152results about How to "Improve transient response performance" patented technology

The invention discloses a linear voltage regulator with a load detection circuit and a dynamic zero compensation circuit. The linear voltage regulator comprises an error amplifier, a voltage bumper, a power tube P-channel metal oxide semiconductor (PMOS), a first feedback resistance Rf1, a second feedback resistance Rf2, a load detection circuit and a dynamic zero compensation circuit, the load detection circuit is connected between an output end of the low-dropout linear voltage regulator and the voltage bumper, and the dynamic zero compensation circuit is connected between the output end of the low-dropout linear voltage regulator and the error amplifier. The load detection circuit is used for detecting the change of the load current, and then the load detection circuit controls the dynamic zero compensation circuit to produce dynamic zero zD to track and compensate a first non-dominant pole pEA of the linear voltage regulator. The dynamic compensation technology enables the low-dropout linear voltage regulator to have a better transient response performance and a smaller voltage spike for the load change compared with conventional structures. The load detection circuit and the dynamic zero compensation circuit have no static power consumption and no influence for the current efficiency of the whole low-dropout linear voltage regulator.

The invention belongs to the technical field of light source illuminating and electronics, in particular relates to an intelligent general light-emitting diode (LED) street lamp illuminating power supply system. The system comprises an input surge protection and electromagnetic interference suppressing circuit, a BOOST-BUCK isolation backlash power factor correction switch power circuit, an LED chip temperature detection circuit, an ambient brightness detection circuit, a permanent calendar chip, a peripheral circuit, an LED failure detection circuit, a singlechip circuit and a constant-current output control circuit. In the switch power circuit of the invention, a circuit structure is simplified and circuit efficiency is improved based on an active power factor correction (PFC) control chip L6562,; and the singlechip circuit monitors the ambient brightness, the temperature of the LED chip, time and LED fault in real time by taking a chip STC12C5606AD as a control core and intelligently adjusts the output brightness of the LED according to different situations, so that energy is saved and the service life of an LED street lamp is prolonged effectively at the same time.

The invention discloses an electrically-aided turbocharging system, and belongs to the technical field of turbocharging. The invention aims at providing an optimized electrically-aided turbocharging system adequately utilizing a turbine body structure, and a control method thereof. One end of the electrically-aided turbocharger disclosed by the invention is installed at an inlet end of an intake channel, and the other end of the electrically-aided turbocharger is installed at an outlet end of an exhaust channel; the electrically-aided turbocharger is composed of an aiding high-speed motor, a compressor, a turbocharger rotary shaft, a turbine and a waste gas bypass valve device; an intercooler is installed on the intake channel; an intake branch pipe is connected to a tail end of the intake channel; an exhaust branch pipe is connected to an inlet end of the exhaust channel; a gasoline engine cylinder is directly connected between the intake branch pipe and the exhaust branch pipe; the exhaust channel behind the exhaust branch pipe is divided into a first passage and a second passage which are connected in parallel; and tail ends of the first passage and the second passage both communicate with an outlet pipeline. According to the electrically-aided turbocharging system disclosed by the invention, the high-speed motor is combined with the turbocharger with the waste gas bypass valve, thus the influence of waste gas turbocharging for the performance of a gasoline engine is furthest utilized.

A boost system for an engine, comprising an engine having at least a cylinder; a fuel injector coupled to said cylinder; a compression device coupled to said engine; a compressed air storage device coupled to said compression device and configured to deliver compressed air to an air flow amplifier device located in the inlet air passageway to said cylinder; and a controller to adjust an amount of fuel injection to account for variation of air delivered to said cylinder from said flow amplifier device.

A switching power supply with a quick transient response is provided. A hysteretic control loop which comprises a hysteretic controller (117) and a control signal gate (116) is added to the original PWM control loop of the switching power supply. The hysteretic controller (117) is used to detect an output voltage (Vout) of the switching power supply and compare the output voltage (Vout) of the switching power supply with a reference voltage (Vref). When a load current (Iout) of the switching power supply is suddenly changed, the output voltage (Vout) of the switching power supply fluctuates. If the output voltage (Vout) of the switching power supply is in a setting range of the hysteretic voltage, output terminals (SELp, SELn) of the hysteretic controller (117) are in a low potential, and the control signal gate (116) selects output signals (Qp1, Qn1) from a PWM controller (101) as input signals of a gate signal drive circuit (106). If the fluctuation of the output voltage (Vout) of the switching power supply exceeds the setting range of the hysteretic voltage, an output terminal (SELp, SELn) of the hysteretic controller (117) outputs a high potential, and the control signal gate (116) selects output signals (Qp2, Qn2) of the hysteretic controller (117) as input signals of the gate signal drive circuit (106), so the operation of switching tubes (111, 112) at the power lever (102) of the switching power supply is controlled to stabilize the output voltage (Vout).

