52results about How to "No throttling loss" patented technology

The invention discloses a digital electric-hydraulic synchronous control system, which comprises a hydraulic actuating mechanism, a digital synchronous control mechanism for performing synchronous control on the hydraulic actuating mechanism, an electric-hydraulic power source for providing power oil for the hydraulic actuating mechanism and the digital synchronous control mechanism, and an electric-hydraulic control system for controlling the power source and the synchronous control mechanism. The hydraulic actuating mechanism is a hydrocylinder; the electric-hydraulic power source comprises an oil storage tank, a double-acting hydraulic oil pump and a driving motor; the electric-hydraulic control system comprises a detector for detecting the oil pressure of the hydraulic oil pump and the rotating speed of the motor respectively and a variable frequency speed regulator and a controller for controlling the motor; and the digital synchronous control mechanism comprises a digital synchronization valve, a digital synchronization controller and a displacement transducer for detecting the displacement of an output shaft of the hydrocylinder. The digital electric-hydraulic synchronous control system has the advantages of simple structure, simple and convenient use and operation, good use effect, energy conservation and no oil leakage, and can achieve the aims of stepless speed regulation and high-precision synchronization according to operating characteristic requirements of different types of controlled objects.

The invention discloses a direct pump control type electro-hydraulic heaving compensation device. A servo motor drives a bi-directional hydraulic pump to rotate; two output ends of the bi-directional hydraulic pump are respectively connected with a rod cavity and a rodless cavity of a single-rod hydraulic cylinder; two overflow valves which are reversely mounted are also connected between the two output ends in parallel; an energy accumulator is connected with a quick connector on the rod cavity side of the single-rod hydraulic cylinder and is also connected with a first pressure sensor; two output ends of the bi-directional hydraulic pump are respectively connected with a second pressure sensor and a third pressure sensor; a rotating speed sensor is connected to the servo motor; all sensors and a servo motor driver are respectively connected with a control computer; a movable pulley is connected to a piston rod of the single-rod hydraulic cylinder; a fixed pulley is connected to the bottom of the single-rod hydraulic cylinder; and a built-in displacement sensor is mounted inside the single-rod hydraulic cylinder. The direct pump control type electro-hydraulic heaving compensation device has the advantages that an autonomous device is formed by a direct pump control differential cylinder closed type circuit; the servo motor, a hydraulic element and the sensors are integrated; closed loop control is carried out by the control computer; and throttling loss is avoided.

The present invention discloses a self-operated emergency cutting method of oil-gas pipe. According to the method of the invention, the emergency cutting-off to the pipe is realized through a triggering mechanism and a straight-through gate valve which is controlled by the triggering mechanism for opening and closing. The invention also discloses a self-operated emergency cutting valve for realizing the method. According to the invention, as the triggering mechanism is adopted for controlling the opening and the closing of the straight-through gate valve for realizing the emergency cutting-off so that the oil-gas inlet pipe is directly communicated with the oil-gas outlet pipe, so that the throttling and pressure loss are not generated. The cleaning to the pipe and the valve by the cleaning ball is facilitated and the impurity deposit is prevented. Furthermore the cut-off valve has the advantages of simple structure, reliable safety and low production cost. The method and the cut-off valve of the invention are not only suitable for conveying the natural gas, but also are suitable for conveying other liquid or gas medium of oil, steam, etc. The method and the cut-off valve of the invention can also be used for the initial product of oil-gas containing sand, water and sulfur, and can also be used for the oil production and gas production wellhead and the middle and downstream pipe network.

The embodiment of the invention discloses a hearth negative pressure control method. The hearth negative pressure control method comprises the steps of obtaining a measurement value furnace negative pressure; calculating deviation between the measurement value and a given expected value of furnace negative pressure; when the deviation is judged not to meet a preset allowable deviation range, adjusting the revolving speed of a motor of an induced draft fan till the motor of the induced draft fan operates at expected revolving speed, so as to realize the energy-saving reformation of the induced draft fan. Besides, the invention additionally discloses a hearth negative pressure control system.

