An Optimal Speed Control Method of Multiple Turboshaft Engines Based On Sequence Shifting Control Algorithm

2021 ◽  
Author(s):  
Yong Wang ◽  
Changpeng Cai ◽  
Jie Song ◽  
Haibo Zhang
Keyword(s):  
Control Algorithm ◽  
Control Method ◽  
Fixed Ratio ◽  
Speed Control ◽  
Optimization Method ◽  
Engine Fuel ◽  
Significant Drop ◽  
Optimal Speed ◽  
Power Turbine ◽  
Turbine Speed

Abstract In order to overcome the problem of significant drop in operational efficiency remarkably while power turbine speed varies among a large range, an optimal speed control method of multiple turboshaft engines based on sequential shifting control (SSC) algorithm is proposed. Firstly, combined with multi-speed gearboxes, a sequential shifting control algorithm of multiple turboshaft engines is proposed and designed to accomplish continuously variable speed control. Then, selecting the minimum engine fuel flow as the optimization objective, an integrated optimization method of optimal speed based on multiple engines and multi-speed gearboxes is proposed to promote the operational economy. Finally, the simulation tests of the optimal speed control method of twin and triple turboshaft engines is conducted separately. The results demonstrate that the optimal speed control method of multiple turboshaft engines based on SSC algorithm can change the power turbine speeds by no more than 7% and main rotor speed by over 8% simultaneously. In addition, compared with the fixed-ratio transmission (FRT), engine fuel flows decrease by more than 2% under different cruise states. It proves that the optimal speed control method is beneficial to obtain more superior overall performances of the integrated helicopter/multi-engine system without considerable loss of compressor surge margin.

scholarly journals Finite-Time Speed Control of Marine Diesel Engine Based on ADRC

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Yuanqing Wang ◽  
Guichen Zhang ◽  
Zhubing Shi ◽  
Qi Wang ◽  
Juan Su ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Finite Time ◽  
Fuel Injection ◽  
Control Method ◽  
Speed Control ◽  
Marine Diesel Engine ◽  
Engine Fuel ◽  
Control Effect ◽  
Finite Time Convergence ◽  
Marine Diesel

In this paper, in order to handle the nonlinear system and the sophisticated disturbance in the marine engine, a finite-time convergence control method is proposed for the diesel engine rotating speed control. First, the mean value model is established for the diesel engine, which can represent response of engine fuel injection to engine speed. Then, in order to deal with parameter perturbation and load disturbance of the marine diesel engine, a finite-time convergence active disturbance rejection control (ADRC) is proposed. At the last, simulation experiments are conducted to verify the effectiveness of the proposed controller under the different load disturbances for the 7RT-Flex60C marine diesel engine. The simulation results demonstrate that the proposed control scheme has better control effect and stronger anti-interference ability than the linear ADRC.

Application of Single Neuron PID Control Based on Variable Scale Algorithm in Tar-Ammonia Separation

2010 ◽  
Vol 139-141 ◽  
pp. 1945-1949
Author(s):  
Tian Pei Zhou ◽  
Wen Fang Huang
Keyword(s):  
Pid Control ◽  
Control Algorithm ◽  
Single Neuron ◽  
Control Method ◽  
Optimization Method ◽  
Separation Process ◽  
Control Effect ◽  
Environment Change ◽  
Good Convergence ◽  
Single Neuron Pid

In the process of recycling chemical product in coking object, ammonia and tar were indispensable both metallurgy and agriculture, so the control of separation process for tar-ammonia was one of the most important control problems. Due to the density difference between the tar and ammonia was greater, easier to separate, the control method based on PID was used in field at present. But the control effect of traditional PID was not good because of environment change and fluctuation in material composition. Separation process for tar-ammonia was analyzed firstly, in view of the shortcoming of traditional PID control algorithm, single neuron PID control algorithm based on variable scale method was adopted through using optimization method. Detailed algorithm steps were designed and applied to tar-ammonia separation system. Simulation results show that by comparison with traditional PID algorithm, the algorithm have the following advantages: faster learning speed, shorter adjusted time and good convergence performance.