The invention relates to a novel current hysteresis control circuit. According to the novel current hysteresis control circuit, an error signal generating circuit is used for receiving an output voltage and a reference voltage of a power-level circuit and generating an error signal; a current detection circuit is used for detecting the current in the power-level circuit so as to generate a detection voltage signal for representing current information in the power-level circuit; a compensation signal generating circuit is used for generating a slope compensation signal, the rise slope factor of which is a first slope factor, in the rise time interval of the detection voltage signal; a control signal generating circuit is used for receiving the error signal, the detection voltage signal andthe slope compensation signal; and the detection current information is compensated by an added slope compensation signal so as to effectively stabilize the working frequencies under different input voltage conditions and realize the transient response compensation to an output load, therefore transient response is improved.

A boost system for an engine, comprising an engine having at least a cylinder; a fuel injector coupled to said cylinder; a compression device coupled to said engine; a compressed air storage device coupled to said compression device and configured to deliver compressed air to an air flow amplifier device located in the inlet air passageway to said cylinder; and a controller to adjust an amount of fuel injection to account for variation of air delivered to said cylinder from said flow amplifier device.

The invention relates to a control method of a light-type direct-current transmission system converter of an offshore wind power station, belonging to the technical field of power transmission. In the invention, a PID (Piping and Instruments Diagram) neural network controller is designed based on a particle group optimizing method, the traditional PI (Piping and Instruments) regulator is substituted, step input is used to train a neural network, that is to say, multi-group particles are set to search in the neural network weight space of searching, and the position and speed of the particles are continuously updated according to an adaptive value function of the neural network to obtain the optimum weight of the neural network. The invention adopts the method of using the optimum weight value obtained by training in combination with the error forward broadcast of the neural network to substitute the traditional PI regulator to control the operation of the system, thereby reducing the parameter to be regulated and improving the transient response performance of the system; the neural network weight value is obtained by training a nonlinear model of a controlled system so as to approach to a true system. Only the forward broadcast process of the PID neural network is controlled in the operation process of the system. The method is relatively simple and is easy to achieve.

The invention discloses a low dropout regulator. The low dropout regulator comprises an error amplifier composed of a first operational amplifier AMP1 and a second operational amplifier AMP2 in a cascading mode, a first operational amplifier regulating tube MK1, a second operational amplifier regulating tube MK2, an output regulating tube MP, a first feedback resistor RF1, a second feedback resistor RF2 and a miller compensation circuit composed of a capacitor CM and a variable resistor RM in a series connection mode. The miller compensation circuit composed of the CM and the RM replaces a buffer, and the problem that in the prior art, a large MP is needed in the condition that the same loads are driven, and consequently the area of a chip is increased is solved. Meanwhile, load currents are fed back to bias currents of the error amplifier through the MK1 and the MK2 to adjust the bias currents of the error amplifier, in the situation that an extra auxiliary circuit is not needed, the transient response performance can also be improved, and therefore under the premise that the LDO performance index is ensured, the purposes of lowering the design complexity and reducing the area of the circuit and the cost are achieved.

The application relates to a voltage conversion circuit and a control method. The voltage conversion circuit comprises an error amplifier which generates an error signal; a ratio amplification circuit which generates a gain signal according to output voltage and the error signal; a first comparator which generates a pulse signal according to the gain signal and a comparison signal; and a timer which generates a timing signal according to the pulse signal for indicating the turning-on / off time of the voltage conversion circuit. At least one of the gain signal and the comparison signal comprises a slope component, and the turning-on time of the voltage conversion circuit is constant. The technical scheme of the application can effectively improve the transient-state response performance of the voltage conversion circuit.

