Auxiliary Power Equipment Research Articles

Technical Diagnostics and Adjustment of Steam Turbine Units

The main activities conducted at the department for technical diagnostics and repair technologies of the All-Russia Thermal Engineering Institute (JSC “VTI”) are described. It is shown that the diagnostics of the main and auxiliary power equipment can be efficiently performed using specialized monitoring tools. Effective methods and tools for assembling rotor couplings of turbine units are presented. Technologies for repairing the blade apparatus of steam turbines arereviewed.

MATHEMATICAL MODEL OF OVERHEAD PARAMETRIC EDDY CURRENT PRIMARY MEASURING TRANSDUCER OF ABSOLUTE MOVEMENT

To date, even in the developed countries of Europe, more than 50% of the power generating equipment of hydropower plants have worked their design life. In the CIS countries, the percentage of such equipment is even higher. The complete replacement of such equipment requires a large amount of investment, while a significant part of the latter has a satisfactory technical condition for the further extension of the service life. However, with an increase in the operating time of every electrical equipments, the probability of its failure inevitably increases, which can lead to significant material losses and to a significant danger to the life and health of the power plant personnel. Therefore, in view of the foregoing, monitoring and early diagnosis systems, which are entrusted with the protection function of both hydraulic turbines and auxiliary power equipment, are becoming increasingly relevant. One of the most promising methods of technical control and diagnostics of hydraulic units is the analysis of their vibro-acoustic characteristics. Including the axial component. However, a significant technical problem that arises in the construction of such systems is the limited use of known absolute vibration displacement sensors due to the lack of their high-precision mathematical models. In the article a mathematical model of an overhead parametric eddy current primary measuring transducer of absolute displacement has been developed. It is shown that both the effective value of the output current and the shift of its initial phase are found to be functionally dependent on the distance between the sensor and the conductive medium with a stable supply voltage. It has been established that, while ensuring acceptable overall dimensions, this sensor has sufficient sensitivity to convert the displacement to the effective (amplitude) value of the output current, which is constant in the range of movement from 0 to 5 mm, to ensure the required measurement accuracy.

Mathematical model of capacitance micromechanical accelerometer in static and dynamic operating modes

Monitoring and early diagnosis systems, on which the protection function of both hydroturbines and auxiliary power equipment rely, are becoming increasingly relevant. One of the most promising methods of technical control and diagnostics of hydo units is the analysis of their vibro-acoustic characteristics. But a significant technical problem that arises in the construction of such systems is the limited use of known sensors of vibration velocity and vibration displacement due to the fact that the rotary speed of hydro units is usually below the lower limit of operation of sensors of this type. One of the promising ways to solve this problem is using capacitive micromechanical accelerometers. However, the existing mathematical models describing this type of accelerometers have low accuracy, which limits their practical using. The mathematical models of the capacitive micromechanical accelerometer for static and dynamic modes of operation are developed in this article. It was established that this accelerometer has a constant sensitivity, therefore its static characteristic is linear. It is shown that in the dynamic mode of operation of a capacitive micromechanical accelerometer has a dynamic error component, the cause of which is its own displacement of the moving part of the sensor, which is due to the inertial properties of the moving part and elastic properties of stretch marks. The mathematical dependence of the absolute dynamic error of the capacitive micromechanical accelerometer is obtained, the removal of which from the measurement results will improve the accuracy of the specified primary measuring transducer.

Emissions of Airport Monitoring with Solar Occultation Flux-Fourier Transform Infrared Spectrometer

Both domestic and international aviation industries have experienced a boom, which results in a dramatic increase in emissions of the aviation industry in recent decades. Therefore, domestic and abroad scientists adopted different methods to measure emissions; however, there are no appropriate methods to measure the emissions of the whole airport. In order to provide data support for the relevant departments to take appropriate emission reduction measures, solar occultation flux-Fourier transform infrared spectrometer (SOF-FT-IR) is used to monitor the emissions of Beijing Capital International Airport. CO, CO2, C2H4, and CH2O are selected as the target gases and are quantitatively analyzed with the nonlinear least squares method to get the column concentration. Then, the flux can also be calculated by linking the wind velocity and direction with the column concentration. A comparison between the results measured by SOF-FT-IR and the results measured by the method published by the Intergovernmental Panel on Climate Change (IPCC) indicates that auxiliary power equipment and ground support equipment for the emission of the airport are also important emission sources besides the aircraft and the concentration distribution gives powerful and useful pieces of evidence to locate the emission sources. In order to decrease the contribution of the airport to the air pollution, the key point is to reduce the emissions of the APU and mobiles in the airport.

