58results about How to "Less control variables" patented technology

The invention discloses a three-degree-of-freedom mixing conical and radial magnetic bearing, and belongs to the field of magnetic suspension bearings. The three-degree-of-freedom mixing conical and radial magnetic bearing is composed of a radial magnetic bearing body and a conical magnetic bearing body; an axial magnetization annular permanent magnet or annular bias winding is arranged between the radial magnetic bearing body and the conical magnetic bearing body to provide biased magnetic flux; a radial magnetic bearing stator is of a salient pole structure and provided with four teeth; each stator tooth is wound with a coil, and every two coils are connected to form two radial suspension windings; a rotor is of a cylinder structure; the conical magnetic bearing body comprises two conical stators and two conical rotors which are each of a conical cylinder structure; an axial suspension winding is embedded between the two conical stators; the radial stator, the two conical stators and the permanent magnet are connected through a magnetic conductive ring; and the radial rotor and the two conical rotors are sleeved with a rotor magnetic conductive ring and then a rotary shaft. Control magnetic circuits of the radial magnetic bearing body and the conical magnetic bearing body are isolated, axial force and radial force are decoupled, control is simple, the structure is compact, the three-degree-of-freedom mixing conical and radial magnetic bearing can be applicable to electromagnetic bearings or permanent magnetic bias type magnetic bearings, and universality is good.

The invention discloses a conical magnetic suspension switch reluctance motor and a control method. The motor consists of a switch reluctance motor and two conical magnetic bearings; bias windings of the two conical magnetic bearings are connected with a winding of the switch reluctance motor in series to form a three-phase torque winding; two radial suspension windings of each conical magnetic bearing control suspension of two degrees of freedom, so that four radial degrees of freedom is formed and decoupling control can be realized; the axial suspension windings of the two conical magnetic bearings are connected together in series to form one axial suspension winding to control axial suspension; the motor can independently control torque winding current and turn-on and turn-off angles of the power circuit, and can control rotary speed and torque in real time; current of five suspension windings is controlled, suspension force in five directions can be adjusted in real time, and suspension of five degrees of freedom can be further realized; and the motor and the control method disclosed by the invention are high in integration degree, less in control variables and simple in suspension control, and the power converter of the suspension system is low in cost.

The invention discloses an optimal Bingham number control method for the impact working condition of an automobile electric control damping suspension system, and the method depends on hardware including the automobile electric control damping suspension system, a displacement sensor and a force sensor. The method comprises the following steps: 1) establishing an automobile suspension system dynamic model under an impact working condition according to mechanical characteristics of an automobile suspension in a stretching and compressing state; 2) calculating the motion state of the electrically-controlled damping suspension under impact excitation by utilizing the kinetic model and the initial conditions of suspension control, and calculating the optimal Bingham number and the corresponding expected force in the compression and springback process; 3) based on the multi-operator model, establishing a nonlinear mechanical model of the automobile electric control damping actuator; and 4) tracking the expected force through an electric control damping actuator nonlinear mechanical model, and calculating the optimal output power matched with the optimal Bingham number. According to the invention, the self-adaptive control of impact buffering can be quickly and accurately realized, so that the structural damage of impact excitation to a vehicle body / frame structure and a driver and passengers can be effectively reduced.

The invention relates to an aggregate grading design method for improving the strength of a cement-emulsified asphalt mixture. The method comprises the steps of determining multiple stages of screen hole sizes of target gradation, a grading upper limit corresponding to each stage of screen hole sizes, and a grading lower limit corresponding to each stage of screen hole sizes; carrying out linear fitting to obtain a straight line I: Log P upper (x)=a Log (x / xmax)+b, and a straight line II: Log P lower (x)=c Log (x / xmax)+d; making n+1 straight lines with slopes which are respectively K1, K2, K3, K4, K5,... and Kn+1; making grading curves which respectively correspond to the n+1 straight lines, and determining the best grading curve from the grading curves. The method involved in the invention avoids idealized conception in the traditional method, and is closer to practical engineering application.

