Accurate detection of internal partial discharge (PD) in gas-insulated switchgear (GIS), a core component of modern power systems, is crucial for assessing insulation condition, ensuring equipment reliability, and maintaining power grid stability. However, the practical application of traditional ultra-high frequency (UHF) electromagnetic sensors in GIS condition-based maintenance faces significant limitations, including severe signal attenuation (20～40 dB/m) caused by the metal enclosure, the risk of SF6 leakage due to compromised airtightness with window-based installation, and a limited dynamic range (60～80 dB) insufficient for covering the full range of discharge magnitudes. To overcome these technical bottlenecks, this paper innovatively proposes a quantum-based UHF electric field sensing method utilizing the Rydberg atomic electromagnetically induced transparency (EIT) effect. The core advantages of this method lie in: leveraging the extremely high electric polarizability of highly excited cesium atoms (n=72D5/2) to achieve intrinsically safe measurement through an optical readout mechanism; establishing a stable EIT window using a dual-frequency laser system (852 nm probe light and 509 nm pump light) combined with precise frequency-locking technology; and designing a non-metallic atomic vapor cell antenna to realize the first near-field sensing of transient pulse electric fields in the 0.5～3 GHz band excited by particle discharge within GIS. This research demonstrates the capability of Rydberg atomic sensing technology to effectively detect discharges from a typical GIS defect (metal particles) for the first time. By employing quantum precision measurement, it provides a novel optical fiber sensing solution characterized by high sensitivity, broadband capability, and intrinsic safety for the online insulation monitoring of power equipment. This approach holds significant promise for advancing condition-based maintenance towards intelligent and precise evolution, offering key supporting technologies for the development of smart grids.
Accurate detection of internal partial discharge (PD) in gas-insulated switchgear (GIS), a core component of modern power systems, is crucial for assessing insulation condition, ensuring equipment reliability, and maintaining power grid stability. However, the practical application of traditional ultra-high frequency (UHF) electromagnetic sensors in GIS condition-based maintenance faces significant limitations, including severe signal attenuation (20～40 dB/m) caused by the metal enclosure, the risk of SF6 leakage due to compromised airtightness with window-based installation, and a limited dynamic range (60～80 dB) insufficient for covering the full range of discharge magnitudes. To overcome these technical bottlenecks, this paper innovatively proposes a quantum-based UHF electric field sensing method utilizing the Rydberg atomic electromagnetically induced transparency (EIT) effect. The core advantages of this method lie in: leveraging the extremely high electric polarizability of highly excited cesium atoms (n=72D5/2) to achieve intrinsically safe measurement through an optical readout mechanism; establishing a stable EIT window using a dual-frequency laser system (852 nm probe light and 509 nm pump light) combined with precise frequency-locking technology; and designing a non-metallic atomic vapor cell antenna to realize the first near-field sensing of transient pulse electric fields in the 0.5～3 GHz band excited by particle discharge within GIS. This research demonstrates the capability of Rydberg atomic sensing technology to effectively detect discharges from a typical GIS defect (metal particles) for the first time. By employing quantum precision measurement, it provides a novel optical fiber sensing solution characterized by high sensitivity, broadband capability, and intrinsic safety for the online insulation monitoring of power equipment. This approach holds significant promise for advancing condition-based maintenance towards intelligent and precise evolution, offering key supporting technologies for the development of smart grids.
Abstract Partial discharge (PD) detection has garnered considerable attention due to its critical role in condition assessment and fault prediction of power system equipment. However, efficient and accurate acquisition of PD signals remains a significant technical challenge. Among mainstream technologies, the ultra-high frequency (UHF) detection method plays a key role in capturing PD signals. This work introduces a Rydberg atom-based electric field sensing approach for PD detection, employing a three-photon excitation scheme in cesium vapor. Four representative PD types are investigated: void, floating, particle, and corona, revealing the ability of the nonmetallic atomic sensor to capture their distinct time-domain characteristics and periodic behaviors at the power frequency. In addition, an antenna–waveguide–vapor cell coupling configuration is proposed. This electro-optical to opto-electronic conversion mechanism allows the sensor to achieve long-range detection while preserving favorable signal-to-noise ratios. Although the sensor’s limited instantaneous bandwidth leads to pulse broadening in high-speed signals, its theoretical high sensitivity and wide operating bandwidth highlight its potential as a complement to traditional metal-antenna solutions. These findings provide a robust foundation for implementing quantum-enhanced PD monitoring in practical power engineering scenarios.
Rydberg-assisted atomic electrometry with thermal vapors offers a promising approach for detecting external electric fields. However, this technique presents significant challenges for measuring low frequencies due to the effects of metal-alkali atoms adsorbed on the interior surface of the vacuum chamber. In this work, we apply high-contrast Rydberg electromagnetically induced transparency (EIT) spectroscopy to systematically investigate these effects, including the influence of laser power and electric field strength. We demonstrate the ability to measure electric field frequencies ranging from 10 Hz to 1 MHz. Additionally, this study identifies a fundamental limit for data capacity in such measurements. Furthermore, we propose a method for precise Stark shift measurements by locking the coupling laser to Zeeman-split Rydberg EIT peaks. Using the Zeeman shift in a reference cell as a stable frequency reference, we are able to track Stark-induced shifts in a science cell and confirm excellent agreement with theoretical predictions. These results provide valuable insights for future precision measurement techniques and field sensing applications based on Rydberg atom systems.
