Test stand for self-adaptive power recovering of hydraulic pump

Abstract

A test stand for self-adaptive power recovering of a hydraulic pump mainly comprises a tested pump loop, a loading motor loop, a compensating pump loop and a detecting element. The tested pump loop comprises a tested pump and a left reversing valve. The loading motor loop comprises a loading motor, a throttle valve and a one-way valve, and the throttle valve and the one-way valve are connected in series to the pipe between the left reversing valve and the loading motor. The compensating pump loop comprises a compensating pump, a safety valve and a right reversing valve, wherein the compensating pump is coaxially connected with an electromotor mechanically; an oil outlet of the compensating pump is communicated to an oil inlet of the safety valve and an oil inlet of the right reversing valve respectively; an oil return port of the safety valve is communicated with an oil tank; the right reversing valve is a two-position three-way reversing valve, and two working oil ports are respectively communicated with oil inlets of the oil tank and the loading motor. The detecting element comprises a pressure gauge, a high-pressure flow gauge and a torque speed sensor. The test stand for self-adaptive power recovering of the hydraulic pump, with applicability to tests of various hydraulic pumps, has the advantages of simple structure, great power recovering effect and high operational reliability.

Description

technical field [0001] The invention relates to a test bench, in particular to an adaptive power recovery test bench suitable for performance detection and reliability assessment of various hydraulic pumps. Background technique [0002] The hydraulic pump test bench is a necessary means for performance testing, reliability assessment and related law research of hydraulic pumps. The early hydraulic pump test benches were fully loaded by the overflow and throttling method, and the energy output by the motor was almost completely converted into heat energy. On the one hand, this made the test consume a lot of energy. The device consumes additional power. Especially when performing high pressure and large flow tests on hydraulic pumps, the energy consumption is even greater, and it may even have an impact on the relevant power grid. For this reason, the following energy-saving test methods using power recovery methods have been proposed: (1) Electric power recovery method, whi...

AI Technical Summary

Problems solved by technology

The early hydraulic pump test benches were fully loaded by the overflow and throttling method, and the energy output by the motor was almost completely converted into heat energy. On the one hand, this made the test consume a lot of energy. device, which consumes additional power

Especially for high-pressure and high-flow tests on hydraulic pumps, the energy consumption is even greater, and it may even have an impact on the relevant power grid.

For this reason, the following energy-saving test methods using power recovery methods have been proposed: (1) Electric power recovery method, which directly connects the outlet of the pump under test with the inlet of the loading motor, and the loading motor drives the generator to generate electric energy, which is passed through the inverter. Transform the feedback grid to achieve power recovery; since the feedback grid requires a set of devices to ensure that the regenerative power and the grid have the same phase, the implementation is technically complex, expensive, and the effect is not ideal. In order to prevent the load generator from reversing, it is necessary to increase safety control system, resulting in complex and large test equipment

(2) Mechanical compensation power recovery method, the tested pump is coaxially connected with the motor and the loading motor, the pressure oil output by the tested pump drives the loading motor to rotate, and the loading motor drives the tested pump through mechanical transmission. The motor, the tested pump, the loading motor, and the tested pump reciprocate to achieve the purpose of power recovery; but it has the following shortcomings: First, because the loading motor and the electric motor drive the tested pump at the same time, there will be "parasitic" power loss; The second is the existence of unavoidable overflow loss, and the size of the overflow loss depends to a large extent on the flow matching between the tested pump and the loading motor. If the matching is not proper, the power recovery effect is not ideal; the third is through the following methods Loading is carried out, that is, the output flow of the pump under test is more than the flow required by the loading motor, and the excess oil will cause "oil trapping" in the cavity formed by the connecting pipe between the two, and will flow from the active gap between the pump under test and the loading motor. Leaks out, so the test pressure for this loading method is susceptible to a variety of non-linear factors

(3) Hydraulic compensation power recovery method, the tested pump is mechanically connected with the loading motor coaxially, the outlet of the tested pump is connected with the loading motor inlet through a throttle valve for loading, and the compensation pump is connected in series or parallel in the hydraulic oil circuit In this method, a certain pressure oil is provided to compensate the insufficient energy of the system with hydraulic energy; when this method is used for hydraulic pump tests, some parameters cannot be changed, and only part of the test can be done, so it is mostly used for high-speed hydraulic motors, low-speed high-torque motors It is not suitable for hydraulic pumps; moreover, because it is necessary to adjust the size of the orifice to adjust the load and pressure, there is a throttling loss, which affects the power recovery effect

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