A novel prediction method of vibration and acoustic radiation for rectangular plate with particle dampers

Particle damping technology is widely used in mechanical and structural systems or civil engineering to reduce vibration and suppress noise as a result of its high efficiency, simplicity and easy implementation, low cost, and energy-saving characteristic without the need for any auxiliary power equipment. Research on particle damping theory has focused on the vibration response of the particle damping structure, but the acoustic radiation of the particle damping structure is rarely investigated. Therefore, a feasible modeling method to predict the vibration response and acoustic radiation of the particle damping structure is desirable to satisfy the actual requirements in industrial practice. In this paper, a novel simulation method based on multiphase flow theory of gas particle by COMSOL multiphysics is developed to study the vibration and acoustic radiation characteristics of a cantilever rectangular plate with Particle dampers (PDs). The frequency response functions and scattered far-field sound pressure level of the plate without and with PDs under forced vibration are predicted, and the predictions agree well with the experimental results. Results demonstrate that the added PDs have a significant effect on vibration damping and noise reduction for the primary structure. The presented work in this paper shows that the theoretical work is valid, which can provide important theoretical guidance for low-noise optimization design of particle damping structure. This model also has an important reference value for the noise control of this kind of structure.

Control of CO2 emission through enhancing energy efficiency of auxiliary power equipment in thermal power plant

This paper describes the results of energy efficiency enhancement in 23 numbers of 210MW coal fired power plants spread over India. Energy efficiency improvement of major auxiliary equipment with different plant load factors are summarized here with improved performance. The effect of plant load factor on all major auxiliary equipment and improvement in performance of auxiliary equipment are discussed in this paper. Operation of the plant at improved plant load factor reduced the specific auxiliary power from 11.23% at 70% PLF to 8.74% at 100% PLF that reduced the net auxiliary power by 9.1MU/year that is an equivalent reduction of CO2 emission by 9500t/year. Optimizing the excess air, controlling the furnace ingress, enhanced energy efficiency of individual equipment by proper maintenance, etc., improves the plant capacity and reduces the overall auxiliary power by about 1.5–2.1% of gross energy generation i.e., equivalent CO2 reduction of 23,000–32,400t/year and release an additional power of about 3.5MW (for a typical one 210MW power plant) into grid.

8200호대 전기기관차 객차전원공급장치(HEP)의 출력전압품질향상을 위한 최적화된 PWM 방법

HEP(Head Electric Power) system, supplying 3-phase service power to the coach vehicles, is a kind of special auxiliary power equipment which is boarded on 8200 series electric locomotives in KORAIL. This equipment shares high voltage DC link with a main propulsion converter/inverter systems. It was difficult to use high frequency PWM technique so that GTO has been used as a power device same like the main power system. Due to low PWM frequency(300㎐) of HEP inverter, the output voltage has less power quality comparing to normal SIV(Static Inverter) system. In this paper, an optimal PWM strategy is presented for new IGBT type HEP inverter system. Several PWM techniques were investigated to improve output voltage quality under fixed lower filter inductance and not high PWM frequency. Finally PC simulations have been done to clarify its availability.

EHV Series Capacitor Banks. A New Approach to Platform to Ground Signalling, Relay Protection and Supervision

Series capacitor banks for transmission systems above 145 kV, are normally erected for technical and economical reasons on fully insulated platforms per phase. Several methods have been used to realize the relay protection for series capacitor banks erected on platforms. One of the first designs used in the 1950's utilized protection relays and auxiliary power equipment on the insulated platforms. Signal communication was carried out by mechanical contact devices, which transmitted on/off signals from platform level to ground. In the late 1960's, the mechanical contact devices were replaced by fibre optics. The protection relays, together with electronic equipment and auxiliary power equipment, were still located on the insulated platforms. However, to give the relay protection of series capacitors the same simplicity as for ordinary substations, a new concept was introduced in the early 1970's. A number of signals were transmitted between EHV potential and ground via a modified current transformer. The relay protection and control equipment was located in the control room. The new Protection and Supervision system includes the advantages and excludes the disadvantages of the foregoing systems. The new system comprises optical current transformers, and a microprocessor-based protection, supervision and control system, located in the control room. Optical fibres connect the current transducers on the platform with the equipment in the control room. Auxiliary power to the current transducers is transmitted by light from ground level.