The invention relates to an aggregate grading design method for improving the strength of a cement-emulsified asphalt mixture. The method comprises the steps of determining multiple stages of screen hole sizes of target gradation, a grading upper limit corresponding to each stage of screen hole sizes, and a grading lower limit corresponding to each stage of screen hole sizes; carrying out linear fitting to obtain a straight line I: Log P upper (x)=a Log (x / xmax)+b, and a straight line II: Log P lower (x)=c Log (x / xmax)+d; making n+1 straight lines with slopes which are respectively K1, K2, K3, K4, K5,... and Kn+1; making grading curves which respectively correspond to the n+1 straight lines, and determining the best grading curve from the grading curves. The method involved in the invention avoids idealized conception in the traditional method, and is closer to practical engineering application.

The invention discloses a five degrees-of-freedom conical magnetic levitation switch reluctance motor and a control method. The motor consists of a three-phase 12 / 8-pole switch reluctance motor and two conical magnetic bearings; the bias winding of one conical magnetic bearing and two windings in the A phase horizontal direction of the switch reluctance motor are connected in series while the biaswinding of the other conical magnetic bearing and the two windings in the A phase vertical direction are connected in series to form two channel A phase composite windings; a constant switch-on strategy is adopted to generate bias magnetic flux of the two magnetic bearings and to generate torque in the reluctance motor; the B and C phase winding structures in the switch reluctance motor in the motor are the same as that of the conventional switch reluctance motor, so that alternate excitation switch-on is performed to generate torque to realize rotary operation; by only controlling the current of the A phase two sets of windings and the current of four radial levitation windings, five suspension force can be controlled to realize the five degrees-of-freedom levitation; and the motor is high in system integration degree, high in magnetic utilization rate, simple in control and convenient to implement.

The invention belongs to the technical field of special steel plate preparation, and particularly provides a ferrite-martensitic double-phase hot-rolled pickling plate for wheel spokes and a preparation method thereof, the ferrite-martensitic double-phase hot-rolled pickling plate comprises the following components by weight: 0.05-0.07% of C, 0.40 to 0.60% of Si, 1.20% to 1.50% of Mn, less than orequal to 0.020% of P, less than or equal to 0.010% of S, 0.020%-0.070% of Alt, 0.30% to 0.40% of Cr, 0.10% to 0.20% of Mo, less than or equal to 0.006% of N and balance of Fe and unavoidable impurities. The ferrite-martensitic double-phase hot-rolled pickling plate adopts lower chromium and molybdenum contents, reduces the alloy cost, adopts a lower silicon content, reduces the difficulty of continuous casting production after steel making, improves the heat dissipation capacity and continuous casting ability of molten steel, and is beneficial to industrial mass production. By adopting of a two-stage cooling process, control variables are reduced, the operability and stability of the production are improved, and the coiling temperatureis appropriately increased to (350-400 DEG C). The higher the temperature, the lower the strength of the steel, and the loss of coiling equipment is reduced.

The invention discloses a control method of a composite rotor bearingless switched reluctance machine. A stator of the machine is of a salient pole structure and is provided with twelve stator teeth, each stator is only provided with a set of winding, a rotor comprises a salient pole rotor and a cylindrical rotor, the cylindrical rotor is used for generating a suspension force, and the salient pole rotor is provided with eight teeth and is used for generating a torque; in a suspension excitation section, four windings of each phase are independently controlled and are equivalent to a main winding and two suspension windings, and a calculation method of a main winding current and suspension winding currents with minimum winding copper loss is adopted; and in a torque excitation section, the four windings of each phase are jointly controlled, and the rotational speed and the torque are controlled in real time by controlling a chopping limit and a turn-off angle of a phase winding current. By the method, the torque control and the suspension force control are decoupled, coordination control is performed, the high-speed suspension property is good, the control variable is reduced, simple control and convenient implementation are achieved, and the copper loss in the suspension section is small.