Partial discharge probe based on Rydberg atoms

Abstract

The invention provides a Rydberg atom-based partial discharge probe. The Rydberg atom-based partial discharge probe comprises a protective shell, a resonant cavity assembly, a light leading-in assembly and a light leading-in and leading-out assembly, the resonant cavity assembly is arranged in the protective shell; the detection light incidence assembly is arranged on one outer side of the resonant cavity assembly and is in optical communication connection with the interior of the resonant cavity assembly; the light leading-in and leading-out assembly is arranged on the other outer side of the resonant cavity assembly and is in optical communication connection with the interior of the resonant cavity assembly, and the probe light emitted by the light leading-in assembly penetrates through the interior of the resonant cavity assembly and then enters the light leading-in and leading-out assembly; pump light emitted by the light leading-in and leading-out assembly passes through the interior of the resonant cavity assembly and goes back and forth in the resonant cavity for multiple times, and resonant cavity resonance enhancement is formed. Resonance enhancement in the resonant cavity is combined with detection light out-of-cavity design, so that the light field absorption efficiency of the partial discharge probe is improved, and the power requirement of a laser light source is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of discharge detection, and in particular to a partial discharge probe based on Rydberg atoms. Background Art

[0002] Partial discharge detection technology based on Rydberg atoms utilizes the high sensitivity of Rydberg atoms to electromagnetic fields. This new detection technology achieves discharge location and intensity measurement by detecting changes in the electromagnetic field generated by partial discharge. It offers advantages such as high sensitivity and non-contact detection. To achieve sufficient atomic excitation rates, existing partial discharge probes typically require high-power laser light sources exceeding 100mW, resulting in power accumulation issues such as reliance on external power input and high spontaneous emission noise. Furthermore, the single-pass absorption rate of pump light by partial discharge probes is less than 10%, leaving a significant amount of optical power unutilized. This also leads to large system size and high power consumption, perturbations of the atomic ensemble caused by strong laser-induced thermal effects, and mode degradation of semiconductor lasers above 50mW. Therefore, improving partial discharge probes to increase their optical field absorption efficiency while reducing the laser power is a technical challenge that needs to be addressed. Summary of the Invention

[0003] The present invention provides a partial discharge probe based on Rydberg atoms. By combining resonance enhancement in a resonant cavity with a design of detecting light leaving the cavity, the light field absorption efficiency of the partial discharge probe is improved and the power requirement of the laser light source is reduced.

[0004] The technical solutions provided by the present invention are as follows: A partial discharge probe based on Rydberg atoms, comprising: A protective shell, the protective shell is a cavity structure; A resonant cavity component, wherein the resonant cavity component is built into the protective shell; The light introduction component and the detection light incident component are arranged outside the resonant cavity component and are connected to the inside of the resonant cavity component through optical communication; The light introduction and extraction component is arranged on the other outer side of the resonant cavity component and is connected to the interior of the resonant cavity component through optical communication. The detection light emitted by the light introduction and extraction component passes through the interior of the resonant cavity component and is incident on the light introduction and extraction component; the pump light emitted by the light introduction and extraction component passes through the interior of the resonant cavity component and travels back and forth inside the resonant cavity multiple times, forming resonant cavity resonance enhancement.

[0005] Preferably, the resonant cavity assembly includes: The cesium atomic gas chamber is located in the middle of the internal cavity structure of the protective shell; a first high-reflection and high-transmission mirror, which is arranged between the cesium atom gas chamber and the light introduction component, and the detection light emitted by the light introduction component is incident on the cesium atom gas chamber; a second high-reflection and high-transmission mirror, which is disposed between the cesium atom gas chamber and the light introduction and extraction assembly and forms a resonant cavity with the first high-reflection and high-transmission mirror. The pump light emitted from the light introduction and extraction assembly passes through the second high-reflection and high-transmission mirror and is incident on the cesium atom gas chamber; The dichroic mirror is arranged on the outside of the second high-reflection and high-transmission mirror. The detection light emitted by the cesium atomic gas chamber is transmitted into the cesium atomic gas chamber through the first high-reflection and high-transmission mirror, and then transmitted to the dichroic mirror through the second high-reflection and high-transmission mirror; the pump light reflected by the dichroic mirror is parallelly projected to the cesium atomic gas chamber through the second high-reflection and high-transmission mirror.

[0006] The present invention uses a resonant cavity composed of a first high-reflection and high-transmission mirror and a second high-reflection and high-transmission mirror arranged in parallel and a cesium atomic gas chamber to allow only pump light of a specific frequency to form a stable standing wave in the cavity, while light of other frequencies is suppressed due to interference destructive phase, thereby achieving the purpose of resonant cavity frequency selection.

