Summary of the pilot phase operation test of Beijing-Tianjin-Tangshan Power Grid

Experimental Research * Beijing-Tianjin-Tang Power Grid Generator Phase-In Operation Test Summary North China Electric Power Research Institute Co., Ltd. (Beijing 100045) Lu Mingxing's test of foolishness was a time when the No. 6 power generation of the Douhe Power Plant was equipped with an automatic dynamic voltage regulator. Into the phase transport to reach the netbookmark1 network power plants must conduct phase-in operation test to determine the ability of each power plant generator set to phase operation, if necessary, according to the grid operation needs to implement generator phase-in operation. The factors affecting the phase-in operation of the generator are analyzed. The phase-in operation test of more than 20 generators in the Beijing-Tianjin-Tangshan Power Grid is introduced in detail. The test shows that the generator phase-in operation can effectively improve the reactive power flow distribution of the grid. The voltage has played a significant role in improving the quality of the power supply. : Beijing-Tianjin-Tangshan Power Grid; Generator; Phase-in-Phase Operation Test At present, North China Power Grid has formed a transmission network with 500kV line as the main grid and 220kV line as the backbone, and initially built a modern grid with high voltage and large capacity for long distance transportation. With the construction and development of the power grid, the high-voltage transmission lines and cable lines are added in large quantities, and the capacitance between the lines and the line-to-ground is correspondingly large, which causes the system capacitance current and the capacitive reactive power to be long when the system load is at a low point. Especially in the holidays, midnight time, the excess reactive power generated by the line, so that the voltage on some pivot points in the power system will be too high, so as to approach or exceed the upper limit of the system operating voltage, seriously affecting the delivery The safe operation of substation equipment and user equipment. In general, a shunt reactor or a synchronous camera can be used to absorb the remaining reactive power, but the equipment investment is added, and there are certain limitations in operation and use. From the perspective of economic operation, the generator is used (especially Large-capacity turbo generators are a practical method for phase-in operation during system downtime. No additional equipment investment is required. Just change the generator excitation operating conditions so that the generator absorbs active power while absorbing. The remaining reactive power of the system can achieve the purpose of balancing the reactive power of the system and adjusting the system voltage. The social and economic benefits are very remarkable. Our institute started the generator into the phase machine as early as the 1980s (Harbin Electric Machinery Factory 200MW) The unit and the No. 2 generator of Datong No. 2 Power Plant (200MW unit of Dongfang Motor Factory) carried out a comprehensive system phase-in operation test, and obtained complete test data, which provided a scientific basis for the phase-in operation of the same type of unit in the future.

Since 2000, in order to further improve the grid voltage quality, North China Power Group Corporation and North China Electric Power Dispatching Bureau require that all power plants in the network must conduct phase-in operation tests to determine the ability of each plant's generator set to enter phase, if necessary, based on The operation of the grid requires the implementation of the phased operation of the generator. According to the requirements of the network bureau, with the cooperation of the relevant personnel of various power plants, our hospital has conducted phase-in operation tests on nearly 30 generators of 17 power plants in North China Power Grid, and obtained a large number of test data to determine these. The limiting factors of the phase-in operation of the generator and the range of the phase-in operation are important for the implementation of the phase-in operation of the North China Power Grid to ensure the voltage quality of the grid. 1 Factors affecting the phase-in operation of the generator. The main problems are 3 points: one is the static stability of the generator; the other is the stator heating caused by the leakage of the generator end; the third is the voltage drop of the generator terminal, which causes the voltage of the busbar to be reduced. The following is a brief discussion on the static stability of these three problems. The theory of motor reduction shows that the static stability of the generator is reduced when it enters the phase. As the excitation current of the generator decreases, the degree of phase advancement increases, and the power angle gradually increases. When the power angle reaches approximately 90*, the generator will reach its static stability limit. If the excitation current is reduced again, Then the generator will lose stability. In fact, when the generator enters phase, the safety limit determined by static stability is also related to the presence or absence of an automatic voltage regulator. When the generator is equipped with an automatic voltage regulator, its stability is greatly improved. The theoretical stability limit will be higher than 90*. As shown in the test, we found in the Douhe Power Plant and the Datong No. 2 Power Plant that when the automatic voltage regulator is not installed, the generator should not keep static stability, and the power angle S can be maximized. Up to 85*12 stator end heating problem When the generator changes from the late phase operation to the phase-in operation mode, the end-synthesis leakage magnetic density value is correspondingly high, causing the end part of the stator core, the pressing ring, the pressure finger and other end structural members. The induced eddy current is large, and additional heat is generated. When the local cooling is insufficient, the temperature is too high, and even exceeds the generator temperature limit value. In other words, the heating problem at the end of the generator stator is another major limiting factor in the depth of phase advancement. For the early generation of the generator for synthesizing the leakage flux with the power factor coh, the end structure of the generator is relatively simple, and there is no measure to reduce the end magnetic density and enhance the cooling. Therefore, when the generator is in phase operation At the end of the temperature rises more, even exceeds the allowable temperature limit of the generator, limiting the phase-in operation of the generator. Especially for the dual-water internal cooling generator, this contradiction is more prominent because the iron core is cooled by air and the cooling effect is poor.