The invention discloses a stabilization control method of a VSC-HVDC power transmission system. The stabilization control method comprises a virtual resistance-inductance impedance stabilization control part, an output current feedforward control part, and a voltage current double-loop control part According to the virtual resistance-inductance impedance stabilization control, equivalent output impedance of a rectification station converter is corrected to be positive resistance, the damping of the system is enhanced, and the stability of the system is effectively improved, and the direct current side oscillation of the VSC-HVDC power transmission system is inhibited. According to the output current feedforward control, influences of receiving end load power abrupt changes on direct current busbar voltage are reduced, and the transient response performance of the system is improved. A direct current voltage outer ring adopts proportional plus integral control, and is used to track a direct current voltage instruction in an astatic way, and a grid-connected current inner ring adopts feedforward decoupling control under synchronous rotation coordinates, and then relatively low grid-connected current aberration is guaranteed. The stabilization control method is used for the control of the rectification station converter of the VSC-HVDC power transmission system, and the direct current side oscillation of the VSC-HVDC power transmission system is effectively inhibited, and the dynamic performance of the inversion station converter cannot be affected.

A secondary-ring control system for a single-inductor multiple-output switch power converter is disclosed. In the secondary-ring control system, a hysteresis comparator of upper-threshold voltage VH and lower-threshold voltage VL is employed in each secondary-ring control branch to replace a conventional secondary-ring error amplifier and a secondary-ring PWM comparator. The input of the hysteresis comparator in each secondary-ring control branch is n-1 differential-mode voltage V<fbi> (i=1, 2... n-1) respectively, and the V<fbi> is compared with the upper-threshold voltage VH and the lower-threshold voltage VL. When the V<fbi> is lower than the lower-threshold voltage VL, the duty ratio control signal PWM is of high level, and secondary power switch tube in corresponding output branch is turned on. When the V<fbi> is higher than the high-threshold voltage VH, the duty ratio control signal PWM is of low level, and secondary power switch tube in corresponding output branch is turned off. In this way, secondary duty ratio signals can be rapidly controlled through hysteresis comparators.

The invention relates to the field of electronic technology and particularly relates to a low-dropout linear voltage stabilizing circuit with low power consumption. The circuit consists of a core circuit, a frequency compensation circuit and a feedback circuit, wherein the core circuit consists of an operational amplifier AMP, a first P-type field effect transistor PM1, a first resistor R1 and a second resistor R2; the frequency compensation circuit consists of a fourth P-type field effect transistor PM4, a third resistor R3 and a first capacitor C1; and the feedback circuit consists of a second P-type field effect transistor PM2, a third P-type field effect transistor PM3, a first N-type field effect transistor NM1, a second N-type field effect transistor NM2 and a third N-type field effect transistor NM3. With a simple structure, the circuit provided by the invention realizes fast transient response and guarantees the circuit stability when the load current changes in a relatively large range.

The great-capacity single-phase brush-less synchronous generator has new-type superposed single-layer equal-turn single-phase sinusoidal winding; double-cage damping rotor system with less produced heat and excellent effect; specially designed exciting winding with powerful excitation capacity; and voltage regulator with sensitive load property identification, feedback and voltage regulating functions. The present invention makes it possible to develop great-capacity single-phase generator and to provide single-phase power supply with excellent electrical performance.

The invention discloses a frequency conversion control method and device for a single-inductor dual-output switch converter in a continuous conduction mode. By limiting inductive current peak and valley, the control on a main switch tube and branch switch tubes in the converter is finished and independent adjustment of each output branch is realized. Compared with a conventional single-inductor dual-output switch converter working in a continuous conduction mode, the frequency conversion control method and device have the advantages of good stability, high reliability, strong anti-jamming capability, high input or load transient response speed, little cross influence of the output branches and the like, and can be used for controlling various converters with single-inductor dual-output topological structures, such as a Buck converter, a Boost converter, a Buck-boost converter, a Bipolar converter and the like.

The invention relates to a high-speed train asynchronous traction motor square-wave single-loop flux weakening control method, which comprises the steps that 1, the maximum voltage U<smax> that an inverter can output is determined; 2, when an asynchronous attraction motor does not enter a square-wave operating condition, d-axis voltage u<sd> equals to u<sd1>, q-axis voltage u<sq> equals to u<sq1>, and when the asynchronous attraction motor enters the square-wave operating condition, the d-axis voltage u<sd> equals to u<sd1>, and the q-axis voltage u<sq> equals to the square root of (U<smax><2>-u<sd1><2>); 3, designing a flux weakening PI regulator according to a current relationship of the d-axis and the q-axis; 4, according to a switching control strategy, adopting a double-current-loop vector control strategy is adopted when the d-axis voltage u<sd1> is greater than the square root of (U<smax><2>-u<sd1><2>), and adopting a square-wave single-loop flux weakening control strategy when the d-axis voltage u<sd1> is less than the square root of (U<smax><2>-u<sd1><2>). The square-wave single-loop flux weakening control strategy is adopted, so that the tracking response capability of the current is improved, and thus the transient response capability of the current is improved; and smooth transition between double-current-loop vector control and square-wave single-loop flux weakening control is realized, and the asynchronous traction motor is ensured to have no current and voltage impact when the control strategy is switched.