Provided is an offshore crane heave compensation control system and method using video rangefinding to achieve heave compensation in a directly driven pump-controlled electro-hydraulic heave compensator. The heave compensation and the heave compensator are applicable for special operation and control requirements on a fixed offshore platform and allow the crane to achieve steady lifting of a load away from or lowering of a load on to a supply vessel without being influenced by the motion of the supply vessel caused by ocean currents, ocean winds, or ocean waves. Also provided is a test platform for the offshore crane heave compensation control system using video rangefinding. The test platform provides a realistic simulation for all lifting and lowering processes of an offshore platform crane in offshore environments to study the control of a motion control system on a fixed offshore platform.

The invention discloses a variable flow and household metering centralized heating system and a hydraulic balance regulating method. The system comprises household metering modules, a water supply temperature measuring module, a water returning temperature measuring module and a heat supply network monitoring and controlling management platform. The household metering modules are arranged at the positions of users, and the heat supply network monitoring and controlling management platform is in communication connection with the household metering modules and a total circulating pump and collects the water supply temperature and the water returning temperature in pipe network systems through the water supply temperature measuring module and the water returning temperature measuring module; and a frequency changer is arranged on the total circulating pump. The water quantity needs of the users are met, and on the premise that the heat comfort requirement of the users is met, the flow is adjusted according to needs, and energy consumption is reduced; and the cost is saved, the reliability and the stability are higher, and the system is more suitable for long-term utilization.

The invention relates to a swash plate piston hydraulic transformer controlled by a swing hydraulic motor, and relates to a hydraulic transformer controlled by a hydraulic motor. The problem that the automation and precise control of flow and pressure are unfavorably realized by a system in the traditional manually controlled hydraulic transformer is solved. A thrust plate (11) of the hydraulic transformer is arranged on a spindle (8) of the swing hydraulic motor. The invention is applied to the hydraulic transformer.

The invention discloses a control method for a supercritical unit participating in primary frequency regulation and a control system model. The method comprises the following steps: when the supercritical unit operates steadily under a given working condition, an intermediate pressure regulation valve is fully opened, and a high pressure regulation valve is regulated to a preset opening; when loadof the unit is increased, the opening of the high pressure regulation valve is increased, and the opening of the intermediate pressure regulation valve remains unchanged; when reduction of the load results in increasing of a power grid frequency, the opening of the high pressure regulation valve and the opening of the intermediate pressure regulation valve are reduced at the same time, and the high pressure regulation valve and the intermediate pressure regulation valve participate in primary frequency regulation at the same time; and after regulation, the intermediate pressure regulation valve is regulated to be in a full opening state. The high pressure regulation valve and the intermediate pressure regulation valve of a reheat turbine unit can participate in power grid primary frequency regulation at the same time, and the supercritical unit primary frequency regulation ability can be improved.

The invention provides an electro hydraulic actuator for a butterfly valve. The electro hydraulic actuator comprises a shell, an electronic control part and a hydraulic system. The electronic control part comprises a controller, a displayer, control switches and an angle sensor, wherein the displayer, the control switches and the angle sensor are connected with the controller. The hydraulic system comprises a bidirectional gear quantitive hydraulic pump, an AC servo motor, one-way valves, a pressure oil tank, a double-liquid-control one-way valve, a gear rack type hydraulic cylinder and the butterfly valve. The AC servo motor is connected with the controller, and an output shaft of the AC servo motor is connected with an input shaft of the quantitive hydraulic pump. The pressure oil tank is communicated with a low-pressure oil suction port of the quantitive hydraulic pump through the one-way valves. Two outlets of the quantitive hydraulic pump are communicated with the hydraulic cylinder through the double-liquid-control one-way valve. The angle sensor is fixed to the upper portion of the hydraulic cylinder. One end, extending out of the hydraulic cylinder, of a rotation shaft is connected with a rotation shaft of the angle sensor. An output shaft of the hydraulic cylinder is connected with a rotation shaft of the butterfly valve. A hydraulic cylinder drive is high in response speed, the integration of the hydraulic cylinder is high, and the electro hydraulic actuator has high market competitiveness.

