74results about How to "No oscillation" patented technology

The invention belongs to the field of application of photovoltaic power generating system control technology, and relates to a maximum power tracking control method for a monopole three-phase photovoltaic grid-connected system. The method comprises the following steps of: firstly, by testing voltage and current outputted by a photovoltaic array, working out a differential coefficient k of the output power to the voltage of the photovoltaic array and a change rate delta k of the k; secondly, according to the k and an output Step1 of a fuzzy controller (an input is k and delta k, and the output is Step1), jointly determining the disturbance step length and direction of a disturbance voltage delta U which is superposed on a reference voltage U ref of a maximum power point of the photovoltaic array, and making the U ref quickly iterative and then converged at the optimal reference voltage corresponding to the maximum power point of the photovoltaic array under the current environment; and finally, realizing the quick and accurate tracking of the output voltage of the photovoltaic array on the U ref by a double closed loop control system consisting of a voltage PI controller and a synchronous vector current PI controller with feedforward compensation.

The present invention discloses a system and method for soft starting of an isolation direct-current converter applied to a direct current distribution network. After a direct-current converter is started, the H-bridge output square-wave voltage duty ratio of an input side is gradually increased from 0 to 0.5 according to a ramp function, and the time of setting the duty ratio from 0 to 0.5 is a starting time; after the direct-current converter is started, the H-bridge output square-wave voltage duty ratio of an output side is always 0.5, and the direct-current converter is started, in the starting time, output given voltage is gradually increased from 0 to a rated value according to the ramp function, and the changing of the output given voltage is consistent to the changing of the H-bridge output square-wave voltage duty ratio of the input side. Through cooperation control of the two methods, the current impact and direct voltage oscillation are effectively inhibited when starting, the system has a good anti-interference capacity and does not need additional circuits and starting resistors, and the starting logic is simple.

The invention relates to a magnetic source non-modulation type transmitter. The magnetic source non-modulation type transmitter is formed in a way that a man-machine interface, a GPS (Global Positioning System) module, a WIFI (Wireless Fidelity) module and a notebook computer are respectively connected with a master control module, the master control module is connected with a power supply through an A / D module and an H bridge circuit, the master control module is connected with a transmitting coil through a driving module, a clamping circuit and the H bridge circuit, the driving module is connected with the transmitting coil through a damping absorbing circuit and the H bridge circuit and connected with the H bridge circuit, and the clamping circuit is connected with the A / D module. The magnetic source non-modulation type transmitter solves ringing phenomena occurring when the current is lowered below zero and plays an important role of reducing primary filed influence in shallow detection. More pure secondary field signals are obtained, the quality of transient electromagnetic data is improved, and high-quality data are provided for the processing and inversion of transient electromagnetic data, in particular, transient electromagnetic early data. The magnetic source non-modulation type transmitter is suitable for various types of transmitting coils, the transmitting current waveform is controllable, turn-off time delay is short, the current falling edge linearity is high, the transmitting current is large, and the current leading edge raising speed is accelerated.

The present invention relates to a satellite formation relative orbit adaptive neural network configuration containment control method, and aims to solve the communication burden problems in the prior art brought by not considering the situations that a system exists the non-linear uncertainty and the external disturbance, not considering the situation that a satellite formation system kinetics exists the generalized interference, not considering a chattering phenomena and the known global information. The method of the present invention is realized by the following technical schemes of a step 1 of establishing a relative orbit kinetic equation of a following satellite i; a step 2 of designing a distributed speed observer for each following satellite in the step 1; a step 3 of carrying out the neural network approximation according to the relative orbit kinetic equation and the distributed speed observer of the following satellite i; a step 4 of designing an adaptive neural network configuration containment control algorithm according to a neural network approximation result obtained in the step 3. The satellite formation relative orbit adaptive neural network configuration containment control method of the present invention is applied to the satellite field.

The invention belongs to the field of dynamic positioning ship control and particularly relates to a ship positioning control method based on progressive guidance. The ship positioning control method comprises the following steps: (1) determining the target heading and the target position of a ship; (2) calculating real-time expected positions and the heading; (3) calculating required longitudinal force, lateral force, moment required during bow rotating, a north position deflection, an east position deflection and a bow direction deflection according to the current north position, the current east position, the current heading, a target north position, a target east position, a target heading, the longitudinal instantaneous speed of the ship, the lateral instantaneous speed of the ship, clockwise rotating rate, and longitudinal force, lateral force and moment which are generated by ambient disturbance. The positioning control method is designed based on progressive guidance and control. The moment and thrust which are obtained by the method gradually vary and can be ensured within the limit range of a propeller, so that the ship can stably arrive in the target position without oscillation, and the positioning precision is higher.

