34 results about "Stability loss" patented technology

An electric assisted steering system for a motor driven road vehicle, having assist torque signal generating means which generates an assist torque signal for the steering system in response to the driver's applied torque and sensed vehicle speed to reduce the driver's steering effort. A yaw rate haptic torque is generated which is based upon vehicle rate error and is arranged to be added to the torque assist signal such that, when the yaw rate error builds up corresponding to increasing steering instability (e.g. understeer or oversteer) of the vehicle, the haptic torque added to the torque assist signal reduces the effective road reaction feedback sensed by the driver in advance of any actual vehicle stability loss whereby to allow the driver to correct appropriately in good time before terminal steering instability is reached. Alternatively, the haptic torque can be based upon vehicle lateral acceleration which is arranged to be subtracted from the torque assist signal such that when vehicle lateral acceleration builds up, corresponding to tighter cornering of the vehicle, the haptic torque subtracted from the torque assist signal increases the effective road reaction feedback sensed by the driver corresponding to the increase in cornering forces generated by the tyres of the vehicle.

The invention provides a method for making interconnected network transient stability emergency control strategies based on inter-region tie line measurement. The method comprises the following steps that 1, an off-line control strategy is made, tie lines among important regions are recorded, and the emergency control strategies for all regions of an interconnected network are made by means of fault setting; 2, relative power angles among the regions are calculated, in the actual operation process of the interconnected network, a PMU is used for collecting real-time voltage values of the tie lines of all the regions, and the relative power angle between every two regions is calculated; 3, the region where a unit disturbed most severely is located is judged, and according to real-time information of the relative power angles among the regions, contrastive analysis is carried out to determine the position where the unit disturbed most severely in the interconnected network is located; 4, emergency generator tripping control is implemented, and according to the area where the unit disturbed most severely is located, the specific off-line generator tripping control strategy is executed to prevent transient state stability loss of the system. The method has the advantages that the needed measurement amount is small, the calculation amount is small, and the method is suitable for the large region interconnected network and high in pertinence.

The invention relates to an early warning method for pneumatic stability loss of turbines. The method comprises the following steps of: setting a dynamic pressure sensor at the wall surface of a case of a turbine to acquire wall surface static pressures generated by blades and record a dynamic pressure signal; carrying out real-time calculation through sapling points in the current rotor period and in the previous rotor period to obtain a periodic coefficient Rc of the current sampling point; obtaining a periodic coefficient Rc before the current sampling point through the sampling point in the previous rotor period and in the one before the previous rotor period, and doing the rest I the same manner to continuously obtain periodic coefficients Rc; setting a threshold value Rcth, and calculating the probability F (Rcth) that the periodic coefficient Rc in the previous statistical window before the current sampling point is less than or equal to Rctch; presetting an early warning value of a working margin, comparing the probability F (Rcth) with the early warning value, and when the probability F (Rcth) is greater than the early warning value, generating an early warning signal. The early warning method for pneumatic stability loss of turbines, stall early warning signals can be given earlier.

The invention relates to a method for cooling peripheral frozen earth and preventing water catchment in an excavation pit for a permafrost region. The method is characterized in that a pit slot is excavated at a position which is 0.5-5 m far away from the rim of the designed pit; the slot depth is a depth being 0-100 cm below underground permafrost table; a cooling pipe is paved at the bottom of the pit slot; a waterproof film is paved on the cooling pipe, the bottom of the slot, and the wall of the pit to a ground surface, and refilled and punned with filled earth; and the cooling pipe injected with circular freezing liquid is connected with a refrigerator on the ground surface through a hose. Shown by practices, with the adoption of the method provided by the invention, the problems of melting and stability loss of the frozen earth and the frozen earth in the excavation pit in a warms-season construction process and water leakage and water collection of underground water can be solved through the effective combination of refrigeration and water insulation, so that the permafrost stability can be effectively protected, and the normal construction and the long-term stability of the Qinghai-Tibet direct-current networking engineering in the permafrost region can be ensured.

The invention discloses an automatic control system and method for the stability loss of a train bogie. The control system comprises a control module, a bogie stability loss detection module, a speed detection module and a braking module, wherein the bogie stability loss detection module, the speed detection module and the braking module are connected with the control module. The bogie stability loss detection module is used for detection and used for sending bogie state information to the control module. The speed detection module is used for detection and used for sending speed information of a train to the control module. The braking module is used for braking the train according to a braking command of the control module. The control method includes the steps that multiple speed limit values are preset, the speed limit values are divided into different grades from high to low according to the speed limit values, and the speed limit values at the high grades are larger than those at the low grades; and when the train bogie loses stability, through braking, the train is made to run with the speed limit value reduced by one grade. The system has the beneficial effects that the automation degree is high, the response speed is high, manual intervention is not needed, the stability loss of the train bogie can be rapidly eliminated, the train bogie stability loss control accuracy is improved, and the safe running of the train is guaranteed.