The invention discloses a pneumatic water turbine. Water serving as a working medium of the pneumatic water turbine acquires energy through high-pressure gas. The pneumatic water turbine belongs to the technical field of energy and power. An energy converter of the pneumatic water turbine comprises two gas-liquid working cylinders, each of the gas-liquid working cylinder divides a sealing cylinder into a gas cavity and a water cavity through a piston, a connecting shaft penetrates through a sealing filler box, enters the water cavity and connects pistons of the two gas-liquid working cylinders, a solenoid valve is used for controlling energy of compressed air in a high-pressure gas tank to produce pressure water to push the water turbine, and part of the energy of the compressed air is used for pushing a gas turbine. High-pressure air expands slowly in the gas cavity, external heat is absorbed fully, an air working medium approaches isothermal expansion, the energy utilization rate of the high compression air is improved greatly, by the aid of high-efficiency energy conversion of the water turbine and most of available energy which is converted by the gas turbine from exhaust, and the whole system is free from throttling loss of the high-pressure air, gas leakage loss and tail gas loss, so that the efficiency of the whole water turbine is higher than that of an existing pneumatic motor.

The invention relates to an electro hydraulic pressure well repair operating machine which is composed of a bottom vehicle, a winch, a head frame and roving system, an operating room, a motor, a hydraulic pressure variable displacement pump, a hydraulic pressure motor a speed change box, a multi-way reserving valve, a motor transferring case, a hydraulic pressure oil tank, a controlling valve block, a hydraulic pressure jigger winch, a cable winding drum, an electrical cabinet, a braking system, an electrical controlling system and an auxiliary system, the operation and the control of the electro hydraulic pressure well repair operating machine provided by the invention is convenient, a pump controlling system, the throttle is not lost, the energy consumption is low, the utilization ratio and working efficiency of the energy are high, the effect of the energy conservation is obvious, the standby power can be utilized to work on the condition of being short of the power sources on the site, and the normal oil-water well repair operation is ensured.

The invention belongs to the application field of heating units, and in particular discloses a device for improving the heating economy of a pure condensation reforming heating unit. The device for improving heating economy of the pure condensing reformed heating unit includes a heat network heater, which is characterized in that: a regulating valve is provided on the heat supply and exhaust pipe connected to the heat network heater, and a cold water inlet is provided on the heat network heater. Pipe and hot water outlet pipe, a thermostat is installed on the hot water outlet pipe, the control valve is connected to the cold water inlet pipe and the hot water outlet pipe, and the thermostat is connected to the control valve. The invention has the advantages of simple structure, convenient use, reasonable design, flexible application, no throttling loss, automatic temperature control, automatic adjustment of heat load, and no influence on electric load adjustment within the design range, and is suitable for wide popularization and application.

The invention relates to a pumped storage thermodynamic system of a thermal power plant. Specifically, the pumped storage thermodynamic system comprises a water feeding heater, a deoxidizing heater, a condensed water heater and a hot water storage device. The hot water storage device is arranged in the thermodynamic system, so that a part of drained water flowing out of a water system is stored in the hot water storage device, under the working condition that unit load needs adjusting, the drained water is supplemented to the thermodynamic system, and the effect of increasing the unit load or adjusting the frequency can be achieved. Throttling loss is avoided, impact on an original thermodynamic system is small, and the advantages in the aspects of operation economy and safety are remarkable.

The invention relates to an auxiliary power system with a direct-current (DC) frequency converter and a DC variable-frequency motor. Specifically, the system comprises an off-site alternating-current (AC) power grid, an on-site AC power grid, an on-site DC power grid, an AC generator or AC generator unit, an AC transformer, an AC / DC converter or transformer, a DC frequency converter, and a DC variable-frequency motor. By adopting the system, variable-speed running of power plant equipment can be effectively realized, the energy loss of the generator unit can be significantly reduced, the overall efficiency of the unit can be improved, and the unit can be simplified. Moreover, the system has the characteristic of controllable cost.