The invention relates to a control method for an autonomous underwater vehicle, in particular, a neural network S-plane control method for an autonomous underwater vehicle. According to an existing S-plane control method for an autonomous underwater vehicle, it is difficult to obtain optimal control parameters or difficult to adapt to complicated and varied marine environments, and as a result, amovement control effect is affected, while with the control method of the invention adopted, the above problem of the existing S-plane control method can be solved. According to the control method ofthe invention, as for an AUV control model, closed-loop control is performed on the AUV through an S-plane control method; an S-plane control link outputs control quantities in each control beat; andthe control parameters k1 and k2 of the S-plane control link of a controller are realized by a neural network-based prediction model and is determined through a multi-step prediction link, a feedbackcorrection link and a rolling optimization link. The control method of the invention is applicable to the control of autonomous underwater vehicles.

The invention discloses a method for realizing the priority processing of a specific message by utilizing a redirection technique. The method refers to a message processing system applied to a high-end exchanger of the Ethernet. When redirection rules are established, the method carries out data extraction to attribute fields, such as target MAC address, IP protocol type and port number in a specific protocol message, which are related to by an exchanger when data is processed, and writes the attribute fields into the menu item of an exchanging chip of a line card; the exchanging chip of the line card carries out automatic redirection to the protocol message according to the redirection rules; therefore, when the message is processed, the line card automatically transmits the specific protocol message to a main control board at high speed by an HG. After adopting the method, when the line card is impacted by messages of large flow, the exchanger still can ensure that: 1. the STP state of the port of the exchanger can be kept stably; 2. OSPF neighbors can be maintained, and route can be updated normally; 3. BGP neighbors can be maintained, and the route can updated normally.

The radio resource management server 1 receives radio link quality information measured by the radio base station 2 and radio link quality information measured by the radio base station 3 and thus detects the occurrence of interference. Upon the occurrence of the interference, the transmission power of the radio base station causing the occurrence of interference is controllably reduced to suppress the interference. In the method of controllably varying the transmission power of a radio base station, depending on the number of radio terminals or traffic volume, oscillation of a service area occurs. However, according to the present invention, the transmission power is changed on the occurrence of interference, without depending on the number of radio terminals or traffic volume, so that the area oscillation does not occur after the transmission power has been once stabilized.

The invention discloses a multi-model predictive control design method for a supercritical thermal power generating unit coordination control system based on a spatial metric algorithm, is used for controlling a supercritical coal-fired unit machine-furnace coordination system, and belongs to the field of thermal power engineering and automatic control. At present, machine-furnace coordination control systems of most power plants are designed based on conventional PID; during large-range variable-working-condition operation, performance of the coordinated control system is degraded due to thecharacteristics of large hysteresis, nonlinearity and time variation of a machine-furnace coordinated controlled object, so that the problems of low load regulation rate, poor precision, large main steam pressure and steam temperature fluctuation and the like of a unit in the operation process are caused. According to the invention, the traditional predictive control is properly simplified to realize the simplified design of linear predictive control; secondly, specific sub-model selection is realized in combination with a space measurement algorithm; and finally, a weighted soft switching strategy with simple calculation is provided for the integration of a plurality of sub-controllers, so that load regulation performance of a 660MW unit and operation stability of the unit can be remarkably improved, and the engineering requirements are met.

The invention relates to a computer control system for a novel direct drive lockstitch sewing machine. The computer control system comprises a master controller, a pedal speed regulator, an operation panel, solenoid valves, a power supply module, a motor, a motor drive controller and a photocoupling isolation module. The computer control system is characterized in that the master controller consists of a microprocessor CPU, a communication module, a driving module for the solenoid valves, a speed control module and a current control module; the microprocessor CPU realizes bi-directional data communication with the operation panel by a communication module circuit, realizes control and protection over actions of the solenoid valves of the sewing machine by a solenoid valve drive circuit, and realizes variable frequency control over the motor by the speed control module and the current control module; the master controller is respectively connected with the pedal speed regulator, the operation panel, the solenoid valves and the photocoupling isolation module; and the motor drive controller consists of a special servo drive module and a current detection module.

