GB/Z 17625.13-2020Electromagnetic compatibility. Limits. Assessment of emission limits for the connection of unbalanced installations to MV, HV and EHV power systems (English PDF)

GB/Z 17625.13-2020 (Electromagnetic compatibility. Limits. Assessment of emission limits for the connection of unbalanced installations to MV, HV and EHV power systems) is available as an English-translated PDF.

GB/Z 17625.13-2020 — This part of the "Electromagnetic Compatibility Limits" is for unbalanced facilities (that is, three-phase facilities that cause voltage imbalance) to connect to public medium voltage, high voltage, and ultra The basic requirements of high-voltage power systems (low-voltage facilities will be regulated in other national standard documents) provide a guiding principle. Imbalance in this section Facility refers to a three-phase facility (which can be a load or power generation equipment) that causes an unbalanced system voltage. No access specifically for single-phase facilities Explain, because the access of such facilities is controlled by the system operator or owner. But when considering the access of single-phase facilities, these general The principles can also be applied. The main goal of this part is to guide the engineering practice of system operators or owners, so as to provide all connected users with Sufficient quality of service. But when it comes to facilities, this section is not intended to replace the emission limit standards for equipment. This part focuses on the capacity allocation of the system to absorb disturbance; it does not involve how to alleviate the disturbance and how to expand the capacity of the system. Since the criteria highlighted in this section are based on certain necessary simplifications and assumptions, there is no guarantee that this method will be effective for all injustices. Balance the load to provide the best solution. In terms of engineering, it is advisable to flexibly use and evaluate the recommended recommendations in all or part of the evaluation procedures. method. When facilities are connected to the system and may cause system imbalance, the system operator or owner is responsible for putting forward regulatory requirements. Usually show Disturbance facilities are understood as the user's complete facilities (that is, including balanced and unbalanced parts). The imbalances involved are basically divided into two categories. * Unbalanced facilities that absorb negative sequence current and generate negative sequence voltage in the power supply system. Such typical facilities include electric arc furnaces, electric Locomotives (usually connected to the public high-voltage power grid), and various unbalanced three-phase facilities (usually connected to the medium-voltage or low-voltage power grid). The negative sequence voltage is superimposed on the terminal voltage of the rotating machine, which will generate additional heat loss. Negative sequence voltage will also cause the converter equipment to produce Generate non-characteristic harmonics (usually the third harmonic in the positive sequence). * Connected to unbalanced facilities with neutral line system can also absorb zero sequence current. According to the wiring type of the power transformer, zero sequence The current may or may not be transferred to the power supply system. The zero sequence current flowing in the neutral grounded system will A zero sequence unbalanced voltage is generated in the phase voltage. Usually it is not by setting the emission limit to control the zero sequence unbalanced voltage, It is controlled through system design and maintenance. The neutral point is not grounded, or the facilities connected between the phases are not affected by this The influence of similar zero sequence unbalanced voltage. This section only provides guidance on how to coordinate the negative sequence voltage between different voltage levels to meet the compatibility level of the power point. Not right The zero sequence voltage imbalance limits the compatibility level. Compared with the negative sequence voltage imbalance, it is generally considered that the zero sequence voltage imbalance is between different voltage levels. Inter-coordination is irrelevant. But for the case where the neutral point is effectively grounded via impedance (that is, the ratio of the zero sequence reactance X0 to the positive sequence reactance X1 satisfies 0< X0/X1<=3), pay attention to this kind of voltage imbalance, especially when the connection method of the transformer allows the zero sequence component to penetrate between the medium voltage and the low voltage. Transparent occasions. Note. Since different countries have different delimitations of voltage levels (see 601-01-28 in IEC 60050-601.1985), this section uses system voltage The following terms. ---Low voltage (LV), refers to Un<=1kV; ---Medium voltage (MV), refers to 1kV \u003cUn<=35kV; ---High voltage (HV), refers to 35kV \u003cUn<=230kV; --- Extra high voltage (EHV), refers to Un >230kV. In this section, the function of the system is more important than the nominal voltage. For example, it can be specified that the "planning level" of the high-voltage system used for power distribution is between medium voltage and Between the planning levels of high-pressure systems.

......
This preview omits tables, figures, formulas and parts of the technical clauses. The complete document — all pages — is available in the English PDF.

1. 1Add to cart. Click the "Buy GB/Z 17625.13-2020" button on this page. You can add more standards before checkout.
2. 2Checkout. Enter your email and billing details. Payment is processed securely by Stripe (cards, Apple Pay, Google Pay supported).
3. 3Instant delivery (0–9 sec). Delivery is automatic: within seconds of payment you'll receive an email with a secure download link. The link stays valid for 72 hours.
4. 4Invoice included. A tax invoice is attached to the confirmation email. Need a custom invoice? Contact us.