The invention relates to the technical field of robots, in particular to a joint driving device of a wheel-legged robot, a control method and the wheel-legged robot, the joint driving device comprises a hip joint rotating actuator, a knee joint rotating actuator and a motor, the hip joint rotating actuator performs displacement closed-loop control extension / contraction through a hip joint electro-hydrostatic actuator, and the knee joint rotating actuator performs displacement closed-loop control extension / contraction through a knee joint electro-hydrostatic actuator. The knee joint rotation actuator performs displacement closed-loop control extension / contraction through the knee joint electro-hydrostatic actuator, the knee joint rotation actuator performs force closed-loop control vibration reduction through the knee joint electro-hydrostatic actuator, and the motor drives the wheels to rotate / stop through the controller. The wheel-legged robot aims to take wheel-type modal operation as a main mode and simple step-type modal movement as an auxiliary mode, and can well realize a vibration reduction function in a wheel-type mode and can well realize a leg stretching function in a step-type mode, so that the flexibility and functionality of the wheel-legged robot in an actual use process are considered.

The invention discloses a priority flow control system based on a compression vehicle feeding device, and belongs to the technical field of transmission systems of sanitation vehicles. The system comprises a double pump, wherein a large pump of the double pump is connected to large pump oil supply way, a small pump of the double pump is connected to a feeding device oil cylinder, the small pump isconnected to a priority valve, an oil outlet of the priority valve is separately connected to a one-way valve and a proportional valve, the one-way valve is connected to the large pump oil supply way, and the proportional valve is connected to the feeding device oil cylinder. According to the system, flow of the small pump is preferentially supplied to the feeding device, redundant flow is supplied to a large pump oil supply loop through a bypass, the use efficiency of the double pump is exerted to the maximum extent, and the working efficiency of the large pump oil supply loop is improved, the same hydraulic system can guarantee speed stability of different feeding device during acting, has no throttling loss, improves the system power utilization rate, simultaneously improves a system uniformity degree, and reduces system configuration.

The invention belongs to the technical field of hydraulic energy saving, and relates to an electro-hydraulic direct-drive servo closed differential control driving system for a stepping lifting mechanism. The system involves a double-rotation-direction hydraulic pump, a differential hydraulic cylinder, a double-rotation-direction servo motor and an energy accumulator set, wherein the double-rotation-direction hydraulic pump is provided with two pressure oil opening ends, and the which double-rotation-direction hydraulic pump is connected with the energy accumulator set and the differential hydraulic cylinder correspondingly; and the double-rotation-direction servo motor is used for controlling the output flow and direction of the double-rotation-direction hydraulic pump. According to the electro-hydraulic direct-drive servo closed differential control driving system for the stepping lifting mechanism, an electro-hydraulic direct-drive servo technology is combined with the energy accumulator set and an electric energy storage device to control the lifting motion of the differential hydraulic cylinder, and a differential hydraulic cylinder control method is adopted, so that the transmission control principle is simplified, the service life of the hydraulic cylinder is prolonged, the motion characteristic of the driving system is improved, and valve control throttling loss is avoided; and meanwhile, gravitational potential energy and servo motor braking energy are recycled, and compared with a traditional energy-saving technology, the energy-saving efficiency is higher, the system is simpler, the reliability is higher, the investment is more saved, and the operation and maintenance cost is lower.

The invention relates to a multipath valve of a double valve element crane capable of controlling a micro flow precisely and belongs to the mechanical field. The multipath valve comprises a large drift diameter valve element, wherein a pilot control port Pa, a left side displacement sensor of the large drift diameter valve element, a port Pb and a right side displacement sensor of the large driftdiameter valve element are connected to the left end of the large drift diameter valve element; a port Pb and a right side displacement sensor of the large drift diameter valve element are connected to the right end of the large drift diameter valve element; a small drift diameter valve element is connected in parallel on a working oil path and an oil return path of the large drift diameter valveelement, and oil inlet paths of the large and small valve elements are independent. The small drift diameter valve element is started in a final motion, so that the resolution of the system and the positioning precision of an executing element are improved. The large valve element is started in a high speed large flow, so that a low pressure loss in the high speed large flow can be achieved quickly. The multipath valve is low in energy consumption.