In the recent manufacture of large-scale steam turbine generators, the manufacturer has fully considered some factors affecting the phase-in operation of the generator during the design and manufacture, especially in the case of end-core heating, in the case of structures such as non-magnetic materials. The stator pressure ring and the pressure finger and the end portion of the stator core are designed in a stepped shape, and the narrow groove is formed in the middle, and the copper shielding structure is formed by pressing, which is an effective measure for reducing the strength of the leakage magnetic field at the end, and is cooled at the same time. In the system, the cooling of the ends is enhanced. Many recently produced generators have been installed with temperature measuring points at the end of the factory, so that the technical requirements for temperature motor monitoring of the end core during operation are specified in Article 5.13: "Generator with rated load phase The operating range is designed according to coh for the advanced Q95. Therefore, the generators produced in the near future have certain phase-in operation capability. Generally, there are clear regulations in the factory manual. For example: Harbin Motor Factory regulations: QFSN-300-2 steam turbine power generation The machine can continuously and continuously run the generator with the rated active power load (300MW) power factor csh= 0.95 (advanced) in addition to the water-hydrogen-hydrogen cooling type generator, some other cooling mode generators, such as: double Water cooling, pure hydrogen cooling (such as: MB-J type, 330MW, produced by Mitsubishi Corporation of Japan), air cooling mode (such as: SWX23Z-109LL type, 200MW, produced by ABB), etc., are used to effectively reduce the end temperature. The measures have a certain phase-in operation capability. 1.3 The bus voltage reduction of the plant is currently reduced. At present, the primary wiring mode of a large steam turbine generator set is generally a unit type, that is, the generator exits through the main At the same time that the transformer is boosted and merged into the grid, the outlet also comes with a high-voltage factory transformer. According to 5%, when the generator enters the phase, as the generator excitation current decreases, the generator absorbs the reactive power, which will make The generator outlet voltage drops and causes the factory bus voltage to drop. Sometimes it will be lower than the minimum limit of the factory bus voltage. There are several ways to solve this problem: First, reduce the depth of the generator's phase-in operation to meet the plant. The requirement of electricity consumption; the second is that if the transformer used in the factory is on-load voltage regulation type, the position of the tap changer of the factory transformer can be changed; the third is that the power consumption of the plant will be reversed to the standby transformer. The flexibility and reliability of the system have a certain impact, so it is not advisable to use 2 Beijing-Tianjin-Tangshan power grid generator phase test to improve the situation, take more measures to reduce the end heat. Accurate rei this country / M standard plus bookmark2 synchronous generator phase-in operation, both theory and practice have proved feasible, but due to the type, structure, cooling mode and capacity of the generator, the power plant The gas main wiring is different, how much active power is allowed to be delivered and how much reactive power is absorbed. In theory (1999 edition), the provisions of Article 4.3.5 of the “Code of Operation of Turbine Generators” stipulates: “The phase operation of the generator shall comply with the manufacture. Factory regulations.

