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Product Overview: The MSpower series of low-voltage ride-through devices, as one of the safe power supplies for motors, are widely used in industries such as petrochemicals, steel, and intelligent manufacturing. Continuous production enterprises are affected by grid fluctuations, which can lead to voltage disturbances and sags. Voltage disturbances often originate from the higher-level power distribution system, and motors and frequency converters risk shutting down at any time. The concept of low-voltage ride-through originates from wind farms, and its purpose is to ensure that power generation can continue normally despite voltage drops caused by system failures, thereby reducing grid fluctuations. It has now been extended to various sensitive and critical loads that are started using frequency converters. In the event of disturbances in the power grid, there is a risk that the frequency converters will shut down, which could disrupt the continuity of the manufacturing process. The MSpower boost series of low-voltage ride-through cabinets, by integrating closely with frequency converters, ensures the continuous and safe operation of motors during transient disturbances in the power grid or short-term power outages. The MSpower Boost series of low-voltage ride-through devices, as a new generation of anti-vibration solutions for frequency converters, offer numerous comprehensive advantages over conventional motor safety power supplies. By conducting comprehensive measurements of the frequency converter’s input and output and intelligently identifying operating conditions, system bus technology is used to monitor in real time elements such as the rectifier module, boost module, DC bus voltage, and frequency converter bus voltage. The low-voltage ride-through unit features an industrial touch screen that provides real-time dynamic displays of operating conditions. It can be configured with an capacity equal to that of the motor, thereby reducing waste due to excess capacity ； Supports isolated multi-output, reducing system costs ； The device has a simple and effective structure, without adding any points of failure ； As well as comprehensive advantages such as low device power consumption and zero-latency activation of the bypass. Product features ☆ The low-voltage ride-through device features a fully enclosed cabinet, with strict separation between high-voltage and low-voltage circuits, ensuring strong interference resistance. ☆ Seamless integration with frequency converters, with good compatibility. ☆ The device operates in bypass mode, without increasing the risks of the original system. ☆ Dynamic tracking of busbar status, with zero investment and delay. ☆ One set of equipment can drive multiple frequency converters, with no circulating current between them. ☆ It features comprehensive device testing functions, facilitating on-site debugging and inspection. ☆ The system features redundant design for reliability and stability. ☆ System holographic recording, full life cycle prediction. ☆ Multiple self-check methods for key components ensure long-term stability and reliability of the device. ☆ An intelligent air-cooling system along with active heating and dehumidification systems ensure optimal operating conditions for the equipment. The MSpower boost series of low-voltage ride-through devices, with their various equipment and functional configurations, serve as important safety power supplies for frequency-conversion controlled motors. As energy-efficient and safe devices for maintaining operation during power fluctuations, they are used in frequency-conversion circuits of various sizes. Depending on the layout of the on-site control system and the required ride-through time, these devices come in the following models: The standard version of the MSpower boost series uses one device per frequency converter; there is no external DC power supply required. It is suitable for frequency converters with a capacity of 10 KW or less operating in a relatively stable power supply environment. This standard version can also be customized to support two frequency converters, with each converter having a capacity of no more than 5 KW. The MSpower boost backup series of low-voltage ride-through devices is suitable for environments with poor power supply and occasional outages, or situations where long periods of power loss occur due to switching operations on the high-voltage side of the power supply system. By adding an additional backup DC system to the standard version, it is possible to maintain operation during longer power outages; a typical configuration for backup use is one that can provide support for five minutes. If the system needs to remain operational during longer periods of power outage, then the MSpower battery series should be chosen to ensure the system can keep running for around 30 minutes. System overview: The MSpower boost series of low-voltage ride-through devices achieve this function by bypassing the inverter. They take three-phase AC power as input and produce DC power as output. When there is a voltage drop in the system, these devices quickly supply a stable DC power source to ensure the normal operation of the inverter. The schematic diagram of the device’s structure is shown below: https://nwzimg.wezhan.cn/contents/sitefiles2038/10192619/images/17008812.png Figure 1: Schematic diagram of the device’s structure. Three-phase AC power enters the three-phase rectification circuit through circuit breaker QF1. The pulsating DC voltage is used to pre-charge capacitor C1 via a current-limiting resistor; after pre-charging is complete, the direct current contactor KM1 is used to bypass the current-limiting resistor and fully charge capacitor C1. Inductor L1, together with Q1 and Q2, forms a BOOST-type step-up circuit that pumps the DC charge on C1 to a higher voltage to charge C2, and also charges capacitor C3 through a pre-charge current-limiting resistor. The charge then flows through a thyristor and diode circuit to prevent backflow, to the DC contactor, and from there, via a circuit breaker and fuse, to the DC bus of the inverter. At the normal operating voltage, the inverter relies on the DC power supplied by its internal bridge rectifier to function properly, while the BOOST boost circuit remains in standby mode ； When the grid voltage experiences an instantaneous drop and falls to a set value (default is 80%, which can be adjusted), the BOOST circuit activates promptly to deliver a stable DC voltage, thereby maintaining the stability of the DC bus voltage of the inverter and thus preserving the speed and torque of the induction motor. Once the grid voltage is restored (default is 90%, adjustable), the BOOST boost circuit shuts down automatically, and the inverter continues to supply power through internal rectification. This low-voltage ride-through device operates in bypass mode; no changes are required to the AC power supply circuit of the existing frequency converter, nor are any new settings necessary for the frequency converter. It only needs to be installed alongside the original frequency control cabinet. If the original control cabinet does not have a stable DC supply or an uninterruptible power supply, then the control circuit will disconnect when the system voltage drops. An uninterruptible power supply must be added during the system modification to maintain the operation of the original control circuit.