GB 50052-1995 Design specification for power supply and distribution systems
Some standard content:
Engineering Construction Standard Full Text Information System
National Standard of the People's Republic of China
GB50052-95
Code for design of electric power supply systems
Code for design of electric power supply systemsConstruction Standard
1995-07-12Release
1996-05-01
State Bureau of Technical Supervision
Ministry of Construction of the People's Republic of China
Engineering Construction Standard Full Text Information System
Jointly Released
Engineering Construction Standard Full Text Information System
National Standard of the People's Republic of China
Code for design of electric power supply systems systemsGB50052—95
Editor department: Ministry of Machinery Industry of the People's Republic of ChinaApproval department: Ministry of Construction of the People's Republic of ChinaEffective date: May 1, 1996
Engineering construction standard full text information system
Engineering construction standard full text information system
Notice on the release of the national standard "Design Specifications for Power Supply and Distribution Systems"bzxz.net
Jianbiao [1995] No. 324
According to the requirements of the State Planning Commission's document [1986] No. 250, the "Design Specifications for Power Supply and Distribution Systems" jointly revised by the former Ministry of Machinery and Electronics Industry and relevant departments has been reviewed by relevant departments. The "Design Specifications for Power Supply and Distribution Systems" GB50052-95 is now approved as a mandatory national standard and will be implemented from May 1, 1996. The former national standard "Design Specifications for Industrial and Civil Power Supply Systems" GBJ52-83 will be abolished at the same time. The Ministry of Machinery Industry is responsible for the management of this specification, and the Second Design Institute of the Ministry of Machinery Industry is responsible for its specific interpretation and other work, and the Ministry of Construction's Standards and Norms Institute is responsible for its publication and distribution.
Ministry of Construction of the People's Republic of China
July 12, 1995
Engineering Construction Standards Full-text Information System
Engineering Construction Standards Full-text Information System
Revision Notes
This specification is edited by the Ministry of Machinery Industry in accordance with the notification requirements of the State Planning Commission's [1986] No. 250 document, and is specifically revised by the Second Design Institute of the Ministry of Machinery Industry in conjunction with relevant units from the "Industrial and Civil Power Supply System Design Specification" GBJ52-83.
During the revision process, the specification group conducted extensive investigations and studies, carefully summarized the experience since the implementation of the specification, absorbed some scientific research results, and widely solicited opinions from relevant units across the country. Finally, our ministry and relevant departments reviewed and finalized it. The main contents of this revision are: adding particularly important loads and their power supply requirements in the load classification; in the content of ensuring power quality, new measures are formulated to limit voltage fluctuations and flickers, control the distortion rate of the sinusoidal waveform of the power grid voltage caused by harmonics, and reduce the asymmetry of the three-phase low-voltage distribution system; it is also proposed that the on-load voltage regulation of the power grid above 35kV should be reversed, some reactive loads should be compensated separately on-site, and three-phase distribution transformers with D, yn11 connection groups should be selected. During the implementation of this specification, if it is found that there is a need for modification and supplementation, please send your opinions and relevant materials to the "Power Supply and Distribution System Design Specification" Management Group of the Second Design Institute of the Ministry of Machinery Industry (Address: No. 338 Shiqiao Road, Hangzhou, Postal Code: 310022), and copy it to the Industry Development Department of the Ministry of Machinery Industry for reference in future revisions. Ministry of Machinery Industry
July 1995
Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Chapter 1
Chapter 2
Chapter 3
Chapter 4
Chapter 5
Chapter 6
Appendix 2
Load classification and power supply requirements
Power supply and power supply system
Voltage selection and power quality.|| tt||Reactive power compensation
Low voltage power distribution
Term explanation
Explanation of terms used in this specification
Additional explanation
Engineering construction standard full text information system
Engineering construction standard full text information system
Chapter I General Provisions
Article 1.0.1 This specification is formulated to ensure that the design of power supply and distribution systems implements the national technical and economic policies, ensures personal safety, reliable power supply, advanced technology and economic rationality.
Article 1.0.2
This specification applies to the design of new and expanded power supply and distribution systems of 110kV and below.
Article 1.0.3 The design of power supply and distribution systems must be based on the overall situation, take into account all aspects, and reasonably determine the design plan according to the nature of the load, power consumption capacity, project characteristics and regional power supply conditions.
