4results about How to "Increased measurement bandwidth" patented technology

The application discloses a kind of absolute gravimeter device and method based on transparent medium microsphere free falling in optical standing wave.The application uses laser to build standing wave optical path along vertical direction, wherein standing wave one end beam is incident to light intensity detector.Then transparent medium microsphere is suspended in potential well, and microsphere is free falling in standing wave when potential well is closed.Light intensity detector receives periodic variation signal when microsphere repeatedly passes through wave node position, thereby real-time measurement microsphere displacement, and the acceleration value of falling is calculated, then potential well is opened to pull microsphere up to original release point and repeat falling.Compared with prism falling body in traditional gravimeter, microsphere falling body in the application is pulled back to release point in short time, and measurement bandwidth is high.There is no collision loss in deceleration process, and measurement life is long.Microsphere can be mass-produced, and volume is small and processing difficulty is relatively low.In short, the application provides a kind of absolute gravimeter method and device with high measurement bandwidth, miniaturization and low cost.

This invention relates to the field of in-situ impedance testing technology for energy storage batteries. To address the current difficulties in achieving rapid tracking of wideband excitation signals and the inaccurate identification and measurement of electrochemical parameters, it provides a battery in-situ impedance testing method and system based on adaptive phase compensation. The method includes acquiring the initial reference current and actual sampled current of the battery charging and testing system; iteratively calculating the real-time phase lag angle and generating a corrected reference current command accordingly; predicting the current response in two steps based on a discrete mathematical model of the full-bridge converter in continuous conduction mode; and optimizing the switching state corresponding to the voltage vector that minimizes the composite cost function to drive the switching transistors of the full-bridge converter. This method balances fast dynamic response with zero phase error tracking, meeting the high-precision requirements of in-situ EIS testing of energy storage batteries.

According to the vector magnetic field measurement method based on the self-excited cesium optical pump magnetometer, a regression equation set of each component of the magnetic field vector to be measured does not need to be constructed by a time sequence of multiple measurements, then the magnetic field vector is calculated, and the method has the technical characteristics of dynamic continuous measurement and large measurement bandwidth. A circular rotating modulation magnetic field is generated in an x-y plane through two paths of sinusoidal signals with the difference of pi / 2 provided by a signal source, two pairs of compensation coils can provide a uniform bias compensation magnetic field in the x-y plane, and a self-excited cesium optical pump magnetometer serves as a sensing unit and is placed in the geometric center of the device. A frequency meter outputs a digital signal of the total magnetic field size, the digital signal is converted into an analog signal through a DAC and then is input into lock amplifiers, two lock amplifiers LIAx and LIAy demodulate measurement signals of the optical pump magnetometer through two paths of modulation reference signals generated by a signal source respectively, after error signals are obtained, output of a current source x and output of a current source y are controlled through two PID, and the optical pump magnetometer is controlled through a current source. And the magnetic field components in x and y directions are measured through closed-loop locking.

The application provides a broadband light vector measurement method and device based on I / Q demodulation, which comprises the following steps: generating carrier-suppressed double-sideband linear frequency modulation light signals with fixed starting frequency difference as a measurement signal and a local oscillator signal respectively; passing the measurement signal through a light device to be measured to obtain a probe light signal; coherently mixing the probe light signal and the local oscillator signal through a 90-degree optical mixer, extracting I / Q two-way electrical signals through a balanced photodetector; constructing a complex signal to separate upper and lower sidebands and suppress mirror frequency interference, extracting fixed low-frequency components to obtain spectrum response information of the light device to be measured; obtaining the system's own spectrum response through a calibration process; eliminating the system response through complex division operation to obtain the amplitude response and phase response of the light device to be measured. The application can solve the spectrum aliasing problem in symmetrical double-sideband modulation without increasing the complexity of the system, expand the measurement bandwidth by one time, speed up the measurement, and does not need a wideband electrical amplitude and phase detector, effectively reducing the measurement cost.