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The vibration environment in which the vehicle runs is very complex, and impact vibration threatens the ride comfort and structural safety of the vehicle, and at the same time causes premature wear and fatigue damage to the vehicle components. Using TRIZ theory, the reasons for the lack of adaptability of the existing multidimensional frame excitation device are analyzed, and a multidimensional simulation test platform for frames and a supporting multidimensional vibration exciter are innovatively designed, which can achieve real-time position and direction adjustment of the excitation source and meet the needs of specific environments for different vibration effects. The overall frame can be disassembled and reused, which provides more effective data support for the optimization of frame structures of different dimensions. [ABSTRACT FROM AUTHOR]

The vibration environment in which the vehicle runs is very complex, and impact vibration threatens the ride comfort and structural safety of the vehicle, and at the same time causes premature wear and fatigue damage to the vehicle components. Using TRIZ theory, the reasons for the lack of adaptability of the existing multidimensional frame excitation device are analyzed, and a multidimensional simulation test platform for frames and a supporting multidimensional vibration exciter are innovatively designed, which can achieve real-time position and direction adjustment of the excitation source and meet the needs of specific environments for different vibration effects. The overall frame can be disassembled and reused, which provides more effective data support for the optimization of frame structures of different dimensions. [ABSTRACT FROM AUTHOR]

Accurate and timely fault diagnosis of the rotating rectifier for a wound-rotor synchronous starter/generator is of great importance to improve system reliability. In the generation mode of the system, there is one idle stator winding of the main exciter. The terminal voltage characteristic of the idle stator winding is analyzed, and a novel fault diagnosis method for the rotating rectifier in the generation mode of the system is proposed. In this method, two feature voltages, namely, the maximum peak voltage and any other peak voltage of the idle stator winding terminal voltage are extracted through voltage sequence reconstruction to calculate the feature ratio for fault detection. The corresponding rotor position obtained by an inherent position sensor where the maximum peak voltage occurs is collected to determine the faulty diode location. The experimental results verify the feasibility and effectiveness of the proposed fault diagnosis method.

Weak grid scenarios and low-inertia systems are emerging issues in power systems, which could lead to voltage and frequency instabilities. Synchronous Condensers (SynCons) have recently drawn renewed attention as a promising solution to provide system strength and inertia support. Even though the exciter control of SynCons is a well-established technology, further developments are required to guarantee the stability of post-fault operations, in particular, in weak grids. This paper proposes a data-driven approach for designing higher-order optimized exciter controllers to meet this requirement. A pseudo-random binary sequence (PRBS)-based system identification method is used to obtain frequency response data of the power system, from the exciter point of view, which is then fed into the proposed optimal control design procedure. The proposed exciter controller is tested for voltage ride-through and fault scenarios in a single machine infinite bus (SMIB) case and the IEEE 39-bus test system to assess its performance compared to the conventional AC1A exciter controller. The results obtained through simulation tests carried out using the PSCAD/EMTDC software verify that the proposed exciter controller guarantees the post-fault stability in both strong and weak grids.

A double electrical excitation synchronous generator (DEESG) with an embedded brushless exciter is proposed to achieve brushless excitation for a brush excitation electrical excitation synchronous generator (EESG). A set of extra stator excitation windings is placed in the stator slots with armature coils to generate a static magnetic field. There are two sets of windings on the rotor: pulsating excitation winding (Wp) and main excitation winding (WF). The winding direction of the coils of Wp and WF on the same rotor-pole-body is the same. The AC voltage of Wp which is induced by static magnetic field provides dc excitation current for WF by diodes. Both currents in the coils of the Wp and WF generate the rotor excitation flux which induces voltage in the armature coils. In this study, the operating principle is analyzed theoretically. The no-load and load characteristics are studied using Maxwell. The influence of the novel winding structure on the output voltage when the load varies is also analyzed. The voltage regulation rate of DEESG is reduced because the rotor excitation currents can be increased with armature current. A 1.5 kVA prototype is fabricated for experiment. The measured results agree well with the theoretical and FE-predicted results.