[0007] Preferably, the second high-reflection and high-transmission mirror and the first high-reflection and high-transmission mirror are symmetrically arranged on both sides of the axis of the cesium atomic gas chamber, and the pump light transmitted by the second high-reflection and high-transmission mirror is parallel to the detection light and irradiated into the cesium atomic gas chamber; the pump light emitted by the cesium atomic gas chamber is reflected by the first high-reflection and high-transmission mirror and then passes through the cesium atomic gas chamber again and then reaches the second high-reflection and high-transmission mirror, thereby passing through the interior of the cesium atomic gas chamber many times and irradiating the detection light many times in the cesium atomic gas chamber in parallel, forming a resonant cavity resonance enhancement.

[0008] Preferably, the resonant cavity assembly further comprises: A third high-reflection and high-transmission mirror is arranged opposite to the first high-reflection and high-transmission mirror, and the pump light emitted from the cesium atomic gas chamber is incident on the first high-reflection and high-transmission mirror and is reflected by the first high-reflection and high-transmission mirror to the third high-reflection and high-transmission mirror; The fourth high-reflection and high-transmission mirror is arranged opposite to the third high-reflection and high-transmission mirror and the second high-reflection and high-transmission mirror. The pump light emitted by the first high-reflection and high-transmission mirror is reflected by the third high-reflection and high-transmission mirror to the fourth high-reflection and high-transmission mirror, and then reflected by the fourth high-reflection and high-transmission mirror to the second high-reflection and high-transmission mirror.

[0009] The pump light transmitted by the second high-reflection and high-transmission mirror is incident on the cesium atomic gas chamber in parallel with the detection light; the pump light emitted by the cesium atomic gas chamber is reflected by the first high-reflection and high-transmission mirror, the third high-reflection and high-transmission mirror, the fourth high-reflection and high-transmission mirror, and the second high-reflection and high-transmission mirror in sequence into the cesium atomic gas chamber, thus going back and forth between the four high-reflection and high-transmission mirrors many times and incident on the detection light in parallel many times in the cesium atomic gas chamber, forming a resonant cavity resonance enhancement.

[0010] The present invention uses the resonant cavity resonance enhancement mode. When the pump light frequency matches the resonant cavity resonance frequency, the pump light residence time in the resonant cavity is increased, the photon lifetime is prolonged, and the light field intensity in the cavity is much higher than the incident light intensity, thereby achieving the purpose of resonant cavity energy storage.

[0011] Preferably, the light introduction component includes: The first collimator is arranged outside the first high-reflection and high-transmission mirror. The detection light emitted by the first collimator is transmitted to the cesium atomic gas chamber through the first high-reflection and high-transmission mirror.

[0012] Preferably, the light introduction and extraction components include: A second collimator is provided between the dichroic mirror and the second high-reflection and high-transmission mirror and is symmetrical to the first collimator.

[0013] The present invention enables detection light to be emitted from a first collimator and pass through a cesium atomic gas chamber once. It does not directly participate in the light field oscillation in the resonant cavity, but instead achieves high-sensitivity, wide-band, and low-interference detection through coupling with the light field in the cavity. Then, after passing through a second high-reflection and high-transmittance mirror and a second collimator, it is transmitted through a dichroic mirror and output to a photoelectric detection module to complete signal reading and detect the EIT transmission spectrum signal. This achieves complete isolation of the detection light from the pump light in the resonant cavity in terms of space and optical path, realizes an off-cavity design of the detection light, avoids the frequency restriction of the resonant cavity on the detection light, and reduces cavity losses and nonlinear effects.

[0014] Preferably, the partial discharge probe further comprises: The photoelectric detection module is arranged outside the resonant cavity component. The detection light emitted by the light introduction and extraction component is incident on the photoelectric detection module. The photoelectric detection module detects the electromagnetic induced transparent spectrum signal in the detection light and converts it into an electrical signal.

[0015] Preferably, the control system includes a temperature control module and a light intensity control module; The temperature control module includes: A temperature sensor is built into the resonant cavity and is used to monitor the resonant cavity and its internal temperature in real time, generate a voltage signal and output it to the temperature control unit; A temperature control unit is communicatively connected to the temperature sensor, configured to receive a voltage signal from the temperature sensor, compare the measured temperature with the target temperature, generate a temperature error signal, and drive the temperature control components to operate; The temperature control component is in communication with the temperature control unit and is used to adjust the resonant cavity and its internal temperature in real time according to the temperature error signal sent by the controller module.