Heavy-duty truck platooning on hilly terrain highways: Methods for assessment and improvement

2021 ◽  
pp. 095440702110676
Author(s):  
Miles J Droege ◽  
Brady Black ◽  
Shubham Ashta ◽  
John Foster ◽  
Gregory M Shaver ◽  
...  
Keyword(s):  
Control Method ◽  
Control Strategies ◽  
Speed Control ◽  
Vehicle Speed ◽  
Heavy Duty ◽  
Cruise Control ◽  
Hilly Terrain ◽  
Optimal Speed ◽  
Look Ahead ◽  
Shifting Strategy

Platooning heavy-duty trucks is a proven method to reduce fuel consumption on flat ground, but a significant portion of the U.S. highway system covers hilly terrain. The effort described in this paper uses experimentally gathered single truck data from a route with hilly terrain and an experimentally-validated two-truck platoon simulation framework to analyze control methods for effective platooning on hilly terrain. Specifically, this effort investigates two platoon control aspects: (1) the lead truck’s vehicle speed control and (2) the platoon’s transmission shifting algorithm. Three different types of lead truck speed control strategies are analyzed using the validated platoon model. Two are commercially available cruise control strategies – conventional constant set speed cruise control (CCC) and flexible set speed cruise control (FCC). The third lead truck speed control strategy was developed by the authors in this paper. It uses look-ahead grade information for an entire route to create an energy-optimal speed profile for the lead truck which is called long-horizon predictive cruise control (LHPCC). Then, a two-truck platoon transmission shifting strategy that coordinates the shift events – Simultaneous Shifting (SS) – is introduced and compared to a commercially available shifting strategy using the validated platoon model. This shifting strategy demonstrates further improvements in the platoon performance by improving the platoon gap control. A summary of these simulations demonstrates that the performance of the platoon can be improved by three methods: adding speed flexibility to the lead truck speed control method, using look-ahead road grade information to generate energy-optimal speed targets for the lead truck, and coordinating the timing of the transmission shifts for each truck in the platoon.

A new control method of rotor re-suspension after short failure of active magnetic bearing system

2018 ◽  
Vol 32 (34n36) ◽  
pp. 1840077
Author(s):  
Yi-Li Zhu ◽  
Yan-Hong Zhang ◽  
Yi-Lin Liu
Keyword(s):  
Control Algorithm ◽  
Position Control ◽  
Control Method ◽  
Speed Control ◽  
Magnetic Bearing ◽  
Active Magnetic Bearing ◽  
Dynamic Responses ◽  
Control Mode ◽  
Collision Force ◽  
Amb System

As it is difficult for traditional control method to realize rotor resuspension after short failure of Active Magnetic Bearing (AMB) system, a new control method containing rotor collision force evaluation algorithm module, rotor position control algorithm module and rotor vibration speed control algorithm module was proposed. Through the evaluation of rotor collision force, the controller automatically selects rotor positon control mode or rotor speed control mode. Based on rigid rotor theory, rotor dynamic model was established to analyze the dynamic responses after short failure of AMB system utilizing different control method. The results proved that the proposed control method can successfully realize rotor re-suspension.

Constrained Tracking Control by Gain-Scheduled Feedback With Optimal State Resets: A General Servo Problem and an Online Optimization Method

2016 ◽  
Vol 138 (12) ◽  
Author(s):  
Nobutaka Wada ◽  
Hidekazu Miyahara ◽  
Masami Saeki
Keyword(s):  
Tracking Control ◽  
Control Algorithm ◽  
Optimization Problem ◽  
Control Method ◽  
Actuator Saturation ◽  
Tracking Error ◽  
Reference Signal ◽  
Optimal Solution ◽  
Optimization Method ◽  
Experimental Result

In this paper, a tracking control problem for discrete-time linear systems with actuator saturation is addressed. The reference signal is assumed to be generated by an external dynamics. First, a design condition of a controller parameterized by a single scheduling parameter is introduced. The controller includes a servo compensator to achieve zero steady-state error. Then, a control algorithm that guarantees closed-loop stability and makes the tracking error converge to zero is given. In the control algorithm, the controller state as well as the scheduling parameter is updated online so that the tracking control performance is improved. Then, it is shown that the decision problem of the scheduling parameter and the controller state can be transformed into a convex optimization problem with respect to a scalar parameter. Based on this fact, we propose a numerically efficient algorithm for solving the optimization problem. Further, we propose a method of modifying the control algorithm so that the asymptotic tracking property is ensured even when the numerical error exists in the optimal solution. A numerical example and an experimental result are provided to illustrate effectiveness of the proposed control method.

