4 results about "Dc motor speed control" patented technology

This invention provides a DC motor speed control system for a condensing unit based on pressure detection, including a condenser, a compressor, a high-pressure sensor, an ambient temperature sensor, and a control device. The high-pressure sensor detects the pressure in the high-pressure pipe of the condenser according to a preset cycle and sends the detected high-pressure value to the control device. The control device adjusts the speed of the DC motor based on the high-pressure value. The control system provided by this invention, by detecting the high-pressure of the condenser, adjusts the fan speed in real time according to the current operating pressure of the condenser, thereby maintaining the condenser in a normal operating environment. This overcomes the problem of misjudging the condenser's heat dissipation needs under low-temperature operating conditions and avoids frequent triggering of high-pressure switches or low-pressure protection by the condensing unit.

The invention discloses a control method for a brushless direct current motor of an industrial sewing machine. The control method comprises the following steps: step 1, designing the structure of the brushless direct current motor of the industrial sewing machine; 2, setting a brushless direct current motor rotating speed control method based on the whale algorithm optimization PID; 3, designing software and hardware of a brushless direct current motor control system; according to the industrial sewing machine numerical control system parameter design method, by designing the structure of the industrial sewing machine brushless direct current motor, rotating speed control, control system software and hardware and the numerical control system parameters, the control performance is greatly improved, and meanwhile the purposes of low carbon and energy saving are achieved. Meanwhile, the stability, rapidity and accuracy of the system are improved, and needle stopping is rapid and accurate.

This invention discloses a DC motor speed control identification method and system based on an improved quasi-Newton method, belonging to the technical field of DC motor speed control system modeling. First, a time-varying nonlinear DC motor speed control system is constructed, and an identification model of this system is obtained. Then, an identification method flow based on the quasi-Newton method under step-size line search is constructed. The optimal step size is obtained through step-size line search for parameter estimation, and a correction strategy is designed to ensure the positive definiteness of the approximation of the Hessian matrix inverse. This invention avoids the oscillation or slow convergence problems caused by a fixed step size by dynamically adjusting the step-size factor, and simultaneously introduces a correction strategy to forcibly guarantee the positive definiteness of the approximation of the Hessian matrix inverse, thereby obtaining more accurate motor model parameters.

This invention discloses a design method for a hyperbolic tangent attraction law in a discrete-time sliding mode controller for a DC motor speed control system. Based on the hyperbolic tangent function, a discrete-time hyperbolic tangent attraction law is constructed. Hyperbolic tangent-type adaptive interference compensation measures are embedded into the discrete-time hyperbolic tangent attraction law to construct a discrete-time hyperbolic tangent attraction law with interference compensation capability, thereby designing a discrete-time sliding mode controller. The output signal is then calculated as the control input signal for the DC motor speed control system, enabling the system to follow the given speed signal. The design method for the hyperbolic tangent attraction law in a discrete-time sliding mode controller provided by this invention features fast convergence and chatter-free characteristics, while also improving the tracking accuracy, anti-interference capability, and effectively reducing output speed fluctuations in the DC motor speed control system.