[0016] The light intensity control module includes: A power coupler, which is built into the resonant cavity and is used to convert the real-time sampled pump light intensity passing through the resonant cavity into a voltage signal and output it to the light intensity control unit; A light intensity control unit is communicatively connected to the power coupler, configured to receive an electrical signal from the power coupler, calculate a light intensity error signal using a PID algorithm, and generate a light intensity drive signal; PZT piezoelectric ceramic, the PZT piezoelectric ceramic is arranged on the first high-reflection and high-transmission mirror or the fourth high-reflection and high-transmission mirror, and is communicated with the light intensity control unit, and is used to generate displacement according to the received driving signal, adjust the distance between the first high-reflection and high-transmission mirror and the second high-reflection and high-transmission mirror, and realize cavity length frequency locking; or adjust the relative distance between the fourth high-reflection and high-transmission mirror and the first high-reflection and high-transmission mirror, the second high-reflection and high-transmission mirror, and the third high-reflection and high-transmission mirror.

[0017] The present invention implements a temperature-piezoelectric composite tuning mechanism through a control system, controlling the frequency drift of the resonant cavity within 100kHz, ensuring that the 509nm detection light is always in a resonant state and improving the stability of the resonant cavity. At the same time, the frequency drift is less than 100kHz, improving the frequency locking accuracy of the resonant cavity. The light intensity enhancement factor is stabilized at 5 to 10 times, suppressing the influence of environmental noise such as temperature drift and mechanical vibration on the resonant cavity.

[0018] The present invention integrates the system volume into a small resonant cavity through a signal enhancement mechanism that combines resonant cavity energy storage with quantum coherence effect enhancement. The structure is compact, vacuum noise is compressed, and the signal-to-noise ratio is high, thereby achieving light field compression.

[0019] The present invention introduces the principle of cavity quantum electrodynamics into the partial discharge atomic probe. By combining the resonant cavity with the detection light off-cavity design, the "light field compression" replaces the "power stacking" in the existing technology. By generating a compressed vacuum state to reduce the light field noise, the detection sensitivity can be achieved or even exceeded that of traditional power stacking at a lower power laser, achieving a higher signal-to-noise ratio.

[0020] The present invention avoids the limitation of large-size resonant cavities by adopting an off-cavity design in which the detection light does not participate in the oscillation inside the resonant cavity, thus opening up a new path for the miniaturization of quantum sensors. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 1 is a schematic structural diagram of a partial discharge probe based on Rydberg atoms according to the first embodiment of the present invention; Figure 2This is a schematic structural diagram of a partial discharge probe based on Rydberg atoms according to a second embodiment of the present invention; wherein 1 is a dichroic mirror; 2 is a partial discharge probe; 3 is a second high-reflection and high-transmission mirror; 4 is a first high-reflection and high-transmission mirror; 5 is a cesium atom gas chamber; 6 is a PZT piezoelectric ceramic; 7 is a first collimator; 8 is a second collimator; 9 is a third high-reflection and high-transmission mirror; and 10 is a fourth high-reflection and high-transmission mirror. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solutions in this application, the following will clearly and completely describe the technical solutions in the embodiments of this application in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application. Example

[0023] As attached Figure 1 As shown, the first embodiment of the present invention provides a partial discharge probe based on Rydberg atoms, including a protective shell, a resonant cavity component, a light introduction component and a light introduction and extraction component.

[0024] The resonant cavity assembly includes a cesium atomic gas chamber 5 , a first high-reflection and high-transmission mirror 4 , a second high-reflection and high-transmission mirror 3 and a dichroic mirror 1 .

[0025] The first high-reflection and high-transmission mirror 4 responds to the detection light with high transmission and responds to the pump light with high reflection. The second high-reflection and high-transmission mirror 3 responds to the detection light with high transmission and responds to the pump light with high reflection and low transmission. The wavelength of the detection light is preferably 852.35 nm, which is used to excite cesium atoms from the ground state 6S 1 / 2 Transition to the first excited state 6P 3 / 2 The wavelength of the pump light should be less than or equal to 509.53 nm. In this embodiment, the wavelength of the pump light is preferably 509.53 nm, which is used to excite cesium atoms from the first excited state 6P 3 / 2 Transition to a Rydberg state with a principal quantum number greater than 50.

[0026] The resonant cavity can allow a small portion of the pump light to pass through the second high-reflection and high-transmission mirror 3 into the resonant cavity, and reflect most of the pump light to maintain oscillation in the cavity. The reflectivity of the resonant cavity to the pump light is greater than 99.98%, and the transmittance is less than or equal to 0.02%; the transmittance of the resonant cavity to the detection light for a single pass is greater than 95%. The pump light transmitted by the second high-reflection and high-transmission mirror 3 passes through the atomic gas chamber to the first high-reflection and high-transmission mirror 4, and after being reflected by the first high-reflection and high-transmission mirror 4, it passes through the cesium atomic gas chamber 5 again and then to the second high-reflection and high-transmission mirror 3, thus passing through the interior of the cesium atomic gas chamber 5 many times to form a resonant cavity resonance enhancement. Preferably, in this embodiment, in the cesium atomic gas chamber 5, the detection light induces the cesium atom to change from the ground state 6S 1 / 2 Transition to the first excited state 6P 3 / 2 , the pump light excites the cesium atom from the first excited state 6P 3 / 2 Transition to a Rydberg state with a principal quantum number greater than or equal to 50.