Article 1.0.4 The design of the power supply and distribution system should be based on the characteristics, scale and development plan of the project, combining the long-term and short-term, with the short-term as the main focus. Article 1.0.5 The design of the power supply and distribution system should adopt electrical products with high efficiency, low energy consumption and advanced performance that meet the current relevant national standards. Article 1.0.6 In addition to complying with this specification, the design of the power supply and distribution system should also comply with the provisions of the current relevant national standards and specifications. Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Chapter 2 Load Classification and Power Supply Requirements
Article 2.0.1 The power load should be classified according to the requirements for power supply reliability and the degree of political and economic losses or impacts caused by power outages, and should comply with the following provisions:
1. When one of the following conditions is met, it should be a first-level load: 1. When power outages will cause personal injury or death. 2. When power outages will cause major political and economic losses. For example: major equipment damage, major product scrapping, large-scale scrapping of products produced with important raw materials, the continuous production process of key enterprises in the national economy is disrupted and takes a long time to recover, etc. 3. The interruption of power supply will affect the normal work of power users with major political and economic significance. For example: important power loads in power users such as important transportation hubs, important communication hubs, important hotels, large sports stadiums, and public places where a large number of people gather frequently for international activities.
In the first-level load, the load that will cause poisoning, explosion and fire when the power supply is interrupted, and the load that is not allowed to interrupt the power supply in particularly important places, should be regarded as particularly important loads.
Second, when one of the following conditions is met, it should be a second-level load: 1. When the interruption of power supply will cause great losses in politics and economy. For example: major equipment damage, a large number of products are scrapped, the continuous production process is disrupted and takes a long time to recover, and key enterprises have a large reduction in production, etc.
2. The interruption of power supply will affect the normal work of important power users. For example: important power loads in power-consuming units such as transportation hubs and communication hubs, and interruption of power supply will cause disorder in important public places with a large number of people, such as large theaters and large shopping malls.
3. Those that do not belong to the first and second level loads should be the third level loads. Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Article 2.0.2 The power supply of the first level load shall comply with the following provisions: 1. The first level load shall be supplied by two power supplies: when one power supply fails, the other power supply shall not be damaged at the same time.
2. In addition to being supplied by two power supplies, the particularly important loads in the first level load shall also be equipped with an emergency power supply, and it is strictly forbidden to connect other loads to the emergency power supply system. Article 2.0.3 The following power supplies can be used as emergency power supplies: 1. Generator sets independent of the normal power supply. 2. Dedicated feeder lines in the power supply network independent of the normal power supply. 3. Storage batteries.
4. Dry batteries.
Article 2.0.4 According to the allowable power interruption time, the following emergency power sources can be selected respectively:
, For power supply with an allowable power interruption time of more than 15s, a fast self-starting generator set can be selected.
2. If the action time of the automatic device can meet the allowable power interruption time, a dedicated feeder line independent of the normal power supply with an automatic input device can be selected. 3. For power supply with an allowable power interruption time of milliseconds, a battery static positive uninterruptible power supply device, a battery mechanical energy storage motor type uninterruptible power supply device or a diesel engine uninterruptible power supply device can be selected.
Article 2.0.5 The working time of the emergency power supply should be considered according to the parking time required by production technology. When used in conjunction with an automatically started generator set, it should not be less than 10 minutes.
Article 2.0.The power supply system of 6 secondary loads should be powered by two lines. When the load is small or the power supply conditions in the area are difficult, the secondary load can be powered by a dedicated overhead line or cable of 6kV or above. When an overhead line is used, it can be powered by one overhead line; when a cable line is used, a line consisting of two cables should be used for power supply, and each cable should be able to withstand 100% of the secondary load. Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Chapter 3 Power Supply and Power Supply System
Article 3.0.1 When one of the following conditions is met, the power user should set up a self-provided power supply:
, when it is necessary to set up a self-provided power supply as an emergency power supply for particularly important loads in the primary load or when the second power supply cannot meet the conditions of the primary load. 2. When it is more economical and reasonable to set up a self-provided power supply than to obtain a second power supply from the power system. 3. When there is stable waste heat, pressure difference, and exhaust gas available for power generation all year round, and the technology is reliable and economical.
4. When the area is remote and far away from the power system, it is economically reasonable to set up a self-provided power supply. Article 3.0.2 Measures must be taken to prevent parallel operation between the emergency power supply and the normal power supply.