The invention discloses a control device for reducing escaped ammonia in a denitration process. The control device comprises an instant inlet ammonia spraying and distribution control device, wherein the instant inlet ammonia spraying and distribution control device is composed of a main pipe, a plurality of branch pipes, ammonia spraying electric valves, flue pipes, a plurality of ammonia spraying valves, and NH and NOX detectors, wherein one end of each branch pipe is communicated onto the main pipe; the ammonia spraying electric valves are arranged on the plurality of branch pipes respectively; the flue pipes are communicated with the other ends of the plurality of branch pipes; the ammonia spraying valves are arranged on side surfaces of the flue pipes and two opposite end faces of the flue pipes; the NH and NOX detectors are arranged on the plurality of ammonia spraying valves. The control device disclosed by the invention has the beneficial effects of simple structure and high practicability.

The invention discloses a non-linear PID adaptive control method based on a tracking differentiator. The method comprises the following steps of setting up the tracking differentiator TD; establishing a non-linear PID (NLPID) control law; and setting up an adaptive learning algorithm of an NLPID weight coefficient. The non-linear PID adaptive control method based on the tracking differentiator has great stability and convergence. Furthermore, the method which can accurately track reference signals achieves no overstrike and no oscillation and has strong robustness stability. Furthermore, the method has the characteristics of simple controller structure, clear theory model, no dependence on a controlled object model and low computational complexity. Therefore, the method is especially suitably used for real-time control on unknown objects or objects which are hard to model.

An oscillation echo canceller system (1), comprising a hollow body (5) having an insert part (4) with an opening (3) formed in a size matching the hole of an ear. A microphone (10) and a speaker (11) are installed in the hollow body. The speaker is so formed that a sound releasing hole faces the opening at the insert part, and two or more of the even number of sound releasing paths (12) of the same length and inner diameter are formed facing from the sound releasing hole to the opening. The microphone is installed in the opening at the insert part at a position apart from the sound releasing hole of the speaker, and a sound collecting path (15) collecting sound from the opening is formed of such a material that cannot directly collect sound from the sound releasing path of the speaker.

The invention discloses a rapid damping elasticity releaser for translation and a design method. The extent and the frequency of guide line translation are measured by an MEMS (micro electromechanicalsystem) inertia measurement system created by an MEMS accelerometer, the structure and damping parameters of a damping releaser are designed according to the extent and the frequency of the translation, wherein the damping parameters include elastic coefficients and lengths of pressure springs, the number of sections (namely the order of a damper), quality, texture, adjusting bolts and the like.The rapid damping elasticity releaser for the translation is designed and comprises a shell cylinder, sliding rods, bolts, seal rings, support bearings, the pressure springs or tension springs, balls,sleeves, the adjusting bolts and ejection balls. The working principle is that kinetic energy of a guide line is converted into elastic potential energy, non-vibration release is achieved, the elastic potential energy cannot return to the guide line, and guide line energy release curves are monotonous curves with large negative slopes. The damping elasticity releaser is simple in structure and convenient to replace, the kinetic energy of the guide line can be released rapidly, vibration is not generated, smoothness is high, and long service life and high application value are achieved.

The invention discloses an adaptive incremental conductance MPPT algorithm which is based on the incremental conductance algorithm and uses multiple step models combined with allowable errors to accurately control the converting circuit duty ratio D and to increase tracking efficiency and accurately respond to rapidly changing lighting conditions. The adaptive incremental conductance MPPT of the invention is characterized by quick tracking and accurate response under sudden changes in illumination with little fluctuation and without stable oscillation. Compared with the existing MPPT, the invention has better tracking performance, accurate response, no oscillation, high tracking efficiency, easy implementation, and reduced energy loss. The invention solves the problems that the existing algorithms often have oscillation, inaccurate response, low tracking efficiency and high difficulty in implementation. The improved step size model and precise directional control in the algorithm of the present invention are effective.