[0027] The interior of the cesium atom gas chamber 5 is filled with cesium metal atoms and a buffer gas. The buffer gas is an inert gas such as neon gas to suppress the collision between the cesium atoms and the wall of the cesium atom gas chamber.

[0028] Preferably, this embodiment also designs a 2-degree inclined wedge structure on the atomic gas chamber window to destroy the parallel reflection path between the window surfaces, thereby preventing the incident light from forming parasitic resonance inside the window, thereby eliminating light intensity fluctuations and ghost image interference, and ensuring the stability of the atomic excitation process and the purity of the detection signal.

[0029] The PZT piezoelectric ceramic 6 is rigidly connected to the first high-reflection and high-transmission mirror 4. By changing the voltage of the PZT piezoelectric ceramic 6, the position of the reflector is directly adjusted, thereby precisely changing the cavity length L and achieving cavity length frequency locking. Preferably, this embodiment also uses an adaptive control system to lock the resonant cavity length to the resonant state of the pump light wavelength of 509.53nm.

[0030] The light introduction component includes a first collimator 7, which is arranged on the outside of the first high-reflection and high-transmittance mirror 4. It is used to convert the detection light emitted by the optical fiber into parallel light and inject it into the resonant cavity. The collimated detection light can maintain a stable spot size over a long distance, thereby improving the detection accuracy.

[0031] Preferably, the light introduction and extraction assembly includes a second collimator 8 and a dichroic mirror 1. The second collimator 8 is disposed outside the second high-reflection and high-transmittance mirror 3, and the dichroic mirror 1 is disposed outside the second collimator 8. The second collimator 8 is used to convert the probe light emitted from the resonant cavity into parallel light and inject it into the dichroic mirror 1, and to convert the incident pump light into parallel light and inject it into the resonant cavity. The collimated probe light and pump light can maintain a stable spot size over long distances, thereby improving detection accuracy.

[0032] In this embodiment, due to the multi-layer dielectric film coated on the surface of the dichroic mirror 1, the dichroic mirror 1 has a high reflectivity for the pump light with a wavelength of 509.53 nm, typically >95%, and a high transmittance for the probe light with a wavelength of 852.35 nm, typically >95%. Therefore, when the probe light emitted through the second collimator 8 passes through the dichroic mirror 1, it can pass through the dichroic mirror 1 and be emitted to the photodetector.

[0033] Preferably, a photoelectric detection module is arranged outside the resonant cavity component, and the detection light emitted by the light introduction and extraction component is incident on the photoelectric detection module. The photoelectric detection module detects the electromagnetic induced transparent spectrum signal in the detection light and converts it into an electrical signal.

[0034] The control system implements a temperature-piezoelectric composite tuning mechanism. When the temperature changes slowly, the temperature control system responds first, maintaining temperature stability through heating / cooling to reduce cavity length drift. Mechanical disturbances in the resonant cavity cause instantaneous deviations in the cavity length, and the light intensity control module completes corrections with a microsecond response speed, ensuring that the resonant cavity is always in a resonant state with the 509nm detection light.

[0035] The control system includes a temperature control module and a light intensity control module. The temperature control module includes a temperature sensor, a temperature control unit, and temperature control components. The temperature sensor monitors and collects the temperature of the resonant cavity in real time. The temperature control unit generates a temperature error signal to drive the temperature control components. The temperature control components generally use a heater and a semiconductor cooler. When the temperature is above the target value, the cooler starts to cool down. When the temperature is below the target value, the heater starts to heat up, thereby controlling the temperature fluctuation within ±0.01°C.

[0036] The light intensity control module includes a power coupler, a light intensity control unit, and a PZT piezoelectric ceramic 6. The power coupler generally uses a beam splitter or photodiode to perform high-frequency sampling on a small portion of the detection light and pump light and convert it into an electrical signal. When the resonant cavity deviates from the resonance state due to factors such as temperature drift and mechanical vibration, the transmitted light intensity will change significantly. The power coupler can promptly detect the light intensity fluctuation. The light intensity control unit generally uses an FPGA (field programmable gate array) to receive the electrical signal from the power coupler, calculates the light intensity error signal through a PID algorithm, and drives the PZT piezoelectric ceramic 6 to directly adjust the relative distance between the first high-reflection and high-transmission mirror 4 and the second high-reflection and high-transmission mirror 3 of the resonant cavity, thereby changing the resonant cavity length and achieving cavity length locking.