Article 3.0.3 The design of the power supply and distribution system, except for the particularly important loads in the primary load, should not be designed based on the fact that one power system is under maintenance or failure while the other power supply fails.
Article 3.0.4 For power users who need two power supply lines, it is advisable to use the same voltage level for power supply. However, according to the different needs of each level of load and the regional power supply conditions, different voltages can also be used for power supply.
Article 3.0.5 When it is difficult for a power user with a primary load to obtain two power supplies from the regional power grid but it is possible to obtain a second power supply from a neighboring unit, it is advisable to obtain a second power supply from the unit.
Article 3.0.6 When one of the two or more power supply and distribution lines that supply power at the same time is interrupted, the remaining lines should be able to meet all primary and secondary loads. Article 3.0.7 The power supply system should be simple and reliable, and the number of transformer and distribution levels of the same voltage power supply system should not be more than two. Article 3.0.8 The high-voltage distribution system should adopt the radial type. According to the capacity, distribution and geographical environment of the transformer, the trunk type or ring type can also be used. Article 3.0.9 According to the capacity and distribution of the load, the distribution substation should be close to the load center. When the distribution voltage is 35kV, a direct reduction to 220/380V distribution voltage can also be used. Article 3.0.10 Low-voltage interconnection lines should be set between adjacent substations within the power user unit. Article 3.0.11 Power users with small loads should be connected to the regional low-voltage power grid. Engineering Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
Chapter 4 Voltage Selection and Power Quality
Article 4.0.1 The power supply voltage of the power user unit shall be determined through technical and economic comparison based on factors such as power consumption capacity, power equipment characteristics, power supply distance, number of power supply line loops, the status of the local public power grid and its development plan. Article 4.0.2 When the power supply voltage is 35kV and above, the first-level distribution voltage of the power user unit shall be 10kV. When the total capacity of 6kV power equipment is large and the selection of 6kV is economically reasonable, 6kV should be used. The low-voltage distribution voltage should be 220/380V. Article 4.0.3 When the power supply voltage is 35kV, it can reduce the number of distribution and transformation levels, simplify the wiring, and is technically and economically reasonable, the distribution voltage should be 35kV. Article 4.0.4 Under normal operation, the allowable value of voltage deviation at the terminals of electrical equipment (expressed as a percentage of rated voltage) should meet the following requirements: 1. Motors: ±5%.
2. Lighting: ±5% in general workplaces; for small-area general workplaces far away from substations, when it is difficult to meet the above requirements, it can be +5%, -10%. Emergency lighting, road lighting and guard lighting are +5%, -10%. 3. Other electrical equipment is ±5% when there are no special regulations. Article 4.0.5 The design of the power supply and distribution system should meet the following requirements to reduce voltage deviation:
1. Correctly select the transformer ratio and voltage tap. 2. Reduce system impedance.
3. Take measures to compensate for reactive power.
4. Make the three-phase load balanced.
Article 4.0.6 When calculating voltage deviation, the voltage regulation effect after taking the following measures shall be taken into account:
1. Automatically or manually adjust the access capacity of parallel compensation capacitors and parallel reactors Engineering 6 Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
2. Automatically or manually adjust the excitation current of the synchronous motor. 3. Change the operation mode of the power supply and distribution system. Article 4.0.7 When the transformer in the substation is in one of the following situations, the on-load voltage regulating transformer shall be used:
1. The step-down transformer in the substation with a voltage of 35kV or above directly supplies power to the 35kV and 10 (6)kV power grids.
2. The main transformer of the 35kV step-down substation, when the voltage deviation cannot meet the requirements.
10(6)kV distribution transformers should not use on-load voltage-changing transformers Article 4.0.8
; however, when the local 10(6)kV power supply voltage deviation cannot meet the requirements, and the power user has equipment with strict voltage requirements, and it is not technically and economically reasonable to set up a voltage-changing device alone, a 10(6)kV on-load voltage-changing transformer can also be used. Article 4.0.9 The voltage deviation should meet the requirements of the voltage at the end of the power equipment, and the on-load voltage regulation of the power grid above 35kV should be implemented in the reverse voltage regulation mode. The range of reverse voltage regulation should be 0 to +5% of the rated voltage.
