69 results about "Limit load" patented technology

The invention provides a wind generating set variable pitch execution tracking supervision control system and method. A dynamic response process of a first-order variable pitch execution mechanism is introduced into a variable pitch execution error following algorithm, the deviation between an estimated variable pitch angle position and an actual variable pitch angle position is detected to judge whether a wind generating set encounters the condition that the variable pitch following error is continuously increased or not, if the variable pitch following error exceeds a set threshold value, the set enters shutdown operation, the situation that the set experiences the limit load is avoided to the maximum extent, and the operation safety of the set under the complex working condition is improved. A mode of estimating the variable pitch angle position is adopted, the control effect deviation caused by the fact that the characteristics of a variable pitch executing mechanism are not considered in a traditional mode is overcome, the dynamic response of the first-order variable pitch executing mechanism is innovatively combined into the variable pitch following error algorithm, and therefore the variable pitch following error and the trend situation are found out as soon as possible, and the control action is triggered to protect the set from adverse effects caused by pneumatic imbalance of an impeller.

The invention discloses a pile foundation self-balancing test device with a balance point compensation function and a test method. The test device comprises an upper pile section, a lower pile section, a pile body jack, a pile pulling device and a displacement measurement device. According to the pile foundation self-balancing test device with the balance point compensation function and the test method, the pile body jack is arranged between the top of the lower pile section and the bottom of the upper pile section, and the pile body jack is started firstly; step-by-step load applying and graded loading are conducted through the pile body jack, real-time loads are recorded through a load sensor, and the displacement of the upper pile section and the displacement of the lower pile section are measured through the displacement measurement device; when the lower pile section reaches a limit state firstly, the pile pulling device is started to apply pile pulling force to the upper pile section until the upper pile section reaches the limit state; when the upper pile section reaches the limit state firstly, a counterweight test block is applied to the top of the upper pile section, then the pile body jack continues to be loaded until the lower pile section reaches the limit state, and the pile foundation bearing capacity is calculated according to the limit load of the upper pile section and the limit load of the lower pile section. According to the pile foundation self-balancing test device with balance point compensation function and test method, the problem that a balance point is inaccurate can be solved, and the pile foundation bearing capacity can be accurately calculated.

A method for determining the position and polishing amount of a variable-pitch bearing soft belt of a wind turbine generator comprises the steps that a finite element model of a variable-pitch bearingconnecting system is set, and the deformation amount of a variable-pitch bearing under different limit loads and the deformation amount of the variable-pitch bearing under different fatigue loads arecalculated according to the model; and finally, the soft belt position and the polishing amount are determined according to the two sets of deformation amounts. The deformation of the bearing under the limit load and the deformation of the bearing under the fatigue load are calculated by establishing the finite element model of the variable-pitch bearing connection system, and the placement position of the soft belt and the polishing amount of the soft belt are determined by considering the deformation under two different loads, so that the obtained result is more reasonable.