This article proposes a rotor position estimation method for brushless electrically excited synchronous starter/generator (BEESSG) at low speed region. Based on the multistage characteristics of BEESSG, two high frequency pulsating voltages with different frequencies are injected into phase $\alpha$ and phase $\beta$ of stator of the main machine simultaneously. The rotor position is estimated by the high frequency induced signals extracted from the stator windings of the main exciter through a position estimator. Low-pass filters are replaced by an auxiliary square wave sampling method to demodulate the rotor position from high frequency induced signals. Due to the amplitude unbalance of demodulated position related signals. A novel first quadrant definite integral method is proposed in this article for position compensation. Furthermore, the effectiveness and feasibility of the proposed method are verified by experimental results.

In this article, an exciter–quadrature–repeater transmitter pad is proposed in order to achieve high lateral misalignment tolerance and low leakage flux emission in electric vehicle wireless charging applications. In the proposed WPT system, a single half-bridge inverter unit is needed to energize the exciter coil, which is magnetically coupled to two larger quadrature repeater coils. The currents in the two repeater coils naturally adjust based on the lateral misalignment of the receiver pad to reduce the leakage flux density around the charging zone. The system can maintain zero phase shift between excitation voltage and current and achieve constant current charging conditions with fixed compensation capacitors in the ±150-mm lateral misalignment range. In order to verify the attributes of the proposed wireless power transfer (WPT) system, a 3-kW experiment setup with a 200-mm vertical gap was built and compared to a three-coil WPT system, which consists of a small transmitter coil, a single large repeater coil, and a receiver coil. According to the experiment results, even under extreme 150-mm lateral misalignment, the proposed WPT system has 90.7% coil-to-coil transmission efficiency. Furthermore, it achieves a 30% reduction of leakage flux density compared to the three-coil system in the 150-mm lateral misalignment case.

Fault detection of a rotating rectifier for a wound-rotor synchronous starter/generator (WRSSG) without a rotor position sensor in the stationary state is necessary for a successful engine start. Based on high-frequency (HF) voltage injection, a novel fault detection method of the rotating rectifier for the WRSSG in the stationary state is proposed. The rotating HF voltage is imposed on the stator windings of the main machine, and the HF feature current signal extracted on the stator windings of the main exciter is used for fault detection. In this article, the HF current signal in the main exciter with the rotating rectifier under different working conditions is analyzed first. To obtain the HF response current on the stator windings of the main exciter, the HF model of the WRSSG is analyzed. Through the Fourier series, the HF feature current signal together with fault detection is achieved. Compared with the existing fault detection methods, the proposed method shows no dependency on the rotor position information. Experimental results verify the feasibility and effectiveness of this method.

The present paper describes a theoretical and an experimental investigation of Clamped-Simply-Clamped-Simply supported isotropic rectangular plates subject to a large amplitudes forced transverse vibration. The theoretical model is based on Lagrange equations and the harmonic balance method which is used to obtain the non-linear algebraic equation of the problem. To examine our results, a test rig is designed and made. Furthermore, an electrodynamic exciter is used to provide the transverse harmonic vibrations, whereas an accelerometer measures the displacements. The approximate analytical solutions are obtained, and the experimental measurements are discussed and compared which are highlight the nonlinear hardening resonance.

