The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper deals with a voltage disturbance generator output characteristics. Usually a microgrid is connected to utility grid through STS to disconnect in case of fault occurrence. The STS should be opened in case of outage, however, it may be connected in case of voltage sag occurrence. The magnitude of surge or over current through the STS is determined by the dip of the sag. The voltage disturbance...
This paper discussed the tuning process of the power system stabilizer (PSS) for a nuclear turbine-generator excitation system. By measuring the non-compensated phase-frequency characteristic of the excitation without PSS, and through calculation and critical gain test, the PSS parameters are determined. Through step response and anti-regulation experiment, the effectiveness of the PSS is verified.
STATCOMs provide grid with not only reactive power compensation but auxiliary stability support through exerting influence on the dynamic behavior of Synchronous Generator (SG) during grid power oscillations. In this paper, method of electrical torque analysis is utilized to analyze the mechanism of STATCOM affecting the transient performance of SG when operates in power oscillations suppression mode,...
The integration of Distributed Energy Resources (DER), μ-grids, Electric Vehicle (EV) charging, aggregated demand response and customer participation in the power market, has led to unprecedented dynamic behaviors and complication in the electric power system operations. With the introduction of Phasor Measurement Units (PMU), wide area monitoring and controls are feasible. In this paper, a stochastic...
A low latency Vernier delay-line-based window ADC capable of simultaneous quantization for digital control single-inductor-multiple-output (SIMO) DC-DC converter is proposed in this work. The ADC converts signals of feedback voltages and sensed inductor current by voltage-time converter (VTC) and successive time-digital converter (TDC). Together with a subrange quantization scheme, a preceding interleaving...
A square wave transmission based micro-grid, which is compatible with commercial AC sinusoidal grid components, is investigated in this paper for rural areas. The basic interface circuit unit, square wave generator (SWG) is designed to satisfy bidirectional power flow and square wave transfer. The square wave has larger power delivery compared to sine wave. The circulating current of paralleled SWGs...
Prototyping and proper testing of the electrical control unit of more electric aircraft (MEA) under various load profiles and fault conditions is necessary to ensure the performance of the controller. In order to solve the problems such as complicated operation, high experiment cost and long development period in aircraft power system traditional test method, this paper presents a semi-physical real-time...
In a large ship, Power Management System (PMS) which manages power system should be tested in various operating conditions and fault situations. During its function tests, the PMS should be connected to the ship's power system. However, the test has limitations due to cost, test condition and safety. In this paper, a control Hardware-in-the-Loop Simulation (HILS) system is proposed for the function...
The controller design of servo drives for bandwidth improvement will presented in this paper. The delay issues caused by calculation, fdter and PWM generation, etc. are addressed. The controllers of current loop, speed loop and position loop are designed considering the delay and phase margin. Experimental results show the bandwidth for current, speed and position loops of servo drives are significantly...
Traction application inverter runs in very low switching frequency to reduce switching losses, whereas in case of PMSM as traction applications, there is not a the whole speed range strategy can not only achieve synchronized SVPWM modulation but also transit to six-step mode. Based on zero-sequence voltage injection SVPWM, synchronized modulation and over-modulation methods, this paper put forward...
Power packaging technology plays an important role to achieve high performance for high voltage (HV) generator. The HV generator packaging techniques are systematically classified according to different component level packaging and system assembly technology. Both component level packaging and system assembly technology are included in the review and their advantages and disadvantages are discussed...
This article presents the efficiency analysis of a 5 MW wind turbine generating system in an all-DC wind park comprising of a permanent magnet assisted synchronous reluctance generator (PMaSynRG) system as well as an IGBT equipped forced-commutated inverter. In this article, the focus is on the NPC converter and DC-DC converter with an optimized high-frequency transformer. The total efficiency through...
With the increasing size of the wind farms, the impact of the wake effect on the energy yields and lifetime consumption of wind turbine can no longer be neglected. In this paper, the affecting factors like the wind speed and wind direction are investigated in terms of the single wake and multiple wakes. As the power converter is the most fragile component among the turbine system, its lifetime estimation...
In the power grid lacking conventional power sources for black start, adopting wind farm as a power source for black start is a beneficial attempt. With Jangsu local power grid as research object in China, and combining with the special geographical and demand of the local power grid, a black start scheme using permanent-magnet synchronous generator(PMSG)-based wind farm as black start power is proposed...
Load frequency control in an islanded microgrid is challenging due to the low system inertia and random power variations resulting from renewable energy sources and loads. The traditional droop control mechanism may become unstable under some conditions. To overcome this problem a new control algorithm is proposed in this paper. The necessary condition derived to ensure the frequency stability is...
This paper proposes a new variable field wind generator with soft magnetic composite material and the basic theories were presented. Basically, the overlapping of the two magnetic fields is applied to its machine operation. The fundamental theory of the new wind generator is the same as traditional generators. Its bias of magnetic fields and two stator partitions increase iron and copper losses. Soft...
This paper investigates the dispatch of diesel generators in Kinmen Island power system with wind power generators. Because wind conditions are somewhat unpredictable, it is difficult to provide a stable base load of power to the grid from wind energy. To ensure an adequate supply of energy at all times, wind energy needs to be combined with other sources. To know the dynamic behavior of the system,...
This paper proposes a frequency regulation strategy applied to wind turbine generators (WTGs) in an isolated grid. In order to complement active power shortage caused by sudden load or wind speed change, an improved deloading method is proposed to solve inconsistent regulation capabilities in different speed regions and provide WTGs a certain capacity of power reserves. Considering the torque compensation...
This paper proposed new position control method with acceleration feedforward compensation under the limited control bandwidth in the position control system of the EGR valve. This method estimates the acceleration reference through analysis of the relation between position controller output and speed reference without pattern and differential. The proportional gain of the position controller and...
This paper proposes a control method to expand a fault-ride-through (FRT) operation range for a grid-tied matrix converter. In the conventional method, the generator current is limited because the q-axis current is only controlled whereas the d-axis current is kept to zero. Consequently, the matrix converter cannot satisfy the FRT requirements for the grid reactive current due to the limitation of...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.