The invention discloses a double-loop voltage type PFM (Pulse Frequency Modulation) control method for a single-inductor double-output switch transformer and a device for the double-loop voltage type PFM control method. A voltage type frequency conversion control technology is adopted for controlling a main switching tube by an external loop; a fixed-on or off time voltage type frequency conversion control technology is adopted for controlling output branch circuit switching tubes by an internal loop, thereby independently regulating each output branch circuit. The method and the device can be used for controlling various transformers of a single-inductor double-output topological structure, such as a Buck transformer, a Boost transformer, a Buck-boost transformer and a Bipolar transformer, and compared with a conventional voltage type PWM control method and device for the single-inductor double-output switch transformer, the method and the device have the advantages of low output voltage ripple, high steady-state performance, quick input transient response and load transient response, little cross influence among the output branch circuits of the transformer, and the like.

The invention provides a switching power converter system. The system consists of a switching power converter, a feedback circuit, an error amplifying circuit, a first RC network, a ripple generating circuit and a constant on-time control circuit. The error amplifying circuit forms an error amplifying signal according to a feedback signal and a reference signal and simultaneously forms a basis signal; the first RC network converts the error amplifying signal into an error integral signal. The ripple generating circuit generates a ripple signal, and superposes the ripple signal with the basis signal to generate a comparison signal. The error integral signal is compared with the comparison signal to generate a constant on-time control signal to control the switching power converter system, so that the switching power converter system is smaller in output ripples, and higher in transient response.

The invention belongs to the field of turbochargers for internal combustion engines, in particular to a rotor supporting mechanism of a rolling bearing turbocharger. It includes a bearing sleeve and two springs, two thrust sleeves and two bearings in the bearing sleeve. The two springs are symmetrically arranged in the bearing sleeve and connected to each other. Put the spring into the thrust sleeve and apply pre-tightening force. Two bearings are respectively arranged on the end face of the thrust sleeve. Both bearings are angular contact rolling bearings. The advantage of the present invention is that ceramic rolling bearings are used instead of ordinary floating bearings, which improves the mechanical efficiency and transient response capability of the turbocharger, solves the vibration problem of the rolling bearing turbocharger, and improves the steady-state performance and performance of the turbocharger. The service life of the rolling bearing is improved, the support rigidity of the rolling bearing is improved, the limit speed of the rolling bearing is increased, the requirement of high-speed operation of the turbocharger is met, the lubrication problem of the turbocharger is solved, the reliability of the rolling bearing supercharger is improved, and the balanced transmission The force system meets the requirements for the normal operation of the rolling bearing turbocharger.

An output over-voltage protection circuit for power factor correction, which includes a chip external compensation network, a chip external resistor divider network, a static over-voltage detection circuit, a dynamic over-voltage detection circuit and a compare circuit; The chip external compensation network is connected between the chip external resistor divider network and the dynamic over-voltage detection circuit, the chip external compensation network converts the dynamic over-voltage signal conversion to the dynamic current signal and conveys it to the dynamic over-voltage detection circuit, the dynamic over-voltage detection circuit detects the dynamic current signal and ultimately produces the dynamic over-voltage signal (DYOVP); The dynamic over-voltage signal (DYOVP) is inputted into the compare circuit, which converts the dynamic over-voltage signal (DYOVP) into a voltage compared with a reference voltage and outputs a over-voltage control signal (OVP), so as to achieve a dynamic over-voltage protection function.

The invention discloses an engine intake and exhaust control system and method. The engine intake and exhaust control system comprises an engine ECU, a gas circuit control valve and a double-effect pump. An exhaust gas bypass valve is arranged between an exhaust manifold and an exhaust pipe. The gas circuit control valve is connected with four gas circuits which are an EGR inlet pipe connected with the exhaust pipe, a bidirectional circulating pipe connected with an air inlet pipe, an intake branch pipe connected with an intake manifold and a pressurization gas pipe connected with the double-effect pump. The other end of the double-effect pump is connected with the intake branch pipe. On one hand, the double-effect pump serves as an EGR pump, enhances the capacity for introducing EGR exhaust gas and achieves stable adjustment of EGR within a whole working condition range; one the other hand, the double-effect pump serves as an electric air pressurizer, pressurizes air quickly and improves transient state response performance of an intake system. On-off conversion and control functions of the gas circuits are achieved through the gas circuit control valve, different requirements of an engine for recirculation exhaust gas or fresh air are met, and optimal power performance and exhaust performance are achieved.