The invention discloses an excavator negative flow system sensitive to load. The system comprises a hydraulic proportional direction valve, a servo piston, an engine, a variable pump, a metering pump, a first overflow valve, opened-center six way proportional directional valves, cylinders, a plurality of shuttle valves, a solenoid directional valve, a constant difference overflow valve, a throttle, a second overflow valve and the like. The constant difference overflow valve and the shuttle valves are arranged in front of the throttle, the shuttle valves are utilized to obtain the maximum pressure of load and guide to the constant difference overflow valve to control a hydraulic fluid port, and the displacement of the variable pump is maximized before the pressure required to overcome the load is provided at the variable pump outlet, meanwhile, the hydraulic oil return port of the variable pump is sealed, and the pressure required to overcome the load is allowed to be provided at the variable pump outlet rapidly. By the aid of the excavator negative flow system, energy loss of a hydraulic pump can be reduced when a main control valve is in the neutral position, the throttle has no throttling consumption before the pressure required to overcome the load is provided, and energy loss of a hydraulic system is reduced.

The invention relates to a forklift hydraulic system with energy recovery and double-pump oil supply functions. The forklift hydraulic system comprises an oil tank, a first oil pump, a motor, a multiway valve, two lifting oil cylinders, two inclined oil cylinders, a steering oil cylinder, a load sensing steering gear, a second oil pump, a directional control valve and a speed limit valve, wherein the multiway valve consists of an oil inlet and return valve plate assembly, an inclined reversing valve plate and an oil inlet valve plate, and is a plate type multiway valve; a three-position eight-way lifting reversing valve and a first main safety valve are arranged in the oil inlet and return valve plate assembly; the inclined reversing valve plate comprises an inclined three-position six-way reversing valve, a first oil adding overload valve and a second oil adding overload valve; the oil inlet valve plate comprises a split-flow valve, a priority valve, a steering safety valve and a second main safety valve. The forklift hydraulic system is suitable for not only hybrid power forklifts but also electric forklifts. For example, after a 7t electric forklift is charged once, according to the test results of an energy consumption test method of the whole vehicle, the energy consumption of the system is reduced by 25%, and the working cycle time of the whole vehicle is prolonged by 50 minutes.

The invention discloses a wheeled leg robot and a driving method thereof, and belongs to the technical field of wheeled leg robots, the wheeled leg robot comprises a vehicle body, thighs, shanks, wheels and two hydraulic control systems; one end of the thigh is hinged with the vehicle body, and the other end is hinged with one end of the shank; wheels are arranged at the other ends of the shanks;the two hydraulic control systems control the included angle between the vehicle body and the thigh and the included angle between the thigh and the shank respectively. The hydraulic control system comprises a hydraulic cylinder and a piston rod; a bearing cavity, a non-bearing cavity and a spring are arranged in the hydraulic cylinder; the piston rod divides the bearing cavity and the non-bearingcavity; and the spring is used for enabling the rod part of the piston rod to tend to extend out of the hydraulic cylinder. According to the wheeled leg robot and the driving method thereof, overflowloss and throttling loss are avoided, the system power is saved, the transmission efficiency of a hydraulic system is high, the energy utilization rate is high, the buffering performance is good, andthe service life is long.