When the manufacturer has no regulations, it should be determined by experiment. "2.1 Test method Since 2000, our hospital has carried out the phase advance operation test of nearly 30 units of 17 power plants in North China Power Grid. The purpose of the test is mainly to determine the difference. Under the operating conditions of the generator, the limiting factors of the generator's phase-in operation, and the ability of these generators to absorb the reactive power of the system, and the voltage-regulating effect on the bus voltage.

According to the specific conditions of the generators of each plant, the test method of the phase-in operation of the generator is roughly divided into the following two types: For the early-made generator, the manufacturer has no requirements for the phase-in operation of the generator, and fails to provide the operation output chart. The generator set, or although the manufacturer provides a running force diagram, but the generator set whose boundary is the end temperature limit curve is not clearly stated in the figure, since it is necessary to examine the heat generation of these generator ends, it must be at the stator end. The temperature measuring components are installed on the iron core and the pressure ring and the pressure finger to determine whether the temperature rise at the end is the limiting factor for the phase operation in the test, such as: No. 1 machine of Takai Power Plant (TB2-100-2 type), lower garden Power Plant No. 2 (SQF-100-2 type), Luanhe Power Plant No. 6 (QFN2-100-2 type) Beijing No. 2 Thermal Power Plant No. 4 (QFS-60-2 type) Panshan Power Plant No. 1 temperature measuring component Generally, the copper table copper thermocouple is made according to the structure of the end structure of the generator. Generally, the temperature measuring component is installed during the overhaul of the unit in the position of the end side core, the step tooth pressure finger, the inner circle of the pressure ring, and the thermocouple. Must be firmly bonded, During the test, the temperature value is measured by the thermocouple tour detector. After the test is completed, the thermocouple should be removed from the inside of the generator during the inspection. In 1996, the phase advance operation of the generator has been clearly defined. Therefore, in recent years, When designing and manufacturing generators, the manufacturer has considered some special factors that affect the phase-in operation of the generators, especially the case of end-core heat generation, and adopted various measures to reduce end-heat generation in domestic or imported generators. The manufacturer's factory technical manual has clear regulations for the phase-in operation and provides the generator PQ operation diagram, and temperature-measuring components are embedded in the iron core end and the pressure ring and pressure finger of the generator to facilitate monitoring during operation. The heat of the end core and the structural member should be tested to determine the extent of its phase ingress. This is because the operating diagram provided by the manufacturer only considers the factors of the generator itself, that is, the static stability and the local heating of the stator end or the boundary determined by the two, but the factory voltage reduction can be determined through experiments. In addition, the ability of the generator to absorb the reactive power of the system and the voltage regulation effect on the system bus voltage are determined through experiments. For the forward-running tests of these generators, the end temperature measurement may not be performed, but based on the operating limit diagrams provided by each manufacturer. This type of unit includes: domestically produced QFQS-200-2, QFSN-200-2, QFSN-300-2, QFS-100-2 and some imported units 22 test results analysis according to our 20 The phase-in operation test of multiple generators (Table 1 shows the results of several typical generator phase-in operation tests in the Beijing-Tianjin-Tangshan grid) can analyze the following results.

22.1 Excitation Regulator All generator phase-in operation tests are carried out directly with an automatic excitation regulator. There is no phase-in operation test for exiting the automatic excitation regulator. 22.2 The generator power angle is theoretically and practically proven. After the generator is equipped with an automatic excitation regulator, its static stability limit power angle can exceed 90*. However, from the perspective of static stability reserve and safety, even with an automatic excitation regulator, the power angle should be less than 90*. As a control strip, when the characteristics of the automatic excitation regulator are poor or malfunction when operating in the range of W<90*, it does not directly cause the generator to lose stability. Therefore, based on the above considerations, a certain static and stable reserve margin is set aside. Usually, the limit value of the power angle is set to 70*. In the test, only the generators of individual power plants have a power angle of 70* at high load. Conditions, such as: Xiahuayuan Power Plant No. 2, Jingneng Thermal Power Co., Ltd. No. 2, most other units are subject to their other restrictions. First, the generator's phase-in operation is limited, so the power angle is less than 70*. The phase stability of the generator and the static stability of the generator can be guaranteed.

22.3 Generator end heating In addition to individual units, generator end heating is not the primary limiting condition for phase ingress.