The invention discloses a low dropout regulator (LDO) transient response enhancing circuit based on voltage induction. The LDO transient response enhancing circuit can obtain LDO transient state responding condition by detecting voltage on the output end of a load. When load current changes suddenly from low to high or from high to low, output voltage can drop or rise, when variation amplitude of the output voltage is larger than certain degree, a slew rate intensifier circuit is started, a grid of a compensating pipe can be charged or discharged fast to change the conduction degree of the compensating pipe, conduction current can be controlled to meet load requirements, and the effect of reducing output voltage overshoot can be achieved. According to simulation results, the LDO transient response enhancing circuit can remarkably improve load transient responding capability of an LDO.

The invention discloses a device for improving transient response of a natural gas engine and further discloses a response method of the device. The device comprises a gas inlet header pipe, a normalgas supplying channel, a fuel gas supplying pipe and a fuel gas spraying valve. The normal gas supplying channel further communicates with a transient response gas supplying channel. The device further comprises an accelerator position sensor used for detecting the opening degree of an accelerator pedal and a rotating speed sensor used for detecting the rotating speed of the engine. The normal gassupplying channel, the transient response gas supplying channel, the accelerator position sensor and the rotating speed sensor are connected to an electronic control unit (ECU) of the engine. Fuel gas is supplied to the engine through the normal gas supplying channel, when it is judged that the ECU needs to conduct transient response according to all detecting parameters, and the fuel gas is supplied through the transient response gas supplying channel; and meanwhile an anti-surging valve is opened to discharge air, air supplying is improved, the air inlet amount of the engine is increased quickly within a short time, and the transient response property of the engine is improved.

The invention discloses a turbo supercharged engine intake manifold of an integrated intercooler. The manifold is connected between an engine throttle valve and an engine cylinder cover and comprises the intercooler arranged in the turbo supercharged engine intake manifold. An air inlet of the turbo supercharged engine intake manifold is communicated with the intercooler through an isolation air channel. According to the turbo supercharged engine intake manifold of the integrated intercooler, a conventional air cooling intercooler is changed to be a water cooling intercooler, the intercooler is integrated in the manifold, an air outlet tube of the intercooler is eliminated, the length of an air inlet tube of the intercooler is shortened, the capacity of the air inlet tube of the intercooler is reduced, the length of the air inlet tube after supercharging is greatly shortened, the capacity of the air inlet tube after supercharging is greatly reduced, transient response performance of an engine is improved, and power performance of a vehicle is improved. Besides, the size of an air inlet system can be greatly reduced, the number of parts is reduced, the weight of the system is lowered, obvious cost advantages are achieved, arrangement of an engine compartment is optimized and the degree of freedom of the design of the whole vehicle is improved.

The invention discloses a low-pressure gas power generator set high-efficiency transient response device. The low-pressure gas power generator set high-efficiency transient response device comprises agas engine and a power generator. The gas engine is provided with an engine intake pipe. The engine intake pipe is connected with an air filter, a low-pressure gas mixer, a supercharger, an intercooler and an electronic throttle valve in series. A low-pressure gas supply device is further connected to the low-pressure gas mixer. A gas supercharging device communicates with a pipeline between theelectronic throttle valve and the engine intake pipe. A gas pressure relief device is connected to the low-pressure gas mixer and the supercharger in parallel. The low-pressure gas power generator sethigh-efficiency transient response device further comprises a parameter detection device and an engine controller ECU. The invention further discloses a specific control method of the low-pressure gas power generator set high-efficiency transient response device. When a power generator set is loaded suddenly, gas is concentrated and quickly fed into a cylinder block of the gas engine to realize quick loading and prevent the gas engine from flaming out. When the power generator set is unloaded suddenly, the supercharging pressure of the power generator set can be relieved quickly, and the supercharger can be protected against surge. The transient responsiveness and operation stability of the set are improved.