The invention relates to a vehicle-mounted sine wave inverter and an inversion control circuit thereof. The inversion control circuit comprises a voltage detection circuit, a current detection circuit, a voltage correction module, an SPWM (Sinusoidal Pulse Width Modulation) wave generation module and a driving circuit, wherein the voltage detection circuit and the current detection circuit are connected with a direct current input end of a DC / AC (Direct Current / Alternating Current) inversion circuit of the vehicle-mounted sine wave inverter and transmit detected direct current input voltage and direct current input current to the voltage correction module, respectively; the voltage correction module corrects the direct current input voltage according to the detected direct current input current and transmits a corrected value of the direct current input voltage to the SPWM wave generation module; and the SPWM wave generation module calculates and outputs an SPWM wave to the driving circuit to drive the DC / AC inversion circuit to convert direct current into stable alternating current. The inverter and the circuit employ direct voltage feedforward control and direct current compensation regulation to allow the output alternating voltage to be stable, complicated detection and calculation of the alternating voltage and proportional integral operation are not required, resources can be saved, and the inverter and the circuit output stably and operate reliably.

Provided is a rapid switching device for a 110kV power supply system of petrochemical enterprises. The rapid switching device comprises a microcomputer chip, and the microcomputer chip determines whether a reverse power starting condition, a zero-current starting condition, a voltage-loss starting condition, a tripping error starting condition and a protection starting condition are satisfied; if the tripping error condition is satisfied, a switching operation is started, and whether the other conditions are satisfied are further determined successively; if any condition except the tripping error condition is satisfied, an incoming switch tripping command is emitted, the switching operation is started, and whether a rapid switching condition, a same-period capture switching condition, a residual voltage switching condition and a long delay switching condition are satisfied is determined successively; if one of the condition is satisfied, determination is stopped, and a corresponding switching command, namely a rapid switching command or a same-period capture switching command or a residual voltage switching command or a long time delay switching command, is transmitted. Thus, the 110kV power supply system of petrochemical enterprises can be stably switched between a working power supply and a standby power supply.

The invention discloses a current / voltage conversion circuit with filtering and amplification functions and belongs to a current / voltage conversion circuit. The current / voltage conversion circuit comprises a current input end 1 and a voltage output end 2 and is characterized in that a current / voltage conversion signal circuit 3, a filtering circuit 4 and an amplification circuit 5 have a connecting relationship that: the current input end 1 is connected with resistors 6' in a current detection resistor sequence 6; a switch 7' in a multiway selection switch 7 is closed and the other switches 7' are open to form a voltage signal U1; noise is removed from the U1 by the filtering circuit 4 to form a voltage signal U2; and a voltage signal U3 with an increased amplitude, namely the voltage output end 2, is obtained after the U2 passes through the voltage amplification circuit 5. The current / voltage conversion circuit has the advantages that the current / voltage conversion circuit has a stable working state and is free from oscillation; the input dynamic range is wide; a weak current signal can be detected; the response time is short; the signal to noise ratio is high; and the current / voltage conversion circuit has an amplification function and a higher practical value, and facilitates subsequent processing.

The invention discloses a novel power grid reactive compensation device. The novel power grid reactive compensation device comprises a sensor unit, an acquisition and transmission controller, a dynamic power factor compensating controller, a power capacitor unit and a silicon-controlled switch unit, wherein the sensor unit and the dynamic power factor compensating controller are connected to the input end of the acquisition and transmission controller, the dynamic power factor compensating controller is connected to the output end of the acquisition and transmission controller, and the power capacitor unit and the silicon-controlled switch unit are connected to the output end of the dynamic power factor compensating controller. According to the novel power grid reactive compensation device, oscillation is avoided, the compensation effect is guaranteed, and the compensation precision is high.

A control device for zero-voltage conversion step-up power factor correcting circuit includes main source / drain voltage detection circuit, PWM comparator circuit and main assistant drive pulse distribution circuit; after detected by its detecting circuit, the VDSMAIN outputs ZVS, when VDSMAIN is low, ZVS is at low or high level, conversion of which is decided by logic circuit properties in main assistance drive pulse distribution circuit;PWM comparator circuit generates DRV signal with duty ratio of D2 and the pulse distribution circuit realizes making up assist drive signal VTzvt and main drive signal VTmain, so to satisfy sum of VGSZVT=DRV.ZVS and VGSMain=DRV.ZVS:VGSZVT+VGsmain=DRV.