Метою роботи є порівняльний аналіз параметрів діодного збудника безщіткового синхронного генератора середньої потужності від числа пар полюсів допоміжної електричної машини, розробка рекомендацій по вибору числа пар полюсів допоміжної електричної машини та конструкції збудника. Проводиться попередній електромагнітний розрахунок допоміжної електричної машини з урахуванням початкового значення відносної величини результуючої електрорушійної сили, допустимих значень індукцій на всіх ділянках магнітопроводу в режимі форсировки, визначаються довжина магнітопроводу і опори обмотки ротора. За наслідками розрахунку моделі випрямляча в квазісталому режимі роботи уточнюється відносна величина результуючої електрорушійної сили допоміжної електричної машини. Узгоджуються параметри допоміжної електричної машини, випрямляча, уточнюється довжина збудника в цілому. При збільшенні числа пар полюсів допоміжної електричної машини: зменшуються втрати в обмотках, маса міді і сталі; збільшуються втрати в сталі, індуктивний опір обмотки ротора; знижується якість вихідної напруги збудника. Рекомендується застосування допоміжної електричної машини, яка забезпечує найбільший коефіцієнт корисної дії збудника, найменшу потужність автоматичного регулятора збудження, найменшу загальну довжину збудника. The aim of the work is a comparative analysis of the parameters of the diode exciter of a brushless synchronous generator of medium power on the number of pole pairs of an auxiliary electric machine, the development of recommendations for choosing the number of pole pairs of an auxiliary electric machine and the design of the exciter. An improvement of the automated method of electromagnetic calculation of the exciter of a brushless synchronous machine has been carried out. The diode exciters of a brushless synchronous generator with a power of 250 kW with the number of pole pairs p = 2 based on a three-phase bridge rectifier and an auxiliary electric machine of a synchronous type with different numbers of pole pairs are compared. At the first stage, a preliminary electromagnetic calculation of the auxiliary electric machine is performed, taking into account the initial value of the relative magnitude of the resulting electromotive force, the allowable values of inductions in all sections of the magnetic circuit in in forced mode, the length of the magnetic circuit and the rotor winding support are determined. According to the results of the calculation of the rectifier model in the quasi-steel mode of operation, the relative value of the resulting electromotive force of the auxiliary electric machine is specified. At the first stage, a preliminary electromagnetic calculation of the auxiliary electric machine is performed, taking into account the initial value of the relative magnitude of the resulting electromotive force, the allowable values of inductions in all sections of the magnetic circuit in in forced mode, the length of the magnetic circuit and the rotor winding support are determined. According to the results of the calculation of the rectifier model in the quasi-steel mode of operation, the relative value of the resulting electromotive force of the auxiliary electric machine is specified pB = 4.

In the last few years, increasing attention has been given to obtaining reliable results in system identification as a key step in performing model updating, damage detection and structural health monitoring. Many methods have been developed to measure the uncertainty in modal estimates. Some techniques are based on signal resampling to obtain a larger sample space and consequently better process statistics. Thus, this study proposes a new method to quantify uncertainties using the stochastic subspace identification (SSI) technique combined with bootstrap resampling. To validate and compare the performance of the proposed algorithm, two algorithms previously mentioned in the literature were implemented. The first is based on the “moving block method”, and the second is based on blocks of the projection matrix. The proposed method initially generates random decrement functions from signal segments and later uses these functions as bootstrap resampling blocks in SSI. To validate and compare the performance of the proposed algorithm, numerical simulations and two experimental analyses are performed. The first analysis involves a simply supported steel beam subjected to vibration tests through random impacts, and the second involves a three-dimensional four-story frame subjected to vibrations from random signals generated by an electrodynamic exciter. The results of the proposed technique were more robust and accurate than those of the other methods.

Drag type Savonius Vertical Axis Wind Turbine (VAWT) has the advantages of the low total cost, simple manufacture and maintenance. Although the efficiency is low, it is suitable for residential areas with low wind speed. This article intends to use flow control methods to improve the efficiency of Savonius VAWT. Plasma excitation flow control is a relatively new type of active flow control technology. Therefore, this article uses the User-Defined Function (UDF) in ANSYS Fluent to load the plasma excitation sources on the Savonius VAWT blades. This paper numerically studies the influence of plasma flow control on the aerodynamic performance of a two-blade Savonius VAWT. Firstly, the changes in wind turbine performance under different excitation parameters are analyzed. The research results show that adding plasma exciter at a reasonable position can effectively improve the performance of the wind turbine, and the electric field force distribution in different directions will effect its range of action. Meanwhile, the voltage excitation frequency is also an influencing factor. Secondly, the principle and process of plasma excitation on the Savonius VAWT are analyzed. Finally, the relationship between the power consumed by the plasma and the increased power to drive the wind turbine is analyzed. Besides, the influence of plasma excitation on the overall performance of the wind turbine is summarized.