30results about How to "Control output current" patented technology

The invention discloses an excitation state analysis-based low-voltage ride-through control method of a virtual synchronous power generator. The method comprises the steps of improving designs of droop characteristic, a reactive power ring and an active power ring by means of a reactive power adjustment principle of the synchronous power generator and a power grid which are connected in parallel,and the problems of excessive large reactive power increment, difficulty in preventing impact current and loop coupling reinforcement are effectively dealt with; and on the basis of no change on characteristic of the state analysis-based low-voltage ride-through control method of virtual synchronous power generator (VSG) system, an additional current ring is designed again, the under-excitation state running of an auxiliary system can be assisted during power grid fault period, an output current is adjusted, and a reactive power support is given out. A new directional method is employed, the transient process is accelerated, a control algorithm is not needed to be switched during the power grid fault period, a smooth switching strategy among states is also not needed to be added, and the low-voltage ride-through problem and the asymmetric drop of the power grid can be simultaneously dealt with.

The invention discloses a control gain adjustment method and device of a reactive power compensation device and a system. The method comprises a step of calculating a deviation value of control pointbus voltage according to a sampling value of the control point bus voltage and a target value of the control point bus voltage, a step of obtaining a control point operation short-circuit capacity ofan SVC, and a step of calculating an adjustment step number of the control gain of the SVC based on the deviation value of control point bus voltage and the control point operation short-circuit capacity. According to the method provided in the embodiment of the present invention, the adjustment step number of the control gain can be adjusted according to an actual value of the control point operation short-circuit capacity such that SVC controller gain parameters are matched with a short-circuit capacity of a power grid.

The invention discloses a mainboard cold standby power supply circuit which comprises a PSU and a BBU used for supplying power to a mainboard, a first switching circuit arranged on a power supply lineof the PSU, a second switching circuit arranged on a power supply line of the BBU, a current limiting switching circuit connected with the first switching circuit in parallel, and a control circuit.When the mains supply is just powered on or the PSU is just inserted into the circuit board, output is not stable, the PSU supplies power to the rear-end circuit through the current-limiting switch circuit. According to the mainboard cold standby power supply circuit, the output current of the PSU is limited, so that the situations of arc and the like caused by impact of large current generated when the output of the PSU is not stable on a rear-end circuit are avoided, namely, PSU hot plugging can be reliably realized without depending on a switching circuit working in an amplification region,and the safety and reliability of the mainboard cold standby power supply circuit are improved. The invention further discloses a storage server which has the same beneficial effects as the mainboardcold standby power supply circuit.

The invention discloses an integrated control circuit of an LED (light-emitting diode), comprising a central controller and multiple paths of LED driver circuits, wherein the central controller comprises a silicon controlled rectifier (SCR) and a dimming control trigger circuit; the dimming control trigger circuit comprises a manual luminance regulation trigger circuit and/ or an environmental luminance detection and luminance regulation trigger circuit and/ or a timing control and regulation trigger circuit and is used for outputting manual, light-operated and/ or time-control dimming signals; and each LED driver circuit comprises a main circuit, a signal detection, reshaping and conversion circuit and a current regulation and constant-control circuit. The dimming effect within a wider range can be obtained when the conduction angle of the SCR in a central controller changes within a small range; and in addition, the invention has simple circuit and low cost, does not generate large harmonic wave and can lower the possibility of harmonic wave pollution.

The invention discloses a high-reliability electronic meridian treatment instrument. The high-reliability electronic meridian treatment instrument comprises an operational amplifier power supply unit, a single chip microcomputer power supply unit, and a three-way treatment intensity adjustment output unit, wherein the three-way treatment intensity adjustment output unit comprises an A-way treatment intensity adjustment output unit, a B-way treatment intensity adjustment output unit and a C-way treatment intensity adjustment output unit; the operational amplifier power supply unit comprises a diode D1 and a diode D2; the single chip microcomputer power supply unit comprises a power supply voltage-stabilizing chip U5; the A-way treatment intensity adjustment output unit comprises an integrated circuit U7; the B-way treatment intensity adjustment output unit comprises an integrated circuit U8; and the C-way treatment intensity adjustment output unit comprises an integrated circuit U9. The high-reliability electronic meridian treatment instrument has the following advantages of high reliability, high anti-interference performance, capability of effectively controlling output current, stable voltage output, high signal output stability, low error, good curative effect and low manufacturing cost.