Said method comprises: detecting the load utilizing state of current device and / or its neighboring devices; according to the detection result, knowing that if the current device and / or its neighboring devices are at overload state; if yes, keeping the logical topology state of device unchangeable.

The invention discloses an accelerator conveying and speed regulating control system. The system comprises an electrical machine, an oil pump, an electric proportional flow regulating valve, a motor and an accelerator pump which are connected in sequence, wherein the oil pump is connected with the electrical machine through a coupler I, the accelerator pump is connected with the motor through a coupler II, a speed measuring device is arranged on the coupler II, the electrical machine drives oil in the oil pump to flow into the motor through the electric proportional flow regulating valve, themotor is used for driving the accelerator pump, and the oil supply amount of the motor is changed by adjusting the electric proportional flow regulating valve so as to change the rotating speed of theaccelerator pump. According to the control system, data are collected through testing, curve fitting is carried out, the difference between the different accelerator pumps and adjusting flow proportional valves is considered, and the rapid and accurate speed regulation of an accelerator system is realized through data calibration during debugging. The method is simple, rapid, free of oscillation,rapid and stable, and high in precision.

The rotation amplitude and frequency of a wire are measured by an MEMS inertia measurement system, a structure and damping parameters of a releaser are further designed according to the rotation amplitude and frequency and the damping parameters mainly comprise an elastic coefficient of a torsional spring, the length of the torsional spring, the pitch number (the order number represents an n-orderdamper), the mass and the material, a rotary and rapid elastic releaser is further designed. The rotary and rapid elastic releaser comprises an outer shell cylinder, bolts, sealing rings, support bearings, torsional springs, a rolling bearing and a sleeve, wherein a working principle of the rotary and rapid elastic releaser is in a way that rotation energy of the wire is converted to elastic potential energy of the torsional spring, the elastic potential energy is released in a non-oscillation way, the torsional elastic potential energy cannot be returned back to the wire, and an energy release curve of the wire is a single curve with large negative slope. The rotary and rapid elastic releaser is simple in structure, the rotation motion energy of the wire can be particularly and rapidly released, oscillation cannot be generated, and the rotary and rapid elastic releaser is good in stability and has relatively long service lifetime and high application value.

The invention relates to a wide-voltage power supply control circuit which comprises an input protecting circuit, an input detecting circuit, a fuse fault indicating circuit, a control circuit, a driving circuit and an MOSFET fault indicating circuit. The input protecting circuit prevents reverse connection of two input power supplies. The input detecting circuit determines whether the two input power supplies satisfy a lowest input 10V requirement. The fuse fault indicating circuit performs fuse fault indicating on the two input power supplies. The control circuit controls the door electrode of the two-path MOS tube. The driving circuit drives the two input power supplies. The wide-voltage power supply control circuit can operate in the voltage 10V-100V. When the polarity of the power supply input end is in reverse connection, a power supply loop can be switched off automatically, thereby preventing damage of a load system caused by reverse voltage impact. The wide-voltage power supply control circuit has quick reverse current switching-off capability, and the switching-off time is not longer than 500ns, thereby effectively preventing backflow of load energy to the power supply input end or interference between the two input power supplies. Smooth switching between the two input power supplies can be realized, no oscillation occurs in the switching process.

The invention provides an analog PID control system and method based on the digital prediction algorithm. The analog PID control system based on the digital prediction algorithm at least comprises a prediction module and a PID controller. The prediction module is used for predicting an analog reference signal through the digital prediction algorithm to obtain a first analog control quantity of an execution mechanism. The PID controller is used for obtaining a second analog control quantity of the execution mechanism by calculation according to input deviation obtained by subtracting a feedback signal formed by an analog signal output by the execution mechanism from the analog reference signal, and then controlling the analog signal output by the execution mechanism by adding the second analog control quantity to the first analog control quantity output by the prediction module. According to the analog PID control system and method, by the adoption of the hybrid control strategy of the digital prediction algorithm and analog PID, the initial deviation of the analog reference signal and the feedback signal is small, output of the PID controller will not be saturate easily, the control precision is improved, and the cost is lowered.