Article 4.0.10
When the power supply of impact loads needs to reduce the voltage fluctuation and voltage flicker of the power grid caused by impact loads (excluding the voltage drop allowed when the motor starts), the following measures should be taken:
1. Use dedicated power supply lines.
2. When sharing the distribution line with other loads, reduce the impedance of the distribution line. 3. The high-power impact load or impact load group and the load sensitive to voltage fluctuation and flicker shall be powered by different transformers. 4. The furnace transformer of the high-power arc furnace shall be powered by the power grid with larger short-circuit capacity.
Article 4.0.11 To control the distortion rate of the sinusoidal waveform of the power grid voltage caused by the harmonics generated by various nonlinear electrical equipment, the following measures shall be taken: 1. The transformers of various high-power nonlinear electrical equipment shall be powered by the power grid with larger short-circuit capacity.
Engineering Construction Standard Full Text Information SystemArticle 11
Electricity users with small loads should be connected to the regional low-voltage power grid. Engineering Construction Standards Full Text Information System
Engineering Construction Standards Full Text Information System
Chapter 4 Voltage Selection and Power Quality
Article 4.0.1 The power supply voltage of the power user should be determined based on the power capacity, the characteristics of the power equipment, the power supply distance, the number of circuits of the power supply line, the current status of the local public power grid and its development plan, etc., after technical and economic comparison. Article 4.0.2 When the power supply voltage is 35kV and above, the first-level distribution voltage of the power user should be 10kV. When the total capacity of the 6kV power equipment is large and the selection of 6kV is economically reasonable, 6kV should be used. The low-voltage distribution voltage should be 220/380V. Article 4.0.3 When the power supply voltage is 35kV, it can reduce the number of distribution and transformation levels, simplify the wiring, and is technically and economically reasonable, the distribution voltage should be 35kV. Article 4.0.4 Under normal operation, the allowable value of voltage deviation at the terminals of electrical equipment (expressed as a percentage of rated voltage) should meet the following requirements: 1. Motors: ±5%.
2. Lighting: ±5% in general workplaces; for small-area general workplaces far away from substations, when it is difficult to meet the above requirements, it can be +5%, -10%. Emergency lighting, road lighting and guard lighting are +5%, -10%. 3. Other electrical equipment is ±5% when there are no special regulations. Article 4.0.5 The design of the power supply and distribution system should meet the following requirements to reduce voltage deviation:
1. Correctly select the transformer ratio and voltage tap. 2. Reduce system impedance.
3. Take measures to compensate for reactive power.
4. Make the three-phase load balanced.
Article 4.0.6 When calculating voltage deviation, the voltage regulation effect after taking the following measures shall be taken into account:
1. Automatically or manually adjust the access capacity of parallel compensation capacitors and parallel reactors Engineering 6 Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
2. Automatically or manually adjust the excitation current of the synchronous motor. 3. Change the operation mode of the power supply and distribution system. Article 4.0.7 When the transformer in the substation is in one of the following situations, the on-load voltage regulating transformer shall be used:
1. The step-down transformer in the substation with a voltage of 35kV or above directly supplies power to the 35kV and 10 (6)kV power grids.
2. The main transformer of the 35kV step-down substation, when the voltage deviation cannot meet the requirements.
10(6)kV distribution transformers should not use on-load voltage-changing transformers Article 4.0.8
; however, when the local 10(6)kV power supply voltage deviation cannot meet the requirements, and the power user has equipment with strict voltage requirements, and it is not technically and economically reasonable to set up a voltage-changing device alone, a 10(6)kV on-load voltage-changing transformer can also be used. Article 4.0.9 The voltage deviation should meet the requirements of the voltage at the end of the power equipment, and the on-load voltage regulation of the power grid above 35kV should be implemented in the reverse voltage regulation mode. The range of reverse voltage regulation should be 0 to +5% of the rated voltage.
Article 4.0.10
When the power supply of impact loads needs to reduce the voltage fluctuation and voltage flicker of the power grid caused by impact loads (excluding the voltage drop allowed when the motor starts), the following measures should be taken:
1. Use dedicated power supply lines.
2. When sharing the distribution line with other loads, reduce the impedance of the distribution line. 3. The high-power impact load or impact load group and the load sensitive to voltage fluctuation and flicker shall be powered by different transformers. 4. The furnace transformer of the high-power arc furnace shall be powered by the power grid with larger short-circuit capacity.