[0037] The process of detecting partial discharge signals by the partial discharge probe according to the first embodiment of the present invention is as follows: S1. Set the parameters of the resonant cavity component, which include the free spectral range, finesse, mode field diameter, and atomic system parameters. The atomic system parameters include the cesium atomic chamber temperature, buffer gas pressure, and pump light detuning.

[0038] Preferably, in this embodiment, the free spectrum range FSR=1.5GHz, the finesse F=15000, and the mode field diameter is 1.2mm. The high finesse value of 15000 and the narrow free spectrum range of 1.5GHz jointly ensure that the resonant cavity outputs single-mode, narrow-linewidth laser. The mode field diameter of 1.2mm matches the atomic gas chamber, ensuring that the laser energy is efficiently coupled into the atomic system, enhancing the interaction strength between light and atoms, and improving the experimental signal-to-noise ratio.

[0039] Preferably, the cesium atom chamber temperature is 85°C, the buffer gas pressure is 5 Torr neon pressure, and the pump light detuning is -20 MHz. The high-temperature chamber provides sufficient atomic density to ensure that the pump light interacts with a large number of atoms. The 5 Torr neon gas reduces polarization relaxation caused by wall collisions while avoiding collisional decoherence caused by excessive pressure. The -20 MHz detuned pump light selectively excites slow-speed atoms, reducing the effects of Doppler broadening. Red detuning also reduces spontaneous emission losses and improves polarization efficiency.

[0040] S2. The frequency-locked detection light with a wavelength of 852.35 nm emitted by the optical path frequency stabilization module is incident on the first high-reflection and high-transmission mirror 4 after passing through the first collimator 7. The first high-reflection and high-transmission mirror 4 transmits the detection light to the cesium atomic gas chamber 5; the detection light passes through the cesium atomic gas chamber 5 and is emitted to the second high-reflection and high-transmission mirror 3. After being transmitted by the second high-reflection and high-transmission mirror 3 and collimated by the second collimator 8, the detection light is incident on the dichroic mirror 1. Then, after being transmitted through the dichroic mirror 1, the detection light is incident on the photodetector module. The photodetector module detects the EIT transmission spectrum signal in the initial detection light and converts it into a voltage signal.

[0041] S3. The optical path frequency stabilization module emits a frequency-locked pump light with a wavelength of 509.53 nm, which is reflected by the dichroic mirror 1 and incident on the second collimator 8; the second collimator 8 collimates the pump light and then emits the pump light to the second high-reflection and high-transmission mirror 3, and then the second high-reflection and high-transmission mirror 3 transmits the pump light into the resonant cavity component, and the pump light and the detection light are parallel to each other; the pump light passes through the cesium atomic gas chamber 5 and is incident on the first high-reflection and high-transmission mirror 4, and after being reflected by the first high-reflection and high-transmission mirror 4, it passes through the cesium atomic gas chamber 5 again and then reaches the second high-reflection and high-transmission mirror 3, and thus passes through the interior of the cesium atomic gas chamber 5 back and forth multiple times to form resonant cavity resonance enhancement.

[0042] At the same time, the temperature sensor in the control system monitors the resonant cavity and its internal temperature in real time, generates a voltage signal and outputs it to the temperature control unit; the temperature control unit compares the measured temperature with the target temperature, generates a temperature error signal, and drives the temperature control components to adjust the resonant cavity and its internal temperature in real time according to the temperature error signal issued by the controller module; and the power coupler in the control system converts the real-time sampled pump light intensity passing through the resonant cavity into a voltage signal and outputs it to the light intensity control unit; the light intensity control unit calculates the light intensity error signal through the PID algorithm and generates a light intensity drive signal; the PZT piezoelectric ceramic 6 generates a displacement, adjusts the distance between the first high-reflection and high-transmission mirror 4 and the second high-reflection and high-transmission mirror 3, and realizes cavity length frequency locking.

[0043] S4. When a partial discharge signal with a frequency range of 300 MHz to 2 GHz acts on the partial discharge probe described in an embodiment of the present invention, the energy levels of the cesium atoms in the cesium atom gas chamber 5 will shift under the action of the external electromagnetic field (AC-Stark effect), and the intensity of the detection light after passing through the cesium atom gas chamber 5 will change; the dichroic mirror 1 transmits the changed detection light to the photodetector, and the photodetector detects the EIT transmission spectrum signal of the detection light, thereby achieving the purpose of detecting the partial discharge signal. Example

[0044] As another embodiment of the present invention, Figure 2 As shown, the second embodiment of the present invention provides another partial discharge probe based on Rydberg atoms, including a protective shell, a resonant cavity component, a light introduction component and a light introduction and extraction component, a photoelectric detection module and a control system.

[0045] The resonant cavity assembly includes a cesium atomic gas chamber 5, a first high-reflection and high-transmission mirror 4, a second high-reflection and high-transmission mirror 3, a dichroic mirror 1, a third high-reflection and high-transmission mirror 9 and a fourth high-reflection and high-transmission mirror 10, which constitute the resonant cavity of this embodiment.