The invention relates to a manipulator based on a torsion spring anti-loosening structure. The two sides of the lower end of a fixed plate are respectively hinged to a left manipulator finger and a right manipulator finger through swinging rods; the middle parts of the left manipulator finger and the right manipulator finger are hinged together; a torsion spring anti-loosening component is arranged at the hinged position of the left manipulator finger and the right manipulator finger; the two ends of a torsion spring in the torsion spring anti-loosening component are respectively fixed in the left manipulator finger and the right manipulator finger; the lower ends of the left manipulator finger and the right manipulator finger are respectively hinged to compression springs and force measurement sensor components. The anti-loosening structure of the manipulator based on the torsion spring anti-loosening structure takes the torsion spring arranged between the manipulator fingers as a main anti-loosening component, and meanwhile, a pair of compression springs is arranged at the finger tip positions to serve as auxiliary loosening elements. Because of the existence of clamping force in work, the energy consumption of a power source can be reduced effectively. The structure has small occupied space and work reliability, and does not influence the space of the manipulator for grabbing an object. The grabbing force of the manipulator for grabbing the object can be controlled conveniently by matching the force measurement sensors between the fingers.

The invention relates to an air-based translation and rapid damping releaser. The releaser comprises an air cylinder, a piston screw rod, a bolt, a sealing ring, a support bearing, a piston and a valve and is arranged on two wires or adjacent spacing rods. Due to moving of a wire in a reciprocating way, the piston is driven to move in a reciprocating way, air pressure can be constantly changed bykinetic energy of the wire, the piston at an air outlet of the valve can be pushed to different positions by wire motion in different amplitudes, holes are sequentially exposed from small to large, high-pressure air is further and constantly released, and thus, wire motion energy in different amplitudes can be rapidly released. The damping releaser is simple in structure and is convenient to replace, the wire motion energy can be particularly and rapidly released, no oscillation is generated, and the damping releaser has relatively long service lifetime and relatively high application value.

The invention discloses a comprehensive performance tester and test method for an in-swinging casement bottom hanging hardware system for a building window. The tester comprises a test frame for longitudinally fixing a test simulation window and is characterized in that an outer side face of the test frame is provided with a lateral opening driving mechanism and a bottom handing driving mechanism,an inner side face of the test frame is provided with a handle shifting mechanism for controlling the shifting of a handle, the lateral opening driving mechanism drives the test simulation window todo lateral opening repeated opening and closing movement in the test frame, and the bottom handing driving mechanism drives the test simulation window to do bottom handing repeated opening and closingmotion in the test frame. The test method comprises the steps that a horizontal cantilever beam drives a driven rod to make an arc motion, the driven rod drives the test simulation window to performlateral opening motion; a shifting servo motor drives a horizontal rotating shaft to rotate, and the horizontal rotating shaft drives the rotation of a handle knob; finally, the bottom hanging servo motor drives a screw rod to rotate, and a screw rod nut drives a screw rod drives the driven rod to perform a linear motion through a screw rod support seat. The failure rate is low, the precise control can be achieved, and the service life is long.

The invention discloses a rotary uncapping type vacuum blood collection tube which comprises a test tube body and a cap. A toothed groove is formed in the middle portion or the bottom of the outer wall of the test tube body, and an inwards-concave flat tube bottom is arranged at the bottom of the test tube body and used for sticking a sample label. The rotary uncapping type vacuum blood collection tube is matched with an automatic instrument, so that the cap of the rotary uncapping type vacuum blood collection tube with negative pressure can be automatically unscrewed by a mechanical arm, the phenomenon that the test tube body is broken or samples are vibrated due to the fact that the test tube body is clamped by large force when the vacuum blood collection tube is uncapped through manpower is avoided, the sample label is pasted to the bottom of the test tube body so that errors caused by vision shielding in the sampling process can be avoided, the structure is simple, operation is convenient, various defects caused by manual operation are overcome, manufacturing cost is low, adaptability is high, and great convenience is brought to achievement of automation of sample detection.

A valve section of a control valve controls the flow rate between a discharge chamber and a crankcase, based on the differential pressure between discharge pressure Pd and suction pressure. A pressure-sensing section is provided in a high-pressure port. When a pressure-sensing piston having a pressure-receiving area larger than a valve element is exposed to a rapid discharge pressure change, the differential pressure generated between the discharge pressure and a pressure in a pressure-adjusting chamber acts on the valve element opposite to the valve-opening / closing direction, to temporarily retard the motion of the valve element which opens or closes by the differential pressure. Even a high-sensitivity variable displacement compressor promptly restores without hunting to a predetermined discharge capacity.