36results about How to "Suppress power oscillations" patented technology

A network power oscillation suppressor based on photovoltaic batteries characterizes that it is a device for suppressing network power oscillation based on photovoltaic barriers, which converts solar energy into electric energy by a solar energy battery board and outputs DC voltage then to invert it to AC voltage to be transmitted to the network, in which, it can carry out active regulation to the network or carry out reactive regulation to the system since the inverter is composed of voltage source type quick switch off components and outputs part of active power to the network when operating normally and regulates active and reactive powers output by the oscillation suppressor based on the control rule when power oscillation happens to the network.

The invention relates to a method for restraining the torsional vibration of a rotor of a motor closed-loop speed control system. The method comprises the following steps: (1) collecting a revolving speed signal of the motor rotor through a signal collecting unit, and enabling the revolving speed signal to pass through a band pass filter unit to extract a torsional vibration component signal of the rotor; (2) enabling the torsional vibration component signal of the rotor to pass through a lead-lag unit to regulate the phase position of the torsional vibration signal, and obtaining an electromagnetic torque component signal being phase-opposite with the torsional vibration component signal of the rotor; and (3) regulating the gain amplification times of a gain amplification unit, adding the electromagnetic torque component signal into a revolving speed feedback point through an amplitude limiting unit to generate an electromagnetic torque component being phase-opposite with the torsional vibration signal of the rotor, and therefore effectively restraining the torsional vibration of the motor rotor and power vibration. According to the method, the divergent torsional vibration of the rotor can be restrained, meanwhile the power vibration due to the torsional vibration of the rotor can also be restrained, and the signal collection is simple and convenient. The method has the advantages of simple structure, lower cost, less regulation parameters, easiness in realization and the like and has a larger promotional value.

The invention relates to a power decoupling method of a virtual synchronous generator based on a virtual power of a single rotation angle. Since a fixed rotation angle is used in the virtual power conversion, it is not necessary to consider the impedance angle of the output impedance of the inverter. The sensitivity is small, the design is simple, and it is easy to implement; the inherent inertia structure in the virtual synchronous generator algorithm is used to solve the weak decoupling problem caused by the fixed rotation angle, which ensures the dynamic and static stability of the system; the present invention has high control precision, With good tracking effect, it can effectively suppress power oscillation and provide damping support for the power grid. It is suitable for new energy grid-connected systems such as solar power and wind power to be connected to medium and low voltage micro-grids. This method can weaken the coupling degree of the output power of the inverter when the system is connected to the medium and low voltage microgrid, thereby suppressing the oscillation of the output power, improving the dynamic and static stability of the entire inverter system, and ensuring its safe and reliable operation.

A grid-dominated voltage source converter amplitude and phase control method, first establishes multi-type power supply dynamic differential and microgrid algebraic equations, proposes a grid-dominated voltage source converter compensation control loop, and then establishes multi-type power supply and commutation In order to ensure the dynamic stability of the whole system, based on the transient energy function of the micro-increase rate model, the parameters of the compensation control loop and the adjustment of the amplitude and phase variables are designed to suppress multiple Power oscillations between types of power supplies.

The invention discloses a virtual synchronous generator control method and control device for an energy storage converter, which realizes that the damping power only works in the dynamic process of frequency fluctuation, and the damping power must be zero after the steady state, and it will not be affected by damping. The change of the coefficient affects the deviation of the steady-state active power, which ensures that the active power can track the command value according to the set droop ratio while suppressing the power oscillation; in addition, the energy storage converter can provide inertial support and off-grid At the same time of seamless switching, it has the ability of rapid control of the voltage and current loop, and the rapid control of the output current through the current loop is beneficial to reduce the current distortion and improve the power quality of the energy storage converter in grid-connected and island mode operation .

The invention discloses a grid-connected control method for multi-machine parallel virtual synchronous inverters. When each virtual synchronous inverter is connected in parallel to the main power grid, the obtained phase angle compensation amount and angular frequency synchronous compensation amount are used to facilitate The synchronization of each virtual synchronous inverter with the voltage of the main grid can be realized. In addition, the current virtual inertia of each virtual synchronous inverter is adjusted to the target virtual inertia by using the equivalent reactance and the maximum angular frequency compensation between each virtual synchronous inverter and the main grid, so as to suppress the The purpose of power oscillation between the generator and the main grid. Therefore, with this scheme, when each virtual synchronous inverter is integrated into the main grid, it not only ensures the synchronization between the output voltage of each virtual synchronous inverter and the voltage of the main grid, but also avoids that each virtual synchronous inverter cannot be incorporated The power oscillation problem caused by the main grid. In addition, the invention discloses a grid-connected control device for multi-machine parallel virtual synchronous inverters, which has the above effects.