Only the stator end iron core of No. 4 (QFS-60-2) and No. 1 (TB2-100-2) of Beijing No. 2 Thermal Power Plant became the limiting conditions for the phase-in operation of the generator. The No. 4 machine was factory-made in 1975, and the cooling method was double-water internal cooling. When the load was 30~47MW, the power generation of the 侩 蚺 不用 安 安 安 1 1 old old old old old old old old old old old old old old old old old The results of the phase-in operation test results of several typical generators. The result of the phase-in-phase test. The name of the generator (advance). The voltage of the busbar is reduced by %. The high-voltage power plant (hysteresis) end of the iron core heating No. 1 (formerly manufactured in the Soviet Union) Jingfeng Thermal Power ( Three heat) No. 7 machine (manufactured by Beizhong Motor Factory), No. 6 machine (made by Harbin Electric Machinery Factory), Power Station, Qinhuangdao Power Plant, No. 4 (made by Shanghai Electric Machinery Factory), electric stator voltage, low port power plant The No. 4 machine (manufactured by Ansaldo, Italy) uses the No. 1 unit of the Sanhe Power Plant (manufactured by Mitsubishi Corporation of Japan) to use the electric power plant No. 1 (made in Russia) of the electric power plant, and there is a c\9 group. The remaining part of the transformer for the whole high pressure plant The end cooling effect is poor, so when the active load is 100MW and 85MW, the power factor cosh is 0.99 (hysteresis) and 1.00, respectively, and the end temperature is close to the limit value, so phase advance operation is not allowed; when the active load is 45MW When the phase can be run to the power factor cosh=For other units that have been tested before the test, the temperature rise test is carried out, such as: Xiahua Power Plant No. 2 Jihe Power Plant No. 6 and Panshan Power Plant 1 No. The temperature of the end of these generators is not high, and it does not become the limiting condition for the phase-in operation. 22.4 Bus voltage of the factory. In this test, in principle, the generators are directly tested by the factory branch, only In some cases, the phase difference test of the power plant with the factory power supply and the power consumption of the factory is used. For most generator sets, when the bus voltage of the factory is reduced, the voltage of the bus bar is reduced when the phase is running. The phase-in operation depth of the generator. Although it is possible to increase the bus voltage of the plant by adjusting the split of the high plant, in fact, most of the power plants in the late phase operation of the generator (power factor cosh is 0.90 lag), the factory bus voltage has approached or exceeded the factory bus voltage. The rated value is 1.05 times (that is, it reaches 6.3~6.4kV). For example, the data of No. 1 generator of Jingneng Thermal Power Co., Ltd. in the case of late phase operation 2 Jingneng Thermal Power Co., Ltd. No. 1 generator operation data generator is active /MW generator reactive power / Mvar power factor (hysteresis) generator stator voltage / kV factory bus voltage Under the above circumstances, if the plant bus voltage is increased, it will adversely affect the plant system, therefore, most power plants There is a small amount of margin, which can adjust the split position of the high plant change when necessary, improve the bus voltage of the plant, and enable the generator to improve the ability to enter the phase. 22.5 Power factor cosh limit according to the North China Electric Power Dispatching Bureau The requirements for the phase-in operation of the generators in the network should reach cosh = 0.95 (advanced). Therefore, most power plants basically only achieve the power factor cosh = 0.95 in the phase-in phase test. Up to the first time, a total of 13 units have a limit condition of cosh=0.95 (advanced) at low load. At this time, other restrictions (power angle 70* end bus heater bus voltage, etc.) have not yet worked, if they can be properly relaxed When the load factor is limited by the power factor, such as csh=0.90 (advance), the phase-in operation capability of these generators can be further improved. 22.6 Bus voltage reduction. From the phase-in-phase test data of 27 generators, the generator phase The voltage regulation effect on the bus voltage during operation is obvious. Generally, the bus voltage can be reduced by 1%~2%, and the maximum can reach 5.8%. Among them, Panshan Power Plant No. 1 (average reduction of 12.5%) Dagang Power Plant No. 4 Machine (average reduction of 5.3kV, 23%) Luanhe Power Plant No. 6 (average reduction of 5. 5.3%) Qinhuangdao Power Plant No. 4 (average reduction of 63kV, 29%) Sanhe Power Plant No. 1 (average reduction of 4.7kV, 21%) The voltage regulation effect is obvious. When the generators of other power plants are in phase operation, the bus voltage can be reduced by 1.1~4.0kV on average. There is a certain voltage regulation effect. It can be seen that after the generator enters phase, although it is used by the factory. Limitation of conditions such as bus voltage, The ability of the generator to absorb the reactive power of the system is limited, but it can play an obvious role in improving the voltage distribution of the reactive power flow of the power grid and improving the power quality. 3 Conclusion In order to ensure the static stability of the generator during the phase-in operation of the generator Sex, the generator must be equipped with automatic voltage regulator. More than 20 generators in the Beijing-Tianjin-Tangshan grid have entered the phase-in operation test. The main limiting conditions for the phase-in operation of generators of 200MW and above are the factory bus voltage, and most of the power plants are rated at the same time. Under the premise of normal operation and phase-in operation, there is no room for adjusting the high-factor change head. The generator phase-in operation can effectively improve the reactive power flow distribution of the power grid and adjust the system voltage, which can obviously improve the power supply quality. Up to page 6) Wall, data encryption and decryption, digital signature and digital certificate technology, so that the system has strong information security. The data network should use a dedicated network as much as possible to meet the requirements of security and real-time reliability. Comprehensive consideration of the construction of the technical support system for the power market in North China Power Grid should be fully designed for the power market technical support system of North China Power Grid. Consider the interdependencies and integration of various components, such as the interdependencies of servers, network devices, network management devices, database systems, and application systems, and fully consider the scalability and compatibility of these devices and systems; the development of application modules must Focus on independence, scalability, and replaceability; application interfaces must comply with relevant standards, focusing on comprehensiveness, scalability, and security.

