Electrical control circuit for main motor of circulating cableway dragged by diesel generator

Abstract

The invention discloses an electrical control circuit for a main motor of a circulating cableway dragged by a diesel generator, which belongs to the field of diesel generator technology and passenger transport cableway motor dragging; the control circuit comprises a three-phase intelligent monitoring open-phase, overvoltage and undervoltage relay KC1 (short for three-phase power supply relay) and a frequency converter INV output voltage UV. The L1 end, the L2 end and the L3 end of the overvoltage and undervoltage relay KC1 are respectively connected with a fuse FU5, a fuse FU6 and a fuse FU7. According to the invention, a Siemens four-quadrant S150 frequency converter INV and a sudden stop circuit have a free parking function, and in a free parking mode, the S150 frequency converter does not generate feedback energy due to active electric braking, so that the cableway diesel generator and a main electric controller are effectively protected. When the novel control technology is adopted, the electric control operation state needs to be monitored, and when electric braking is generated under normal working conditions (including parking, peripheral equipment safety protection and host faults) and braking power is generated, real-time online monitoring is carried out.

Description

technical field [0001] The invention relates to the technical field of diesel generators, and more specifically relates to an electrical control circuit for a main motor of a diesel generator dragging and recirculating cableway. Background technique [0002] The new cableway standard requires that the cableway should be the drag control main part of the four-quadrant frequency converter or the four-quadrant DC governor, and the four-quadrant drive product is an energy-saving product in the electrical industry. It can not only use electricity, but also reversely send power to the grid. When the cableway fails or the electrical parking process occurs, the electrical braking generates huge energy that needs to be fed back to the grid. The frequency converter Or the DC speed controller realizes the task of energy-saving dragging and feedback energy transfer. The diesel generator replaces the mains power supply dragging, and uses a diesel generator whose rated power is 3-5 times ...

AI Technical Summary

Problems solved by technology

[0002] The new cableway standard requires that the cableway should be the drag control main part of the four-quadrant frequency converter or the four-quadrant DC governor, and the four-quadrant drive product is an energy-saving product in the electrical industry. It can not only use electricity, but also reversely send power to the grid. When the cableway fails or the electrical parking process occurs, the electrical braking generates huge energy that needs to be fed back to the grid. The frequency converter Or the DC speed controller realizes the task of energy-saving dragging and feedback energy transfer. The diesel generator replaces the mains power supply dragging, and uses a diesel generator whose rated power is 3-5 times the power of the main motor to drag, and the motor speed is the same as The size of the load must be strictly controlled to limit the size of its feedback power. The current working condition is to feed back energy to the grid and become a diesel generator body to bear. This approach is a very dangerous approach. First, the diesel generator receives the feedback energy. The impact is large, and the energy is uncontrollable with the change of load. There is a greater safety risk for diesel generators, electronic control components, and frequency converters (DC governors). Due to the high power of the cableway equipment, harsh conditions will lead to cableway electronic control and Diesel generators and frequency converters are burned, and the amount of loss can be huge and can reach millions

[0003] If two-quadrant frequency converters are used for the cableway constructed under the old standard, the frequency converter will not feed back energy to the power grid. When the cableway fails or the electrical shutdown occurs, the inverter’s back-to-inversion energy will accumulate on its DC bus, causing the voltage of the DC bus to rise. The braking unit (braking chopper) of the frequency converter is externally connected to a metal resistor, adopts the method of energy consumption braking, and consumes energy through the resistance. The braking unit performs braking, and the braking energy is consumed by the heat generated by the resistor. If it is driven by a diesel generator, when the frequency converter is in the air and restarts its working condition, it is already in the braking process, and suddenly stops electrically. When the frequency converter is electrically braked, and triggers a huge braking energy to the DC bus, it is normally consumed by the metal resistor on the brake unit of the frequency converter, and when the resistance reaches the limit, it will be burned, which will further cause the energy of the frequency converter to fail. Burn down the frequency converter due to consumption, and this kind of scheme is a non-energy-saving frequency conversion drive method. The new regulations do not allow the use of two-quadrant frequency converters, and it is rare for diesel generators to drive two-quadrant frequency converters in practical applications.

[0004] At the same time, the existing cableway main motor electrical control circuit cannot provide good protection for the power direction

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