[0046] The first high-reflection and high-transmission mirror 4 responds to the detection light with high transmission and responds to the pump light with high reflection. The second high-reflection and high-transmission mirror 3 responds to the detection light with high transmission and responds to the pump light with high reflection and low transmission. The third high-reflection and high-transmission mirror 9 and the fourth high-reflection and high-transmission mirror 10 both respond to the pump light with high reflection. The wavelength of the detection light is preferably 852.35 nm, which is used to excite cesium atoms from the ground state 6S 1 / 2 Transition to the first excited state 6P 3 / 2 The wavelength of the pump light should be less than or equal to 509.53 nm. In this embodiment, the wavelength of the pump light is preferably 509.53 nm, which is used to excite cesium atoms from the first excited state 6P 3 / 2 Transition to a Rydberg state with a principal quantum number greater than 50.

[0047] The resonant cavity can allow a small portion of the pump light to pass through the second high-reflection and high-transmission mirror 3 into the resonant cavity, and reflect most of the pump light to maintain oscillation in the cavity. The reflectivity of the resonant cavity to the pump light is greater than 99.98%, and the transmittance is less than or equal to 0.02%; the transmittance of the resonant cavity to the detection light for a single pass is greater than 95%. The pump light transmitted by the second high-reflection and high-transmission mirror 3 is parallel to the detection light and is reflected into the cesium atomic gas chamber 5; the pump light emitted by the cesium atomic gas chamber 5 is reflected in turn by the first high-reflection and high-transmission mirror 4, the third high-reflection and high-transmission mirror 9, the fourth high-reflection and high-transmission mirror 10, and the second high-reflection and high-transmission mirror 3 into the cesium atomic gas chamber 5, thereby going back and forth between the four high-reflection and high-transmission mirrors many times and being parallel to the detection light many times in the cesium atomic gas chamber 5, forming a resonant cavity resonance enhancement. Preferably, in this embodiment, in the cesium atomic gas chamber 5, the detection light induces the cesium atoms to move from the ground state 6S 1 / 2 Transition to the first excited state 6P 3 / 2 , the pump light excites the cesium atom from the first excited state 6P 3 / 2 Transition to a Rydberg state with a principal quantum number greater than or equal to 50.

[0048] The interior of the cesium atom gas chamber 5 is filled with cesium metal atoms and a buffer gas. The buffer gas is an inert gas such as neon gas to suppress the collision between the cesium atoms and the wall of the cesium atom gas chamber.

[0049] Preferably, this embodiment also designs a 2-degree inclined wedge structure on the atomic gas chamber window to destroy the parallel reflection path between the window surfaces, thereby preventing the incident light from forming parasitic resonance inside the window, thereby eliminating light intensity fluctuations and ghost image interference, and ensuring the stability of the atomic excitation process and the purity of the detection signal.

[0050] Preferably, the dichroic mirror 1 is disposed outside the second high-reflection and high-transmission mirror 3. The detection light emitted from the cesium atomic gas chamber 5 is transmitted into the cesium atomic gas chamber 5 via the first high-reflection and high-transmission mirror 4, and then transmitted to the dichroic mirror 1 via the second high-reflection and high-transmission mirror 3. The pump light reflected by the dichroic mirror 1 is incident in parallel to the cesium atomic gas chamber 5 via the second high-reflection and high-transmission mirror 3. Due to the multi-layer dielectric film coated on the surface of the dichroic mirror 1, the dichroic mirror 1 has a high reflectivity (typically >95%) for the pump light with a wavelength of 509.53 nm, and a high transmittance (typically >95%) for the detection light with a wavelength of 852.35 nm. Therefore, the detection light emitted through the second collimator 8 can pass through the dichroic mirror 1 and be emitted to the photodetector.

[0051] The photoelectric detection module in this embodiment has the same performance as the photoelectric detection module in Example 1 and will not be described in detail here. In addition, the control system in this embodiment has basically the same performance as the control system in Example 1. The difference is that the PZT piezoelectric ceramic 6 in the light intensity control module is fixedly connected to the fourth high-reflection and high-transmission mirror 10. By changing the voltage of the PZT piezoelectric ceramic 6, the relative distance between the fourth high-reflection and high-transmission mirror 10 and the first high-reflection and high-transmission mirror 4, the second high-reflection and high-transmission mirror 3, and the third high-reflection and high-transmission mirror 9 is directly adjusted, thereby accurately changing the resonant cavity length L and achieving cavity length locking. Preferably, this embodiment also locks the resonant cavity length in the resonant state of the pump light wavelength of 509.53nm through the control system.