The invention relates to an electronic meridian treatment device with a small waveform distortion factor, comprising a total waveform generator U16, an integrated circuit U7, an integrated circuit U8 and an integrated circuit U9; a second pin of the total waveform generator U16 is connected with a third pin of a gliding resistor R22; a first pin of the integrated circuit U7 is connected with a fifth pin of a single chip U6; a first pin of the integrated circuit U8 is connected with an eighth pin of the single chip U6, a first pin of the integrated circuit U9 is connected with an eleventh pin of the single chip U6. The electronic meridian treatment device is good in anti-disturbance performance, stable in intensity output, high in reliability and low in fault rate; the waveform generating unit is stable in performance and low in cost, and featured by universality, usability, expansibility, and stability; the electronic meridian treatment device is strong in flexibility, powerful in function, small in output signal frequency bias, high in resolution rate and has full digital; the device is convenient to integrate and use; the work is stable; besides, the device is low in manufacturing cost, good in treatment effect, safe and reliable, and has good treatment effect.

The invention relates to a low-loss electronic meridian therapeutic instrument, which comprises a photoelectric coupler U13, a photoelectric coupler U14, a photoelectric coupler U15, an integrated circuit U7, an integrated circuit U8 and an integrated circuit U9. The pin 1 of the photoelectric coupler U13 is connected with the pin 2 of the photoelectric coupler U13 through a diode D22; the pin 1 of the photoelectric coupler U14 is connected with the pin 2 of the photoelectric coupler U14 through a diode D23; the pin 1 of the photoelectric coupler U15 is connected with the pin 2 of the photoelectric coupler U15 through a diode D24; the pin 1 of the integrated circuit U7 is connected with the pin 5 of a single-chip microcomputer U6; the pin 1 of the integrated circuit U8 is connected with the pin 8 of the single-chip microcomputer U6; and the pin 1 of the integrated circuit U9 is connected with the pin 11 of the single-chip microcomputer U6. The electronic meridian therapeutic instrument is good in anti-interference performance, is stable in intensity output, is high in reliability, is low in failure rate, is fast in reaction speed, is timely in feedback to a relay, can keep detecting cup drop in the whole therapeutic process, is low in manufacturing cost, is safe and reliable and has a good curative effect.

The invention relates to an anti-interference electronic meridian therapeutic instrument, which comprises an integrated circuit U7, an integrated circuit U8, an integrated circuit U9, a transformer U10, a transformer U11, a transformer U12, a triode Q2, a triode Q3 and a triode Q4. The pin 1 of the integrated circuit U7 is connected with the pin 5 of the integrated circuit U6; the pin 1 of the integrated circuit U8 is connected with the pin 8 of the integrated circuit U6; the pin 1 of the integrated circuit U9 is connected with the pin 11 of a single-chip microcomputer U6; the pin 1 of the transformer U10 is connected with the pin 4 of a power amplifier circuit U3; the pin 1 of the transformer U11 is connected with the pin 4 of a power amplifier circuit U2; the pin 1 of the transformer U12 is connected with the pin 4 of a power amplifier circuit U1; the emitting electrode of the triode Q2 is grounded; the emitting electrode of the triode Q3 is grounded; and the emitting electrode of the triode Q4 is grounded. The anti-interference electronic meridian therapeutic instrument is high in reliability, low in failure rate, fast in boosting speed and high in voltage stability; a set voltage can be reached in a short time, thereby improving precision of the electronic meridian therapeutic instrument; and the electronic meridian therapeutic instrument is not prone to damage and low in failure rate, being low in production cost and good in treatment effect, being safe and reliable, and has a better therapeutic effect.

The invention discloses a centrifugal fan intelligent cooling protection self-starting control system. The system comprises a centrifugal fan, a cooling structure, a temperature sensor, a controller, a display control panel, an alarm unit, a power supply and a cooling water tank, wherein the cooling structure and the temperature sensor are arranged on the centrifugal fan; the controller is connected with the centrifugal fan; the display control panel and the alarm unit are arranged on the controller; the power supply is connected with the controller; the cooling water tank is connected with the cooling structure through a cooling driving device; the temperature sensor is further connected with the controller; the cooling driving device is also connected with the power supply and the controller; the cooling driving device is a temperature control starting circuit provided with a cooling water pump; and the power input end of the temperature control starting circuit is connected with the power supply. The centrifugal fan intelligent cooling protection self-starting control system provided by the invention can automatically cool equipment at a high temperature during equipment operation and can give an alarm in time when the temperature exceeds a set value to remind related staff to maintain the equipment.

The invention relates to an electronic meridian therapeutic instrument with low fault rate. The electronic meridian therapeutic instrument comprises an integrated circuit U7, wherein the type of the integrated circuit U7 is X9C103S1. The first pin of the integrated circuit U7 is connected with the fifth pin of a single-chip microcomputer U6. The second pin of the integrated circuit U7 is connected with the sixth pin of the single-chip microcomputer U6. The electronic meridian therapeutic instrument has advantages of high interference resistance, stable output strength, high reliability, low fault rate, low manufacture cost, high treatment effect, high safety, high reliability and relatively high treatment effect.