Optimized Steam Turbine Operation by Controlled Clutch Angle Engagement

2015 ◽  
Author(s):  
Gerta Zimmer ◽  
Daniel Pieper ◽  
Kees van Driel ◽  
Bernd Lacombe ◽  
Mirko Daenner ◽  
...  
Keyword(s):  
Simulation Model ◽  
Steam Turbine ◽  
Control Algorithm ◽  
Control Method ◽  
Parameter Uncertainties ◽  
Electrical Grid ◽  
Engagement Angle ◽  
Turbine Shaft ◽  
Run Up ◽  
Turbine Speed

Some single shaft CCPPs are known to display increased vibrations if engaged at certain angles and a very smooth operational behavior if engaged at other angles. Neither the reason nor a mechanical mitigation for this behavior is known. Roughly, the engagement angles can be clustered into four 90° sectors, one of them is deemed unfavorable and another one is classified as favorable with respect to vibrations of the overall power train shaft. Although the first priority is to have an assembly that runs smoothly at arbitrary engagement angles, an option to engage at a predefined ‘good’ angle provides an I&C back-up solution to avoid undue vibrations. To meet this requirement a control method was developed to run up the steam-turbine thus that it will engage at a pre specified angle. The basic idea of the developed control algorithm is to increase the acceleration of the steam-turbine during run up if a prediction reveals an engagement angle that would be too small to be within the desired area and, conversely, decrease the acceleration if the anticipated angle would be too large. A control algorithm to exploit this idea was developed and tested with the aid of a simulation model. The simulation model comprises a detailed thermodynamic model of the steam-turbine, the control valves and their actuators, the steam-turbine shaft and the shift clutch. I&C was modelled with all details relevant to turbine speed control. The gas-turbine/generator unit, however, is cut down to angular velocity and relative angle, respectively. The performance of the controller was validated to comply with parameter uncertainties, different sampling times and frequency fluctuations of the electrical grid during coupling. In parallel, a high precision angular measurement device was developed and integrated into the existing turbine I&C. Hardware-in-the-loop tests with simulated turbines and a hardware I&C system implementation also revealed a very satisfactory performance. On site implementation of a prototype was successfully accomplished and resulted in the predicted accuracy of the preset engagement angle.

Speed regulation control of tractors’ new dual-flow transmission system based on slip rate resistance classification

2021 ◽  
pp. 095440702110105
Author(s):  
Guang Xia ◽  
Yan Xia ◽  
Xiwen Tang ◽  
Linfeng Zhao ◽  
Baoqun Sun
Keyword(s):  
Control Strategy ◽  
Control Algorithm ◽  
Production Efficiency ◽  
Sliding Mode ◽  
Slip Rate ◽  
Speed Control ◽  
Working Environment ◽  
Vehicle Speed ◽  
Speed Change ◽  
Simulation Results

Fluctuations in operation resistance during the operating process lead to reduced efficiency in tractor production. To address this problem, the project team independently developed and designed a new type of hydraulic mechanical continuously variable transmission (HMCVT). Based on introducing the mechanical structure and transmission principle of the HMCVT system, the priority of slip rate control and vehicle speed control is determined by classifying the slip rate. In the process of vehicle speed control, the driving mode of HMCVT system suitable for the current resistance state is determined by classifying the operation resistance. The speed change rule under HMT and HST modes is formulated with the goal of the highest production efficiency, and the displacement ratio adjustment surfaces under HMT and HST modes are determined. A sliding mode control algorithm based on feedforward compensation is proposed to address the problem that the oil pressure fluctuation has influences on the adjustment accuracy of hydraulic pump displacement. The simulation results of Simulink show that this algorithm can not only accurately follow the expected signal changes, but has better tracking stability than traditional PID control algorithm. The HMCVT system and speed control strategy models were built, and simulation results show that the speed control strategy can restrict the slip rate of driving wheels within the allowable range when load or road conditions change. When the tractor speed is lower than the lower limit of the high-efficiency speed range, the speed change law formulated in this paper can improve the tractor speed faster than the traditional rule, and effectively ensure the production efficiency. The research results are of great significance for improving tractor’s adaptability to complex and changeable working environment and promoting agricultural production efficiency.

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