, along with a multi-mode cooperative control strategy adapted to low-temperature conditions. The system employs a parallel architecture of photovoltaic panels and vertical-axis wind turbines, integrating constant voltage/constant current control to achieve adaptive energy distribution. Field tests conducted in Antarctica, with over 100 hours of operation, demonstrate that the system achieves a low-temperature startup response time of less than 30 seconds, improves power supply continuity by 7.25 times. The results confirm the system’s capability to reliably support the long-term operation of small distributed seismic acquisition stations in polar regions, demonstrating promising prospects for engineering applications. This research offers novel insights and technical references for the design of energy systems in complex polar environments.