The invention discloses a battery charging circuit and a control circuit and a control method thereof. The battery charging circuit comprises a switching circuit which has at least one switching tube,the switching circuit provides system voltage for the load and charges a battery, and the control method comprises the steps that first difference value signals are produced on the basis of the difference values of charging current feedback signals and charging current reference signals; second difference value signals are produced on the basis of the difference values of the battery voltage feedback signals and the battery voltage reference signals; one of the first difference value signals, the second difference value signals and zero signals is selected as a difference value signal on thebasis of the battery voltage; the difference value signal is subjected to proportional integral to produce an offset signal; the control signals of the at least one switching tube in the switching circuit are adjusted according to the offset signal so as to adjust the output signals of the battery charging circuit to expected values.

The invention discloses a frequency conversion control method of an independent charging and discharging timing sequence single-inductance double-output switching converter and a frequency conversion control device. Control on a main switch tube and a branch switch tube of the converter is finished through limiting the amplitudes of a capacitive current peak and a capacitive current valley, and independent adjustment on various output branches is achieved. Compared with a traditional independent charging and discharging timing sequence single-inductance double-output switching converter, the independent charging and discharging timing sequence single-inductance double-output switching converter disclosed by the invention has the advantages of being good in stability, high in reliability, wide in load range, high in anti-jamming capability, high in input and load transient response speeds, small in cross influence among the output branches and the like, and can be used for controlling various converters, such as a Buck converter, a Boost converter, a Buck-boost converter, a Bipolar converter and the like, with a single-inductance double-output topological structure.

The invention relates to a control method for realizing a precontrol EGR system. According to collected variation rate signals of rotation speeds and loads of an engine, an adjustment amount of an opening degree of a precontrol EGR valve of next cycle is determined, and a pre-adjustment amount of the opening degree of the precontrol EGR valve is added based on an actual opening degree of the EGR valve, so a pre-opening degree of the EGR valve can be computed; and during the current signal sampling cycle, an ideal target opening degree of the EGR valve is determined by a controller according tothe rotation speeds, loads and various amendment signals of the engine; and then, the target opening degree is compared with the determined pre-control opening degree of the EGR valve, and a PID adjustment parameter is determined through MAP table checking based on an error between the two opening degrees and an error rate, whereas the EGR opening degree error is not adjusted through setting of the PID parameter based on multiple computations. The precontrol EGR system provided by the invention has the beneficial effects that a problem about slow transient responding of the system can be solved effectively; oscillation and excessive adjustment of the system are effectively reduced; and transient responding of the EGR system is improved.

The invention discloses a changeable air intake manifold of an engine and a control method of the changeable air intake manifold. The changeable air intake manifold is provided with a first air intake channel and a second air intake channel, wherein the second air intake channel is longer than the first air intake channel. The changeable air intake manifold is characterized in that an outlet of the first air intake channel and an outlet of the second air intake channel are arranged adjacent to each other and converge to an outlet of the changeable air intake manifold, valve plates are hinged to the adjacent pipe walls of the outlet end of the first air intake channel and the outlet end of the second air intake channel, a valve plate driving mechanism is arranged, and the valve plate driving mechanism drives the valve plates to rotate according to working conditions of the engine. The air intake flux can be controlled by controlling the positions of the valve plates. Through the changeable air intake manifold, the transient response performance of the engine is promoted, and the changeable air intake manifold is simple in structure and convenient to control.

Provided in the invention is a low-voltage-difference linear voltage regulator system comprising an error amplifier, a power tube, a conversion efficiency enhancement circuit, and a slew rate enhancement circuit. An inverted input terminal of the error amplifier is connected with a reference voltage VREF; and a non-inverted input terminal of the error amplifier is connected with an output voltageVOUT of an LDO. A grid terminal of the power tube is connected with the output terminal of the error amplifier; a source terminal of the power tube is connected with a power supply voltage VDD; and adrain terminal of the power tube is connected with an output voltage VOUT of the LDO. One end of the conversion efficiency enhancement circuit is connected with the non-inverted input terminal of theerror amplifier and the drain terminal of the power tube and the other end of the conversion efficiency enhancement circuit is grounded. The output terminal of the slew rate enhancement circuit is connected with the drain terminal of the power tube. According to the invention, in order to eliminate the restriction of the Capless LDO on a common chip, the system uses the slew rate enhancement circuit to improve the transient response of the LDO and employs the conversion efficiency enhancement circuit to realize high conversion efficiency, thereby prolonging the service life of the power supplydevice.