Article 4.0.11 To control the distortion rate of the sinusoidal waveform of the power grid voltage caused by the harmonics generated by various nonlinear electrical equipment, the following measures shall be taken: 1. The transformers of various high-power nonlinear electrical equipment shall be powered by the power grid with larger short-circuit capacity.
Engineering Construction Standard Full Text Information SystemArticle 11
Electricity users with small loads should be connected to the regional low-voltage power grid. Engineering Construction Standards Full Text Information System
Engineering Construction Standards Full Text Information System
Chapter 4 Voltage Selection and Power Quality
Article 4.0.1 The power supply voltage of the power user should be determined based on the power capacity, the characteristics of the power equipment, the power supply distance, the number of circuits of the power supply line, the current status of the local public power grid and its development plan, etc., after technical and economic comparison. Article 4.0.2 When the power supply voltage is 35kV and above, the first-level distribution voltage of the power user should be 10kV. When the total capacity of the 6kV power equipment is large and the selection of 6kV is economically reasonable, 6kV should be used. The low-voltage distribution voltage should be 220/380V. Article 4.0.3 When the power supply voltage is 35kV, it can reduce the number of distribution and transformation levels, simplify the wiring, and is technically and economically reasonable, the distribution voltage should be 35kV. Article 4.0.4 Under normal operation, the allowable value of voltage deviation at the terminals of electrical equipment (expressed as a percentage of rated voltage) should meet the following requirements: 1. Motors: ±5%.
2. Lighting: ±5% in general workplaces; for small-area general workplaces far away from substations, when it is difficult to meet the above requirements, it can be +5%, -10%. Emergency lighting, road lighting and guard lighting are +5%, -10%. 3. Other electrical equipment is ±5% when there are no special regulations. Article 4.0.5 The design of the power supply and distribution system should meet the following requirements to reduce voltage deviation:
1. Correctly select the transformer ratio and voltage tap. 2. Reduce system impedance.
3. Take measures to compensate for reactive power.
4. Make the three-phase load balanced.
Article 4.0.6 When calculating voltage deviation, the voltage regulation effect after taking the following measures shall be taken into account:
1. Automatically or manually adjust the access capacity of parallel compensation capacitors and parallel reactors Engineering 6 Construction Standard Full Text Information System
Engineering Construction Standard Full Text Information System
2. Automatically or manually adjust the excitation current of the synchronous motor. 3. Change the operation mode of the power supply and distribution system. Article 4.0.7 When the transformer in the substation is in one of the following situations, the on-load voltage regulating transformer shall be used:
1. The step-down transformer in the substation with a voltage of 35kV or above directly supplies power to the 35kV and 10 (6)kV power grids.
2. The main transformer of the 35kV step-down substation, when the voltage deviation cannot meet the requirements.
10(6)kV distribution transformers should not use on-load voltage-changing transformers Article 4.0.8
; however, when the local 10(6)kV power supply voltage deviation cannot meet the requirements, and the power user has equipment with strict voltage requirements, and it is not technically and economically reasonable to set up a voltage-changing device alone, a 10(6)kV on-load voltage-changing transformer can also be used. Article 4.0.9 The voltage deviation should meet the requirements of the voltage at the end of the power equipment, and the on-load voltage regulation of the power grid above 35kV should be implemented in the reverse voltage regulation mode. The range of reverse voltage regulation should be 0 to +5% of the rated voltage.
Article 4.0.10
When the power supply of impact loads needs to reduce the voltage fluctuation and voltage flicker of the power grid caused by impact loads (excluding the voltage drop allowed when the motor starts), the following measures should be taken:
1. Use dedicated power supply lines.
2. When sharing the distribution line with other loads, reduce the impedance of the distribution line. 3. The high-power impact load or impact load group and the load sensitive to voltage fluctuation and flicker shall be powered by different transformers. 4. The furnace transformer of the high-power arc furnace shall be powered by the power grid with larger short-circuit capacity.
Article 4.0.11 To control the distortion rate of the sinusoidal waveform of the power grid voltage caused by the harmonics generated by various nonlinear electrical equipment, the following measures shall be taken: 1. The transformers of various high-power nonlinear electrical equipment shall be powered by the power grid with larger short-circuit capacity.
Engineering Construction Standard Full Text Information System
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.