The construction of the technical support system for the power market in North China Power Grid should have the ability to interconnect with other grid power market technical support systems, adapt to the needs of future regional and national power market power transactions, and adapt to the power market opened by the power generation side to the power distribution side. The need for the transition of the power market 3 Conclusion The power market operation simulation system of North China Power Grid can be used not only to train North China Power Grid, provincial dispatchers and traders, but also to conduct feasibility studies on the technical support system of the North China Power Grid power market, and to demonstrate the power of North China Power Grid. The rationality of market operation rules, assisting decision-making and analyzing the problems related to power market operation, is of great significance for the establishment of scientific and effective power market in North China Power Grid. The promotion and application of power market operation simulation system of North China Power Grid requires North China Power Group Corporation and provincial companies. The coordination of planning, planning, finance, and scientific research departments can complete the power market interface of the Beijing-Tianjin-Tangshan grid economic dispatching program. This work should be carried out as soon as possible on the basis of the existing energy management system (EMS). Make full use of the internal resources of the enterprise to transform scientific and technological achievements into productivity, improve the operation level of the power market in North China Power Grid, and ensure the safety, stability, quality and economic operation quality of North China Power Grid is the lifeline of the enterprise.

CPVC Resin

CPVC resin is made by chlorination modification of PVC resin and is one advanced engineering material. This product is white or canary loose grain or powder with no smell, odorless and innocuity. After chlorination, the irregularity of molecular bond of the PVC resin and the polarity of molecular chain increase, the dissolvability and chemical stability of the resin also increase, and accordingly improve the heat resistance and resist the corrosion of acid, caustic, salt and oxidant etc. In addition, it improve the mechanical performance of numerical heat distortion temperature and chlorine content increases from 56.7% to 63-69% and Vicat softening temperature from 72-82 ℃ to 90-125 ℃ ; its highest service temperature can reach 110 ℃ and long-term service temperature can reach 95 ℃ . Accordingly, CPVC is one kind of advanced engineering plastic with vast foreground.

CPVC Resin,CPVC Resin for Pipes,CPVC Resin CAS 68648-82-8,CPVC Resin for Fittings,CPVC Resin for Industrial

Shandong Novista Chemicals Co.,Ltd (Novista Group) , https://www.novistachem.com