The invention discloses a wheeled leg robot and a driving method thereof, and belongs to the technical field of wheeled leg robots, the wheeled leg robot comprises a vehicle body, thighs, shanks, wheels and two hydraulic control systems; the hydraulic control system comprises a hydraulic cylinder, a piston rod and a motor gear control system; a bearing cavity and a non-bearing cavity are formed inthe hydraulic cylinder; the piston rod separates the bearing cavity from the non-bearing cavity; a hydraulic control system controls the extension of the piston rod relative to the hydraulic cylinderor controls the included angle between the vehicle body and the thigh through a motor gear control system; and the other hydraulic control system controls the extension of the piston rod relative tothe hydraulic cylinder or controls the included angle between the thigh and the shank through a motor gear control system. According to the wheeled leg robot and the driving method thereof, overflow loss and throttling loss are avoided, the system power is saved, the transmission efficiency of a hydraulic system is high, the energy utilization rate is high, the buffering performance is good, and the service life is long.

The invention discloses a household hydraulic stereo garage which comprises a parking board, a main frame, a lifting block, a vertical column, a rotating platform, a control box, traveling wheels, a guide rail, a hydraulic control loop, a high-pressure pipeline, a rotary motor, a first displacement sensor, a traveling motor, a second displacement sensor, a hydraulic mechanical cylinder, a controller and a low-pressure pipeline. The household hydraulic stereo garage adopts a novel element, namely the hydraulic mechanical cylinder, achieves the functions of energy recovery and dual locking, andmeanwhile has the advantages that a hydraulic control valve is not needed, the energy efficiency is high, and the structure is compact.

The embodiment of the invention discloses a hearth negative pressure control method. The hearth negative pressure control method comprises the steps of obtaining a measurement value furnace negative pressure; calculating deviation between the measurement value and a given expected value of furnace negative pressure; when the deviation is judged not to meet a preset allowable deviation range, adjusting the revolving speed of a motor of an induced draft fan till the motor of the induced draft fan operates at expected revolving speed, so as to realize the energy-saving reformation of the induced draft fan. Besides, the invention additionally discloses a hearth negative pressure control system.

A rotor type Stirling refrigerator and its working method belong to the field of refrigeration equipment. It includes a special-shaped triangular rotor and a rotor housing cavity. There is a hole at the bottom that allows the special-shaped triangular rotor to communicate with the outside world. The special-shaped triangular rotor is provided with a tubular extension on which an external gear is installed. An eccentric shaft is inserted into the tubular extension. The eccentric shaft Driven by the motor through the coupling, the external gear matches the fixed inner gear at the bottom of the rotor housing cavity to ensure that the motor drives the special-shaped triangular rotor through the eccentric shaft to move in the rotor housing cavity. Four through holes are opened on the top, and two U-shaped heat exchange tube groups are respectively arranged on the four through holes. The rotor-type Stirling refrigerator avoids the vibration problem of the traditional rhombic transmission and the crank-connecting rod Stirling refrigerator, and the efficiency is improved by relying on the rotor drive, and the structure is more compact. The internal working medium is in a sealed state, isolated from the outside world, and there is no phase change and throttling process during circulation.

The invention relates to a steam extraction back pressure type feed pump turbine back pressure adjusting system and method. The system comprises a feed pump small turbine, a driving steam pipeline, aregenerative steam extraction pipeline, a regenerative steam extraction pipeline adjusting valve, a converging header, a steam extraction and supplementing pipeline adjusting valve, a discharging pipeline adjusting valve and a back pressure controller. The driving steam pipeline is connected with a small steam turbine; middle extraction steam of the small steam turbine enters a regenerative heaterthrough the regenerative steam extraction pipeline; exhaust gas of the small steam turbine enters the converging header; the exhaust gas of the small steam turbine enters the regenerative heater through the regenerative steam extraction pipeline adjusting valve; extracted steam from a main steam turbine enters the converging header through a regulating valve; the converging header is connected with a condenser through the regulating valve; and the extracted steam from the main steam turbine is connected with the regenerative steam extraction pipeline adjusting valve through the regulating valve and enters the regenerative heater. According to the system and method, start-stop of the small steam turbine and back pressure stable control of normal operation can be ensured, and effective steam extraction and backheating of the feed water heater are carried out while the small steam turbine normally drives the feed water pump.

