Modeling and Analysis of a Semiactive Power-Assisted Unit Based on Hydraulic Accumulator

Abstract

The hydraulic accumulator is widely used for storing energy in hydraulic system, but it is a passive device; the flowrate and volume of hydraulic oil adjusted by the accumulator are not well adapted to working-condition changes or payload disturbances. A novel semiactive power-assisted unit (PAU), which is a flow valve-controlled accumulator virtually, is proposed. The flowrate and volume of the accumulator can be regulated by adjusting the spool-opening of the flow valve. The mathematical model of the semiactive PAU is deduced. Then the static characteristic and dynamic characteristic of the PAU are presented. The simulations of the proposed PAU applied in variable-speed electrohydraulic drive system are implemented. The results show the influences of PAU's main parameters on its performance.

Development of the universal model of mechatronic system with a hydraulic drive

“…The developed mathematical model of a semiautomatic block with an amplifier based on a hydraulic accumulator [13] has enabled study of its static and dynamic characteristics. Mathematical models of the work processes occurring in pumps [14] and hydraulic motors [15] of the drive of movable operating elements of self-propelled machinery were offered but their interrelations and mutual influence have not been considered.…”

A comprehensive overview of hybrid construction machinery

“…61 However, its primarily function is as a power-assisted device for HCM. 62 The hydraulic storage approach converts the recoverable energy into hydraulic form, stores it in an accumulator, and releases it using secondary components or auxiliary cylinders. [63][64][65][66] Compared with an electric hybrid system composed of a battery or supercapacitor, a hydraulic accumulator as an energy storage device for HCM has the following advantages: (1) The hydraulic accumulator systems have an advantage in terms of the power density over an electric system; the hydraulic accumulator energy recovery systems are ideal for cases of frequent and short start-stop cycles in sufficient spaces.…”

Dynamic characteristics of coupling model of valve-controlled cylinder parallel accumulator

“…However, the active compensation control method often has problems such as large power consumption and sudden hit. The accumulator is an important hydraulic element, and it is widely applied when designing energy-saving and anti-damping systems [1][2][3]. Thus, the accumulator is applied in the valve-controlled luffing cylinder to reduce the power consumption.…”