9 results about "Curvature compensation" patented technology

The invention relates to a curvature compensation control method for an alternating current electromagnet of a release, which comprises the following steps: S1, when a module is enabled, a processor detects the voltage Vs of a sampling circuit, and judges whether the voltage Vs is the initial value of a coil work cycle; s2, after the period starts, the microprocessor inquires the curvature compensation Dt value in the lookup table, S3, according to the Dt value, Dti is output as the PWM work period of the duty ratio, and i is the serial number of the numerical value in the array; and S4, outputting a signal to a power switch MOS, and driving a coil to be switched on or switched off until all Dt in the lookup table are output. According to the invention, curvature compensation is carried out on the duty ratio Dt of the PWM signal of the AC electromagnet coil, so that the current and power in the coil can be kept constant as far as possible, and the performance of the AC electromagnet is improved.

The invention relates to the technical field of analog integrated circuits, in particular to an index curvature compensation band-gap reference source circuit and system. Comprising a band-gap core sub-circuit, an index curvature compensation sub-circuit, a power interface and a voltage interface, wherein the band-gap core sub-circuit is used for generating positive temperature coefficient current; and the index curvature compensation sub-circuit is used for receiving the positive temperature coefficient current so as to generate a base current and further output an index curvature compensation voltage to the voltage interface. According to the band-gap reference source circuit with the exponential curvature compensation, the positive temperature coefficient current of the band-gap core sub-circuit is converted into the base current through the exponential curvature compensation sub-circuit, so that the influence of a first-order item temperature coefficient and a high-order item temperature coefficient in the positive temperature coefficient current is eliminated; the exponential curvature compensation voltage which is not influenced by temperature drift is output, and the precision and the stability of the output voltage are improved.

The low-temperature drift high-power noise suppression band gap reference circuit disclosed by the application comprises a starting circuit, a pre-stabilization circuit, a curvature compensation circuit, a core band gap reference circuit and a low-pass filter circuit, the starting circuit is used for power-on starting of the pre-stabilization circuit and the core band gap reference circuit, the pre-stabilization circuit is used for filtering a part of power ripples in advance and supplying power for the core band gap reference circuit, the curvature compensation circuit and the low-pass filter circuit, the curvature compensation circuit is used for injecting and extracting exponential currents respectively in the high-temperature section and the low-temperature section to complete temperature curvature compensation in different temperature sections, and the low-pass filter circuit is used for completing power ripple suppression in the high-frequency section. The low-temperature drift high-power noise suppression band gap reference circuit realizes high-order curvature compensation in a wide temperature range of high and low temperatures, so that the temperature drift is effectively reduced in the whole temperature range, thereby reducing the power consumption of the circuit and significantly improving the precision of the voltage reference. And the PSR of the circuit is greatly improved.

The invention discloses a curvature compensation band-gap reference circuit with a high power supply rejection ratio, which is characterized by comprising a pseudo power supply circuit, a starting circuit and a main body circuit, the pseudo power supply circuit is connected with the starting circuit, and the starting circuit is connected with the main body circuit; compared with a traditional band-gap reference circuit, the band-gap reference circuit has the advantages that the power supply rejection ratio of the band-gap reference voltage source is increased by using a pseudo power supply circuit technology, so that the reference voltage source can still keep stable when the power supply voltage changes; the influence of a linear component and a nonlinear component of a temperature coefficient in the circuit on the reference voltage is reduced through the main body circuit, so that the band-gap reference has a relatively low temperature drift coefficient in a wide temperature range, which is crucial for keeping the stability of the reference voltage; and on the premise of not increasing the scale of the circuit, the stability and reliability of the power supply can be effectively improved, and the overall performance of the power supply is improved.