[0052] The process of detecting partial discharge signals using the partial discharge probe described in the second embodiment of the present invention includes four steps: S1, S2, S3, and S4. Steps S1, S2, and S4 are consistent with those in the first embodiment and are not described again here. Step S3 in this embodiment is as follows: S3. The optical path frequency stabilization module emits a frequency-locked pump light with a wavelength of 509.53 nm, which is reflected by the dichroic mirror 1 and then incident on the second high-reflection and high-transmission mirror 3. The pump light transmitted by the second high-reflection and high-transmission mirror 3 is parallel to the detection light and is incident on the cesium atomic gas chamber 5; the pump light emitted by the cesium atomic gas chamber 5 is reflected by the first high-reflection and high-transmission mirror 4, the third high-reflection and high-transmission mirror 9, the fourth high-reflection and high-transmission mirror 10, and the second high-reflection and high-transmission mirror 3 in sequence and is reflected into the cesium atomic gas chamber 5, thereby traveling back and forth between the four high-reflection and high-transmission mirrors many times and being parallel to the detection light many times in the cesium atomic gas chamber 5, forming a resonant cavity resonance enhancement.

[0053] At the same time, the temperature sensor in the control system monitors the resonant cavity and its internal temperature in real time, generates a voltage signal and outputs it to the temperature control unit; the temperature control unit compares the measured temperature with the target temperature, generates a temperature error signal, and drives the temperature control components to adjust the resonant cavity and its internal temperature in real time according to the temperature error signal issued by the controller module; and the power coupler in the control system converts the real-time sampled pump light intensity passing through the resonant cavity into a voltage signal and outputs it to the light intensity control unit; the light intensity control unit calculates the light intensity error signal through the PID algorithm and generates a light intensity drive signal; the PZT piezoelectric ceramic 6 generates a displacement to adjust the relative distance between the fourth high-reflection and high-transmission mirror 10 and the first high-reflection and high-transmission mirror 4, the second high-reflection and high-transmission mirror 3, and the third high-reflection and high-transmission mirror 9 to achieve cavity length frequency locking.

[0054] The partial discharge probes described in Examples 1 and 2 of the present invention, by combining resonance enhancement within the resonant cavity with a design where the detection light is separated from the cavity, can not only increase the light intensity enhancement factor of the 509nm pump light by 5-10 times, but also effectively improve the system sensitivity. Furthermore, the power requirement of the laser light source of the optical path frequency stabilization module can be reduced to 10mW, and the absorption rate can be effectively improved. These solve the problems existing in the prior art, such as the large system volume and high power consumption caused by the high-power laser light source, the disturbance of the atomic ensemble caused by the thermal effect induced by the strong laser, and the mode degradation phenomenon of the semiconductor laser when the power is greater than 50mW.

Claims

1. A partial discharge probe based on Rydberg atoms, characterized in that: Includes: A protective shell having a cavity structure; A resonant cavity component, wherein the resonant cavity component is built into the protective shell; A light introduction component, wherein the detection light incident component is arranged outside the resonant cavity component and is connected to the interior of the resonant cavity component through optical communication; A light introduction and extraction component is disposed on the other side of the resonant cavity component and is connected to the interior of the resonant cavity component via optical communication. The probe light emitted by the light introduction and extraction component passes through the interior of the resonant cavity component and is incident on the light introduction and extraction component. The pump light emitted by the light introduction and extraction component passes through the interior of the resonant cavity component and travels back and forth multiple times to the interior of the resonant cavity, thereby forming a resonance enhancement of the resonant cavity. The control system is used to sequentially control the temperature and light intensity in the resonant cavity within the target value range to maintain cavity length frequency locking.

2. A partial discharge probe based on Rydberg atoms according to claim 1, characterized in that: The resonant cavity assembly includes: A cesium atom gas chamber, wherein the cesium atom gas chamber is located in the middle of the internal cavity structure of the protective shell; a first high-reflection and high-transmission mirror, wherein the first high-reflection and high-transmission mirror is arranged between the cesium atom gas chamber and the light introduction component, and the detection light emitted by the light introduction component is incident on the cesium atom gas chamber; a second high-reflection and high-transmission mirror, which is arranged between the cesium atom gas chamber and the light introduction and extraction component and forms a resonant cavity with the first high-reflection and high-transmission mirror, and the pump light emitted from the light introduction and extraction component is incident on the cesium atom gas chamber after passing through the second high-reflection and high-transmission mirror; A dichroic mirror is arranged on the outside of the second high-reflection and high-transmission mirror. The detection light emitted by the cesium atomic gas chamber is transmitted into the cesium atomic gas chamber through the first high-reflection and high-transmission mirror, and then transmitted to the dichroic mirror through the second high-reflection and high-transmission mirror; the pump light reflected by the dichroic mirror is parallelly projected to the cesium atomic gas chamber through the second high-reflection and high-transmission mirror.