The invention discloses a method and a control device for recycling potential energy of a movable arm of an excavator. When the movable arm descends, first-stage pressure boosting can be realized in a controlled manner according to difference between the area of a rodless cavity of an oil cylinder of the movable arm and the area of a rod cavity of the oil cylinder of the movable arm, then second-stage pressure boosting is realized via a pressure boosting cylinder, the potential energy generated during descending of the movable arm can be converted into high-pressure energy through the two stages of pressure boosting, and the high-pressure energy is stored in an energy accumulator; and when the energy is released, high-pressure oil stored in the energy accumulator is led into an oil inlet of a rotation control valve in a controlled manner, pressure oil in the energy accumulator is led into a rotation motor through the rotation control valve, and rotation operation can be carried out. By the method and the control device for recycling the potential energy of the movable arm of the excavator, the energy can be reused, designing, manufacturing and overall arrangement of the pressure boosting cylinder are facilitated, and the energy of the energy accumulator can be released and used.

A variable displacement plunger pump system for a drilling rig, including an integrated control valve group, a plunger pump, a rotary motor, and an up and down motor, wherein the integrated control valve group is a slice valve, and the one-way regulating valve body, the rotary motor control valve , The upper and lower motor control valves correspond to the corresponding oil hole positions of the one-way pressure reducing valve body, so that the main oil circuit and the control oil circuit are connected, and the valves are connected in series with screws, and then the oil pipe and the pressure limiting flow control valve body are used. Connect, and finally connect with the plunger pump as a whole. The advantages are: the shape is flaky, and the control valve core with various functions and the corresponding oil circuit can be installed inside according to the needs. There is no pipeline connection with the hydraulic system, and the oil return hole of the integrated control valve is directly connected to the oil inlet hole of the plunger pump, which has the function of hydraulic power recovery. The main oil circuit cancels the hydraulic loss components of the overflow valve and the throttle valve, and the drilling rig has good controllability and stability. stability.

The invention discloses a hybrid power hydraulic excavator system adopting movable arm closed control, comprising an internal combustion engine, a multitandem valve bank, a variable displacement hydraulic pump, a generator, an electric energy storage unit, a movable arm control system, a rotation control system, a bucket hydraulic cylinder and a bucket rod hydraulic cylinder, wherein a motor with variable rotation speed is used for driving the hydraulic pump with three oil ports to directly control a movable arm hydraulic cylinder, so that the vertical movement of a movable arm of a hydraulic excavator is realized; the rotation of the upper rotation main body of the hydraulic excavator relative to the lower rotation main body is realized through controlling a rotation motor / generator by the rotation control system; a hybrid power drive mode is adopted, the potential energy of the movable arm and the kinetic energy of rotation can be directly converted into electric energy to be stored in the electric energy storage unit. According to the hybrid power hydraulic excavator system adopting movable arm closed control, the recycle and release of the potential energy of the movable arm are conveniently controlled, and the system has the advantages that the energy efficiency is high, the structure is simplified, the fuel consumption of a whole machine is low, the work efficiency and the energy utilization are high, and the like.

The invention discloses a vehicle anti-skid control method and system. The control method comprises the steps: obtaining speed coefficients of wheel assemblies, wherein each wheel assembly is correspondingly connected to one electric proportional hydraulic motor; using the average value of the speed coefficients of all the wheel assemblies as a reference average speed coefficient; obtaining the speed difference coefficient of the wheel assembly, wherein the speed difference coefficient of the wheel assembly is the difference value between the speed coefficient of the wheel assembly and the reference average speed coefficient; and judging whether the wheel assembly slips or not according to the speed difference coefficient of the wheel assembly, and if yes, reducing the displacement of the electric proportional hydraulic motor connected with the wheel assembly. According to the method, speed reduction control is conducted on the wheel assembly with the slipping problem, speed reduction of the wheel assembly is achieved by reducing the motor displacement of the electric proportional hydraulic motor connected with the wheel assembly, additional valve sets can be reduced, the cost is reduced, and the working efficiency of the hydraulic system is improved.