The invention discloses a cross-connection NPN band-gap reference circuit with high power supply ripple suppression capability, which comprises a thermotropic current generation circuit, a reference voltage generation circuit and a curvature compensation circuit, and is characterized in that the thermotropic current generation circuit forms a voltage feedback network through a cross-connected NPN transistor pair to replace an operational amplifier clamping function; the current mirror structure is used for copying bias current to the NPN transistor pair to fix the voltage of each node, the reference voltage generation circuit is used for generating first-order reference voltage with a low temperature coefficient by combining the positive temperature current and the voltage characteristic of the NPN transistor, and the curvature compensation circuit is used for compensating the high-order temperature drift of the first-order reference voltage. According to the invention, an operational amplifier is replaced by the NPN transistor pair in cross connection, voltage negative feedback is formed through base-emitter interconnection, an operational amplifier module is omitted, the structure is simple, and the static power consumption is reduced; a node voltage self-stabilization mechanism formed by the cooperation of the current mirror and the fixed resistor eliminates the offset voltage influence of the operational amplifier.

This invention relates to a bandgap reference source curvature compensation system and control method, which discloses a temperature-adaptive scaling architecture: generating a voltage V complementary to the absolute temperature through a bandgap core circuit. CTAT and voltage V that is proportional to absolute temperature PTAT Two reference voltages; a dynamic scaling factor α(T) that varies linearly with temperature is constructed using a duty cycle resistor unit, such that α(T)·V PTAT This forms a secondary compensation term with no zero-point offset; the duty cycle is determined by the ramp voltage (from the reference voltage V). BG (Drive charging generation) and V PTAT A reference voltage is generated to ensure that the duty cycle D is proportional to the temperature T; and this is achieved through an independently adjustable resistor R. S and R R The primary and secondary temperature coefficients of the compensation term are adjusted separately, and the two have a chip-level linear correlation, supporting single-temperature point calibration. This solution achieves low-power, high-precision, and easily mass-producible curvature compensation.

The invention relates to an electrified test method and system for hydrophobicity of a composite insulator based on a power transmission line, and the method employs a high-resolution camera and precise water drop deposition to replace rough water spraying, and employs a contact angle algorithm based on curvature compensation to replace subjective comparison of human eyes, thereby improving the test precision, unifying the test standard, and improving the test efficiency. Meanwhile, the whole testing process is autonomously executed by a robot or remotely controlled by personnel on the ground, operation and maintenance personnel do not need to approach a high-voltage electrified body, huge safety risks of a traditional method are thoroughly avoided, full automation of the testing process is achieved, the operation and maintenance personnel do not need to carry heavy equipment to go to the site, and the testing efficiency is greatly improved; moreover, the automatically generated quantitative data can be directly stored in a database through networking, thereby facilitating the long-term and longitudinal trend analysis and state prediction of the hydrophobicity of the line insulator, and providing reliable data support for differentiated and intelligent operation and maintenance.

The present invention discloses a curvature compensation method and circuit that are immune to process variations. This method primarily addresses the problem that existing curvature compensation technologies are susceptible to process variations and are unable to achieve immunity to these variations. This method divides the reference voltage in a reference circuit using resistors. The divided voltage is applied to the bases of two identically sized bipolar junction transistors forming a differential pair structure. The difference in collector currents of the two bipolar junction transistors is used to generate a compensation current with a nonlinear component, thereby offsetting the nonlinear component in the reference voltage. This method can be used not only in bandgap reference circuits but also in Zener reference circuits. Its curvature compensation effect is unaffected by process variations, and the magnitude and direction of the curvature compensation can be easily adjusted by the user.

This invention discloses a curvature-compensated bandgap reference circuit with high power supply rejection ratio, characterized by comprising: a pseudo-power supply circuit, a startup circuit, and a main circuit; the pseudo-power supply circuit is connected to the startup circuit, and the startup circuit is connected to the main circuit; compared with traditional bandgap reference circuits, this invention improves the power supply rejection ratio of the bandgap reference voltage source by using pseudo-power supply circuit technology, enabling the reference voltage source to remain stable when the power supply voltage changes; and by reducing the influence of the linear and nonlinear components of the temperature coefficient on the reference voltage through the main circuit, the bandgap reference has a low temperature drift coefficient over a wide temperature range, which is crucial for maintaining the stability of the reference voltage; and without increasing the size of the circuit, it can effectively improve the stability and reliability of the power supply and enhance the overall performance of the power supply.