3. A partial discharge probe based on Rydberg atoms as claimed in claim 2, characterized in that: The second high-reflection and high-transmission mirror and the first high-reflection and high-transmission mirror are symmetrically arranged on both sides of the axial direction of the cesium atomic gas chamber. The pump light transmitted by the second high-reflection and high-transmission mirror is parallel to the detection light and irradiated into the cesium atomic gas chamber; the pump light emitted by the cesium atomic gas chamber is reflected by the first high-reflection and high-transmission mirror and then passes through the cesium atomic gas chamber again and then reaches the second high-reflection and high-transmission mirror, thereby passing through the interior of the cesium atomic gas chamber back and forth many times and irradiating the detection light parallel to each other many times in the cesium atomic gas chamber, forming a resonant cavity resonance enhancement.

4. A partial discharge probe based on Rydberg atoms as claimed in claim 2, characterized in that: The resonant cavity assembly further comprises: A third high-reflection and high-transmission mirror is arranged opposite to the first high-reflection and high-transmission mirror, and the pump light emitted from the cesium atomic gas chamber is incident on the first high-reflection and high-transmission mirror and is reflected by the first high-reflection and high-transmission mirror to the third high-reflection and high-transmission mirror; The fourth high-reflection and high-transmission mirror is arranged opposite to the third high-reflection and high-transmission mirror and the second high-reflection and high-transmission mirror. The pump light emitted by the first high-reflection and high-transmission mirror is reflected by the third high-reflection and high-transmission mirror to the fourth high-reflection and high-transmission mirror, and then reflected by the fourth high-reflection and high-transmission mirror to the second high-reflection and high-transmission mirror.

5. A partial discharge probe based on Rydberg atoms as claimed in claim 4, characterized in that: The pump light transmitted by the second high-reflection and high-transmission mirror is incident on the cesium atomic gas chamber in parallel with the detection light; the pump light emitted by the cesium atomic gas chamber is reflected by the first high-reflection and high-transmission mirror, the third high-reflection and high-transmission mirror, the fourth high-reflection and high-transmission mirror, and the second high-reflection and high-transmission mirror in sequence into the cesium atomic gas chamber, thus going back and forth between the four high-reflection and high-transmission mirrors many times and incident on the detection light in parallel many times in the cesium atomic gas chamber, forming a resonant cavity resonance enhancement.

6. A partial discharge probe based on Rydberg atoms according to claim 1 or 3, characterized in that: The light introduction components include: A first collimator is provided outside the first high-reflection and high-transmission mirror, and the detection light emitted by the first collimator is transmitted to the cesium atomic gas chamber through the first high-reflection and high-transmission mirror.

7. A partial discharge probe based on Rydberg atoms as claimed in claim 6, characterized in that: The light introduction and extraction components include: A second collimator is provided between the dichroic mirror and the second high-reflection and high-transmission mirror and is symmetrical to the first collimator.

8. A partial discharge probe based on Rydberg atoms according to claim 1, 4 or 7, characterized in that: Also included are: The photoelectric detection module is arranged outside the resonant cavity component. The detection light emitted by the light introduction and extraction component is incident on the photoelectric detection module. The photoelectric detection module detects the electromagnetic induced transparent spectrum signal in the detection light and converts it into an electrical signal.

9. The Rydberg atom-based partial discharge probe according to claim 1, wherein: The control system includes a temperature control module and a light intensity control module; The temperature control module includes: A temperature sensor is built into the resonant cavity and is used to monitor the resonant cavity and its internal temperature in real time, generate a voltage signal and output it to the temperature control unit; A temperature control unit is communicatively connected to the temperature sensor, configured to receive a voltage signal from the temperature sensor, compare the measured temperature with the target temperature, generate a temperature error signal, and drive the temperature control components to operate; A temperature control component, which is in communication with the temperature control unit and is used to adjust the temperature of the resonant cavity and its interior in real time according to the temperature error signal sent by the controller module; The light intensity control module includes: A power coupler, which is built into the resonant cavity and is used to convert the real-time sampled pump light intensity passing through the resonant cavity into a voltage signal and output it to the light intensity control unit; A light intensity control unit is communicatively connected to the power coupler, configured to receive an electrical signal from the power coupler, calculate a light intensity error signal using a PID algorithm, and generate a light intensity drive signal; PZT piezoelectric ceramic, the PZT piezoelectric ceramic is communicatively connected to the light intensity control unit, and is used to generate displacement according to the received driving signal, adjust the distance between the first high-reflection and high-transmission mirror and the second high-reflection and high-transmission mirror, and achieve cavity length frequency locking; or adjust the relative distance between the fourth high-reflection and high-transmission mirror and the first high-reflection and high-transmission mirror, the second high-reflection and high-transmission mirror, and the third high-reflection and high-transmission mirror.

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