Rydberg atoms are neutral atoms excited to high principal quantum number states, which endows them with exaggerated properties such as large electric dipole moments, long lifetimes, and extreme sensitivity to external electromagnetic fields. These characteristics form the foundation of Rydberg atom-based sensors, an emerging class of quantum devices capable of optically detecting electric fields across frequencies from DC to the terahertz regime. Rydberg-based electrometry operates through both Autler–Townes (AT) splitting of resonant Rydberg transitions and Stark-shift measurements for high-frequency or far-detuned fields, enabling broadband field sensing from DC to the THz regime. Using ladder-type electromagnetically induced transparency (EIT) and AT splitting, these sensors enable non-invasive, SI-traceable measurements of field amplitude, frequency, phase, and polarization. Recent developments have demonstrated broadband electric field probes, voltage calibration standards, and compact RF receivers based on thermal vapor cells and integrated photonic architectures. Furthermore, innovations in multi-photon EIT, superheterodyne readout, and multi wave mixing have expanded the dynamic range and bandwidth of Rydberg-based electrometry. Despite challenges related to environmental perturbations, linewidth broadening, and laser stabilization, ongoing advances in atomic control, hybrid photonic integration, and EIT-based readout promise scalable, chip-compatible sensors. This review summarizes the physical principles, experimental progress, and emerging applications of Rydberg atom-based sensing, emphasizing their potential for next generation quantum metrology, wireless communication, and precision field mapping.
Significant progress has been made in atom-based measurements of length, time, gravity and electromagnetic fields in recently years. Rydberg atom-based microwave electric field measurement, using electromagnetically induced transparency (EIT) in room temperature alkali-metal vapors, has been extensively investigated and aroused the broad interest. This approach may establish a new standard for the measurements of microwave (MW) and radio frequency (RF) electric fields.In this review, we describe the work on a new method of measuring electric fields based on quantum interference by using either cesium or rubidium atoms contained in a dielectric vapor cell. Rydberg atoms with principal quantum number n >>1 have large direct current (DC) polarizabilities and microwave transition dipole moments, thereby making them extremely sensitive to external electric fields. Using the Rydberg three-level EIT to detect the level splitting and shift that is induced by the external field, we can realize a rapid and robust self-calibration method of measuring the electric field in a frequency range from 0.01 GHz to 1000 GHz. For the MW electric field (frequency range > 1 GHz), the MW field causes the Rydberg states to split, known as an Autler-Townes splitting (A-T) effect when the applied microwave can resonate with adjacent Rydberg states. The MW coupled A-T splitting is proportional to the applied electric field strength, from which the field strength is measured. Using the EIT window, a high sensitivity of 3 μV·cm-1·Hz-1/2 and small electric field of 1 μV/cm are expected to be achieved with a modest setup, and the limitations of the sensitivity are also addressed in the review. For the RF field at frequency mj EIT lines, and avoided crossings formed with the fine-structure levels of equal mj and different J's, which is used to calibrate and measure the RF field amplitude. On the other hand, the dependence of the EIT-line strength on the RF field polarization provides a fast and robust polarization measurement of RF fields based on matching experimental data with a theoretical simulation. The measurements of minimum strengths and sensitivity of RF fields based on Rydberg atoms are one order magnitude below the values obtained by traditional antenna methods. The atom-based field measurement paves the way for determining fields through calibration-free, invariable atomic properties and miniaturization. We also propose its various potential applications in the future.
Rydberg atom electric field sensing technology shows great potential for power system frequency electric field measurement but faces mechanical vibration interference when moving from laboratory to on-site applications. To address this bottleneck, a compact Rydberg atom optical path system was constructed: the cesium atomic vapor cell for measurement was fiber-connected to enable flexible fixation of the sensing unit, and key optical components were configured to optimize the Electromagnetically Induced Transparency (EIT) effect. Experiments were conducted to analyze the effects of vibrations applied in directions parallel and perpendicular to the optical path on EIT Spectral, both with and without DC electric field dressing. Experimental observations reveal distinct impacts of vibrations along the two directions, and in both cases the intensity of vibration-induced effects scales with increasing frequency and amplitude. Despite periodic baseline fluctuations observed under vibrations in either direction, no frequency shifts of the EIT Spectral were detected across all experiments. This confirms the excellent anti-vibration performance of the proposed Rydberg cesium atom electric field sensing system, providing theoretical support for its on-site application in power systems.
Rydberg atoms, which possess exceptionally large electric dipole moments, offer a promising route for electric field sensing as well as metrology traceable to the International System of Units (SI); however, current research predominantly focuses on the microwave (MW) regime, leaving the quasi-direct current (quasi-DC) and low-frequency bands, ubiquitous in power systems, largely unexplored. In this paper, we present a theoretical investigation into low-frequency electric field detection. To this end, we establish a comprehensive modeling framework incorporating Fisher information (FI) and the Cramér-Rao lower bound (CRLB) to quantify the fundamental precision limits of electromagnetically induced transparency (EIT) readouts. Building upon this framework, we propose a linearized sensing strategy utilizing a DC-biased two-point differential measurement. Numerical validations demonstrate that this approach effectively mitigates the weak-field insensitivity for both DC and AC fields, achieving a CRLB-limited sensitivity bound of approximately 1×10−4 V/m/Hz. Furthermore, to surpass the single-pass sensitivity limit, we introduce a Fabry-Pérot (FP) cavity-enhanced configuration. This architecture leverages intracavity phase modulation to significantly steepen the transmission slope, boosting the FI by over two orders of magnitude compared to standard free-space configurations. This work provides a rigorous theoretical basis and design guidance for the high-precision quantum monitoring of electromagnetic environments in smart grids.