Terminal and Main Station Functions

There are three types of main stations associated with the L5 system. Power feed main stations provide the dc power required by the line repeaters. Switching power feed main stations add the automatic line protection switching equipment for the L5 system. Terminal main stations provide the equipment for multiplex and related functions. This equipment includes the jumbogroup multiplex (JMX), which translates arrays of six analog or digitally derived mastergroup signals to and from line frequency; the L5 line bay, which provides the interface between the L5 line and the terminal equipment, including branching and blocking circuitry; the jumbogroup frequency supply, which provides highly stable signals from which JMX carriers are derived; the basic jumbogroup trunk bay, which processes the JMX baseband signal; and the transmission surveillance system which, in conjunction with the E2 status reporting and control system, allows the remote monitoring and trouble shooting of L5 line and main station equipment. L5 is a hardened system with main stations housed in self-contained, underground buildings. These buildings provide life support and auxiliary power equipment which allow main stations to operate under emergency status for as long as several weeks.

A Purse Seine for Sampling Juvenile Salmonids

to collect live juvenile salmonids in the $5, 000. limnetic zone in numbers sufficient for assessing migratory behavior. The need Description of Equipment for this sampling equipment arose after conventional floating traps—used successPurse Seine fully along the shorelines of the upper and middle reservoir—failed to take fish in The purse seine, 600 feet long by 35 quantity at the lower end of the impoundfeet deep (600 meshes from floatline to ment. Samples also were required from leadline), was constructed principally of offshore areas of the 57.5-mile-long im3/8-inch (bar measure) knotted nylon webpoundment. Trawling was attempted, but bing (thread size, 210-6). To reduce cost, catches were small and fish were often in the lower 10 feet was made of a cheaper poor condition for marking or tagging. synthetic material of the same mesh size. Unsatisfactory results with trawls led to The bunt end of the seine (figure 1) was consideration of the purse seining techmade of 1/4-inch (bar measure) knotiess pique, nylon to retain salmonids as short as Purse seines. are commonly used for 50 millimeters. Sponge): floats, spaced commercial harvesting of marine food fish 15 inches apart on a floatline, supported and have been described and. illustrated the net in water. About 20 percent hang-in by Knake (1950), McNeely (1961), and was made along the floatline and leadline. Dumont and Sundstrom (1961). Craddock' Purse rings, spaced 18 feet apart, were explored the possibility of using a cornsuspended on polypropylene dropper lines mercial bait seine to capture fingerling from the leadline. The purse line consockeye salmon (Oncorhynchus nerka). A sisted of two 325-foot lengths of 1 / 2-thch barge and a small skiff were used, but the nylon rope joined by a 1/4-inch figures attempt was unsuccessful, largely because eight clamp to permit a quick removal. of the lack of auxiliary power equipment from the rings after a set had been cornfor handling the seine. Based in part pleted. on Craddock's experience, a lightweight, small-mesh model of a commercial purse Depressor Weight

Modern railway passenger car auxiliary power equipment

Immediately after the close of World War II, the railroads began to order a large number of passenger cars in an effort to retain part of the passenger business that had come to them during the war years. As might have been expected, a large number of different ideas were given a quick try-out and adopted by different railroads. Many of these ideas had as their basis a very large increase in the amount of power which would be required for electric devices on the cars.

Modern Railway Passenger-Car Auxiliary-Power Equipment

Immediately after the close of World War II, the railroads began to order a large number of passenger cars in an effort to retain part of the passenger business that had come to them during the war years. As might have been expected, a large number of different ideas were given a quick try-out and adopted by different railroads. Many of these ideas had as their basis a very large increase in the amount of power which would be required for electric devices on the cars.